US3865362A

US3865362A - Sheet transfer cylinder

Info

Publication number: US3865362A
Application number: US335072A
Authority: US
Inventors: Dennis J Luffy; Robert L Mosemiller
Original assignee: MILLER PRINTING MACHINERY Co
Current assignee: MILLER PRINTING EQUIPMENT Corp A CORP OF DE
Priority date: 1973-02-23
Filing date: 1973-02-23
Publication date: 1975-02-11
Anticipated expiration: 1992-02-11

Abstract

A cylinder shaft is rotatably journaled in a frame and has a front edge gripper shaft supported thereon in spaced parallel relation thereto. A plurality of gripper fingers are nonrotatably mounted on the front edge gripper shaft and are urged by springs into abutting relation with underlying gripper pads. A lever arm connected to an end of the front edge gripper shaft has a cam follower positioned in an endless cam track secured to the frame, so that upon rotation of the cylinder shaft the front edge gripper shaft oscillates to open and close the front edge grippers. A tail edge gripper shaft is supported in parallel spaced relation to the cylinder shaft and has elongated tail edge grippers secured thereto. The tail edge gripper shaft is arranged to revolve at a preselected angular velocity about its axis as the cylinder shaft rotates through gearing and a cam follower positioned in an endless cam that rotates at the same angular velocity as the cylinder shaft. The tail edge grippers are opened and closed by a cam follower abutting a cam member rotatably mounted on the tail edge gripper shaft. A lever connects the cam member to an actuator shaft that is oscillated upon rotation of the cylinder shaft by a cam follower abutting the cam surface of a fixed endless cam to thus open and close the tail edge grippers. Adjustment apparatus is provided to move the front edge and tail edge grippers toward and away from each other to accommodate different size sheets. The rotation of the tail edge gripper shaft permits the tail edge gripper to extend beyond the periphery of the transfer cylinder during a preselected portion of each revolution of the transfer cylinder and the tail edge gripper actuator is arranged to release the sheet when the tail edge gripper is extended.

Description

United States Patent 1191 1 Luffy et al.

[ SHEET TRANSFER CYLINDER [75] Inventors: Dennis J. Luffy, Butler; Robert L.

Mosemiller, Pittsburgh, both of Pa.

[73] Assignee: Miller Printing Machinery Co.,

Pittsburgh, Pa.

[22] Filed: Feb. 23, 1973 [2]] Appl, No.: 335,072

[52] U.S. Cl. ..27l/82, 101/410 [51] Int. Cl B65h 29/06 [58] Field of Search 271/82, 53, 79, 277, 241; 10l/409, 410

[56] References Cited UNITED STATES PATENTS 1,815,895 7/1931 Bennison l0l/4l0 1,916,454 7/1933 Wohlrabe 101/409 X 2,757,610 8/1956 Gegenheimer et al 271/79 X 3,703,282 11/1972 Henkel 271/79 3,703,863 1 1/1972 Giuiuzza l0l/410 X Primary E.raminerEvon C. Blunk Assistant Examiner.lames W. Miller Attorney, Agent, or Firm-Stanley J. Price, Jr.

[5 7] ABSTRACT A cylinder shaft is rotatably journaled in a frame and has a front edge gripper shaft supported thereon in spaced parallel relation thereto. A plurality of gripper fingers are nonrotatably mounted on the front edge Feb. 11, 1975 gripper shaft and are urged by springs into abutting relation with underlying gripper pads, A lever arm connected to an end of the front edge gripper shaft has a cam follower positioned in an endless cam track secured to the frame, so that upon rotation of the cylinder shaft the front edge gripper shaft oscillates to open and close the front edge grippers. A tail edge gripper shaft is supported in parallel spaced relation to the cylinder shaft and has elongated tail edge grippers secured thereto. The tail edge gripper shaft is arranged to revolve at a preselected angular velocity about its axis as the cylinder shaft rotates through gearing and a cam follower positioned in an endless cam that rotates at the same angular velocity as the cylinder shaft. The tail edge grippers are opened and closed by a cam follower abutting a cam member rotatably mounted on the tail edge gripper shaft. A lever connects the cam member to an actuator shaft that is oscillated upon rotation of the cylinder shaft by a cam tion of the transfer cylinder and the tail edge gripper I actuator is arranged to release the sheet when the tail edge gripper is extended.

