US3606308A

US3606308A - Sheet gripping device

Info

Publication number: US3606308A
Application number: US835062A
Authority: US
Inventors: Harry E Mowry; Louis A Ricardo; Guy V Carricato
Original assignee: MILLER PRINTING MACHINERY Co
Current assignee: MILLER PRINTING EQUIPMENT Corp A CORP OF DE
Priority date: 1969-06-20
Filing date: 1969-06-20
Publication date: 1971-09-20
Anticipated expiration: 1988-09-20
Also published as: DE2030040B2; DE2030040A1; JPS5011291B1; GB1314856A; FR2046964A1; GB1314857A; CH524460A; FR2046964B1; DE2030040C3; SE373312B

Abstract

A SHEET GRIPPING DEVICE INCLUDES A GRIPPER ASSEMBLY NONROTATABLY MOUNTED ON A GRIPPER SHAFT. AN LINE MEMBER ROTATABLY SUPPORTS THE GRIPPER SHAFT ADJACENT ONE END AND IS NONROTATABLY SECURED TO AN INTERMEDIATE SHAFT ADJACENT THE OTHER END. A FIRST CAM FOLLOWER LEVER IS CONNECTED TO THE INTERMEDIATE SHAFT AND IS ARRANGED TO OSCILLATE THE END OF THE LINK MEMBER SUPPORTING THE GRIPPER SHAFT. A SECOND CAM FOLLOWER LEVER IS NONROTATABLY CONNECTED TO THE GRIPPER SHAFT AND HAS A CAM ROLLER URGED INTO ABUTTING RELATION WITH A CAM SURFACE FIXED ON TEH CYLINDER. MOVEMENT OF THE LINK MEMBER BY THE FIRST CAM FOLLOWER MOVES THE GRIPPER ALONG A PATH SIMILAR TO THE CAM SURFACE AGAINST WHICH THE CAM ROLLER ON THE SECOND CAM FOLLOWER IS URGED. THE CONFIGURATION OF THE CAM MEMBERS DETERMINES THE PATH FOLLOWED BY THE GRIPPER ASSEMBLY. THE GRIPPER ASSEMBLY INCLUDES A LEVER NONROTATABLY SECURED AT ONE END TO THE GRIPPER SHAFT WITH A BRACKET EXTENDING LATERALLY THEREFROM. THE GRIPPER MEMBER HAS A LATERALLY EXTENDING GRIPPER FINGER THAT ABUTS A GRIPPER PAD ON THE CYLINDER WITH AN END PORTION EXTENDING LATERALLY THEREFROM. THE GRIPPER MEMBER ALSO HAS AN INTERMEDIATE PORTION WITH AN ADJUSTING SCREW MOVABLE LONGITUDINALLY RELATIVE TO THE GRIPPER MEMBER. THE GRIPPER MEMBER IS SLIDABLY POSITIONED ON THE LEVER AND A SPRING BETWEEN THE BRACKET AND GRIPPER MEMBER END PORTION URGES THE GRIPPER FINGER AGAINST THE GRIPPER PAD. UPON UPWARD MOVEMENT OF THE LEVER, THE BRACKET THEREON CONTACTS THE ADJUSTING SCREW ON THE GRIPPER MEMBER AND LIFTS THE GRIPPER FINGER FROM THE GRIPPER PAD.

Description

Z-llln In...

2 Sheets-Shoot l H. E. MOWRY ETAL SHEET GRIPPING DEVICE Sept. 20, 1971 Filed June 20, 1969 Mair Attorney m vnvrons HARRY 5. Jimmy,

60) ll. CARR/CATO and LOU/S A. R/LARDO 5 44. J

Sept. 20, 1971 H. E. MOWRY E-TAL 3,606,308

swam? GRIPPING DEVICE Filed June 20, 1969 2 Sheets-Sheet 2 d S n W M a .r T Y T 0 l N m WCA o e .r u m N RR 0 4 .7 CA/ W H 6 w M E 5 PE 7 w United States Patent 3,606,308 SHEET GRIPPING DEVICE Harry E. Mowry, Louis A. Ricardo, and Guy V. Carricato, Pittsburgh, Pa., assignors to Miller Printing Machinery Co., Pittsburgh, Pa.

