US3652080A

US3652080A - Apparatus for cutting and folding flexible sheet material

Info

Publication number: US3652080A
Application number: US886269A
Authority: US
Inventors: Kenneth Thomas Jenkins
Original assignee: Kenneth Thomas Jenkins
Current assignee: NATIONAL RESEARCH DEVELOPMENT Corp KINGSGATE HOUSE 66-74 VICTORIA ST LONDON SW1 ENGLAND A BRITISH CORP
Priority date: 1968-12-24
Filing date: 1969-12-18
Publication date: 1972-03-28
Anticipated expiration: 1989-03-28

Abstract

Apparatus and a method for continuously measuring and transversely cutting into separate units flexible sheet material and particularly textile material as manufactured, folding the material adjacent a cut edge into a hem and temporarily securing folded hems in readiness for permanent securing.

Description

ljnited States Patent Jenkins [451 Mar. 28, 1972 APPARATUS FOR CUTTING AND FOLDING FLEXIBLE SHEET MATERIAL- Kenneth Thomas Jenkins, l4, Blackfield a e Salford, En nd Filed: Dec. 18, 1969 Appl. No.: 886,269

Inventor:

Foreign Application Priority Data Dec. 24, 1968 Great Britain ..6l,509/68 Dec. 24, 1968 Great Britain ..61,510/68 us. Cl. ..270/61 Eire/21" Int. Cl ..B65h 45/22 Field of Search ..270/78, 21, 93; 112/129, 147,

[56] References Cited UNITED STATES PATENTS 517,653 4/1894 Meisel ..270/78 1,962,361 6/1934 Piepenbring .270/93 1,978,282 10/1934 Piepenbring ..270/93 1,657,687 l/1928 Schuler "270/93 Primary Examiner-Robert W. Michell Assistant Examiner-Richard P. Dyer Attorney-Holman & Stern [5 7] ABSTRACT Apparatus and a method for continuously measuring and transversely cutting into separate units flexible sheet material and particularly textile material as manufactured, folding the material adjacent a cut edge into a hem and temporarily securing folded hems in readiness for permanent securing.

27 Claims, 13 Drawing Figures PATENTEDmzs 1912 7 3,652,080

sum u 0F 5 PATENTED MR 2 8 m2 SHEET 5 UF 5 Ofwl APPARATUS FOR CUTTING AND FOLDING FLEXIBLE SHEET MATERIAL This invention relates to apparatus for and a method of cutting and folding flexible sheet material, especially material for the making of articles such as curtains and other household soft furnishings which are cut from a continuous length of material, and folding hems on said material in preparation for a subsequent sewing operation whereby such hems are secured.

In cutting and folding operations whereby such articles are prepared it is desirable that the flexible sheet material to be cut and folded is flat and in a relaxed condition as manufactured and that said operations are performed without the imposition on the material fibers of any strains which could distort the relaxed condition of the material and might therefore lead to a distortion of the formed articles, and, in order to form straight hems of uniform width, it is also desirable that the folding operations are performed in such manner that the hems are folded along lines parallel to the cut edges of the material.

The object of the present invention is to provide automatic apparatus for and a method of cutting and folding flexible sheet material for the continuous production of material units having transverse edges folded into hems, such apparatus in creasing the speed of manufacture of such material units and reducing the labour force hitherto required to perform the necessary operations satisfactorily.

According to the invention there is provided apparatus for cutting and folding flexible sheet material, comprising a work surface adapted to support said material fed thereto as a continuous length in a relaxed condition as manufactured, cutter means for cutting the supported material transverse its length, first gripping means for gripping the longitudinal edges of the material at opposed locations to one side of the cutting line, second gripping means for gripping the longitudinal edges of the material at opposed locations to the other side of the cutting line, said first and second gripping means being rotatable so as to fold into a hem the portion of material bordering each cut edge, and means for temporarily securing the hems in position prior to permanent securing of same.

Also according to the invention there is provided a method of cutting and folding flexible sheet material whereby a continuous length of material resting in a relaxed condition on a work surface has transversely opposite portions of its longitudinal edges and a transverse strip of material between said opposite portions gripped and held, at spaced positions adjacent to and on each side of a predetermined position where the material is to be cut transverse its length, and after cutting, a portion of material bordering each cut edge is folded to form, respectively the trailing hem of a leading unit and a leading hem for a next following unit.

An embodiment of the invention will now be described by way of example with reference to the accompanying drawings in which:

FIG. I is a pictorial view of the apparatus,

FIG. 2 is a transverse elevational view of a gantry means of the apparatus,

FIG. 3 is a plan view of a pair of rotatable jaws for gripping part of a longitudinal edge of the material, and,

FIG. 3a is a cross-sectional view of jaws shown in FIG. 3,

FIG. 4 is a cross-sectional view of the folding mechanism at one side of a set of rotatable gripping and folding means,

FIG. 5 is a plan view of an upper fold controlling element, and,

FIG. 5a is an enlarged fragmentary sectional perspective view at line X-X of FIG. 5,

FIG. 6 is a plan view of a lower fold controlling element, and,

FIG. 6a is an enlarged fragmentary sectional perspective view at line Y-Y OF FIG. 6,

FIG. 7 is a pictorial view of an auxiliary gripper,

FIG. 8 is a pictorial view of a displaceable support unit,

FIG. 9 is a pictorial view of a carrier unit for securing folded hems, and,

FIG. 10 is a diagram of the circuit connections for the apparatus for measuring the positions where the material is to be cut and folded.

A horizontal work surface 1 (FIGJ) arranged at a suitable height above floor level is adapted to receive and support a continuous length of flexible sheet material such as textile fabric of any required width which is fed from a source thereof so as to pass longitudinally in a relaxed condition from the upstream end 2 towards the downstream end 3 of said work surface, there being intermediate said upstream and downstream ends and at one side of the work surface, hereinafter referred to as the measuring side, a measuring point indication 4 which may for example be the zero point on a scale 5, calibrated in units of length, and extending downstream of said point.

Associated with said measuring point and extending across the work surface transversely to the path of movement of the material thereon, there is a gap 6 to provide a working space for apparatus, described hereinafter, for cutting the material and folding the cut ends to form hems.

Also associated with the measuring point and arranged to straddle the work surface, there is provided gantry means 20 (FIG.2) whereof side frames 21 support the extremities of a set of guide rails 22 which are parallel to and extend across the work surface from side to side, which guide rails support for movement therealong a cutter unit assembly 23 comprising a disc-shaped rotary knife 24 and its driving motor 25 the arrangement of the cutter unit and guide rails being such that the blade of the rotary knife lies in a plane normal to the work surface so as to efiect a transverse cut through material resting thereon at a predetermined cutting line position related to said measuring point indication. Provision may be made for the gantry means to support two adjustably spaced parallel sets of guide rails on a common horizontal plane each with an associated cutter unit. The or each cutter unit is moved along its guide (FIG. 4) by an endless chain 26 driven by a reversible electric motor 27.

The side frames of the gantry means are extended laterally to provide, at opposite sides of said work surface, supports 28 for movable platform units 29 which carry means for gripping and controlling the material during cutting and subsequent hem-folding processes, said platform units being capable of controlled movement, towards or away from the longitudinal edges of the material, along a path that is parallel to the cutter unit guide rails, and the material gripping and controlling parts carried by oppositely situated platform units being arranged to operate in unison and having interacting opposed parts of the gripping and folding means on common axes also parallel to the cutter unit guide rails. Mechanical and functional details of movable platform units 29 will be described hereinafter.

