US3571846A

US3571846A - Expansion support platform for tenter machine guide rail sections

Info

Publication number: US3571846A
Application number: US793817*A
Authority: US
Inventors: William Tomlinson
Original assignee: Bevis Industries Inc
Current assignee: Bevis Industries Inc
Priority date: 1969-01-24
Filing date: 1969-01-24
Publication date: 1971-03-23
Anticipated expiration: 1988-03-23
Also published as: DE6927103U; DE1966729A1; GB1238594A; DE1934759B2; DE1934759A1; DE1934759C3

Abstract

This disclosure relates to a platform for supporting adjacent pivotally connected guide rail section ends which expand and contract due to heating and cooling and also more toward and away from each other under the influence of saddle adjustment. This invention relates to a platform for supporting the ends of pivotally connected tenter clip guide rail sections as adjustment of the saddle places the ends in angular relationship or as expansion and contraction of adjacent guide rail sections causes the opposite ends thereof to move toward or away from each other.

Description

United States Patent Inventor William Tomlinson East Providence, R.I. Appl. No. 793,817 Filed Jan. 24, 1969 Patented Mar. 23, 1971 Assignee Bevis Industries, Inc.

Providence, RI.

EXPANSION SUPPORT PLATFORM FOR TENTER 3,179,977 4/1965 Nash ..l

Primary Examiner-J. Spencer Overholser Assistant Examiner-David S. Safran Attorney-William Frederick Werner ABSTRACT: This disclosure relates to a platform for support- 2 3 m? St m 29" SECTIONS ing adjacent pivotally connected guide rail section ends which expand and contract due to heating and cooling and also more us. Cl 18/1 toward and away from each other under the influence of sad- B29g 7/00 dle adjustment. Thisinvention relates -to afplatform .for Fieldoi Search 18/1 (FB) supporting the ends of pivotally connected tenter clip guide rail sections as adjustrnent of the saddle places the ends in References Cited angular relationship or as expansion and contraction o f a d UNITED STATES PATENTS jacent guide rail sections causes the opposite ends thereof 7 3,179,976 4/1965 Nash 18/ 1 to ov w r or way from each other.

a M EA f iua fl 5c 9 aw v v II I 37 2 72 E 2/5 82 L /7 3 474 lm o 0 I76 0 o I 3 13/4 I656 496 66 o 0 38A 5 q I n n n M in than I I /4 9? /4A ,45 x-ic 2 l 22 224 2 2 c i -i;

PATENTEDMAR23I9Y:

SHEH 1 OF A INVENTOR WILLIAM TOMLlNSON ATTORNEY PATENTED MAR23 197:

SHEET 2 [IF 4 INVENTOR WlLLlAM TOMLINSON TORNEY PATENTED M19123 l97| 3,571, 45

SHEET 3 0F 4 INVENTOR WILLIAM TOMLINSON F i G. 6 ATTORNEY PATENT ED NA23|97| 3,571,846 sum UF 4 INVENTOR WILLIAM TOMLINSON BY JIM 54M flaw) ATTORNEY EXPANSHQN @UMPORT PLATFORM lFGR TENTER MACHIINE GlJlllDlE EARL SECTHONS in the past tenter machines had a commercial length of between 60 and 80 feet. in this distance the hinge pin, pivotally connecting adjacent ends of oppositely located guide rail sections, moved a linear distance of approximately 8 inches. The saddle,adjustably supporting the hinge pin and opposite ends of two guide rail sections, was wide enough to support the guide rail ends at the maximum angle adjustment between the ends of two guide rail sections. The saddle was also wide enough to accommodate the 8-inch linear movement of the hinge pin, movable due to the thermal expansion and contraction of adjacent guide rail sections.

With the advent of laterally stretching plastic film, to reduce the medial thickness of the film, tenter machines are built in excess of 120 feet long and the angular relation of adjacent ends of guide rail sections has increased in order to provide a stretching zone dictated by the physical characteristics of the plastic film. The stretching zone is the complementary contour of oppositely located guide rail sections formed inthe tenter machine. The movement of the hinge pin exceeds 21 inches. A saddle to accommodate increased movement of the hinge pin and increased angularity of adjacent guide rail section ends would have to be larger than is commercially practicable.