Filed June 20, 1969, Ser. No. 835,062 Int. Cl. B65h 5/14 US. Cl. 271-53 14 Claims ABSTRACT OF THE DISCLOSURE A sheet gripping device includes a gripper assembly nonrotatably mounted on a gripper shaft. Au link member rotatably supports the gripper shaft adjacent one end and is nonrotatably secured to an intermediate shaft adjacent the other end. A first cam follower lever is connected to the intermediate shaft and is arranged to oscillate the end of the link member supporting the gripper shaft. A second cam follower lever is nonrotatably connected to the gripper shaft and has a cam roller urged into abutting relation with a cam surface fixed on the cylinder. Movement of the link member by the first cam follower moves the gripper along a path similar to the cam surface against which the cam roller on the second cam follower is urged. The configuration of the cam members determines the path followed by the gripper assembly. The gripper assembly includes a lever nonrotatably secured at one end to the gripper shaft with a bracket extending laterally therefrom. The gripper member has a laterally extending gripper finger that abuts a gripper pad on the cylinder with an end portion extending laterally therefrom. The gripper member also has an intermediate portion with an adjusting screw movable longitudinally relative to the gripper member. The gripper member is slidably positioned on the lever and a spring between the bracket and gripper member end portion urges the gripper finger against the gripper pad. Upon upward movement of the lever, the bracket thereon contacts the adjusting screw on the gripper member and lifts the gripper finger from the gripper pad.

BACKGROUND OF THE INVENTION (1) Field of the invention This invention relates to a sheet gripping device and more particularly to a sheet gripping device where, on opening and closing, the gripper finger follows a path controlled by the cam surfaces.

(2) Description of the prior art The conventional sheet gripping devices include gripper fingers that are nonrotatably secured to a gripper shaft. The gripper fingers are moved toward and away from the gripper pad by rotating the gripper shaft. The gripper fingers follow a circular path because of their direct connection to a rotatable gripper shaft that is fixed within the cylinder. United States Pats. 703,605; 1,275,002; 2,599,776; 2,775,197 and 3,151,552 disclose gripper devices that follow a circular path.

With known gripper devices, a wide longitudinal cylinder gap is required to accommodate the grippers. The large gap is a limiting factor in reducing cylinder di- "ice ameters and press size. The problem of the large gap is discussed in United States Patent 3,151,552 and a proposed solution therein is to encircle the hub clamping screw with the gripper spring to provide a concentric relation therebetween and thus reduce the lateral dimension of the gripper assembly and in turn, reduce the size of the cylinder gap.

SUMMARY OF THE INVENTION Briefly, the invention is directed to a gripper device that moves perpendicular to the gripper pad upon closing and eliminates sheet movement upon engagement of the sheet between the grpper finger and pad. The gripper device permits a narrow cylinder gap so that the diameter of the cylinder and the press size can be reduced substantially.

The sheet gripper device includes a gripper assembly and means to open and close the gripper device. The gripper assembly includes a lever having a bracket member extending laterally therefrom. The lever is nonrotatably secured at one end to a gripper shaft. A gripper member is slidably positioned on the lever and movable longitudinally relative thereto. The gripper member has a laterally extending gripper finger end portion that is positioned in overlying relation with the fixed gripper pad and a laterally extending other end portion that is positioned below the lower bracket member. A spring is positioned between the bracket member and the gripper member end portion to urge the gripper finger into abutting relation with the gripper pad. The actuating means for opening and closing the gripper assembly includes a cam member having a cam surface fixedly positioned relative to the gripper pad. A cam follower abuts the cam surface and the cam follower is nonrotatably mounted on the gripper shaft. Means are provided to move the gripper shaft relative to the cylinder axis to thereby move the cam follower on the cam surface and also move the gripper finger along a path substantially parallel tothe cam surface. The cam surface preferably has a configuration to move the gripper finger perpendicular to the outer surface of the gripper pad as the gripper finger closes against the gripper pad. With this arrangement, the gripper finger is moving perpendicular to the edge of the sheet as it is engaging the sheet between the gripper finger and gripper pad. This provides a final closing motion on the sheet that is perpendicular to the gripper pad and does not move the sheet of varying thickness along the cylinder upon closing and thereby, maintains registry. The cam configuration for moving the gripper member permits the longitudinal gap in the cylinder especially adjacent the external surface of the cylinder to be maintained as a relatively narrow gap so that it is possible to reduce both the cylinder diameter and the overall press size.

Accordingly, the principal object of this invention is to provide a sheet gripping device that requires a relatively narrow gap or opening in the cylinder periphery.