Rotatable gripping means for folding and controlling the material are arranged in two sets of co-axial parts, one set being adjacent to and upstream of the cutting line along which an associated cutter unit will cut the material, and the other set being adjacent to and downstream of an associated cutting line, each said set of parts being arranged to grip adjacent portions of opposite longitudinal edges of the material so as to control the transverse strip of material therebetween during a cutting operation and subsequent single or double turnover folding operation according to requirements, the arrangements of the driving mechanisms for said sets of parts being such that they perform their sequential operations substantially simultaneously and without the imposition of any forces which would cause the material on the work surface to be disturbed from its relaxed condition.

In both upstream and downstream sets of opposed rotatable gripping means, the assemblies which grip the longitudinal edges of the material each comprise upper and lower horizontal jaws 39 and 40 (FIG.3a) respectively which are symmetrically disposed at levels respectively above and below the plane of the material on the work surface and are arranged for vertical movement towards or away from each other between open and closed positions, said upper jaw 39 (FIG.3a) having a vertical longitudinal slot 41 wherein there is a vertically pivotable rocker element 42 whereof one arm has a plurality of downwardly extending pins 43 and the other arm has an extension 44 to engage an upper surface part of said lower jaw 40 said rocker element with pins and extension constituting a retractable claw for automatically transfixing the gripped material when the jaws reach a closed position towards which they are biased by spring means 45 by which said jaws are fixed to the mechanism part 70 (F164) whereby they are rotated, and there being, associated with said spring means 45, a pneumatically operable thruster means 46 engaging rollers 47 whereby the jaws are forced apart when they are not required to grip the material. The lower jaw 40 is provided with a transverse slot 48 to receive the pins of the claw when the jaws are closed, and a spring 49 is provided on the upper jaw 39 to retract said claw when the jaws are opened.

In each set of rotatable gripping means the jaw assemblies extend towards each other from eccentric seatings 70 (F104) on opposed axial faces 71 of control gearwheels 72 which constitute rotatable parts of the folding mechanisms, said control gearwheels being rigidly fixed on co-axial stub-shafts 73 spaced at a short distance away from the jaw edge that is remote from the cutting line, and mounted for rotation about their common axis in the free ends of crank arms 74 which themselves are rotatable about the common axis of co-axial support spindles 75 which are rotatably carried in journal bearings 76 extending from sub-platform members 30 (FIG.2) mounted on the movable platform units 29 in a manner to be described hereinafter. Rigidly fixed on spindles 75 so as to be in tooth-intermeshing engagement with the control gearwheels are gearwheels 77, the control gearwheels 72 and gearwheels 77 being of the same pitch circle diameter. Fixedly mounted adjacent to those ends of spindles 75 that are remote from gearwheels 77 are driving gearwheels 78 which are in tooth-intermeshing engagement with driving pinions 79 rotatable by single fold driving means 80, which may be reversible geared electric motors or linkage operated by pneumatic thrusters, adapted to rotate said driving gearwheels through I80. Mounted on crank arms 74 so as to rotate therewith are crank arm gearwheels 81 engaging crank arm driving pinion 82 of double fold driving means 83 of a kind similar to single fold driving means 80 but adapted to drive the crank arms through 180. The driving means of opposed folding mechanisms are preadjusted to run at the same speeds, and the intermeshing alignment of all gearing is such that when neither the single fold driving means nor the double fold driving means are actuated the associated jaws have their gripping surfaces substantially parallel to a horizontal common radial plane extending from the common axis ofthe stub-shafts 73. A selector switch (not shown) is provided whereby the energising power for the driving means can be directed to either the single fold driving means or the double fold driving means.

Where the hem of a material unit is to be single fold hem, as for example the top hem of a curtain which is to be provided with a draw tape, the double fold driving means 83 of the downstream set of rotatable gripping means will not be activated and will prevent crank arms 74 from rotating about the axis of support spindles 75, but the activating of single fold driving means 80 will cause the spindles 75 to rotate in unison through an angle of 180 driving the control gearwheels so that the opposed pairs of jaws gyrate about the common axis of the stub-shafts without changing their alignment relationship to one another as they move along an arcuate path below the plane of the work surface from a position upstream of the common axis of the stub-shaft to a position downstream thereof.

When, however, the upstream hem of a leading material unit is to be a double fold hem, as (FIG. 5) a transverse hem of a bed-sheet, the single fold driving means 80 of the downstream set of rotatable gripping means will not be activated and will prevent spindles 75 and gearwheels 77 from rotating, but the activating of double fold driving means 83 will cause the crank arms 74 to rotate through an angle of 180 about the common axis of spindles 75 and thus carry the coaxial stub-shafts along an arcuate path below the plane of the work surface from a position upstream of co-axial spindles 75 which a position downstream thereof, the gyratory motion of the control gearwheels about gearwheels 77 causing the coaxial stub-shafts to rotate in unison in the same direction and by a similar right-angles about their common axis, the rotation of the stub-shafts causing the opposed jaws to gyrate about the common axis of the stub-shafts as the common axis of the stub-shafts gyrates about the common axis of spindles 75, without changing the alignment relationship of the opposed jaws to one another.

Associated with the opposed pairs of jaws of the sets of rotatable gripping means so as to extend therebetween during cutting and single or double folding operations are upper and lower fold controlling elements 50 (FIGS) and 61 (FlG.6) respectively which, in conjunction with one another and the associated jaws, hold and support the transverse strip of material extending between the opposed jaws. These upper and lower fold controlling elements are removable parts of the apparatus which, after completion of the folding operation and the opening and withdrawal of the opposed jaws, remain in attachment to the folded material unit until a subsequent final securing operation has been completed. Each such element is in the form of a slat of variable length, and each has at its remote extremities locating grooves 59 (FIGS. 5 and 6) which engage pegs 60 at the extremities of the open opposed jaws as the jaws move transversely relative to the material towards the position where they will close and grip the longitudinal edges of the material.

The upper fold controlling elements 50 (FIGS) each comprise three aligned elongate members whereof the center member 51 is a relatively static member, and the outer members 52 are relatively movable members, said members all having support shells 53 of recumbent Ushaped form. The space within the horizontal webs of the support shells of the movable members is filled by fixed elongate stiffeners 54 whereof one edge 55 extends beyond the extremities of said webs and is rounded to provide a smooth seating for material becoming engaged therewith. The elongate stiffeners of the movable members project beyond those ends of the support shells adjacent the static members to provide guide extensions which pass into and are freely slidable in the space between the horizontal webs of the static member shell, there being guide pins 56 of the static member which pass through elongate slots 57 in said extensions to limit the range of inward and outward sliding movement of the movable members and there also being spring members 58 within the static member to urge the movable members towards their outward limits of movement.

The lower fold controlling elements 61 (FlG.6) are each similar to the upper fold controlling elements 50 (FIGS) but differ therefrom in that the elongate stiffeners within the shells of the movable members are each in two pieces, the pieces 62 which extend into the static member being rigidly fixed in position, and the other pieces 63 being freely slidable in the spaces between the horizontal webs of the support shells of the movable members, said pieces 63 being linked to their related shells by pivotable parallel links 64 of equal length in such manner that said pieces 63 remain parallel to their respective shells in all positions to which they can be moved from a closed position, wherein they completely fill the spaces between the webs of their respective shells, to an open position where the links are at right-angles to the pieces 63 thus expanding the effective width of the moving members of said lower fold controlling element. Biasing springs 65 are provided within the shells of said movable members to urge said pieces 63 away from related pieces 62 and towards the closed position at which position extensions 66 of those ends of pieces 63 that are remote from pieces 62 project outwardly beyond the free ends of the movable members.