Applicant has solved the problem of supporting adjacent ends of guide rail sections in both longitudinal movement and angular lateral movement by providing telescoping slide plates. The lower plate is slidably supported upon the saddle. The upper slide plate is slidably supported upon the lower slide plate and supports the hinge pin and ends of adjacent guide rail sections at maximum angular relation while providing a smooth guide rail path for the travel of the tenter clip chain through the multiple guide rail sections.

A tenter guide rail path must be smooth. if a jar is imparted to a tenter clip, the plastic film, in heat-softened condition, is rendered economically useless.

Accordingly, it is an object of the present invention to provide a platform for supporting pivotally connected adjacent guide rail section ends upon a saddle, whereby, saddle adjustment of the hinge pin finds support for the hinge pin and adjacent guide rail section ends in the telescoping slide plates forming the platform.

Another object of the present invention is to provide a support for the hinge pin and adjacent pivotally connected ends of guide rail sections, wherein the maximum angularity between adjacent guide rail section ends are supported to provide a smooth tenter clip path at the juncture of adjacent guide rail sections.

Other objects of the present invention will become apparent inpart and be pointed out in part in the following specification and claims. I

Referring to the drawings in which similar characters of reference indicate corresponding parts:

FlG. l is a plan view of a tenter machine in accordance with the present invention.

H6. 2 is a right sidefelevational view,

a partly in section, taken along line 2 2 of l lG. ll.

l-"lG. 3 is a fragmentary perspective view, partly in section,

of the saddle, a guide rail section, and the telescoping slide plates constituting the platform, with the guide rail shown at maximum angle to the saddle.

FlG. d is a view similar to FlG. 3, showing the guide rail section perpendicular to the saddle, at maximum heat expanded position.

PEG. 5 is a perspective exploded view of the several parts constituting the new and improved platform.

MG. 6 is a vertical cross-sectional view talten along line 6-6 of FllG. t.

HG. 7 is a view, similar to FIG. 5, illustrating a modified form of structure constituting a platform for tenter machine guide rail section ends.

HO. 3 is a view, similar to FIG. 6, illustrating the modified structure shown in FlG. 7, in relation to the saddle of a tenter machine.

FlG. 9 is a vertical sectional view taken on line 9-9 of FIG. 1, with the rail structure left off.

in proceeding with this invention, reference is made to the drawings, wherein is illustrated a tenter machine, in accordance with the present invention.

The machine illustrated, see FIGS ll, 2 and 9, consists of a left side frame if and a rightside frame l2 which are in the form of l-beams.

A plurality of legs or standards 13 are fixed to left and right side frames ill and 12, respectively as by welding, to support said frames ll, 112 at a preselected distance above a floor.

A plurality of crossmembers B7, 17A, 17B, ll7C, etc., are fastened, by means of welding, to left side frame ill at 15, 15A, 153, etc., and to right side frame 12 at 14, MA, MB, etc.

Each

crossmember

17, 17A, 173, etc., is machine finished to provide a track consisting of a top 30 and opposite sides 31, 32, for purposes which will presently appear.

A plurality of bearings, 18, 18A, 188, MC, etc., are adapted to engage tops 30, 30A, 308, etc., respectively, and grip opposite sides 31, 32; 31A, 32A, 31B, 328; etc., respectively, over left side frame ll. Bolts 20 fasten bearings l3, l8A, 188, etc., to crossmembers l7, l7A, 1178, etc., respectively. A corresponding plurality of

bearings

19, 19A, 198, etc., are adapted to engage tops 30, 30A, 308, etc., respectively, and grip opposite sides 31, 32; 31A, 32A; 31B, 328, etc., respectively, over right side frame l2. Bolts 9 fasten

bearings

19, 19A, 198, etc., to crossmembers l7, ll7A, l7B, etc., respectively.

A plurality of center bearings 24, 24A, 24B, etc., engage crossmembers 117, WA, 178, etc., respectively, in a manner described for bearings 18 and i9. Bolts 33 fasten bearings 24, 24A, 248, etc., respectively, to crossmembers l7, 17A, 178 etc., respectively.

A plurality of shafts 21, 21A, ZllB, etc., are provided with bearing

surfaces

345, 35, 36, which are rotatively mounted in bearings l8, l9 and 24, respectively. Shafts Zll, 21A, 218 etc. are provided with a right hand thread 31%, 38A, 388, etc., respectively, for purposes which will presently appear.

A plurality of

hand wheels

22, 22A, 228, etc., are fastened to one end of

shafts

21, 21A, 218 etc., respectively, for the manual rotation thereof.