7 Claims, 19 Drawing Figures PATENTH] FEB] 1 I975 sum l-UF s PATENIEUFEBI 1W5 3.865.362

SHEET nor 8 PATENTE FEB 1 1 I975 I 3. 865,362

SHEET 5 0F 8 SHEET TRANSFER CYLINDER BACKGROUND OF THE INVENTION l. Field of the Invention This invention relates to a sheet transfer cylinder that engages both the leading edge and the trailing edge of the sheet and more particularly a transfer cylinder in which the tail edge engaging device periodically extends beyond the periphery of the transfer cylinder.

2. Description of the Prior Art ln sheet delivery apparatus especially in large sheet fed presses and particularly perfecting presses the speed at which the press can operate and provide a high quality printed product is limited by the sheet delivery apparatus and especially the manner in which the freshly printed sheets are deposited on the pile. As the press speed is increased the sheets tend to flutter as they are delivered to the pile. This disturbance frequently causes streaks in the freshly printed product.

Several solutions of this sheet slowdown problem are suggested by the prior art. In U.S. Pat. No. 3,378,256 suction devices are provided to engage the tail end of the sheet while moving at sheet speed and then the suction devices decelerate to slow down the sheet and release the sheet, so that it may be deposited on a pile. Parallel linkages are employed to maintain the suction devices in a substantially horizontal plane duringthe slowdown operation. The sucker devices must first accelerate to sheet speed before the tail edge of the sheet is engaged by the sucker devices and the sucker devices must remain in engagement with the tail edge of the sheet during the sheet slowdown operation.

In U.S. Pat. No. 2,093,228 mechanical gripper devices are utilized to engage the tail edge of the sheet and slowdown the forward movement of the sheet. The mechanical gripper devices are mounted on parallel linkages that move at sheet speed as the tail edge of the sheet is engaged by the mechanical grippers. The mechanical grippers then move in a downward direction to lower the sheet onto the pile where the mechanical grippers release the sheet.

v The use of linkages to oscillate the sheet engaging devices and position the devices in a sheet receiving position, then accelerate the sheet engaging devices to sheet speed and thereafter reduce the acceleration of v the sheet engaging devices, limits the speed at which the sheets can be delivered to the pile. There is a need for sheet delivery apparatus that preferably revolves about an axis so that the rotational speed of the sheet gripping devices can be increased to match the desired high speeds of the sheet fed printing presses.

SUMMARY OF THE INVENTION This invention relates to a sheet transfer cylinder that has a cylinder shaft rotatably journaled in a press frame. A sheet front edge gripper shaft is positioned in parallel spaced relation to the cylinder shaft and is supedge gripper shaft is positioned in spaced parallel relation to the cylinder shaft and to the front edge gripper shaft. The tail edge gripper shaft is supported on the cylindershaft for rotation therewith. Sheet supporting means are provided with a cylindrical sheetsupporting surface. Tail edge gripper devices are secured to the tail edge gripper shaft and are arranged to engage the tailv edge of a sheet positioned on the sheet supporting surface. Means are provided to open and close the tail edge gripper device at preselected radial angular positions of the cylinder shaft. Other means are provided to extend the tail edge gripper device radially outwardly relative to the cylinder shaft beyond the periphery of the sheet supporting surface at preselected angular positions of the cylinder shaft.

With this arrangement the transfer cylinder rotating at high speed engages the front edge of a sheet and positions the sheet on the support surface of the cylinder as the cylinder rotates. The tail of the sheet is engaged by the tail edge grippers and the tail edge of the sheet remains engaged by the tail edge grippers as the front edge of the sheet is transferred to horizontally disposed gripper devices that are arranged to travel in an endless path toward the pile. Further rotation of the transfer cylinder moves the tail edge gripper devices outwardly beyond the periphery of the cylinder to a position adjacent the pile where the tail edge gripper devices are disengaged from the tail of the sheet so that the sheet may be deposited on the pile. The movement of the gripper device beyond the periphery of the transfer cylinder reduces the forward speed of the sheet so that it can be deposited on the pile without sheet flutter and damage to the .freshly printed sheet.

Accordingly, the principal object of this invention is to provide a rotatable device for engaging both the leading edge and trailing edge of a sheet.