Both upper and lower fold controlling elements have, near their remote ends, substantially vertical through-going holes 67 (H085 and 6) the purpose of which will become apparent hereinafter.

In use, the upper and lower fold controlling elements are positioned respectively above and below the material on the work surface so that the closed sides of the support shells of both are vertically in line and are parallel to and facing towards the position where the material will be cut, the arrangement providing that as the associated jaws move towards the position where they will close to grip the longitudinal edges of the material, they will first engage the projecting extensions 66 of the pieces 63 of the lower fold controlling element causing said pieces 63 to move to their expanded open position where their rounded edges will project beyond the rounded edges 55 of the stiffeners of the upper fold controlling element. Thereafter continued engaging movement of the jaws will progressively reduce the effective lengths of both upper and lower fold controlling elements until the jaws reach the gripping position. The object of the expansion of width applying to the lower fold controlling element will become apparent hereinafter.

The upper and lower fold controlling elements, when conjoined with associated jaws are movable together therewith, and they are fed into position for engagement with the jaws from magazines mounted transversely relative to the work surface at upstream and downstream positions above and below the level of the material resting thereon, the upper and lower magazines being arranged to feed a related kind of fold controlling element into its operative position after measuring movement of the material has ceased and before the related jaws are caused to move to the gripping position.

The opposed movable platform units 29 (FIG.2) that are mounted on the gantry means to carry the sets of material gripping and controlling parts and which, as aforesaid, are capable of controlled movement towards and away from the longitudinal edges of the material, are provided with sub-platform members 30 (FIG.2) that support, separately, the two sets of rotatable gripping means already described and the means whereby the movable parts thereof are rotatable, which sub-platform members 30 are slidable, in a direction at rightangles to the direction of motion of the movable platform units 29 whereon they are mounted, by controlled driving means 31 which may include rack and pinion elements actuated by reversible geared electric motors or linkages operated by pneumatic thrusters, the driving means for the sub-platform members of opposed rotatable gripping means being coupled so that they operate in unison. The object of the available movement of the sub-platform members will become apparent hereinafter.

In addition to carrying sub-platform members 30 and the associated apparatus, the opposed movable platform units 29 provide pivots and pivot supports whereon are mounted spaced opposed pairs of non-rotatable auxiliary grippers 12 (F lG.7), each of which auxiliary grippers comprises upper and

lower jaws

13 and 14 respectively which are substantially parallel to and extend by the same amount as the jaws of said rotatable gripping means, the jaws of each auxiliary gripper being movable in a substantially vertical direction towards or away from one another between open and closed positions, and each jaw forming a terminal part of a related arm of a pair of

arms

15 and 16 pivotally carried by a common pivot 17 of the associated part of the related movable platform unit 29 in such manner as to provide that said arms are movable with a scissors-like action. Spring means 18 are provided to cause the jaws of each auxiliary gripper to move to and remain in the closed position, and a pneumatic thruster unit 19 is provided for each auxiliary gripper to cause the jaws thereof to open against the force exerted by the biasing spring means 18, the pneumatic thruster of all auxiliary grippers and the sets of rotatable gripping means being connected in parallel to provide that all operate simultaneously. The spacing of the opposed pairs of auxiliary grippers is such as to provide that one of the opposed pairs is mounted downstream of the downstream set of rotatable gripping means at a position clear of the paths of movements of said rotatable gripping means and the actuating mechanisms thereof, and another of the opposed pairs of auxiliary grippers is mounted upstream of the upstream set of rotatable gripping means at a position clear of the paths of movement of said rotatable gripping means and the actuating mechanisms thereof. In use the auxiliary grippers hold the material adjacent to the folding apparatus to prevent movement thereof during cutting and folding operations.

Each of the opposed movable platform units 29 (FIG.2) is provided with a biasing device, such as a spring or a weight attached t9 a cable passing over a pulley, which applies a relatively small substantially constant predetermined force to move said platform unit outwardly from the material on the work surface. The opposed movable platform units 29 are each controlled by an impeller mounted on gantry support extension 28 (F102) and actuated by driving means 32 (FlG.2) which may be a reversible geared electric motor or linkages operated by pneumatic thrusters, said impeller being arranged to oppose said biasing force and move the associated platfonn unit towards the material in the work surface, such movement continuing until both opposed platform units have reached predetermined positions where their jaws are in position to grip the longitudinal edges of the material, whereat automatic actuation of control switch means (not shown) de-emergizes the pneumatic thrusters of the rotatable gripping means and the auxiliary grippers allowing all open jaws to close, and also causes reversal of the direction of motion of the impellers controlling the movements of the opposed movable platform units. The closing of the gripping jaws and the transfixing of the gripped material by the claws of the jaws of the rotatable gripping means, and the subsequent moving away of the platform unit impellers allows the opposed platform units to move outwardly under the combined influence of the biasing devices and the springs of the fold controlling elements, but only until they reach a position where the transverse tension in the material between opposed jaws counterbalances said combined biasing forces, this position being that at which subsequent cutting and folding operations are performed. The opposed platform units are thus brought to a halt but their respective impellers continue to move outwardly relative to the work surface until they reach the outer extremities of their movement paths where their driving means are automatically de-energized, the impellers thereafter constituting stop members against which the platform units will come to rest when their jaws have been opened after a folding operation has been completed.

To prevent the fold controlling elements and the material held thereby from sagging during cutting and folding operations, there are in the gap of the work surface and below the positions where the sets of rotatable gripping means effect folds, displaceable support units 99 (FlG.8) extending transversely relative to the material to be cut and folded, and arranged to support said fold controlling elements during all phases of the cutting and folding operations, said displaceable support units each comprising, a pivotable support framework 100 (FIG.8) having spaced side members 101 which are parallel to the path of the material on the work surface and have their ends remote from the folding position mounted on coaxial pivots of the side frames of the gantry means, a spaced pair of cross-shafts 102 extending between said side members at positions adjacent to the free ends thereof each said crossshaft having mounted thereon a freely rotatable co-axial tubular roller 103 extending over the width of the material on the work surface and one of the cross-shafts being adjustable relative to the other to provide that the spacing therebetween can be varied, a plurality of relatively narrow endless fabric belts 104 that are axially spaced in guide grooves along said rollers so as to form tight loops about both rollers, and biasing means (not shown) to counterbalance the weight of the free end of said support unit and apply a small upward thrust thereto. In operation the upper surfaces of the upper runs of the fabric belts of both displaceable support units 99 form support surfaces that will receive and support the weight of the associated fold controlling elements when they are fed to their respective operative positions from their respective upper and lower magazines, which support surfaces will, during a folding operation, move freely in the direction of motion taken by those parts of the associated fold controlling elements and material wrapped thereabout that at any time during said operation are resting on and being supported by said surfaces, thus preventing sagging of said elements and ensuring that at no time is there any relative slip between contacting parts to cause the material being folded to move relative to the associated fold controlling elements by which it is held. Except during a folding operation displaceable support units are locked in their receiving positions by electromagnetically releasable automatic catches (not shown) of the gantry side frame.

