US3729187A

US3729187A - Sheet handling device

Info

Publication number: US3729187A
Application number: US00181456A
Authority: US
Inventors: H Waibel
Original assignee: Singer Co
Current assignee: Singer Co
Priority date: 1971-09-17
Filing date: 1971-09-17
Publication date: 1973-04-24
Anticipated expiration: 1990-04-24

Abstract

A sheet handling device for changing the feed direction of a conveyed sheet. A hub secured axially on a rotatable shaft has a plurality of gripping members pivotable in different radial planes disposed thereabout. Each gripping member has a finger portion engageable with a cylindrical sheet guiding surface portion of the hub, and a camming portion engageable with a camming race on a stationary block. A garter spring biases each gripping finger toward the sheet guiding surface to grip the edge of the sheet therebetween. The camming portion and race bias each gripping finger away from the sheet guiding surface over a predetermined angular path. As the hub is rotated, the spring causes successive finger portions to grip the sheet and convey it along a curved path through a predetermined angle. Thereafter, the action of the race on the camming portion of successive fingers causes the sheet to be released in a predetermined exit direction.

Description

[ll] 3,729,187 1 Apr. 24, 19 73 United State s Patent 91 Waibel v 1' SHEET HANDLING DEVICE Primary Examiner- EdWard A. Sroka Attorney-Warren P. Kujawa et al.

lnventor: Helmut K. Waibel, San Leandro,

Calif.

Assignee: The Singer Company, New York,

' direction of a conveyed sheet. A hub secured axially [22] Fled: 7 Sept 1971 on a rotatable shaft has a plurality of gripping mem- App], 1 1,45 bers ivotable in different radial planes disposed thereahout. Each gripping member has a finger portion cngageablc with a cylindrical sheet guiding surface portion of the hub, and a camming portion engageuble with a camming race on a stationary block. A garter spring biases each gripping finger toward the sheet guiding surface to grip the edge of the sheet therebetween. The camming portion and race bias '[52] US. [5 l .B65 h 5/06, B65h 29/06 I [58] Field of Search...................

Int.

[56] References Cited each gripping finger away'from the sheet guiding surface over a predetermined angular path. As the hub is rotated, the spring causes successive finger portions to 101/409 X grip the sheet and convey it along a curved path 101/409 X a through a predetermined angle. Thereafter, the action 271/82 of the race on the camming portion of successive fingers causes the sheet to be released in a predetermined exit direction.

s T m m N H u E m m T m m A m. m P mmqm S mLmm m m A .mwnn T mm om S 885? D E 8387 T 1 .I. 9999 N HHHH U 5596 19, Claims, 8 Drawing Figures Patented April 24, 1973 3,729,187

3 Sheets-Sheet l INVENTOR.

. u mama %%dib@z BY Q WWW/A? Patented April 24, 1973 5 Sheets-Sheet 2 SHEET HANDLING DEVICE BACKGROUND OF THE INVENTION 1 Field of the Invention This invention relates to sheet handling devices for conveying flat flexible sheets along a desired multidirectional path. More particularly, this invention relates to devices for changing the direction of feed of such'conveyed sheets.

2. Description of the Prior-Art Many sheet feeding devices are known which are employed in various machines to convey documents or similar flat flexible sheets along a desired feed path. In many applications, a sheet feeding device is required which is capable of accepting a sheet already being conveyed in a first direction and positively feeding it in a second direction different from the first direction. In some electrostatic copiers, e.g. such as that disclosed in US. Pat. No. 3,600,082 issued Aug. 17, 1971, a copy sheet turnaround station is utilized to positively feed a copy sheet, which is already traveling in a first direction past an image transfer station, upwardly and in a reverse direction toward an image fusing station. While the copy sheet turnaround station disclosed in the referenced patent utilizes a vacuum drum for liftingand reversing the feed direction of the copy sheet, other mechanisms are known in the art for accomplishing this same result. In addition, this and other similar types of sheet feeding devices have been employed in a wide variety of other environments than copy machines, such asdocument sorting devices,.paper coating machines, film threading devices, etc.