Another object of this invention is to provide a rotatable sheet slowdown device that engages the tail edge of a sheet and reduces the speed of the sheet so that it can be deposited on a pile.

A further object of this invention is to provide a rotatable transfer cylinder that engages both the front edge and tail edge of a sheet and controls the release of the tail edge of the sheet to slow down the forward movement of the sheet.

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

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of the delivery apparatus and the relative position of the delivery apparatus to the impression and blanket cylinders of the last printing unit.

FIG. 2 is a view in section of the transfer cylinder that engages the front edge and trailing edge of the sheet and transfers the front edge of the sheet to grippers on a delivery conveyor.

FIG. 3 is a view in section taken along the line III-Ill of FIG. 2, illustrating the manner in which the segments of the transfer cylinder can be rotated relative to each other to adjust the peripheral distance between the sheet front edge gripper and the sheet tail edge gripper. FIG. 4 is a view in section taken along the line lV-IV of FIG. 2, illustrating the relative position of the front edge gripper and tail edge gripper and in phantom lines an adjusted position of the tail edge gripper to reduce the peripheral distance between the respective grippers around the transfer cylinder.

FIG. 5 is a view in section taken along the line VV of FIG. 2, illustrating the apparatus to rotate the shaft having the tail edge grippers mounted thereon.

FIG. 6 is a view in section taken along the line VI-VI of FIG. 2, illustrating the endless cam track for the cam follower connected through a lever to a shaft that is arranged to open and close the front edge grippers.

FIG. 7 is a view in section taken along the line VII- VII of FIG. 5, illustrating another portion of the apparatus for adjusting the peripheral distance beteen the front edge and tail edge grippers.

FIG. 8 is a view in section taken along the line VIII- VIII of FIG. 5.

FIG. 9 is a schematic view, illustrating the path of the tail edge grippers during a single revolution of the transfer cylinder.

FIG. 9a is an exploded view of the elements of the tail edge gripper.

FIG. 9b is an enlarged view in elevation of tail edge cam, illustrating in phantom the position of the cam follower where the gripper closes on the sheet and opens to release the sheet.

FIG. 10 is a top plan view of the frame having the chains and gripper guides or tracks for delivering the sheet from the transfer cylinder to the pile.

FIG. 11 is a view in section taken along the line XIXI of FIG. 10, illustrating the manner in which the frame is adjustable longitudinally for different sizedsheets. I

FIG. 12 is a fragmentary view in side elevation, illustrating one of the gripper guide tracks and the relative position of the frame to the transfer cylinder.

FIG. 13 is a fragmentary view in section of a gripper positioned in the gripper guide.

FIG. 14 is a fragmentary top plan view, illustrating the manner in which the grippers are connected to the chain.

FIG. 15 is a fragmentary view in section taken along the line XVXV of FIG. 13, illustrating in detail the actuator for opening the individual grippers.

FIG. 16 is a schematic illustration of a gripper as the gripper enters the arcuate portion of the gripper guides before the gripper begins to slow down. FIG. 17 is a view similar to FIG. 16, illustrating the gripper in the slowed down position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, there is schematically illustrated a sheet delivery mechanism generally designated by the numeral 10 that is positioned adjacent to the delivery end ofa printing press having an impression cylinder 12 and a blanket cylinder 14. An endless chain 16 has a plurality of gripper bars 18 connected thereto annd is reeved about a drive sprocket 20 and an idler sprocket 22. The drive sprocket 20 is positioned adjacent to the impression cylinder 12 and the grippers on gripper bars 18 are arranged to engage the front edge of the sheet as the sheet is positioned on the impression cylinder and being printed on the outer surface by blanket cylinder 14.

The gripper bars 18 have a velocity substantially the same as the peripheral velocity of the impression cylinder 12 as the grippers on gripper bar 18 engage the front edge of the sheet and convey the sheet along the path indicated by the chain 16 and up to the sprocket 22. The sprocket 22 is mounted on a shaft that is, in turn, supported in a delivery frame 24 that has a transfer cylinder 26 rotatably mounted adjacent thereto. A plurality of delivery chains 34 are mounted above the transfer cylinder 26 and have chain sprockets 30 and 32 with the endless chains 34 reeved therearound. Adjacent to the chains 34 are a plurality of gripper tracks 28 with the grippers 36 mounted therein. Grippers 36 are connected to the delivery chains 34 by a push rod as later explained.