Arranged to co-operate with the fold controlling elements of each of the upstream and downstream sets of gripping and controlling parts, are carrier units 110 (FIG.9) constituting removable parts of the apparatus which are provided to hold said elements and the hems folded thereabout during transporting and final securing operations subsequent to folding. These carrier units are brought into operation after a fold has been made and before the grippingjaws have released the longitudinal edges of the material, each such unit being an elongate composite girder arranged to extend transversely across the full width of the work surface and comprising two horizontally disposed parallel tubes 111 supported intermediate their ends by adjustable stop blocks 112 and adjacent their ends by rigidly fixed support blocks 113, there being between each support block and its adjacent stop block an axially slidable member 114 which is urged towards the support block by helical thrust springs 115 mounted on said tubes. Each axially slidable member 114 is furnished with a foot extension 116 having a horizontal underside surface 117 from which extends a downwardly projecting plurality of parallel pins 118 of a length substantially equal to the combined thicknesses of the upper and lower fold controlling elements and the hem material entrapped therebetween and wrapped thereabout. Each foot extension is also provided with an arm 119 carrying a cam follower 120 whereby the axially slidable member can be moved in opposition to the thrust springs, and each support block is provided with a pair of extensions 121 that releasable engage a pickup link of an adjacent chain of a vertically disposed parallel pair of endless link-chains 122 (FIG.1) whereby carrier units are lowered onto folded hems for engagement therewith, and is also provided with an extension 123 (F169) that engages a pick-up link of an adjacent chain of a horizontally disposed spaced parallel pair of endless linkchains 124 (FIG.1) whereby an engaged carrier unit is moved to a predetermined position for a subsequent operation.

For controlling the placing of the carrier units on the folded hems there is, mounted from the side frames of the gantry means so as to extend along the path down which a carrier unit is lowered to its operative position, an opposed pair of downwardly convergent control cam surfaces 125 (FlG.2) whereof the angle of convergence can be adjusted to suit variations in width of material, which cam surfaces are engaged by the cam followers of a descending carrier unit to cause the axially movable members of the unit to move inwardly to a position where the downwardly projecting pins 118 thereof will enter and pass into the aligned throughgoing holes 67 (FIGS. and 6) of the upper and lower fold controlling elements to provide that when the carrier unit comes to rest on the folded hem and automatically releases itself from the vertical conveying chains its pins 118 will be in engagement with said fold controlling elements and the material controlled thereby and will hold said material in the attitude and under the lateral tension conditions applying when it was folded, and will also prevent the aligned parts of the fold controlling elements from being moved axially by their springs when the jaws of opposed rotatable gripping means release the longitudinal edges of the material and are withdrawn from engagement with the ends of said elements. Subsequent moving of an engaged carrier unit to a position where its cam followers are clear of the camsurfaces does not cause any substantial change of attitude or conditions affecting the folded material because the springs of the fold controlling elements cause said elements to lock on the throughgoing pins of the carrier unit and, in combination with the carrier unit thrust springs, maintain the material substantially in the lateral tension condition applying when it was folded.

To provide that the hems of material units such as curtains made from patterned material may be related to a selected pattern feature thereof, the gantry means comprises two separate relatively spaceable support structures straddling the work surface at positions relatively upstream and downstream of each other. The downstream said structure 7 (F101), hereinafter referred to as the downstream gantry structure," mounts apparatus for cutting the material and folding the trailing hem of a leading material unit, which apparatus includes, (a) a set of guide rails with cutter unit assembly; (b) a pair of opposed movable platform units as 29 (F162) complete with impellers and impeller driving means, the opposed downstream auxiliary grippers, the downstream set of rotatable gripping means with the related driving means, and subplatform members and means for controlling movement of same; (c) the appropriate magazines for fold controlling elements; (d) a related displaceable support unit; and (e) the means for depositing a carrier unit on a folded hem. The other said structure 8 (F161), hereinafter referred to as the upstream gantry structure," mounts apparatus for cutting the material and folding the leading hem of the next following material unit, which apparatus includes, (al) a set of guide rails with cutter unit assembly; (bl) a pair of opposed movable platform units as 29 (FlG.2) complete with impellers and impeller driving means, the opposed upstream auxiliary grippers, an opposed pair of intermediate auxiliary grippers which are adjacent to said cutter unit and downstream thereof, the upstream set of rotatable gripping means with the related driving means, and sub-platform members and means for controlling movement of same; (cl) the appropriate magazines for fold controlling elements; (d1) 21 related displaceable support unit; and (e1) the means for depositing a carrier unit on a folded hem.

Each gantry structure is carried by a wheeled carriage 33 (F161) mounted on guide rails 34 arranged longitudinally below the work surface, each wheeled carriage being provided with a reversible geared electric motor 35 arranged to drive a shaft 36 whereon pinions 37 are fixed so as to engage racks 38 of the longitudinal guide rails 34, thus providing that said wheeled carriages are capable of independent controlled movement relative to one another along the rails.

Each of the upstream and downstream gantry structures is so mounted from its wheeled carriage as to be horizontally pivotable about the axis of a vertical pivot pin (F 10.2) extending downwardly from the structure so as to be in pivotal engagement with a pivot pin socket 131 mounted on the part of the wheeled carriage adjacent to the measuring point indication at the measuring side of the work surface, the parts of the structure remote from the pivot pin being supported on rollers 132 running on track surfaces 133 of the wheeled carriage, and there being at a position remote from said pivot axis an operating extension 134 of the structure engaging a floating nut 135 that is in screw-thread engagement with a horizontal lead-screw 136 mounted on the wheeled carriage so as to be parallel to the path of movement of the material on the work surface which lead-screw is rotatable about its axis in either direction by a geared electric gantry pivoting motor 137 mounted on said wheeled carriage, the pivoting and supporting arrangement for said structure being such as to permit it to be orientated through angles of up to 10 on each side of a line at right-angles to the path of movement of the material on the work surface.

Adjustably slidable on guide members 9 (FlG.1) supported, at a level above the level of the work surface, from the side frames of the upstream gantry structure 8 so as to be parallel to its cutter unit assembly guide rails, are two electronic pattern point sensing devices arranged so that each is near a related one of the longitudinal edges of the material on the work surface and can be positioned so as to be activatable by the passing of a predetermined point in each longitudinal repeat of the design on those parts of the material nearest its longitudinal edges. Signals from either or both said sensing devices will activate appropriate controller elements whereby the gantry pivoting motors of both upstream and downstream gantry structures are energised to cause the associated leadscrews to rotate in a direction that will pivotally move the two gantry structures from previously held parallel positions to required parallel positions where their cutter guide rails and the common axes of their associated material gripping and controlling parts are parallel to a line between design repeat points at each side of the material on the work surface.

Referring back to FIG. 4, it will be seen that the mechanism is arranged so that the normal width of a double fold hem is determined by the distance between the axes of the stub-shafts 73 and the support spindles 75. Where, however, it is required to produce a hem of different width than said normal width, the driving means 31 (FIG.2) of the sub-platform members 30 mounted on the movable platform units 29 of the appropriate gantry structure are energized by the apparatus controller during or immediately following a folding operation to cause said sub-platform members to move away from their normal positions and carry the related rotatable gripping means and the gripped and folded part of the hem under the undisturbed material to a position predetermined as being that which will yield a hem of the required different width than the normal width. The relative longitudinal movement of the sub-platform members is also imparted to the means for depositing the carrier unit on the folded hem so that the carrier will be properly positioned relative to the line along which the hem will eventually be sewn.