A plurality of saddles db, 40A, 408, etc., are provided with sliding faces ill, MA, MB, etc., and sliding ends 42, 43; 42A, 43A; 42B, 438, etc., respectively, to slidingly engage tops 30, 36 A, 308, etc., and slides 31, 32, etc., respectively.

The construction of saddle 40 will be described. lt will be understood that saddles WA, 40B, 40C, etc., are identical in construction.

Saddle 490 is provided with a plurality of inverted

U-shaped projections

50, 51,54 and 55 which form

chambers

56, 57 and 6th inverted U-shaped projections $0, 5t, 54, 55 straddle shaft 2i to allow shaft 21 to freely rotate. A nut bl provided with a screw thread of a hand adapted to rotatively engage left hand thread 38 is located in chamber 56 and is held therein by means of inverted

U-shaped projections

50, 51.

Rotation of hand wheel 22 causes nut bl to engage either inverted Ushaped projection 56 or St to slide saddle 40 upon crossmember l7 toward or away from bearing H9.

The conventional construction of a tenter machine has just been described. The new and improved construction will now be described.

A block lllil is fastened to the medial area of saddle M), as by welding. A lower plate 101 is provided with a recess, generally indicated by reference numeral 99, formed by means of sides N2, 503 and bottom Mid, and an opening M35 having sides 1%. Lower plate ltll, through lower sliding surface 167, is slidably mounted upon bearing surface lltlti of saddle til, with opening 105, through sides we, slidably engaging the sides lltlilA and ltlllB of block ltlil. Opening W5 is therefore longer in a longitudinal direction, so as to allow lower plate lilll to slide longitudinally relative to saddle at).

A batten plate 110 is located in recess 99 and engages bottom 104 and the

sides

102, 103 slidably engage the sides of batten plate 110. Batten plate 110 is fastened to block 100 by means of screws 111.

Two

rectangular projections

112, 113 are fastened to lower plate 101, as by means of welding.

An upper slide plate 115 is provided with arched central portion 116 having a raised pad 117 and

upper side areas

118 and 119. The lower surface 120 of arched central portion 116 provides clearance for the sliding movement of upper slide plate 115 over batten plate 110.

Lower side areas

121 and 122 of plate 115 slidably engage lower plate 101. Two parallel longitudinal slots 124, 125 are provided in plate 115 so as to slidably engage, respectively,

projections

112 and 113.

Two

straps

127 and 128 overlie, respectively, slots 124 and 125.

Straps

127, 128 are fastened, respectively, to

projections

112, 113 as by means of screws 130.

A hinge pin 131 is fastened in raised pad 117 as by means of a drive fit or welding or the like.

ln this manner, the lower plate 101 and theupper plate 115 constitute an intermediate member between the saddle 40 and the adjacent guide rail section ends, whereby the ends are pivotally connected and supported in sliding movement by the intermediate member.

A plurality of

rail members

65, 65A, 65B, 65C, etc., are provided with tenter clip tracks or

paths

66, 67; 66A, 67A; 66B, 678, etc., respectively, and pivotal recesses 68, 68A, 683, etc., respectively, on one end and pivotal tongues 70, 70A, 70B, etc., respectively, on the opposite end. Pivotal tongues 70, 70A, 708, etc., are adapted to pivotally engage

hinge pins

131, 131A, 1318, etc., respectively, and lie in the respective pivotal recess. In this manner a continuous left side and a continuous right side rail member is provided as generally indicated by reference characters 72, 73, respectively. It will be observed that

guide rail members

65, 65A, 65B, etc., are provided with

projections

75, 76 which have, respectively, sliding weight-carrying

surfaces

75A, 76A supported upon upper plate 115.

FIG. 1 shows that the straight guide rail members or sections at the sheet or web receiving region and at the sheetdischarging region general use-con stitute one or more individual straight guide rail sections of a length normally greater than the length of the intermediate divergent straight guide rail sections.

The plurality of pivotally connected or hinged guide rail sections provide an infinite variety of curves. However, to types of curves are in general use -the hour glass, a reverse curve of equal and opposite contours, or the milk bottle contour curve, narrow at the neck and widening out. In either curve, sliding weight-carrying surfaces, 75A, 76A must be supported. As can be seen in FIG. 3, sliding weight-carrying surface 76A, at the angle shown, lies beyond a vertical plane Z parallel to the side of saddle 40 so that bearing surface 108 is unable to support sliding surface 76A in the absence of upper and lower sliding

plates

101 and 115.