The grippers 36 in the gripper tracks 28 are arranged to engage the front edge of the sheet while the sheet is on the transfer cclinder 26 and convey the sheet forwardly and deposit the sheet on the pile 38. A slitter mechanism 40 is positioned adjacent thetransfer cylinder 26 and is arranged to slit the sheets longitudinally before the sheets are deposited on the pile 38. As illustrated in FIG. 1, the chains 34 and gripper tracks 28 are movable longitudinally relative to the transfer cylinder 26 to accommodate sheets of different length.

The sheet transported by the grippers on gripper bar 18 on the first chain 16 is arranged to be transferred to front edge grippers 42 of transfer cylinder 26, as schematically illustrated in FIG. 1 and illustrated in greater detail in FIGS. 3, 4 and 12. Further rotation of transfer cylinder 26 transfers the front edge of the sheet from the front edge grippers 42 on transfer cylinder 26 to the front edge grippers 36 in gripper tracks 28 associated with the second endless chains 34. The front edge of the sheet is then conveyed forwardly toward the pile 38 by the grippers 36 in gripper track, 28 and the front edge grippers 36 in gripper track 28 release the sheet as it is deposited on the pile. As the tail edge of the sheet approaches the point of tangency between the transfer cylinder 26 and the first chains 16, the tail edge of the sheet is engaged by the tail edge grippers 44. The tail edge grippers 44, as illustrated in FIG. 9, move outwardly beyond the periphery of the transfer cylinder 26 while engaged to the tail edge of the sheet to slow down the sheet and release the sheet as it is deposited on the pile.

With this arrangement the sheet is first engaged by the transverse gripper bar 18 while the sheet is on the impression cylinder of the last printing unit. The sheet is conveyed by the transverse gripper bars 18 to the transfer cylinder 26. The front edge of the sheet is transferred from the gripper bars 18 to the lead edge grippers 42 in transfer cylinder 26 and the lead edge grippers 42 in transfer cylinder 26 thereafter transfer the front edge of the sheet to the front edge gripers 36 mounted in the gripper track 28, and the sheet is thereafter conveyed to'the pile 38.

The tail edge of the sheet is engaged by the tail edge grippers 44 on transfer cylinder 26 and the tail edge of the sheet remains engaged by the tail edge grippers 44 until the sheet is in substantially overlying relation with the pile 38. The grippers 36 first release the sheet to deposit it on the pile and thereafter the tail edge of the sheet is released by the tail edge grippers 44 to permit the sheet to be deposited on the pile without disturbances or flutter.

The transfer cylinder generally designated by the numeral 26 is illlustrated in detail in FIGS. 2 9 and includes a cylinder shaft 48 rotatably journaled in side frames 50 and 52. The side of the delivery mechanism 10, including the side frame 50, will also be referred to as the operator's side of the press and the delivery mechanism and the opposite side having the side frame 52 will also be referred to as the drive side of the press.

Nonrotatably mounted on the shaft 48 are a plurality of spaced cylindrical segments 54 illustrated in FIGS. 3, 4 and 5. The spaced cylindrical segments 54 have cylindrical sheet supporting surfaces 55 and the segments 54 will also be referred to as segmentsor discs associated with the front edge grippers. Positioned between the cylindrical segments 54 are other cylindrical segments 56 associated with the tail edge grippers and will also be referred to as segments or discs associated with the tail edge grippers. The discs 56 also have cylindrical sheet supporting surfaces 57 and are adjustably mounted on the shaft 48. The discs 56 are arranged to rotate about the shaft 48. The discs 56 are arranged to rotate about the shaft 48 to increase or decrease the peripheral distance around the cylinder between the front edge grippers 42 and tail edge grippers 44.

The end discs 56' adjacent to the

frames

50 and 52 are illustrated in FIGS. 3 and 5. The end discs 56 have bores 58 therethrough for receiving the tail edge gripper support shaft 60 and bores 62 to receive the tail edge gripper actuator shaft 64. The intermediate discs 56, as illustrated in FIG. 4, are connected to the end discs 56' by the angle 66 extending longitudinally in the cylinder 26 and secured to pads 68 on each of the discs 56 and 56'. With this arrangement rotation of the end discs 56' about the shaft 48 rotate all of the

discs

56 and 56 the same amount, so that all of the tail edge grippers 44 remain aligned linearly in various positions of adjustment of the tail edge grippers 44 to the front edge grippers 42.