Another object of this invention is to provide a sheet gripping device wherein the gripper finger moves perpendicular to the sheet and gripper pad upon closing so that the gripper does not impart motion to the sheet on the cylinder during engagement of the sheet by the gripper.

These and other objects and advantages of this invention will be more completely disclosed and described in the following specification, the accompanying drawings and the appended claims.

3 BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a fragmentary plan view of a cylinder with the improved sheet gripping device positioned therein.

FIG. 2 is a view in end elevation illustrating the gripper assembly in closed position.

FIG. 3 is a view similar to FIG. 2 illustrating the initial movement of the cam follower roller along the cam surface to open the gripper assembly. The movement of the gripper finger in FIG. 3 is similar in both opening and closing of the gripper assembly.

FIG. 4 is a view similar to FIG. 3 illustrating the gripper assembly in an open position.

FIG. 5 is a fragmentary view of the gripper assembly.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, there is illustrated a printing press cylinder generally designated by the numeral that has a longitudinal recessed portion 12 with an enlarged base portion 14 and a narrow longitudinal gap or opening 16 at the surface 18 of cylinder 10'. The cylinder 10 has a gripper pad 20 secured to the cylinder 10 adjacent an edge of the gap 16 with an upper surface 22 that is substantially parallel to the cylinder surface 18.

The cylinder 10 is rotatably supported on an axial shaft 24 in press frame member (not shown). Suitable driving means are provided to rotate the cylinder 10'. A cam member 26 is fixedly positioned relative to the cylinder 10 and has a cam surface 28. The cam '26, with the cam surface 28 opens and closes the grippers in timed relation at preselected angular positions of the cylinder 10.

The cylinder longitudinal recessed portion .12 has a plurality of bearings 30 secured therein by means of screws 32. The bearings 30 have an upwardly extending portion 34 with a bore 36 therein. An intermediate shaft 38 is rotatably supported in the bearings 30 and is positioned parallel to the axis of the cylinder 10. The bearings 30 maintain the intermediate shaft 38 in fixed axial relation with the axis of cylinder 10. A link member 40 is nonrotatably journaled at one end on the shaft 3-8 by a key 41 (FIG. 1) and extends laterally therefrom. A gripper shaft 42 is rotatably journaled in the other end of link member 40 and is pivotally movable about the axis of the intermediate shaft 38 by link member 40. A cam follower 44 is nonrotatably journaled at one end of intermediate shaft 38 by a key 45 and has a cam roller 46 rotatably positioned on the other end. The cam roller 46 is urged into abutting relation with the cam surface 28 of cam member 26 by a spring member 48. It should be understood, the arrangement of the spring member 48- to urge the cam roller 46 against the cam surface 28 is illustrative only and other means for urging the cam roller 46 against the cam surface 28 may be employed. Thus, upon rotation of the cylinder 10 relative to the fixed cam 26, the cam follower 44 rotates with the cylinder 10 and the cam roller rides on the fixed cam surface 28. The configuration of the cam surface 28 is such that the cam follower 44 pivots the link 40 about the intermediate shaft 38 at preselected angular positions of the cylinder 10 to thereby open and close the grippers at preselected angular positions of the cylinder 10'.

The end portion of cylinder 10' has a cam bracket 50 secured thereto by means of bolts 52.. The cam bracket 50 extends across the gap 16 and has a cam surface generally designated by the numeral 54 that extends angularly to the cylinder periphery 18. The cam surface 54 has a first portion 56 and a second portion 57. The particular configuration of the cam surface '54 will be discussed in detail hereafter.

A cam follower 58 is nonrotatably journaled on the gripper shaft 42 by a key 59 and has a cam roller 60 that is arranged to ride on the cam surface 54. The cam roller 60 is urged against the cam surface 54- by means of the spring 62 that is secured by a pin 64 to the end portion of cylinder 10. Again, the spring 62 as a means for urging the cam roller 60 against the cam surface 54 is for illustrative purposes only and other suitable means may be employed.

With the above arrangement, the oscillation of the cam follower 44 by the cam surface 28, upon rotation of cylinder 1.0 Will oscillate or rotate the link 40 about the axis of intermediate shaft 38- to thereby axially displace the gripper shaft 42 relative to the axis of the cylinder 10. The axial displacement of the gripper shaft 42 will move the cam roller 60 along the cam surface 54 so that the cam follower 58 will impart rotation to the gripper shaft 42 when the cam follower roller is displaced angularly thereto by means of the cam surface 57 as will be later explained. The link 40 is, therefore, arranged to rotate gripper shaft 42 about the axis of intermediate shaft 3 8 and the cam surface '54 is arranged to rotate the cam follower 58 about the axis of the gripper shaft 42.