It is a general requirement, in the making of curtains from material having a repeat pattern, that the pattern feature at the bottom hems of all curtains of the same length shall be the same, but it will be appreciated that if curtains of the same length are made successively, there is a probability that there could be considerable wastage of material between the positions where the cuts for the top hem of a leading curtain and for the bottom hem of the next following curtain are to be made. To mitigate this wastage it is preferred to arrange that successively produced curtains shall be of different lengths predetermined as being those which, in relation to the spacing of pattern repeats of the material, will yield an economic range of sizes wherein the pattern feature at the bottom hem of each curtain of each one of the sizes in the range is in a specific relationship to a selected point in the repeating pattern so that, for example, for a given pattern repeat spacing, the cut for the bottom hem of, say 4 feet, 6 inches long curtains would always occur 1% inches in front of a selected pattern repeat point, whereas the cut for the bottom hem of, say 6 feet, 0 inch curtains would always occur 3% inches in front of the selected pattern repeat point. It is therefore arranged that the controller for the present apparatus is programmed to provide that for each successively produced curtain the apparatus is automatically adjusted so that said cuts are effected with the minimum of waste to yield identical curtain of sizes within a predetermined range. This is performed in the manner illustrated in circuit diagram F1610 which shows diagrammatically the following apparatus and the circuit arrangements related thereto:

i. The motor MM for the conveyor for advancing the material after folding. The motor is equipped with an electromagnetically operated brake and is controlled by a contactor marked CM in FlG.ll0.

ii. The motor MU (35 in FIG.2) for moving the upstream gantry structure longitudinally relative to the work surface. This motor is reversible and is equipped with an electromagnetically operated brake, the winding for making the motor drive said gantry structure downstream being controlled by a contactor marked CD in F1610,

and the winding for making the motor drive said gantry structure upstream being controlled by a contactor marked CU in FIG. 10.

iii. A counting switch C of a kind used in automatic telephony as a multi-way selector switch wherein electromagnetically operated ratchet mechanism causes a wiper arm of a rotor to engage in succession each contact of a bank of contacts which are insulated from each other, and in particular is of a type having four banks each of fifty contacts and two parallel pairs of wiper arms, the wiper arms of each pair being electrically connected and arranged at to each other so that for each revolution of the rotor each pair of wiper arms successively engages each of one hundred contacts. In FIGJO the banks of contacts of C are numbered 1-4 respectively, the wiper arms of banks 1 and 2 constituting one pair, the wiper arms of banksv 3 and 4 constituting a second pair. The electromagnetic step-by-step motor for driving the rotor C is shown as MC an is furnished with a circuit interrupter i which opens when the coil of motor MC is fully energized. The pairs of wiper arms are shown in their normal unoperated condition with the wiper arms of banks 1 and 3 engaged with Zero contacts. The spacing between each contact of a bank represents one convenient unit of distance along the work surface, as for example one-fourth inch or three-sixteenths inch or oneeighth inch. Each of contacts 1-99 of banks 1 and 2 is connected to a releated contact of a selector switch in the controller which selector switch is arranged to extend switch energizing power to a selected contact which represents a required cutting distance upstream of a selected pattern repeat point. For clarity, in FIGJO only the connections to contacts 149-50-71 and 99 are shown, contact 71 being included, by way of example, as a selected contact indicating that the cut to be made by the cutter of the upstream gantry structure is to be 71 units of distance beyond a selected pattern repeat point and so, by inference, a required number of units of distance before a next following pattern repeat point. All contacts of banks 3 and 4 except the Zero contact are shown as being connected together.

iv. Measurement switches as Mll to M5 in FlG.l0 are spaced apart at predetermined distances from the measuring point 4 (FIG.1) along the measuring side of the work surface downstream of said measuring point, and are arranged to be operated by the arrival of the carrier holding the downstream hem of a leading curtain unit. A selector switch of the controller is arranged to extend switch energizing power to that switch M which is predetermined as being that which will yield a leading curtain of a required length.

v. Preparation switches as P1 to P5 in FlG.10 are each electrically connected to, but are not mechanically operable with, an associated measurement switch of the same number, said preparation switches being positionally adjustable so as to be fixable at a point upstream of its paired measurement switch at a distance somewhat greater that the distance between pattern repeat points on the material being processed.

vi. An impulser, indicated at G1 in F1610 is arranged to close and open a switch each time the conveyor moves the material downstream through one unit of distance.

vii. A similar impulser, indicated at G2 in FIG.10 is arranged to close and open a switch each time the upstream gantry moves through one unit of distance.

viii. Relay switch units of a kind used in automatic telephony, indicated in FlG.]l0 as follows:

SStart Relaywith two sets of normally open contacts.

SA-Start Auxiliary Relay-with one set of normally open contacts and one set of normally closed contacts.

A-Preparation Relaywith two sets of normally open contacts.

E-Count Relay-with two sets of normally open contacts.

i ll

B-Measurement Complete Relay-with two sets of normally open contacts and three sets of normally closed contacts.

USGUpstream Gantry Relay-with one set of normally open contacts.

LMOvement Direction Relay-with two sets of normally open contacts and one set of normally closed contacts.

PR-Position Reached Relay-with one set of normally open contacts and one set of normally closed contacts.

PH PREPARE Home Relay with one set of normally open contacts and one set of normally closed contacts. HHoming Relay-with two sets of normally open contacts and one set of make-before-break contacts.

ix. Change-over switch 2, operated by the upstream gantry structure when its cutter enters into coincidence with the measuring point on the work surface.

In use, completion of a previous process operation causes the closing of a two-pole start switch, one pole of which extends switch energizing power to the coil of relay S which energizes and holds on via closed normally open contacts s1 and normally closed contacts b4. Closing of normally open contacts s2 extends switch operating power via normally closed contacts b2 to contactor CM which energizes so that an electricity mains circuit is closed at cm to cause the motor MM, for driving the material conveyor and the horizontal chain conveyors which engage the carriers securing folded Items, to start and continue running so that the material and the carriers attached thereto are moved downstream. The simultaneous closing of the other pole of the start switch extends switch operating power to relay Sa which energizes and holds on via closed normally open contacts sal and the normally closed side of make-before-break contacts h3. Opening of normally closed contacts m2 breaks a controller circuit whereby a subsequent process operation could be initiated.

Movement of the material along the work surface by its conveyor eventually causes the selected preparation switch, indicated by way of example in FlG.l as P4, to be operated by the carrier on the bottom hem of the leading curtain so that switch energizing power is extended to relay A which energizes and holds on via closed normally open contacts a1 and normally closed contacts [14. Closing of normally open contacts a2 prepares a circuit from the electronic pattern point sensing devices EDI (10 in F101) above the measuring side of the work surface, to relay E so that when said device sends a signal to both relay E and the gantry structure orientating means as the selected pattern repeat point passes thereacross due to the continuing movement of the material, relay E will be energized and will hold on via closed normally open contacts el and normally closed contacts b4. The energizing of relay E causes normally open contacts e2 to close and extend switch energizing power via normally closed contacts b to conveyor drive impulser G1 so that from that instant every unit of distance moved by the material causes step-by-step motor MC to be energized to move the wiper arms of counting switch C forward from one contact to the next.

