US3168954A

US3168954A - Hanger for flexible sheet material

Info

Publication number: US3168954A
Application number: US250581A
Authority: US
Inventors: Herrmann Pieter Von
Original assignee: Mohawk Precision Corp
Current assignee: Mohawk Precision Corp
Priority date: 1963-01-10
Filing date: 1963-01-10
Publication date: 1965-02-09
Anticipated expiration: 1982-02-09

Description

Feb. 9, 1965 P. VON HERRMANN HANGER FOR FLEXIBLE snss'r. MATERIAL Filed Jan. 10, 1963 United States Patent ()filice 3,168,954 Patented Feb. 9, 1965 3,168,954 HANGER FOR FLEXIBLE SHEET MATERIAL Pieter von Herrmann, Schenectady, N.Y., assignor to lxlgdoll awk Precision Corporation, a corporation of New Filed Jan. 10, 1963, Ser. No. 256,531 11 Claims. (Cl. 211-50) This invention relates to an improved hanger for holding and releasing flexible sheet material of various thicknesses, especially sheets of paper or tablets which may be held alongside one another.

Various types of devices are known for holding material, in which the material is inserted upward to displace a movable body, which thereafter provides a wedging action under the weight of the material to hold it in place. When such devices take the form of elongated members for holding flat flexible sheet material such as paper, the wedging members, if more than one, are often connected together in some fashion to hold them aligned and to prevent their jamming or becoming dislodged. The interconnection may also take the form of a release mechanism, which can serve to lift the wedging members so as to release the flexible sheet material. One example of the foregoing type of paperholder may be seen in Swiss Patent 278,129 issued to Walter Hess on January 3, 1952. One disadvantage of the foregoing type of construction is that the releasing mechanism lifts all of the wedging pieces at once and, in the event that it is desired to hold groups of sheets of different thickness, such as a tablet or a collection of sheets alongside a single sheet, it may be found that the thickness of the tablet may prevent the single sheet from being held satisfactorily. Similarly, the interconnection holding the wedging members in alignment may bring about the release of all the sheets at once, when other types of releasing devices than the one described above are used.

Various other inadequacies have been noted in prior art hangers, such as design which allows the improper insertion of the material to be retained, and failure to recognize the true significance of certain dimensions and angles contributing to proper operation of such devices.

Accordingly, one object of the present invention is to provide an improved hanger for flexible sheet material in which various thicknesses of material may be held alongside one another and separately released without disturbing adjoining sheets.

Another object of the invention is to provide a simplified hanger for flexible sheet material employing a number of independently functioning wedging members requiring no additional parts for the aligning or releasing mechanism.

Still another object of the invention is to provide an improved hanger for flexible sheet material which uses a minimum of parts.

Another object of the invention is to provide an improved hanger for flexible sheet material designed to facilitate proper insertion of the material.

Yet another object of the invention is to provide an improved hanger employing components having particular and optimum shape which gives improved results in holding and releasing flexible sheet material.

These and many other objects of the invention will become apparent in the concluding portion of the specification, taken together with the accompanying drawings, in which:

FIG. 1 is a perspective view of one form of my improved hanger illustrating various aspects of its operation,

FIG. 2 is an enlarged cross-sectional view of a hanger similar to the hanger shown in FIG. 1,

of my invention will be explained.

FIG. 2a is a fragmentary cross-sectional view of the basic hanger shape of FIG. 2, illustrating the release mechanism,

FIG. 3 is a modified form of the hanger, shown in enlarged cross-section, and,

FIGS. 4 and 5 are perspective views illustrating still other types of wedging members which might be employed.