Although a single gripper actuating mechanism has been described, it should be understood that a plurality of link members 40 and bearing members 30 may be positioned within the recess 12 to suitably support the intermediate shaft 38 and gripper shaft 42 as is illustratively shown in FIG. 1. There also may be provided a second cam bracket 50 on the opposite side of the cylinder 10 with a similar cam surface 54 and a cam follower 58 nonrotatably connected to the opposite end of the gripper shaft 42.

A plurality of gripper assemblies generally designated by the numeral 70 and illustrated in detail in FIG. 5 are nonrotatably secured to the gripper shaft 42 by means of keys 72. The gripper assemblies 70 include a ways lever 74 that has an end portion. nonrotatably secured to the gripper shaft 42 and a gib bracket 76 secured to a side portion thereof. A gripper member 78 has a laterally extending gripper finger 80 with a surface 82 that is arranged to abut the surface 22 of the gripper pad 20. The gripper pad 20, although secured to the cylinder 10, will for convenience be referred to as a portion of the gripper assembly. The gripper member 78 has a laterally extending other end portion 84 with a longitudinal bore 86 therein and a spaced parallel laterally extending portion 88 with a longitudinal threaded bore 90 therein. An adjusting screw 92 is threadedly positioned in the threaded bore 90. The gripper member 78 is slidably positioned in the ways lever 74 and is arranged to move longitudinally relative thereto. A shaft member 94 is secured to the bracket 76 and extends into the bore 86 of the gripper member laterally extending end portion 84. A spring 96 urges the gripper member end portion 84 away from the bracket member 76 and urges the gripper finger 80 into abutting relation with the gripper pad 20. The adjusting screw 92 is arranged to provide the clearance between the top of the bracket 76 and the gripper member laterally extending portion] 88. With this previously described arrangement of the gripper assemblies 70, the vertical axial displacement of the gripper shaft 42 toward the gripper pad 20 will first slidably move the gripper member 78 relative to the lever 74 until the bottom portion of adjusting screw 92 abuts the upper surface of the bracket 76. Further vertical displacement of the gripper shaft 42 will then move the gripper member 78 and will move the gripper finger surface 82 away from the surface 22 of gripper pad 20. The arcuate displacement of the gripper shaft 42 relative to the intermediate shaft 38 will first move the ways lever 74 relative to the gripper member 78 until the adjusting screw 92 abuts the surface of bracket 76. Further arcuate vertical displacement of the gripper shaft 42 will move the gripper finger 80 away from the gripper pad 20. The cam surface 54 guides and controls the relative movement of the cam finger surface 82 relative to the surface 22 of gripper pad 20.

OPERATION The sheet gripping device previously described operates in the following manner. As illustrated in FIG. 2, the

gripper finger surface '82 is urged against the surface 22 of the gripper pad 20 and engages an edge of sheet S therebetween. This is the closed position of the gripper assembly 70. Rotation of the cylinder relative to the fixed cam 26 moves the cam roller 46 of cam follower 44 along the cam surface 28. The cam surface 28 has such a profile that a recessed portion pivots the cam follower 44 about shaft 38 in a counter-clockwise relation because the cam roller 46 is continually urged against the cam surface 28 by the spring 48. This part of the profile of the cam 26 functions to open the gripper assembly 70.

The rotation of the cam follower 44 in a counterclockwise direction transmits the rotation to intermediate shaft 38 which, in turn, rotates the link member 40 in the same counter-clockwise direction. The link member 40 is rotatably secured to the gripper shaft 42 and moves the gripper shaft axially in the same counter-clockwise direction as the link 40 but because of the rotatable connection between gripper shaft 42 and the link 40, the link permits the gripper shaft 42 to rotate about its own axis as it pivots about shaft 38. Thus, the link member 40 functions to displace the gripper shaft 42 axially relative to the axis of cylinder 10.

The cam follower 58 is nonrotatably secured to the gripper shaft 42 and is also axially displaced with the gripper shaft 42 upon counter-clockwise movement of the link member 40. Initial axial displacement of the link 40 moves the gripper shaft 42 upwardly and in turn moves the ways lever 74 relative to the gripper member 78 until the adjusting screw 92 abuts the upper portion. of bracket member '60.