FlGS. 7 and 8, illustrate a modified form of intermediate plate construction. The crossmember 17, the shaft 21, saddle 40, nut 61, are all constructed as previously described, with the exception of block 100. in F108. 7 and 8 block 100A is fastened to or integrally formed as part of saddle 40. Block 100A is provided with

dovetail grooves

150, 151.

An intermediate plate generally indicated by reference numeral 160 is provided with companion dovetail grooves 152, 153, and

side areas

154, 155 and a bottom surface 156.

lnterrnediate plate 160 is slidably mounted upon saddle 40 with bottom surface 156 slidably engaging bearing surface 108 and with

dovetail grooves

150, 152 and 151, 153, respectively, in sliding relationship to retain plate 160 upon saddle 40.

Hinge pin 131 is fastened in intermediate plate 160 for the purpose of pivotally connecting the adjacent ends of guide rail sections as previously described.

End caps 157 and 158 fastened to plate 160 as by screws 159 may be provided to limit the relative movement of intermediate plate 160 upon block 100A.

in FIG. 1, there is fragmentarily illustrated portions of tenter clip chains and 81 constituting tenter clips 82 pivotally connected together. The tenter clip chains 80, 81 rotate in tenter clip tracks 66, 67, respectively.

The tenter machine is provided with two driving sprockets 170, 171 and two driven sprockets 176, 177. Tenter chain 81 is operatively connected to sprockets 170, 171. Tcnter chain 80 is operatively connected to sprockets 171, 177. Tentering chains 80, 81 rotate in'the direction of arrows A" and respectively.

In operation the rotation of tenter chains 80, 81 in tenter clip tracks 66, 67, respectively, carry the web to be stretched from the sheet-receiving region of the tenter machine between sprockets 176, 177 to the delivery end or sheet-discharging region of the tenter machine between sprockets 170, 171.

Rotation of

hand wheels

22, 22A, 228, etc., cause the respective saddles 40, 40A, 408, etc., to slide upon

crossmembers

17, 17A, 178, etc., whereby the

rail members

65, 65A, 65B, etc., and their tenter clip tracks 66, 67; 66A, 67A; 66B, 678, etc., are moved in relation one to the other to provide a preselected path of movement for the respective clip chains 80, 81. That preselected path is under very close tolerance adjustment due to

threads

37, 38; 37A, 37B, etc., on shafts 21, 21A, etc,

The movement, induced by the turning of the

hand wheels

22, 22A, etc., acting through the sliding movement of the saddle 40 on the crossmember 17, changes the relative position of the hinge pin 131 in relation to the screw thread 38 in both lateral and longitudinal positions. In order to accommodate the changing relative position of the hinge pin, and consequently of the guide rail section ends pivotally connected to the hinge pin, there is now provided an intermediate plate 160 in the modified form illustrated in FIGS. 7 and 8 or plates 101, (shown in FIGS. 3, 4, 5 and 6) slidably mounted for telescoping support upon the saddle 40 and in turn supporting the guide rail section ends, as slide plates 101, 105 change relative position.

Having shown and described preferred embodiments of the present invention, by way of example, it should be realized that structural changes could be made and other examples given without departing from either the spirit or scope of this invention.

lclaim:

1. An expansion support platform for tenter machine guide rail sections comprising a frame, a plurality of crossmembers secured to said frame, a plurality of bearings, three for each crossmember, fastened to the ends and the center of each crossmember, a plurality of shafts, one for each crossmember, each shaft having a right-hand threaded section, a left-hand thread section, and a medial bearing area, said shafts rotatively mounted in said plurality of bearings with said medial bearing area located in the bearing fastened to the center of the crossmember, a plurality of hand wheels, means fastening a hand wheel to each of said plurality of shafts, a plurality of saddles, each saddle having a medially located block, two saddles for each crossmember, a plurality of nuts, one for each saddle, a nut secured in each saddle, one nut slidably mounting one saddle to a crossmember and to a right-hand thread section, another nut secured in another saddle slidably mounting the last-mentioned saddle to the last-mentioned crossmember and to the left-hand thread section of the same shaft, whereby rotation of the shaft in one direction draws the saddles toward each other and rotation of the shaft in an opposite direction separates said saddles, a plurality of lower plates, one for each saddle, means slidably mounting a lower plate to each saddle, a plurality of upper plates, one for each saddle means slidably mounting an upper plate to a lower plate, a plurality of hinge pins, one for each upper plate, means fastening a hinge pin to an upper plate, a plurality of guide rail sections, means pivotally mounting the end of one guide rail section to the end of the adjacent guide rail section through the hinge pin, thereby to support the end of one guide rail section and the end of the adjacent guide rail section upon the upper plate,