SUMMARY OF THE INVENTION The invention comprises a sheet feeding device of the above-described type which is inexpensive to manufacture, highly reliable in performance, and readily adaptable to a wide variety of uses. The preferred embodiment includes a hub secured axially on a rotatable shaft and having a substantially cylindrical sheet guiding surface. A plurality of gripping members are pivotally mounted on the hub about the axis of the shaft in different substantiallyradial planes. Each gripping member has a finger portion with a surface engageable with the sheet guiding surface for gripping a sheet therebetween and a camming portion engageable with acamming race on a stationary camming block. A garter spring coupled to each gripping member biases the gripping fingers toward the sheet guiding surface. The camming portion and race bias each gripping finger away from the sheet guiding surface over a predetermined angular path.

In operation, as the hub rotates, the garter spring causes successive finger portions to grip the edge of an introduced sheet and convey it along a curved path through a predetermined angle. Thereafter, the action of the race on the camming portion of successive fingers releases the sheet for further travel in the exit direction.

In an alternate embodiment, the hub and camming block are adjustably mounted to accommodate sheets of different widths.

For a further understanding of the nature and advantages of theinvention, reference should be had to the ensuing detailed description taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view'of a preferred embodiment of the invention;

FIG. 2 is a sectional view taken along line 2--2 of FIG. 1;

FIG. 3 is a perspective view, partially exploded, illustrating the hub assembly elements;

FIG. 4 is a sectional view taken along line 4-4 of I DESCRIPTION OF THE PREFERRED EMBODIMENTS Turning now to the drawings, FIG. 1 illustrates a preferred embodiment of the invention which is supported in a main frame generally indicated by the reference numeral 10 and having a pair of side plates ll, 12 structurally interconnected by upper and lower front brace members l3, l4 and rear brace member 15 (shown in FIG. 2). Attached to lower front brace member 14 by means of screws 16 is an entrance platform 18 having a sheet squaring guide 19 for properly aligning an entering sheet 20 which enters the preferred embodiment in the direction of arrow 2l. Attached to upper. front brace member l3.by means of screws 22 is an exit platform 23 for supporting an exiting sheet.

Mounted in the rear of main frame 10 is a sheet handling device for positively lifting and feeding flexible sheet 20 in an exit direction which is substantially the reverse of the entrance direction 21. With reference to FIGS. 1 and 2, a shaft 25 is journaled in a pair of

bearings

26, 27 mounted in

side plates

11, 12, respectively. A gear 28 is secured to one end of shaft 24 forv providing power transfer from a suitable power source (not shown) to shafts 25 in order to rotate shaft 25 and the elements secured thereto (described below) in the direction of arrows 29. l

Secured at both ends of shaft 25 by means of screws 31 tightened onto axially extending flats 32 are a pair of identical hub assemblies 35. As best seen in FIGS. 2 and 3, each hub assembly includes a hub 36 having a substantially cylindrical body portion 37, a central annular portion 38 and an inner annular portion39 having a knurled'sheet guiding surface 40. Extending radially from a plurality of equiangularly disposed locations on the outer surface of annular portion 38 are a number of irregularly shaped boss members 41 each having a pivot pin bore 42 and a radial slot 43 which extends into annular portion 38. Hub 36 may be constructed by molding from a plastic material, machining from a suitable metal (e.g., aluminum) or in any other manner known to those skilled in the art.

Pivotally mounted in each slot 43 is a gripping member 44 having a bore 45 for receiving a pivot pin 46 and an aperture 47 for accommodating a garter spring 48. Each gripping member 44 has a finger portion 50 engageable with knurled surface 40 for gripping the edge portion of a sheet therebetween, and a camming portion 52 engageable with a camming surface described below. Identical gripping members 44 are preferably stamped from a suitable material (e.g. steel or plastic).