The discs 56 and 56' are rotated about the shaft by an adjustment mechanism illustrated in FIGS. 3, 5, 7 and 8. The end discs 56' include a gear segment 70 that meshes with a pair of gears 72 mounted on shaft 74. The shaft 74 is, in turn, journaled in aperture 76 in fixed shaft support 75 located adjacent the end discs 56 and nonrotatably secured to the shaft 48 by means of pin 77, as illustrated in dotted line in FIG. 5. With this arrangement the rotation of gear 72, because of its meshing relation with the gear segment 70, rotates the end discs 56' about the shaft 48 to change the peripheral distance between the tail edge grippers 44 and the front edge grippers 42. The manner in which the tail edge grippers 44 are rotated about the shaft 48 to reduce the distance between the tail edge grippers 44 and the front edge grippers 42 is illustrated in phantom lines in FIG. 4.

The shaft 74 has an adjusting gear 78 (FIGS. 7 and 8) secured to an end portion thereof adjacent the drive side of the press. The gear 78 meshes with a worm gear 80 mounted on a shaft 82. The shaft 82 is, in turn, supported on a shaft support 84 secured to the adjusting shaft support 75. The shaft 82 has an end portion arranged to be engaged by a crank to rotate the gear 80 which, in turn, through gear 78 rotates adjusting shaft 74. The rotation of shaft 74 rotates the gears 72 to thus rotate the end discs 56' and the intermediate discs 56 connected thereto to change the peripheral distance between the front edge grippers 42 and the tail edge grippers 44.

As illustrated in FIG. 9, the tail edge gripper support shaft 60 is arranged to rotate or revolve relative to the main shaft 48, so that the tail grippers revolve with the shaft 60 and make one complete revolution per revolution of the shaft 48. The tail edge gripper support shaft and the tail edge grippers 44 revolve at a variable angular velocity during the revolution of the transfer cylinder main shaft 48 to extend the tail edge grippers beyond the periphery of the transfer cylinder 26, as

later described. The rotation of the tail edge gripper support shaft 60 is controlled by a cam and gear mechanism illustrated in FIGS. 2 and 5.

Referring to FIG. 5, the tail edge gripper support shaft 60 adjacent the drive side has a spur gear 86 nonrotatably secured thereto. The spur gear 86 meshes with a spur gear of reduced diameter 88 rotatably mounted on a suitable shaft 90 positioned radially inwardly of the tail edge gripper support shaft 60. Nonrotatably secured to gear 88 is a large spur gear 92 which meshes with a ring gear 94 that extends around the transfer cylinder shaft 48. The ring gear 94 is, in turn, connected to the end of a cylindrical member 96 that has a second ring gear 98 on the outboard end adjacent the frame 52. The cylindrical member 96 is supported by bearings on shaft 48.

A spur gear 100 is nonrotatably mounted to a smaller diameter gear 104. Gear 104 is rotatably mounted to shaft 102 journaled in the side frame 52. An arm 106 extends around the transfer cylinder shaft 48 and has a gear segment 108 meshing with the spur gear 104. The arm 106 has a bore 110 through which shaft 112 extends. The shaft 112 is nonrotatably secured to the arm 106 and is rotatably journaled in bore 114 of side frame 52. A leverarm 116 is nonrotatably secured to the other end of shaft 112 and has a cam follower 118 secured thereto. The cam follower 118 is, in turn. positioned in the endless cam track 120 on gear 122. The gear 122 is secured to drive gear 124 which rotates therewith. The gear 122 is adjustable radially on gear 124 for different size sheets. The gear 124 is secured to the transfer cylinder shaft 48 ,and transmits rotation to shaft 48 at a constant angular velocity. The cam follower 118, by means of cam track 120, pivots the arm 116 to oscillate the shaft 112 and through the arm 106 with gear segment 108 and

gear train

104, 100, 98, 94, 92, 88 and 86 revolves the tail edge gripper support shaft 60 at a non-uniform angular velocity to position the tail edge gripper shaft as illustrated in FIG. 9.