Continued ad ancement of the material eventually causes the selected measurement switch, for example M4, to be operated so that relay B is energized and holds on via closed normally open contacts bl and normally closed contacts ph2. Normally closed contacts b2 are thus opened to break the circuit to contactor CM thereby causing the opening of operated contacts cm and the consequent de-energising of the conveyor motor MM which is stopped instantly by the motor brake. At the same time normally open contacts b3 are closed to cause relay USG to be energised, normally closed contacts b4 are opened to break the hold circuits for relays A,E and S so that those relays de-energize and restore their contacts to normal, and contacts 175 are opened to break the circuit to impulser G1.

At this instant of time the leading curtain has been accurately measured and its cutting line is in perfect coincidence with the measuring point and the cutter of the downstream gantry structure, and a wiper arm of banks 1 or 2 of C is standing on an unselected contact, for example contact 59, representing the exact distance between said cutter and the selected pattern repeat point which by now is downstream of said cutter. Moreover, as one of the contacts of banks 1 or 2 of C, for example contact 71, has been selected as being that representing the position where the cutter of the upstream gantry must be to cut the material for the next following curtain, the number of contact steps which said wiper arm would have to take to reach the selected contact represents exactly the number of units of distance between the cutter of the downstream gantry structure and the required position of the cutter of the upstream gantry structure.

When the closing of contacts b3 caused the energising of relay USG, its normally open contacts usgl closed to extend switch operating power via unoperated contacts of switch Z and normally closed contacts l2 to contactor CD which energises to close its normally open contacts cdl and thus energise the winding of Motor MU that causes the upstream gantry structure to be driven downstream. The upstream gantry structure therefore moves downstream until its cutter enters into coincidence with the measuring point and the cutter of the downstream gantry structure at which position it operates change-over switch 2 causing its contacts to change over thus breaking the circuit to contactor CD which de-energises causing motor MU to stop and its brake to be applied. The changing-over of the contacts of switch Z completes a circuit from closed contacts usgl to relay L which energises and holds on via closed normally open contacts l1. Normally closed contacts 12 open to ensure that the energising circuit for contactor CD will not be re-established when switch Z restores to normal as the upstream gantry structures moves away from the measuring point, and normally open contacts l3 close to extend switch operating power via normally closed contacts prl to contactor CU which energises, and also to impulser G2 of the upstream gantry structure. Energising of contactor CU causes the closing of normally open contacts cal and the consequent energising of the winding of motor MU that causes the upstream gantry structure to be moved upstream. Each unit of distance of such movement of the upstream gantry structure causes impulser G2 to send an energizing impulse to step-bystep motor MC whereby the wiper arms, which have been in engagement with an unselected contact, for example contact 59, are stopped in the same direction as previously from one contact to the next so that when the cutter of the upstream gantry structure reaches the required position the wiper arm of the bank of C concerned will engage the selected contact, for example contact 71, completing a circuit from the selector switch of the controller via the selected contact and engaged wiper arm to relay PR which will energise causing normally closed contacts prl to open and break the circuit to contactor CU so that the motor MU is stopped and its brake applied. At this time the material is exactly in the position where it will be cut to yield a leading curtain of the required length, and the upstream gantry structure is in the position where its cutter will cut the material at a required distance from a pattern repeat point.

The energizing of relay PR also caused the closing of normally open contacts pr2 thereby extending switch energising power to relay PH which energizes so that normally open contacts phl close to extend switch energizing power to relay H, and at the same time normally closed contacts ph2 are opened to break the hold on relay B which de-energises and restores its operated contacts to normal. Relay H energizes, closing normally open contacts h2 which then extend switch energizing power via any contact of banks 3 and 4 except the Zero contact, and the wiper arms of banks 3 and 4 to the interupters i of step-by-step motor MC so that said motor operates automatically to step the wiper arms from contact to contact until they reach the Zero contact where no switch energising power is available. At the same time that contacts h2 were closed, normally open contacts hl were also closed so that relay H remains energised through a hold circuit from the wiper arms of banks 3 and 4 until said wiper arms reach the Zero position.

Also at the same time, make-before-break contacts h3 were operated to transfer the hold on relay SA to the circuit from the wiper arms of banks 3 and 4 so that when that circuit is broken at the Zero position said hold will be broken for long enough to enable relay SA to de-energize and restore its normally closed contacts and thus enable the controller to initiate a subsequent process step. It will be appreciated that when the wiper arm of bank 1 or 2 is automatically stepped out of engagement with the energized selected contact, the relay PR de-energizes restoring its contacts to normal thus causing relay PH to de-energises and also restore its contacts to normal thereby ensuring that by the time normally closed contacts sa2 are restored to normal, all apparatus associated with the counting means is in its unoperated condition.

The automatic continuous production, from a continuous length of relaxed flexible sheet material, of accurately sized material units having transverse hems prepared for subsequent final securing, is effected during automatically controlled cycles of operation during which the trailing hems of leading material units and the leading hems for next following units are prepared simultaneously. One such cycle will now be described by way of illustration starting from the phase where prepared hems have been secured and are ready for being moved.

Completion of depositing a carrier unit 110 (FIGS) on each of the trailing hem of a leading material unit and the leading hem for a next following unit, actuates switch means whereby the pneumatically operable thruster units 46 (FIG.3) and 19 (FlG.7) of all pairs of gripping jaws are energised to cause the jaws to open allowing the associated platform units 29 (FlG.2) to retreat under the influence of their biasing means towards the position where they will engage the stop members of their impellers.

Withdrawal of the jaws of the rotatable gripping means from the ends of the upper and lower fold controlling elements will allow the pieces 63 (FIG.6) of said lower fold controlling elements to be restored to the closed positions by their biasing springs, all elements being otherwise locked against movement of their parts by pins 1 18 (F169) of the associated carrier units. Where the fold controlling elements have been controlling the material of a double fold hem, the closing of said pieces 63 will provide that the part of the fold that had been supported by said pieces becomes a free transverse sewing loop of material arranged at the inner extremity of the hem for subsequent permanent securing during a later sewing operatron.

When the retreating movable platform units engage the stop members of their impellers, each actuates switch means to cause operated movable parts associated with the rotatable gripping means and the sub-platform members to be restored to their normal pre-operated positions, and when all said movable parts are in the pre-operation position they actuate switches connected in series in a circuit for activating the controller means for closing the two-pole start switch (FIG.10) which activates the means for measuring a leading material unit and adjusting the position of the upstream gantry. The process of measuring and adjusting then proceeds in the manner already described, during which process a preceding material unit with both hems folded is moved downstream towards a take-off position and the uncut material with a folded leading hem is drawn by the attached carrier unit across the gap in the work surface to the position where it is ready to be cut and folded at predetermined locations to provide the trailing hem of a leading material unit and the leading hem of a next following material unit.

Where the advancing material has a repetitive pattern, the electronic pattern point sensing devices (F161) mounted on the upstream gantry structure automatically cause the upstream and downstream gantry structures to be orientated in the manner previously described so that their cutter guide rails and the common axes of the associated material gripping and controlling parts are brought into parallelism with a line between design repeat points at each side of the advancing material. It will be appreciated that when the material being fed to the apparatus is in one continuous piece, the amount of re-orientation of the gantry structures necessary between successive material unit lengths will generally be very small, and it will also be appreciated that when the material being fed to the apparatus has a plain unpatterned finish, the use of the automatic means for orientating the gantry structures and the use of the means for adjusting the position of the upstream gantry structure to vary the spacing of the two gantry structures can be dispensed with, and the gantry structures can be pre-set at such adjacent positions that only one cutter unit is brought into operation, both gantry structures being preorientated so that their cutter guide rails and the axes of the associated material gripping and controlling parts are substantially parallel to the average lie of the weft of the material.