whereby, movement of the saddle moves the upper plate in telescoping relationship with the lower plate and the lower plate in telescoping relationship with a saddle, thereby to provide two pivotally connected and supported adjacent longitudinal tenter clip guide rail sections.

2. An expansion support plate form for tenter machine guide rail sections comprising a-frarne, a plurality of crossmembers fastened to said frame, a plurality of shafts, one for each crossmember, bearing means secured to said crossmembers, means secured to said crossmembers rotatively mounting said shafts to said crossmembers, each shaft having a left-hand thread and a right-hand thread, a plurality of saddles, two for and the othergroup of saddles being connected to the right hand threads through said nut means, to provide two saddles slidably mounted on each crossmember for movement toward and away from each other through rotation of the same shaft, a plurality of lower plates, one for each saddle, means slidably mounting a lower plate to each saddle, a plurality of upper plates, one vfor each saddle, means slidably mounting an upper plate to a lower plate, a plurality of hinge pins, one for each upper plate, means fastening a hinge pin to an upper plate, a plurality of guide rail sections, means pivotally mounting the end of one guide rail section to the end of the adjacent guide rail section through the hinge pin, thereby, to support the end of one guide rail section and the end of the adjacent guide rail section upon the upper plate, whereby, movement of the sad-.

dle moves the upper plate in telescoping relationship with the lower plate and the lower plate in telescoping relationship with the saddle, to provide twopivotally connected and supported adjacent longitudinal tenter clip guide rail sections.

3. An expansion support platform for tenter machine guide rail sections consisting of a tenter machine having a plurality of crossmembers and a plurality'of saddles, two for each crossmember, means slidably mounting said saddles to said crossmembers, a plurality of shafts, onefor each crossmember,

each shaft having a left-hand threaded and a right-hand, bearing means rotatively mounting said shafts to said crossmembers, said saddles being divided into two groups, means slidablyeonnecting each saddle in one group to the left-hand threads and means slidably connecting each saddle in the other group to the right-hand threads, to provide two saddles slidably mounted on each crossmember for movement toward and away from each other through rotation of the same shaft, a plurality of lower plates, one for each saddle, means slidably mounting a lower plate to each saddle, a plurality of upper plates, one for each saddle, means slidably mounting an upper plate to a lower plate, a plurality of hinge pins,-one for each ,upper plate, means fastening a hinge pin to an upper plate, a

plurality of guide rail sections, each guide rail section having a tenter clip guide surface, means pivotally connecting adjacent ends of said guide rail sections'to each other through said hinge pins, said adjacent ends slidingly engaging said upper plates, whereby the tenter clip guidesurfaces form continuous tenter clip paths, the guide rail sections comprising straight sections of such length to produce curved guide paths for tenter clips, said shafts controlling the contour of said paths through said saddles and the relative position of the lower plates upon the saddles and the relative position of the upper said recess, means fast'ening said batten plate to said block. an upper plate provided with upper side areas, and two parallel longitudinal slots, two parallel projections provided upon said lower plate, said upper plate slidably mounted upon said lower plate with said two parallel projections located respectively, in said two parallel longitudinal slots to limit and guide the sliding movement of said upper plate upon said lower plate, two straps, means fastening, respectively, said two straps to said two parallel projections to slidably retain the upper plate in relation to the lower plate, a hinge pin, means fastening said hinge pin to said upper plate, thereby to pivotally connect ad-..

jacent ends of guide rail sections and to support adjacent ends of guide rail sections upon said upper side areas.

5. An expansion support platform for tenter machine guide rail sections consisting of a tenter machine having a crossmember and a saddle, means slidably mounting said saddle to said crossmember formovement back and forth across said crossmember, a block provided with two oppositely located and parallel grooves having, respectively, parallel guide edges, an intermediate plate having complementary two oppositely located and parallel grooves having, respectively, two parallel guide edges. said last mentioned two parallel guide edges slidingly engaging said first mentioned two oppositely located and parallel grooves and said first mentioned parallel guide edges slidingly engaging said last mentioned two oppositely located and parallel grooves, and a hinge pin, means fastening said hinge pin to said intermediate plate, thereby to pivotally connect adjacent endsof guide-rail sections and to support adjacent ends of guide rail sections upon an intermediate plate.