Both the cam follower 58 and the gripper assemblies 70 are nonrotatably secured to the gripper shaft 42 by means of the

key members

59 and 72 respectively. The cam roller 60 of cam follower 58 is constrained to move according to the profile of the cam surface 57 to thus limit the axial rotation of the gripper shaft 42 so that the first movement of the gripper finger 80 is substantially perpendicular to the surface 18 of cylinder 10. The initial movement of the cam follower 58 and the gripper finger 80 is illustrated in FIG. v3 where the gripper finger surface 82 is substantially parallel to the surface 22 of gripper pad 20. Thus, the initial opening movement of the gripper finger 80 is in a direction perpendicular to the surface of pad 20.

Further rotation of the link 40 by cam follower 44 displaces the gripper shaft to the position illustrated in FIG. 4. The cam roller 60 of cam follower 58 has moved up onto another part of the profile of the cam surface 57. The movement of cam roller 60 along cam surface 57 rotates the cam follower 58 and the gripper shaft 42 nonrotatably secured thereto to the position illustrated in FIG. 4. Thus the cam followed 58 rotates both the gripper shaft 42 and the gripper assembly 70 nonrotatably secured thereto until the gripper finger 80 is moved to the completely open position such as illustrated in FIG. 4.

In closing the gripper finger 80 on the pad 20, the cam follower 46 is urged upwardly by a portion of the cam surface 28 to pivot the cam follower 44 in a clockwise direction. The link member '40 also pivots with the intermediate shaft 38 in a clockwise direction to axially displace the gripper shaft 42 toward the axis of cylinder 10.

The downward clockwise axial displacement of gripper shaft 42 moves the cam roller 60 of cam follower 58 along the portion 57 of the cam surface 54 to move the gripper finger 80 toward the gripper pad 20. When the link member 40 has rotated to the position illustrated in FIG. 3, the cam surface '56 of cam '54 has moved the cam follower into a position substantially perpendicular to the surface of the cylinder thereabove. Thus, the under surface 82 of gripper finger 80 is positioned directly above the surface 22 of pad and is spaced therefrom with an edge of sheet S therebetween. The gripper finger surface 82 has not as yet engaged the edge of sheet S to the surface 22 of the pad 20. Further rotation of link by the cam member 26 moves the gripper shaft 42 downwardly toward the axis of cylinder 10. The cam follower '58 that controls the direction of movement of gripper finger has the cam roller 60 positioned on the vertical portion 56 of cam 54 so that upon downward movement of the gripper shaft 42, the gripper finger 80 is moved downwardly in a direction perpendicular to the surface of cylinder surface 18 to engage the edge of sheet S between the

surfaces

82 and 22. Further movement of the gripper shaft 42 moves the ways lever 74 relative to the gripper member 78 to exert a compressive force on spring 94 and forcibly engage the sheet S between the gripper finger 80 and pad 20.

It should be noted the last closing movement of the gripper finger 80 against the gripper pad 20 is in a direction perpendicular to the surface of gripper pad 20 so that there is no relative circumferential movement or displacement of the sheet on the cylinder surface 18 by the final closing movement of the gripper 80 as is present 'where the gripper finger 80 follows a circular path about the axis of the gripper shaft.

It should be noted that the path followed by the gripper finger 80 is defined by the profile of the cam surface 54. With this arrangement it is possible to have the cam finger 80 follow substantially any preselected path as defined by the cam surface 54. One of the advantageous features of the above described gripper device is the perpendicular movement of the gripper finger surface 82 relative to the pad 20 through a substantial distance upon closing. The gripper device is thus versatile in that it can be utilized with papers of different thickness without the gripper finger 80 displacing the sheet along the surface of the cylinder 80'. Another advantageous. feature of the sheet gripper device is the relatively narrow gap required for the gripper assemblies. The gap 16 illustrated in the drawings, is controlled by the desired movement of the gripper finger 82. As illustrated in FIG. 4, the gripper 78 is in a fully opened position. If it were desired to reduce the gap 16 further, the cam surface 54 could be modified to move the gripper finger 80 in a less arcuate path upon completely opening. With this arrangement it is possible to have the gripper finger 82 move to a completely open position and remain substantially perpendicular to the surface 18 of the cylinder and thus reduce the gap 16 to a width slightly larger than the gripper member 78 adjacent the finger 80.