To assemble, each gripping member 44 is positioned in the corresponding slot 43 with bore 45 aligned with pivot pin bore 42, after each pivot pin 46 is inserted into the aligned bores. Each pivot pin 46 may be locked in place by burgeoning or burring both ends. After all gripping members 44 have been pivotally mounted, garter spring 48 is passed through spring aperture 47, and the ends of garter spring 48 are secured together. It is noted that, when assembled, garter spring 48 is tensioned sufficiently to bias each gripping member 44 inwardly toward the body axis of hub 36 to engagement with knurled surface49 of inner annular portion 39.

After assembly, each hub assembly 35 is placed on shaft 25 in the facing arrangement illustrated, along with an annular sheet guiding member 55, this latter element being secured to shaft 25 for rotation therewith. Shaft'25 is next journaled into

bearings

26, 27. Each hub assembly 35 is then adjustedso that camming portions 52 of gripping members 44 are engageable with acarnmingrace 58 in one of a pair of I

camming blocks

60, 61 mounted on side plates 1 1, 12, respectively. After adjustment, each hub assembly is locked onto shaft 25 by tightening screw 31 onto flat 32.

As best shown in FIG. 4, for camming block 61, each camming race 58 has a lead in segment 63, a central segment of constant radius 64 and a lead out segment 3 65. In the preferred embodiment each

camming block

60,61, and hub assemblies 35 are so arranged that the finger portion 50 of each gripping member 44 is gradually retracted from sheet guiding surface 40 as the camming portion 52 rides along lead in segment 63. As camming portion 52 rides along central segment 64, finger portion 50 is maintained in a non-gripping position away from surface. 40. As camming portion 52 rides along lead out segment 65, finger portion 50 is gradually returned to a gripping position with surface 40 by garter spring 48.

As will now be evident, in an assemblieddevice, as

' provided for conveying sheet along this second direction to remote locations.

Annular sheet guiding member 55 is utilized in the preferred embodiment for preventing sheet 20 from wrinkling or buckling along angular path 0,. In some applications of the invention, sheet 20 may have such sufficient thickness or width that wrinkling or buckling is not a significant problem. In such applications,

. 39 is provided with a groove for snugly receiving O-ring shaft 25 and hub assembly 35 are rotated by gear 28,

successive finger portions are maintained in gripping relation with knurled surface 40 by garter spring 48 along angular path 0 are gradually retracted from surface 40 by camming race segment 63 along angular path 0,, are maintained in a retracted position by camming segment 64 along angular path 0 and are gradually returned to the .initial gripping relation by garter spring 48 along angular path 0,..Thus, when a properly sized sheet 20 is fed into the unit along entrance platform 18, the edges of sheet 20 are gradually gripped between successive finger portions 50 and surface 40 along path 0,. Along path 0, sheet 20 is progressively raised and rotated about the axis of shaft 25 by the clenching action'of finger portions 50 and surface 40. Along path 0, the edges of sheet 20 are gradually released and sheet 20 is progressively conveyed along exit platform 23 in a substantially reverse direction from entrance direction 21 by the positive propulsion afforded by theclenched finger portions 50 acting on the edges of the rearward portions of sheet 20. If desired, additional sheet conveying devices may be 40". If desired, O-ring 40, may also be cemented in place.

In some applications, it may be necessary to handle sheets of widely differing widths. In such applications, it is highly desirable to provide either one or both hub assemblies 35 and camming blocks 60, 61 with the adjustable feature shown in FIGS. 7 and 8 for the righthand portion of the unit. As seen in these figures, flat 32 is extended toward the center of shaft 25 to permit a greater axial adjustment of hub assembly 35 Body portion 37 of hub 36 is provided with an annular groove 69 sized to accommodate the upper central wall portion 70 of a movable support member 71 to which camming block 61 is attached. Support member 71 is provided with a pair of

lower rongues

72, 73 which are slidably received in similarly shaped tracks cut into a base plate 76 substantially parallel to shaft 25.

As will now be evident, as hub assembly 35 is adjusted along shaft 25, support member 71 follows the axial motion of hub assembly 35, thereby maintaining the relation between camming portion 52 of each gripping member 44 and race 58 of camming block 61. In this way, the working width of the sheet handling device may be easily varied to accommodate sheets of differing widths. If desired, other known locking arrangements than screw 31 and flat 32 may be provided for hub assembly 35.