6. An expansion support platform for tenter machine guide rail sections consisting of a tenter machine having a plurality of crossmembers and a plurality of saddles two for each crossmember, means slidably mounting said saddles to said crossmembers, a plurality of shafts, one for each crossmember, each shaft having a left-hand thread and a right-hand thread, bearing means rotatively mounting said shafts to said crossmembers, said saddles being divided into two groups, means slidably connecting each saddle in'one group to the left-hand threads, and means slidably connecting each saddle in the other group to the right-hand threads, to provide two saddles slidably mounted on each crossmember for movement toward and away from each other through rotation of the same shaft, a plurality of blocks fastened to said plurality of saddles, one block for each saddle, a plurality of intermediate plates, one for each block, means slidingly mounting an intermediate plate to a block, a plurality of hinge pins, one for each intermediate plate, means fastening a hinge pin to an upper plate, a plurality of guide rail sections, each guide rail section having a tenter clip track, means pivotally'connecting adjacent ends of said guide rail sections to each other through said hinge pins, said adjacent ends slidingly engaging an intermediate plate.

Claims

1. An expansion support platform for tenter machine guide rail sections comprising a frame, a plurality of crossmembers secured to said frame, a plurality of bearings, three for each crossmember, fastened to the ends and the center of each crossmember, a plurality of shafts, one for each crossmember, each shaft having a right-hand threaded section, a left-hand thread section, and a medial bearing area, said shafts rotatively mounted in said plurality of bearings with said medial bearing area located in the bearing fastened to the center of the crossmember, a plurality of hand wheels, means fastening a hand wheel to each of said plurality of shafts, a plurality of saddles, each saddle having a medially located block, two saddles for each crossmember, a plurality of nuts, one for each saddle, a nut secured in each saddle, one nut slidably mounting one saddle to a crossmember and to a right-hand thread section, another nut secured in another saddle slidably mounting the last-mentioned saddle to the last-mentioned crossmember and to the left-hand thread section of the same shaft, whereby rotation of the shaft in one direction draws the saddles toward each other and rotation of the shaft in an opposite direction separates said saddles, a plurality of lower plates, one for each saddle, means slidably mounting a lower plate to each saddle, a plurality of upper plates, one for each saddle means slidably mounting an upper plate to a lower plate, a plurality of hinge pins, one for each upper plate, means fastening a hinge pin to an upper plate, a plurality of guide rail sections, means pivotally mounting the end of one guide rail section to the end of the adjacent guide rail section through the hinge pin, thereby to support the end of one guide rail section and the end of the adjacent guide rail section upon the upper plate, whereby, movement of the saddle moves the upper plate in telescoping relationship with the lower plate and the lower plate in telescoping relationship with a saddle, thereby to provide two pivotally connected and supported adjacent longitudinal tenter clip guide rail sections.

2. An expansion support plate form for tenter machine guide rail sections comprising a frame, a plurality of crossmembers fastened to said frame, a plurality of shafts, one for each crossmember, bearing means secured to said crossmembers, means secured to said crossmembers rotatively mounting said shafts to said crossmembers, each shaft having a left-hand thread and a right-hand thread, a plurality of saddles, two for each crossmember, means slidably mounting said saddles to said crossmembers, nut means provided in each saddle, said saddles divided into two groups, one group of saddles being connected to the left-hand threads through said nut means, and the other group of saddles being connected to the right-hand threads through said nut means, to provide two saddles slidably mounted on each crossmember for movement toward and away from each other through rotation of the same shaft, a plurality of lower plates, one for each saddle, means slidably mounting a lower plate to each saddle, a plurality of upper plates, one for each saddle, means slidably mounting an upper plate to a lower plate, a plurality of hinge pins, one for each upper plate, means fastening a hinge pin to an upper plate, a plurality of guide rail sections, means pivotally mounting the end of one guide rail section to the end of the adjacent guide rail section through the hinge pin, thereby, to support the end of one guide rail section and the end of the adjacent guide rail section upon the upper plate, whereby, movement of the saddle moves the upper plate in telescoping relationship with the lower plate and the lower plate in telescoping relationship with the saddle, to provide two pivotally connected and supported adjacent longitudinal tenter clip guide rail sections.