Briefly stated, the invention is practiced by providing an elongated member with downwardly converging front and rear walls which are spaced from one another to leave an open mouth for the insertion of flexible sheet material behind a wedging piece which rests loosely between the walls. The wedging members are independently functioning, and to accomplish this, the front and rear walls are joined by a specially shaped top wall with a portion projecting into the recess which prevents jamming or misalignment of the wedging members, while allowing room for insertion of a substantial thickness of sheet material. The lower edge of the front wall terminates at a selected location, so as to allow independent release of each wedging piece by pulling the flexible sheet material forward at an angle against it.

Referring now to FIG. 1 of the drawing, the hanger comprises an elongated member 1 having a substantially flat vertical rear wall 2, a concave or indented top wall 3, and a slanting front wall 4. The elongated member 1 is adapted for aflixing to the wall or other supporting member in a horizontal position by screws, for example, (not shown) passing through mounting holes 5.

Member 1 is preferably an integral piece of uniform cross-section and may be conveniently manufactured in any desired length by extruding metal such as aluminum through a die. A number of metal rollers 6 are disposed end-to-end between rear wall 2 and front wall 4.

In FIGS. 1 and 2, the wedging members 6 are cylindrical metal rollers of a suitable length and preferably 'made of stainless steel. The front wall 4 may be notched and bent over, as shown at '7, to prevent rollers 6 from coming out at the ends, yet allowing a sheet behind roller 6 to extend beyond the end of member 1. Other retaining means similar to tab 7 will be apparent to those skilled in the art.

FIG. 1 shows a single sheet of flexible material 8, such as paper, adjacent a collection or pad of sheets 9 of substantial thickness. Another sheet of paper 10 is shown in proper position for withdrawing it from the hanger.

Referring now to FIG. 2 of the drawing, other features It will be seen that rear, top, and

front walls

2, 3 and 4 respectively together enclose an elongated recess 11 having an open mouth 12 at the bottom. Front wall 4 converges downwardly toward rear wall 2 at an angle A, and terminals at an edge 4a. Each roller 6 rests loosely between

walls

2, 4 in the position shown, above mouth 12 of the recess.

The top wall 3 has a horizontally extending portion 3a, a vertically extending portion 311, and another horizon- .tally extending portion 30, so as to provide an indentation or constriction extending into recess 11 between

walls

2, 4. It should be particularly noted that the constriction afforded by concave top wall 3 allows the recess 11 to accommodate only one roller 6 at a given location. This is indicated in FIG. 2 by the interference which would exist if another roller 6 attempted to pass longitudinally through the recess 11 past roller 6. The concavity of top wall 3 affords a place for roller 6 to move upward along the front wall when a considerable thickness or sheet material is inserted behind the roller, while also providing a subrecess 11a to accommodate the projecting end of the sheet material. Subrecess 11a allows room for the projecting end of the sheet to extend upward a considerable distance along the back wall. This extra length is useful, because it permits the sheet to travel back downward while the wedging action is taking place.

It will be apparent that some variations can exist in the shape of the top wall without departing from the inventive concept. For example, the top wall could be formed as shown in FIG. 3 (to be discussed later) to provide the functions of the concave top wall.

The wedging action provided by each roller 6 is partly dependent upon the following coefficients of friction: between roller 6 and front wall 4 at point 13; between roller 6 and sheet 8 at point 14, and between sheet 8 and rear wall 2 at point 15. It can be shown mathematically, that slippage will occur, for any given force on the sheet, when the least of these coefficients at points 13, 14 or 15 is less than the tangent of angle A/ 2 (neglecting the small effect of roller weight). Thus the angle A of convergence between front and rear wall is selected with regard to the material and surface finish of the parts and the type of sheet material to be held, so that the tangent of A/ 2 is comfortably less than the lowest coefiicient of friction to be expected. Yet the angle should not be so small as to preclude release of the sheets as will be described in connection with FIG. 2a. I have found that for an extruded aluminum member 1, using a semipolished aluminum or stainless steel roller 6 for holding most types of paper, satisfactory results are achieved with an angle A on the order of 19 22.