Sheet handling devices constructed according to the above-described invention have been found to provide excellent results with flexible sheets of widely varying types and widths. Because of the relatively small number of working elements and the fact that each hub assembly is constructed from identical elements, such devices are inexpensive to manufacture and capable of prolonged use without mechanical failure.

While the foregoing provides a full disclosure of the preferred embodiments of the invention, it is understood that various modifications, alternate constructions, and equivalents may be employed without departing from the true spirit and scope of the invention. For example, gripping members 44 and camming blocks 60, 61 may be designed so that the biasing roles of garter spring 48 and race 58 are reversed. In addition, the shape of race 58 may be altered to provide angular paths 6, 0 of different sizes than that illustrated.

Therefore, the above description and illustrations should not be construed as limiting the scope of the invention which is solely defined by the appended claims.

What is claimed is:

l. A sheet handling device comprising:

. a frame;

' a rotatable shaft journaled in said frame;

a hub mounted on said shaft for rotation therewith, said hub having a substantially cylindrical sheet guiding surface;

a plurality of gripping members pivotally mounted on said hub about the axis of said shaft in different substantially radial pivotal planes, each gripping member having a finger portion with a surface engageable with said sheet guiding surface for gripping a sheet therebetween;

first means for biasing said gripping fingers toward said sheet guiding surface over a first predetermined angular path; and

second means for biasing said gripping fingers away from said sheet guiding surface over a second predetermined angular path,

said first means including a single spring disposed about said hub and coupled to each of said gripping members.

2. The apparatus of claim 1 wherein each of said gripping members is provided with an aperture inboard of the pivotal axis and said single spring is disposed within each of one said apertures.

3. The apparatus of claim 1 wherein said hub is provided with an axially adjustable means for mounting said hub on said shaft and further including means for adjustably mounting said second bias means along a path parallel to said shaft.

I 4. The apparatus of claim 1 wherein said second means comprises a stationary camming block having a camming race defining said second predetermined angular path and each of said gripping members is provided with a camming portion engageable with said camming race.

5. The apparatus of claim 4 wherein said camming race comprises the inner surface of said camming block.

6. The apparatus of claim 4 wherein saidhub is provided with an axially adjustable mounting means for mounting said hub on said shaft and further including means for adjustably mounting said camming block along a path parallel to said shaft.

7. The apparatus of claim 6 wherein said camming block mounting means includes a track for defining said path and a tongue member slidably disposed on said track.

8. The apparatus of claim 1 wherein said hub is provided with a'plurality of radially extending slotted boss members each having a pivot pin bore, and each of said gripping members is provided with a corresponding bore and positioned in a different one of said slotted boss members with said bores aligned, and further including a plurality of pivot pins each secured in a different one of said pivot pin bores.

9. The apparatus of claim 1 further including a substantially cylindrical sheet guiding member secured inboard of said hub on said shaft for rotation therewith.

10. The apparatus of claim 1 further including a curved sheet deflector mounting adjacent said sheet guiding surface.

l l. A sheet handling device comprising:

a frame;

a rotatable shaft journaled in said frame;

a pair of hubs mounted on said shaft, each said hub having a substantially cylindrical sheet guiding surface;

a plurality of gripping members each pivotally mounted on different ones of said hubs about the axis of said shaft in substantially radial pivotal planes, each gripping member having a finger portion with a surface engagable with one of said sheet guiding surfaces for gripping a sheet therebetween;

first means for biasing said gripping fingers toward said sheet guiding surfaces over a first predetermined angular path;

second means for biasing said gripping fingersaway from said sheet guiding surfaces over a second predetermined angular path; and

said first means comprising a pair of springs each disposed about a different one of said hubs and coupled to each of said gripping members mounted on said different one of said hubs.

12. The apparatus of claim 11 wherein each of said gripping members on each one of said hubs is provided with an aperture inboard of the pivotal axis and each said spring is disposed within one of said apertures in said gripping members mounted on the associated hub.

13'. The apparatus of claim 11 wherein at least one of said hubs is provided with an axially adjustable means i for mounting said hub on said shaft and further including means for adjustably mounting said second bias means along a path parallel to said shaft.