The tail edge grippers generally designated by the numeral 44 are illustrated in detail in FIGS. 4, 9, 9a and 9b and include a first arm 126 that has an end portion 128 with a semi-circular recess 130 having substantially the same diameter as the tail edge gripper support shaft 60 and longitudinally threaded bores 132 therethrough. A clamp end portion 134 has a similar circular recessed portion 136 and longitudinal bores 138 therethrough. The clamp end portion 134 is positioned in overlying relation to the arm end portion 128 and bolts 140 extend through the respective apertures to nonrotatably clamp the arm 126 to the tail edge gripper support shaft 60. The arm 126 has an aperture 142 intermediate the end portions and a gripper pad end portion 144 on gripper pad 144. A pin 152 extends through the lower portion of arm 150 and is secured at the other end to the enlarged end portion 128 of arm 126. A spring 154 is positioned between the arm 150 and the other end portion 128 of arm 126 and is arranged as viewed .in FIG. 4 to pivot the arm 146 in a clockwise direction to move the gripper finger 148 away from the gripper pad l44 to thus open the tail edge grippers 44. With this arrangement, the spring 154 continually urges the gripper finger 148 away from the gripper pad 144.

A plate member 156 is secured to the arm 146 and is arranged to pivot therewith about the pivot pin 149 and has a cam follower 158 thereon. A spring 159 is positioned on pin 161 and the pin 161 is positioned in recess 163 in plate 156. The pin 161 is secured to arm 146 and is operable to adjust the gripper 44 for different sheet thickness. The cam follower 158 is arranged to abut a surface of a cam 160 rotatably positioned on the tail edge gripper support shaft 60. With this arrngement, the spring 154 urges the gripper finger 148 toward an open position and further urges the cam follower 158 into abutting relation with the surface of the cam 160.

The cam 160, as illustrated in FIGS. 3, 9 and 9b, has a first arcuate surface 162 which is spaced a sufficient distance from the axis of shaft 60 to maintain the tail edge grippers 44 in a closed position where the gripper finger 148 abuts the gripper pad 144. The cam 160 has other cam surfaces 164, which permit the gripper fin-p ger 148 to move from a full open position to a full closed position, and a surface 166 that permits the gripper finger l48'to move into a full open position under the tension exerted by the spring 154. With this arrangement the tail edge grippers 44 are opened and closed by the relative position of the cam discs 160 associated with each tail edge gripper 44. The discs 160 are rotatably positioned on the tail edge gripper support shaft 60 so that the cams 160 can rotate about the shaft 60.

The relative position of the cams 160 on the tail edge gripper support shaft 60 is controlled by shaft 64 illustrated in FIGS. 3, 4, 9 and 9b. The tail edge gripper actuator shaft 64 has a plurality of levers 168 nonrotatably secured thereto. The levers 168 are connected at their end portion by means of rods 170 to the respective cams 160. With this arrangement rotation of shaft 64 relative to shaft 60 rotates the cam 160 to open and close the tail edge grippers 44. The shaft 64 is suitably journaled in the tail edge gripper end discs 56 and has a lever member 172 (FIGS. 2 and 3) connected to the end portion adjacent the frame 50 on the operators side of the delivery mechanism. A cylindrical member 174 is journaled in an aperture 176 in side frame 50 and has an axial passageway to rotatably support the transfer cylinder main shaft 48. The cylindrical member 174 has an enlarged circular end portion 178 with an endless cam track 180 therein. A cam follower 182 is positioned in the cam track 180 and is rotatably connected to lever 172 that is, in turn, connected to the end portion of shaft 64. With this arrangement, the cam follower 182 follows the endless cam track 180 in the fixed member 174 and pivots the arm 172 to thus rotate the shaft 64 with a preselected angular velocity to open the tail edge grippers 44 as the pad 144 of tail edge grippers 44 moves into underlying relation with the tail edge of the sheet and to thereafter close the tail edge grippers 44 to engage the sheet. Cam track 180 holds lever 168 stationary, as tail end gripper 44 rotates outward from transfer cylinder 26 as previously described, and cam follower 158 moves across surface 162 of cam 160. When the sheet has been conveyed to a position in substantially overlying relationship with the pile, cam follower 158 leaves cam surface 162 and tail end gripper 44 opens to release the sheet.