FIG. 2a illustrates the proper criteria of design for release of the sheet material Without the need for a lifting rod or other such interconnecting member between the wedging members. It will be observed that when a piece of sheet material 10 is being held by roller 6, the closest point of approach of roller 6 to rear wall 2 is at point 16. Accordingly, the lower edge 4a of the slanting front wall 4 is caused to terminate at such a point that a line extending from the lower edge 4a through the point of closest approach 16 will leave a portion 6a of roller 6 extending downwardly below this line. Therefore when a sheet of material 10 is flexed and pulled, as indicated, an upward force depicted by vector 17 will be exerted on portion 6a to lift the roller 6 and release sheet 10.

FIG. 3 illustrates the various aspects of a modified form of my invention. First, the wedging members may also be hollow rollers, as shown at 18. The reduced weight of hollow rollers has little effect on the operation and may offer a more economical construction.

Secondly, it will be observed that the rear wall 2 is modified to have an outwardly projecting portion 19, which provides a contoured surface 19a serving to smoothly guide an inserted sheet 20 behind roller 18. The function of the contoured projecting portion 19 is to force the user to insert sheet 20 at an angle to thevertical, to prevent inadvertent insertion of sheet 20 in front of the roller 18. Having thus forced insertion of the sheet at an angle, the contoured surface 19a redirects the sheet and smoothly guides it into the proper position behind roller 18.

Thirdly, the top wall 21 is equivalent in its operation to the concave wall 3 of FIG. 2. Top wall 21 has a flat section

21a connecting walls

2, 4 and includes an integral projecting portion or rib 21b extending into recess 11 to constrict it. Rib 21b prevents one roller 18 from passing another roller as before, yet leaves a subrecess along the back wall for the projecting end of the sheet.

FIG. 4 illustrates that the wedging members need not be elongated, but may also be spherical in shape, such as the balls 22 held in recess 11 by means of the slightly modified turned over tab 7a. The use of balls 22 made provide economy in some cases, and provide advantages where fairly small sheets are to be held side-by-side, such as an arrangement of photographs.

FIG. illustrates another modification of the invention and is intended to show that the wedging members need not have a round cross-section. Here, substantially tri-- angular or kidney-shaped wedging members 23 may be extruded and cut in short lengths. They may include a hollow recess 23a to reduce the amount of metal required. An extending lower lip 23b serves the same function as portion 6a in FIG. 2a and may provide improved releasing action for some applications, such as when relatively stiff material such as cardboard is to be held. Piece 23 should be designed so that the cross-section converges immediately below the opposite points of

contact

24, 25 at an angle which is less than. angle A. This will provide clearance for the release of the member when lip 23b is forced outward by the sheet.

The operation of the invention will be better understood by reference to the perspective view of FIG. 1. First it will be observed that my improved hanger is capable of handling many greatly varying thicknesses of material side-by-s'ide simultaneously. The rollers 6 will seek various levels independently of one another, as illustrated by the differences in level of rollers holding single sheet 8 and tablet 9. The rollers are completely unconnected from one another and operate separately by virtue of the constriction in the recess. It will be observed (FIGS. 2 and 3) that the specially shaped top wall forces the roller toward the front and still allows a substantial thickness of material to be inserted into subrecess 11a.

It will also be observed from FIG. 1 that release of sheet 10 can be accomplished without disturbing sheets 8 or 9. The rollers holding sheet 10 can move upward independently when the sheet is flexed and pulled in the manner indicated in FIG. 20. Again, the releasing mechanism does not cause all of the rollers to release, but only the rollers holding sheet 10. The design of the hanger to provide release of independently functioning rollers as in FIG. 2a, and selection of the shape of the top wall with due regard to the shape of the wedging member employed so that the recess will accommodate only one wedging member at any one location, combine to provide a great improvement over prior art hangers. Of course, it will be understood that various shapes of wedging members might be employed once the principle of the invention is understood, and that any of the above features might be used in conjunction with the modified rear wall depicted in FIG. 3.