14. The apparatus of claim 11 wherein said second means comprises a pair of stationary camming blocks each mounted adjacent a different one of said hubs and each having a camming race defining said second predetermined angular path, and wherein each of said gripping members is provided with a camming portion engageable with said camming race of said adjacent camming block.

15. The apparatus of claim 14 wherein each of said camming races comprises the inner surface of the associated camming block.

16. The apparatus of claim 14 wherein at least one of said hubs is provided with an axially adjustable mounting means for mounting said hub on said shaft, and further including means for adjustably mounting said adjacent camming block along a path substantially parallel to said shaft. 7

17. The apparatus of claim 16 wherein said camming block mounting means includes a track for defining said path and a tongue member slidably disposed on said track.

18. The apparatus of claim 11 wherein each of said hubs is provided with a plurality of radially extending slotted boss members each having a pivot pin bore, and each of said gripping members is provided with a corresponding bore and positioned in a different one of saidslotted boss members with said bores aligned, and further including a plurality of pivot pins each secured in a different one of said Pivot pin bores. I

19. The apparatus of claim 11 further including a substantially cylindrical sheet guiding member secured between said hubs on said shaft for rotation therewith.

Claims

1. A sheet handling device comprising: a frame; a rotatable shaft journaled in said frame; a hub mounted on said shaft for rotation therewith, said hub having a substantially cylindrical sheet guiding surface; a plurality of gripping members pivotally mounted on said hub about the axis of said shaft in different substantially radial pivotal planes, each gripping member having a finger portion with a surface engageable with said sheet guiding surface for gripping a sheet therebetween; first means for biasing said gripping fingers toward said sheet guiding surface over a first predetermined angular path; and second means for biasing said gripping fingers away from said sheet guiding surface over a second predetermined angular path, said first means including a single spring disposed about said hub and coupled to each of said gripping members.

4. The apparatus of claim 1 wherein said second means comprises a stationary camming block having a camming race defining said second predetermined angular path and each of said gripping members is provided with a camming portion engageable with said camming race.

6. The apparatus of claim 4 wherein said hub is provided with an axially adjustable mounting means for mounting said hub on said shaft and further including means for adjustably mounting said camming block along a path parallel to said shaft.

8. The apparatus of claim 1 wherein said hub is provided with a plurality of radially extending slotted boss members each having a pivot pin bore, and each of said gripping members is provided with a corresponding bore and positioned in a different one of said slotted boss members with said bores aligned, and further including a plurality of pivot pins each secured in a different one of said pivot pin bores.

11. A sheet handling device comprising: a frame; a rotatable shaft journaled in said frame; a pair of hubs mounted on said shaft, each said hub having a substantially cylindrical sheet guiding surface; a plurality of gripping members each pivotally mounted on different ones of said hubs about the axis of said shaft in substantially radial pivotal planes, each gripping member having a finger portion with a surface engagable with one of said sheet guiding surfaces for gripping a sheet therebetween; first means for biasing said gripping fingers toward said sheet guiding surfaces over a first predetermined angular path; second means for biasing said gripping fingers away from said sheet guiding surfaces over a second predetermined angular path; and said first means comprising a pair of springs each disposed about a different one of said hubs and coupled to each of said gripping members mounted on said different one of said hubs.

13. The apparatus of claim 11 wherein at least one of said hubs is provided with an axially adjustable means for mounting said hub on said shaft and further including means for adjustably mounting said second bias means along a path parallel to said shaft.

16. The apparatus of claim 14 wherein at least one of said hubs is provided with an axially adjustable mounting means for mounting said hub on said shaft, and further including means for adjustably mounting said adjacent camming block along a path substantially parallel to said shaft.

18. The apparatus of claim 11 wherein each of said hubs is provided with a plurality of radially extending slotted boss members each having a pivot pin bore, and each of said gripping members is provided with a corresponding bore and positioned in a different one of said slotted boss members with said bores aligned, and further including a plurality of pivot pins each secured in a different one of said pivot pin bores.