According to the provisions of the patent statutes, the principle, preferred construction, and mode of operation of the invention have been explained, and what is considered to represent its best embodiment has been illustrated and described.

We claim:

1. A gripper assembly comprising,

a gripper shaft,

a lever nonrotatably secured at one end to said gripper shaft and having a bracket member extending laterally therefrom,

a gripper member slidably positioned on said lever and movable longitudinally thereto,

said gripper member having a laterally extending gripper finger end portion positioned in overlying relation with a fixed gripper pad,

said gripper member having a laterally extending other end portion positioned below said lever bracket member, and

resilient means urging said bracket member and said gripper member other end portion away from each other to thereby urge said gripper finger end portion into abutting relation with said gripper pad.

2. A gripper assembly as set forth in claim 1 in which,

said gripper member includes a laterally extending member positioned above said lever bracket member, and

said laterally extending member operable to be engaged by said bracket member upon vertical movement of said lever relative to said gripper member to thereby move said gripper finger end portion away from said gripper pad.

3. A gripper assembly as set forth in claim 2 in which,

said laterally extending member is spaced from said bracket member when said gripper finger engages said gripper pad so that said lever moves a preselected distance vertically before said bracket member engages said laterally extending member.

4. A gripper assembly as set forth in claim 3 in which,

said laterally extending member is adjustable longitudinally on said gripper member to thereby adjust the space between said laterally extending member and said bracket member and thereby vary the distance travelled by said lever before said gripper finger moves away from said gripper pad.

5. A sheet gripping device comprising,

a gripper assembly having a gripper finger abutting a gripper pad,

a gripper shaft with said gripper finger nonrotatably secured thereto,

a cam member having a cam surface rigidly positioned relative to said gripper pad,

a cam follower abutting said cam surface, said cam follower nonrotatably mounted on said gripper shaft, and

means to move said gripper shaft toward said gripper pad to thereby move said cam follower on said cam surface and thereby move said gripper finger away from said gripper pad along a path defined by said cam surface.

6. A sheet gripping device as set forth in claim 5 which includes,

means continuously urging said cam follower against said cam surface.

7. A sheet gripping device as set forth in claim 5 in which said means to move said gripper shaft includes,

a link member rotatably secured at one end to said gripper shaft and nonrotatably secured at the other end to an intermediate shaft, and

means to rotate said intermediate shaft and thereby move said gripper shaft.

8. A sheet gripping device as set forth in claim 7 in which said means to move said intermediate shaft includes,

a second cam follower nonrotatably secured at one end to said intermediate shaft and abutting a movable second cam surface at the other end, said second cam follower operable to move said gripper shaft in response to said second cam surface.

9. A sheet gripping device as set forth in claim 5 in which said gripper assembly includes,

a lever nonrotatably secured at one end to said gripper shaft and having a bracket member extending latterally therefrom,

10. A sheet gripping device as set forth in claim 5 which includes,

a cylinder having a longitudinal recessed portion with an enlarged base portion and a relatively narrow longitudinal opening at the peripheral surface of said cylinder,

said gripper pad mounted on said cylinder periphery adjacent an edge of said narrow longitudinal opening, and

a cam bracket secured to said cylinder with said cam member mounted thereon.

11. A sheet gripping device as set forth in claim 10 which includes,

a plurality of bearings mounted in said cylinder recessed portion,

an intermediate shaft rotatably mounted in said bearings and extending longitudinally in said recessed portion,

said gripper shaft positioned in said recessed portion substantially parallel to said intermediate shaft, and

a link member rotatably secured at one end to said gripper shaft and nonrotatably secured at the other end to said intermediate shaft.

12. A sheet gripping device as set forth in claim 10 which includes,

resilient means connected to said cylinder and to said cam follower,

said resilient means operable to urge said cam follower against said cam surface.

13. A sheet gripping device as set forth in claim 11 in which,

a second cam member is mounted adjacent said cylinder so that said cylinder rotates relative to said second cam member,

a second cam follower having an end portion nonrotatably secured to said intermediate shaft and an end portion abutting the cam surface of said second cam member, and

resilient means urging said second cam follower against said cam surface.

14. A sheet gripping device as set forth in claim 5 in i which,

9/1922 Evans et a1. 271-53 4/1928 Nayer 101409 10/1964 Peyrebrune 10l-409 FOREIGN PATENTS 1,212,562 9/1966 Germany 27l-53 JOSEPH WEGB'REIT, Primary Examiner B. H. STONER, JR., Assistant Examiner