The sheet front edge grippers 42 are secured to a block 184 that is, in turn, secured to the nonrotatable member 75 which is pinned to shaft 48 (FIG. 7) by means of bolts. The front edge grippers include an angular member 186 having a radially extending edge portion 188 that serves as a gripper pad. Upstanding shaft supports 190 are secured to the pad 184 and have a front edge gripper pad actuator shaft 192 rotatably supported therein. The front grippers include a gripper arm 194 rotatably positioned on the shaft 192, as illustrated in FIGS. 3 and 4. The gripper arm 194 has a gripper finger 198 that is arranged to abut the gripper pad 188 to engage the front edge of a sheet therebetween. Member 200 is clampingly engaged on shaft 192 by bolts 196 and has a pin 202 connected thereto. A spring 204 is positioned between the head of the pin 202 and the surface of the gripper arm 194 for adjustment purposes.

Rotation of shaft 192 opens and closes the front edge grippers 42. The shaft 192 is journaled in the supports 190 and has an end portion 206 extending beyond the 5 end disc 56 adjacent the frame 52 on the delivery side of the delivery mechanism. The shaft end portion 206 is nonrotatably connected to a lever mechanism 208 that has a cam follower 210 rotatably secured thereto. A cam member 212 (FIGS. 2 and 6) is nonrotatably secured to a housing 214, which is, in turn, nonrotatably secured to the frame 52. The cam member 212 has an endless cam track 216 in which the cam follower 210 connected through lever 208 to shaft 192 is positioned.

Rotation of the transfer cylinder main shaft 48 moves the cam follower 210 in the cam track 216. The configuration of cam track 216 opens the front edge grippers 42 as the front edge grippers approach the point of tangency between the sprocket 22 and transfer cylinder 26 and closes the front edge grippers 42 on the front edge of the sheet as the sheet is transferred thereto from the transverse gripper bars 18 on chain 16. Thereafter, the cam track 216 maintains the grippers closed and in engagement with the sheet front edge portion until the transfer cylinder has revolved to a position where the grippers 36 are tangent to the transfer cylinder 26. At that location the cam track 216 opens the front edge grippers 42, so that the front edge of the sheet may be transferred to the grippers 36.

Referring to FIGS. 10 and 12 there is illustrated in top plan and side elevation a frame member generally designated by the numeral 218 that includes a side member 220 adjacent the press operators side frame 50 and a side member 222 adjacent the drive side frame 52. The frame 218 has transverse

members

224 and 226 secured to the

respective side members

220 and 222 in spaced relation to each other. An intermediate support member 227 is also positioned between

side members

220 and 222. A sprocket drive shaft 228 is suitably journaled in the

side frame members

220 and 222 in spaced relation to each other. A plurality of sprockets 230 are mounted on the sprocket drive shaft 228 for rotation therewith. Sprocket 232 connected to the end portion of shaft 228 is suitably connected to a drive mechanism and is arranged to rotateata preselected linear speed.

Extending rearwardly from the transverse member 224 are a plurality of sprocket supports 234 on which are rotatably mounted idler sprockets 236. A plurality of endless chains 34, previously described, are reeved about drive sprockets 230 and idler sprockets 236. The endless chains 34 are arranged to be driven at a preselected speed thatis coordinated with the press speed. Positioned adjacent to the respective chains 34 are a pluralityof endless gripper tracks-or guide 28in which the grippers generally designated bythe numeral 36 are positioned. As later described, the grippers 36 are connected to the adjacent endlessv chains, so that the endless chains 34 propel the grippers 36 in the gripper tracks 28.

The frame 218, which supports the endless chains 34 and gripper tracks 28, is movable longitudinally relative to the transfer cylinder 26, as illustrated in FIG. 12. The frame 218 has laterally extending shafts 238 with rollers 240 rotatably mounted thereon. The rollers 240 have annular V shaped recessed portions therein. As illustrated in FIG. 11, the rollers 240 are supported on members 242 that have an upstanding pointed portions 244 extending into the annular V-shaped recessed portions of roller 240. The members 242 are in turn, sup ported by the side frames 50 and 52. With this arrangement the frame 218 is movable longitudinally relative to the side frames 50 and 52 and the transfer cylinder 26 mounted thereon. The longitudinal adjustment of the frame 218 with the sheet delivery mechanism positioned thereon permits adjustment for delivery of different sized sheets without relative movement of the transfer cylinder 26.