To dispense with the use of said automatic orientation and gantry adjustment control means, the switch energising power supply to the electronic pattern point sensing devices is cut off, a connecting link cll in the energising circuit of relay USG (F1010) is removed, and a connecting link cl2 in the hold circuit of relay SA (FlG.10) is transferred to the hold circuit of relay S (FIGJO). The measuring process will thus be able to operate as already described but without the activation of the counting switch and upstream gantry adjustment means.

The completion of the measuring process and the restoration of contacts sa2 (FIGJO) to their normal closed condition causes the activation of the means whereby upper and lower fold controlling elements are fed from their respective magazines to positions above and below the material and in alignment with the associated opposed pairs of jaws of the rotatable gripping means at which positions the combined weights of associated upper and lower fold controlling elements are supported on the related displaceable support units 99 (FIGS) which units at that time are locked in the receiving positions by automatically engaging catch units of the gantry structures.

When the fold controlling elements have been placed in position, the devices whereby they are fed from their magazines actuate switches to cause the impeller driving means 32 (P102) to advance the movable platform units 29 (FIG.2) so that the upper and lower jaws of all opposed pairs of jaws are advanced towards and respectively over and under the longitudinal edges of the material on the work surface, the extremities of the jaws of the rotatable gripping means engaging associated extremities of related fold controlling elements causing the pieces 63 of the lower said elements to move to the open position, and thereafter progressively reducing the effective lengths of said elements as the jaws continue to advance.

As soon as the opposed pairs of jaws have moved across the longitudinal edges of the material by a predetermined amount, the movable platform units on which they are supported actuate jaw control switches which cause the de-energizing of the jaw-opening thrusters 46 (F103) and 19 (FIG.7) allowing the jaws to close automatically to grip said material edges, and in the case of the jaws of the rotatable gripping means to transfix the material with their claws, said jaw control switches also causing the direction of movement of the impellers to be reversed so that they move away from the movable platform units which units follow the impellers until arrested when the transverse tension in the strips of material gripped between opposed jaws of counterbalances the biasing force tending to move said platform elements towards the retreating impellers. This transverse tension, which can be varied to suit the kind of material being processed, is pre-adjusted to be sufficient to apply a straightening effect on the weft of the material without the imposition of any undue stresses which could cause permanent distortion of the relaxed material.

When the retreating impellers reach the outer extremities of their movement paths, they actuate switches which cause their driving means to be stopped, at the same time activating a cutter controller to cause the driving motors 25 (F 16.2) of the cutter units, and the cutter unit traversing motors 27 (FIG .2),

to be energized so that each cutter unit effects a transverse cut across the material on the work surface. It is to be appreciated that where the material being processed is unpattemed, or where the material has a pattern wherein the distance between design repeats is small so that unwanted excess material can be accommodated within the hems, the spacing between the upstream and downstream gantry structures will be small, and only one cutter unit need to be brought into operation, whereas where the distance between cutting positions is larger than can be so accommodated, the spacing between said gantry structures will be correspondingly larger so that it is necessary to use both cutter units and allow the cut material therebetween to drop out.

When the material has been cut from side to side, the direction of motion of the traversing motors 27 (FlG.2) is automatically reversed to cause the cutter units to be restored to their out-of-use position whereat they actuate switches to cause the displaceable support units 99 (FIGS) to be released for movement by the withdrawal of the automatic catches which hold them in a receiving position, said withdrawal causing the actuation of control switches whereby selected single fold driving means 80 (FlG.4) or double fold driving means 83 (FICA) are are energized to effect the required kinds of folds in the manner previously described. During the folding operation the displaceable support units move with and support the fold controlling elements extending between associated gripping jaws. When said selected driving means have caused the driven parts to rotate through 180 they automatically bring the folding mechanism to a halt, at which stage the displaceable support units will again be in their receiving posi tions where they become locked by said automatic catches. Where a hem of different width than the normal width is required, the controller, during or immediately after the folding of the hem, causes the activation of the driving means for the sub-platform members of the related opposed movable platform units so that said sub-platform members are moved in the manner described hereinbefore, said driving means bringing the sub-platform members to a halt when a hem of the required width is achieved.

When the driven parts of the folding mechanisms have been rotated through 180 by their selected driving means and when the sub-platform members are in predetermined positions they automatically actuate control switches connected in series in a circuit such that completion of all folding movements causes the activation of switch means whereby the motor or other means which drives the vertically disposed parallel pairs of endless chains 122 (FlG.l) are energized. These pairs of endless chains constitute movable magazines for carrier units 110 (FIG.9) and are arranged so that energizing of their driving means moves each pair of chains by that amount which will cause a carrier unit to be deposited, in the manner previously described, on the associated hem and its fold controlling elements which at that time are non-resiliently supported on the locked displaceable support unit. When the carrier units are firmly bedded down on the related folded hems they automatically release themselves from said chains. The depositing and releasing of said carrier units concludes the described cycle which then repeats.

It will be seen that during such cycle the material being processed has been measured, and then cut and folded as it lay stationary on the work surface, without at any time being subjected to a condition which could change its relaxed nature. Further, it will be appreciated that ifa material unit with only one transverse hem is required the apparatus controller is preset so that only the appropriate rotatable set of gripping means is caused to rotate.

What is claimed is:

1. Apparatus for cutting and folding flexible sheet material, comprising a work surface adapted to support said material fed thereto as a continuous length in a relaxed condition as manufactured, cutter means for cutting the supported material transverse its length, first gripping means for gripping the longitudinal edges of the material at opposed locations to one side of the cutting line, second gripping means for gripping the longitudinal edges of the material at opposed locations to the other side of the cutting line, said first and second gripping means being rotatable so as to fold into a hem the portion of material bordering each cut edge, and means for temporarily securing the hems in position prior to permanent securing of same.

2. Apparatus as claimed in claim 1, wherein the first and second gripping means are caused to rotate substantially simultaneously to fold respectively the trailing hem of a leading material unit and the leading hem for a next following material unit.

3. Apparatus as claimed in claim 1 wherein means is provided whereby the rotatable gripping means can be caused to rotate to produce either a single fold prepared hem or a double fold prepared hem as required.

4. Apparatus as claimed in claim 1, wherein the means for temporarily securing the hems in position prior to pennanent securing of same are removable carrier units which are deposited on the folded hems prior to their release from the first and second gripping means.

5. Apparatus as claimed in claim 4, wherein each carrier unit comprises an elongate element extending transversely across the work surface and provided towards each end with a member adapted to engage a related folded hem, said members being capable of guided movement apart and together lengthwise of the elongate element and being biased into the apart position.

6. Apparatus as claimed in claim 5, wherein said members are slidable on guides of said elongate element and are resiliently urged apart and are provided with a plurality of downwardly extending pins arranged to engage a folded hem and the fold controlling elements associated therewith.

7. Apparatus as claimed in claim 5, wherein said members are provided with cam followers to engage associated cam surfaces of the gantry means to move said members towards one another to a predetermined position for engagement with a folded hem and the fold controlling elements engaged therewith.