While the preferred embodiment of the invention and several modifications thereof have been described, various other modifications may become apparent to those skilled in the art and it is desired to cover by the appended claims, all such modifications as fall within the true spirit and scope of the invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

l. A hanger for flexible sheet material comprising an elongated member adapted for mounting horizontally and having spaced downwardly convergent front and rear walls connected by a top wall to define an elongated recess having an open mouth at the bottom for the insertion of flexible sheet material, a plurality of separate unconnected wedging pieces disposed longitudinally inside the recess between front and rear walls, said top wall having a portion extending longitudinally along the length of the member and projecting inwardly between front and rear walls to longitudinally divide the upper portion of the recess and also projecting sufiiciently to prevent any one of said wedging pieces from moving longitudinally along the recess past another wedging piece, whereby said wedging pieces function independently to grip various thicknesses of sheet material inserted between the wedging pieces and the wall without disturbing the functioning of' other wedging pieces.

2. A hanger for flexible sheet material comprising an elongated member adapted for mounting in a horizontal position and having a substantially vertical rear wall and a spaced downwardly convergent front wall connected thereto by a top wall, said walls being substantially rigid and together defining an elongated recess having an open mouth at the bottom for the insertion of flexible sheet material, a plurality of unconnected wedging pieces disposed longitudinally inside the recess between front and rear walls to provide a wedging action to hold sheet material inserted between said wedging pieces and the rear wall, each of said wedging pieces also having a portion projecting downwardly beyond a line which extends from the lower edge of said front wall through the point of closest approach of the wedging piece .to the rear wall, whereby the sheet material may be flexed and pulled against stud projecting portion to provide an upward releasing force on the wedging piece, said top wall including a portion extending longitudinally along the length of the member and projecting inwardly between front and rear walls to longitudinally divide the upper portion of the recess and projecting sufficiently so that the recess will accommodate only one of the wedging pieces at any location, whereby no means of interconnection prevents independent functioning of the wedging pieces in holding or releasing various thicknesses of sheet material.

3. The combination according to claim 2, wherein said top wall is indented along its length toward said recess so that the indented portion serves as the longitudinally dividing top wall portion.

4. The combination according to claim 2, wherein said top wall includes an integral rib extending into said recess so that the rib serves as the longitudinally dividing top wall portion.

5. The combination according to claim 2, wherein the front and rear walls converge at an angle which is selected so that the tangent of one half of said angle is less than the coeflicient of friction between the wedging piece and the sheet material.

6. The combination according to claim 2, wherein said wedging pieces comprise cylindrical rods, and wherein said elongated member is an aluminum extrusion whose front and rear walls converge at an angle on the order of 19 to 22.

7. The combination according to claim 2, wherein said rear wall defines a contoured protrusion located below the mouth of said recess and arranged to guide the sheet material upwardly along the rear wall into the mouth of the recess when the sheet material is inserted at an angle to the rear wall against said protrusion.

8. The combination according to claim 2, wherein said wedging pieces comprise substantially spherical elements.

9. A hanger for flexible sheet material comprising an elongated extruded member of uniform cross section adapted for mounting in a horizontal position and having a substantially vertical rear wall and an integral top and front wall, said walls being substantially rigid and defining an elongated recess having an open mouth at the bot tom thereof for the insertion of flexible sheet material, said top wall having a reverse curve therein to cause it to extend into and longitudinally divide the top portion of said recess into longitudinal subrecesses, said front wall being substantially flat and converging downwardly toward the rear wall at an included angle on the order of 19-Z2, a plurality of substantially cylindrical unconnected rollers disposed longitudinally along the member and resting loosely between said front and rear walls but having a diameter too great to come out of the mouth of the recess or to move longitudinally past one another in the constricted recess. said front wall being of such a selected length that portions of the rollers protrude downwardly past a line which extends from the lowest edge of the front wall through the point of closest approach of the rollers to the rear wall.