3. An expansion support platform for tenter machine guide rail sections consisting of a tenter machine having a plurality of crossmembers and a plurality of saddles, two for each crossmember, means slidably mounting said saddles to said crossmembers, a plurality of shafts, one for each crossmember, each shaft having a left-hand threaded and a right-hand, bearing means rotatively mounting said shafts to said crossmembers, said saddles Being divided into two groups, means slidably connecting each saddle in one group to the left-hand threads and means slidably connecting each saddle in the other group to the right-hand threads, to provide two saddles slidably mounted on each crossmember for movement toward and away from each other through rotation of the same shaft, a plurality of lower plates, one for each saddle, means slidably mounting a lower plate to each saddle, a plurality of upper plates, one for each saddle, means slidably mounting an upper plate to a lower plate, a plurality of hinge pins, one for each upper plate, means fastening a hinge pin to an upper plate, a plurality of guide rail sections, each guide rail section having a tenter clip guide surface, means pivotally connecting adjacent ends of said guide rail sections to each other through said hinge pins, said adjacent ends slidingly engaging said upper plates, whereby the tenter clip guide surfaces form continuous tenter clip paths, the guide rail sections comprising straight sections of such length to produce curved guide paths for tenter clips, said shafts controlling the contour of said paths through said saddles and the relative position of the lower plates upon the saddles and the relative position of the upper plates upon the lower plates.

4. An expansion support platform for tenter machine guide rail sections consisting of a tenter machine having a crossmember and a saddle, means slidably mounting said saddle to said crossmember for movement back and forth across said crossmember, a block, means fastening said block to said saddle, a lower plate having a recess and an opening, said lower plate slidably mounted upon said saddle with said block located in said opening to guide and limit the movement of said lower plate upon said saddle, a batten plate, located in said recess, means fastening said batten plate to said block, an upper plate provided with upper side areas, and two parallel longitudinal slots, two parallel projections provided upon said lower plate, said upper plate slidably mounted upon said lower plate with said two parallel projections located respectively, in said two parallel longitudinal slots to limit and guide the sliding movement of said upper plate upon said lower plate, two straps, means fastening, respectively, said two straps to said two parallel projections to slidably retain the upper plate in relation to the lower plate, a hinge pin, means fastening said hinge pin to said upper plate, thereby to pivotally connect adjacent ends of guide rail sections and to support adjacent ends of guide rail sections upon said upper side areas.

5. An expansion support platform for tenter machine guide rail sections consisting of a tenter machine having a crossmember and a saddle, means slidably mounting said saddle to said crossmember for movement back and forth across said crossmember, a block provided with two oppositely located and parallel grooves having, respectively, parallel guide edges, an intermediate plate having complementary two oppositely located and parallel grooves having, respectively, two parallel guide edges, said last mentioned two parallel guide edges slidingly engaging said first mentioned two oppositely located and parallel grooves and said first mentioned parallel guide edges slidingly engaging said last mentioned two oppositely located and parallel grooves, and a hinge pin, means fastening said hinge pin to said intermediate plate, thereby to pivotally connect adjacent ends of guide rail sections and to support adjacent ends of guide rail sections upon an intermediate plate.

6. An expansion support platform for tenter machine guide rail sections consisting of a tenter machine having a plurality of crossmembers and a plurality of saddles two for each crossmember, means slidably mounting said saddles to said crossmembers, a plurality of shafts, one for each crossmember, each shaft having a left-hand thread and a right-hand thread, bearing means rotatively mounting said shafts to said crossmembers, saId saddles being divided into two groups, means slidably connecting each saddle in one group to the left-hand threads, and means slidably connecting each saddle in the other group to the right-hand threads, to provide two saddles slidably mounted on each crossmember for movement toward and away from each other through rotation of the same shaft, a plurality of blocks fastened to said plurality of saddles, one block for each saddle, a plurality of intermediate plates, one for each block, means slidingly mounting an intermediate plate to a block, a plurality of hinge pins, one for each intermediate plate, means fastening a hinge pin to an upper plate, a plurality of guide rail sections, each guide rail section having a tenter clip track, means pivotally connecting adjacent ends of said guide rail sections to each other through said hinge pins, said adjacent ends slidingly engaging an intermediate plate.