8. Apparatus as claimed in claim 5, wherein the elongate element is provided with extensions that releasably engage pick-up links of a parallel pair of vertical conveyor chains which deposit said elongate element on a folded hem, and is also provided with extensions that engage pick-up parts of a pair of horizontal conveyor means by which said element and an attached secured hem are moved along the work surface to a position for a subsequent operation.

9. Apparatus as claimed in claim 1, wherein the cutter means is substantially normal to and intersecting the plane of the work surface and arranged for movement along guide rails supported by gantry means straddling said work surface.

10. Apparatus as claimed in claim 9, wherein the gantry means comprises two separate relatively spaceable support gantry structures straddling the work surface at positions relatively upstream and downstream of each other, the downstream gantry structure providing support for means for cutting the material transverse its length and said first gripping means and associated mechanism for controlling supporting folding and securing the trailing hem of a leading material unit, and the upstream gantry structure providing support means for cutting the material transverse its length and said second gripping means and associated mechanism for controlling supporting folding and securing the leading hem for a next following material unit.

11. Apparatus as claimed in claim 10 wherein each of the support gantry structures is carried by a wheeled carriage mounted on guide rails arranged longitudinally below the work surface said carriage being drivable along said rails by a reversible electric motor controlled by controller means.

12. Apparatus as claimed in claim 11, wherein the support gantry structures are movably mounted on their wheeled carriages so as to be horizontally pivotable about vertical axes, there being driving means of each wheeled carriage whereby the associated support gantry structure can be pivotally moved from a previously held position to a position where its cutter guide rails and the common axis of rotation of its associated gripping jaws will be parallel to a line between design repeats at each side of a patterned material on the work surface.

13. Apparatus as claimed in claim 12, wherein the upstream gantry structure is provided with a spaced pair of electronic pattern point sensing devices mounted on a guide member that is parallel to the cutter guide rails and to the work surface, said pattern point sensing devices being adjustable along said guide member to positions where they will be activatable by the passing thereacross of a predetermined point in each longitudinal repeat of a pattern design on those parts of the material nearest its longitudinal edges, it being arranged that signals from either or both said pattern point sensing devices cause the activation of controller means whereby motors of the driving means for pivotally moving upstream and downstream gantry structures are automatically caused to run in a required direction to pivotally move both said structures from previously held parallel positions to required parallel positions where their cutter guide rails and the axes of rotation of associated rotatable gripping means will be parallel to a line between design repeats at each side of the material on the work surface.

14. Apparatus as claimed in claim 13 wherein one of the electronic pattern point sensing devices forms part of control means for automatically adjusting the spacing of the upstream and downstream gantry structures in accordance with predetermined requirements.

15. Apparatus as claimed in claim 14 wherein the control means for automatically adjusting the spacing of the upstream and downstream gantry structures automatically determines the positional relationship between a selected pattern repeat point of a patterned material and a corresponding point on an upstream transverse line along which the material will be cut by the cutter unit of the downstream gantry structure to yield a leading material unit of a required length, and automatically causes the upstream gantry structure to move to a position where its cutter unit will cut the material along a transverse line at a predetermined distance downstream of the next following pattern repeat point.

16. Apparatus as claimed in claim 15, comprising control means for operating the gripping means, cutting means, folding means, securing means, measuring means, and gantry structure spacing means, in automatic predetermined and inter-related sequence.

17. Apparatus as claimed in claim 9, wherein the gantry means provides supports for locationally opposed movable platform units from which said rotatable gripping means and the means for rotating same are carried, said platform units being simultaneously movable towards or away from one another between opposed positions where the gripping parts of said rotatable gripping means can grip the longitudinal edges of the material on the work surface and positions where said parts are clear of said work surface.

18. Apparatus as claimed in claim 17 wherein said rotatable gripping means and the means for rotating same are carried from said locationally opposed movable platform units by means including a sub-platform member of each said platform unit which sub-platform members are movable in unison in a direction at right-angles to the direction of movement of said platform units.

19. Apparatus as claimed in claim 18 wherein the sub-platform members carrying the rotatable gripping means from said opposed movable platform units can be caused to carry the related rotatable gripping means and the gripped and folded part of the hem along a path below the undisturbed material to a predetermined position that will yield a hem of different width than that determined by the rotation of the rotatable gripping means.

20. Apparatus as claimed in claim 17 wherein said locationall opposed movable platform units carry opposed nonrotata le auxiliary grippers which are operable in unison with the gripping parts of said rotatable gripping means and are arranged to hold the longitudinal edges of material adjacent to said cutter means and said rotatable gripping means to prevent movement of said adjacent material during cutting and folding operations.

21. Apparatus as claimed in claim 17 wherein said opposed movable platform units are biased to apply a straightening action to the transverse strips of material between said locationally opposed gripping parts after the longitudinal edges of said material have been gripped.

22. Apparatus as claimed in claim 17, wherein the opposed gripping parts of the rotatable gripping means each comprise two opposed pairs of upper and lower jaws furnished with retractable claws which pass through the material adjacent its longitudinal edges when the upper and lower jaws are moved towards one another to grip said longitudinal edges.

23. Apparatus as claimed in claim 22 wherein the upper and lower movable jaws of opposed rotatable gripping means are adapted to engage respectively adjacent ends of removable upper and lower slot-like fold controlling elements of self-extending variable length which when so engaged extend above and below the strip of material between said opposed pairs of jaws to hold and control said strip during cutting, folding and securing operation.

24. Apparatus as claimed in claim 23, wherein the lower fold controlling element comprises means whereby at least a part of its effective width is automatically increased when said element is engaged by the associated jaws and is automatically restored to normal when released from said jaws to provide that a fully prepared double-fold hem will be furnished with a free transverse sewing loop of material at the inner extremity of the fold of the hem.

25. Apparatus as claimed in claim 23, wherein the upper and lower fold controlling elements for the rotatable gripping means are fed into position for engagement with related opposed jaws from associated magazines mounted transversely relative to the work surface at positions respectively above and below the level of material resting on the work surface.

26. Apparatus as claimed in claim 23, wherein there are provided displaceable support units having freely movable surfaces arranged to move with and support said fold controlling elements of each of the rotatable gripping means together with the material held thereby during cutting, folding, and securing operations.

27. A method of cutting and folding flexible sheet material whereby a continuous length of material resting in a relaxed condition on a work surface has transversely opposite portions of its longitudinal edges and a transverse strip of material between said opposite portions gripped and held, at spaced positions adjacent to and on each side of a predetermined position where the material is to be cut transverse its length and after cutting, a portion of material bordering each cutedge is folded to form, respectively, the trailing hem of a leading material unit and a leading hem for a next following material unit.

Claims

4. Apparatus as claimed in claim 1, wherein the means for temporarily securing the hems in position prior to permanent securing of same are removable carrier units which are deposited on the folded hems prior to their release from the first and second gripping means.

20. Apparatus as claimed in claim 17 wherein said locationally opposed movable platform units carry opposed non-rotatable auxiliary grippers which are operable in unison with the gripping parts of said rotatable gripping means and are arranged to hold the longitudinal edges of material adjacent to said cutter means and said rotatable gripping means to prevent movement of said adjacent material during cutting and folding operations.

23. Apparatus as claimed in claim 22 wherein the upper and lower movable jaws of opposed rotatable gripping means are adapted to engage respectively adjacent ends of removable upper and lower slat-like fold controlling elements of self-extending variable length which when so engaged extend above and below the strip of material between said opposed pairs of jaws to hold and control said strip during cutting, folding and securing operation.