10. In an elongated hanger of the type having spaced first and second downwardly converging substantially rigid walls defining an elongated recess with an open mouth at the bottom and a plurality of rollers disposed between said walls so as to grip sheet material inserted into the mouth of the recess, the improvement comprising: an elongated wall portion extending longitudinally along the length of the member and projecting into said recess between said walls to longitudinally divide the recess and extending sufficiently into the recess so that one roller cannot move longitudinally past another, the lengths of said first and second converging walls being selected so that portions of said rollers extend downward below a line which extends from the point at which the sheet material is gripped against the first wall to the lower terminating edge of the second wall, whereby said rollers may be unconnected and may function independently in gripping and releasing various thicknesses of sheet material.

11. A hanger for flexible sheet material comprising an elongated member adapted for mounting in a horizontal position and having a substantially vertical rear wall and a spaced downwardly convergent front wall connected thereto by a top wall, said walls together defining an elongated recess havingan open mouth at the bottom for the insertion of flexible sheet material, a plurality of unconnected wedging pieces disposed longitudinally inside the recess between front and rear walls to provide a wedging action to hold sheet material inserted between said wedging pieces and the rear wall, each of said wedging pieces being substantially triangular in cross-section and disposed in the recess with one end of the triangle extending beyond the mouth of the recess to facilitate guiding the sheet material behind its said triangle end comprising a portion projecting downwardly beyond a line which extends from the lower edge of said front wall through the point of closest approach of the wedging piece to the rear wall, whereby the sheet material may be flexed and pulled against said projecting triangle end portion to provide an upward releasing force on the wedging piece, said top wall including a portion extending inwardly between front and rear walls to constrict the recess so that it will accommodate only one of the wedging pieces at any lobation, whereby no means of interconnection prevents independent functioning of the wedging pieces in holding or releasing various thicknesses of sheet material.

References Cited by the Examiner

UNITED STATES PATENTS

2,3 88,297 11/45 Slaughter 16 l3 8 2,521,604 9/5 0 Provost 24244 3,063,569 11/ 63 Huber 211-89 FOREIGN PATENTS 477,102 12/ 37 Great Britain. 197,609 5/58 Austria.

CLAUDE A. LE ROY, Primary Examiner.

Claims

1. A HANGER FOR FLEXIBLE SHEET MATERIAL COMPRISING AN ELONGATED MEMBER ADAPTED FOR MOUNTING HORIZONTALLY AND HAVING SPACED DOWNWARDLY CONVERGENT FRONT AND REAR WALLS CONNECTED BY A TOP WALL TO DEFINE AN ELONGATED RECESS HAVING AN OPEN MOUTH AT THE BOTTOM FOR THE INSERTION OF FLEXIBLE SHEET MATERIAL, A PLURALITY OF SEPARATE UNCONNECTED WEDGING PIECES DISPOSED LONGITUDINALLY INSIDE THE RECESS BETWEEN FRONT AND REAR WALLS, SAID TOP WALL HAVING A PORTION EXTENDING LONGITUDINALLY ALONG THE LENGTH OF THE MEMBER AND PROJECTING INWARDLY BETWEEN FRONT AND REAR WALLS TO LONGITUDINALLY DIVIDE THE UPPER PORTION OF THE RECESS AND ALSO PROJECTING SUFFICIENTLY TO PREVENT ANY ONE OF SAID WEDGING PIECES FROM MOVING LONGITUDINALLY ALONG THE RECESS PAST ANOTHER WEDGING PIECE, WHEREBY SAID WEDGING PIECES FUNCTION INDEPENDENTLY TO GRIP VARIOUS THICKNESSES OF SHEET MATERIAL INSERTED BETWEEN THE WEDGING PIECES AND THE WALL WITHOUT DISTURBING THE FUNCTIONING OF OTHER WEDGING PIECES.