As illustrated in FIG. 12, a beam member secured to the

frames

50 and 52 has a forwardly extending arm 246 on which cam members 248 are positioned. The cam members 248 are arranged to open and close the grippers generally designated by the numeral 36 so that the grippers 36 engage the leading edge of the sheet as it is transferred by the transfer cylinder 26. It should be noted that the cam member 248 remains fixed relative to the transfer cylinder 26 and longitudinal movement of frame 218 does not change the location at which the grippers 36 open to engage the sheet. Secured to the frame transverse member 226 are cam members 250 which are arranged to open the grippers 36 and release the front edge of the sheet as the sheet is deposited on the pile. It should be noted that the cam actuator 250 for opening the grippers 36 moves longitudinally with the frame 218.

One of the gripper tracks 28 is illustrated in detail in FIG. 12 and includes an outer rail 252 and a parallel inner rail 254 with a space 256 therebetween. The endless gripper track 28 has an intermediate lower portion 258 along which the gripper 36 is conveyed to a front portion generally designated by the numeral 260. The intermediate lower portion 258 is at substantially the same elevation as the lower strand of endless chain 34 and the gripper track front portion 260 deviated downwardly along an arcuate path from the path followed by the chain 34. The gripper 36 positioned in the gripper track thus follows the downwardly extending arcuate track front end portion 260 and, as later explained, slows down the forward velocity of the sheet as it is released.

The gripper 36 is illustrated in detail in FIGS. 13 l7 and includes a first plate member 262 with a pair of

rollers

264 and 266 positioned in the track opening 256. The rollers have shafts 268 and 270 that are secured to a second plate 272 on the opposite side of the gripper track 28. With this arrangement the plate 262 follows the path of the gripper track 256. The plate 262 has a depending arm portion 272 with a gripper finger 274 pivotally secured thereto about pivot pin 276. A lever 278is connected through pivot pin 276 to'gripper finger 274 and has a cam follower 280 secured to the end portion thereof. A gripper'pad 282 is secured to the plate depending arm portion 272 and the gripper finger 274 is arranged to abut the pad 282 and hold the front edge of the sheet therebetween. A spring 284 is connected to the gripper 274 and plate 262 to urge the gripper finger 274 into abutting relation with the gripper pad 282. With this arrangement the lever 278 through cam follower 280 is arranged to move the gripper finger 274 away from the gripper pad 282 in response to

cam surfaces

248 and 250.

The grippers 36 are connected to the respective adjacent chains 34 by an adjustable push rod 286 connected through ball type joints 288 to respective shafts 290 on chain 34 and shaft 270 on grippers 36. With this arrangement the grippers 36 are propelled by the respective adjacent chains 34 and open adjacent the transfer cylinder 26 to engage the front edge of the sheet and propel the sheet toward the front edge of the frame 218 where the cam 250 opens the grippers 36 and releases the sheet.

The grippers 36 by following the arcuate portion 260 of the cam track are arranged to slowdown the forward movement of the sheet as the chains 34 continue to move at the same velocity. As the gripper 36 is pushed into the arcuate portion 260 of track 256 one end of the rod 286 follows the chain path while the other end of the rod follows the arcuate portion 260 of the cam track. Thecounterclockwise motion of the push rod, as illustrated in FIGS. 16 and 17, slows down the entire gripper assembly relative to chain speed because the gripper assembly traverses a greater linear distance than the propelling chain reeved about

sprockets

230 and 236.

In addition, the two

rollers

264 and 266 in the gripper assembly 36 'follow the arcuate downwardly extending portion of the gripper track 260 and pivot the entire gripper 36 in a counterclockwise direction about the endof the push rod 286 that follows the cam or arcuate portion 260 of the cam track. The slowdown of the gripper 36 is accomplished by a combination of the push rod 286 pivoting counterclockwise and the gripper assembly 36 also pivoting counterclockwise. This slowdown of the grippers is arranged to match the slowdown of the tail grippers 44; thus maintaining the sheet straight as it is brought over the pile. The conveyor grippers 36 release the sheet first and then the tail end grippers 44 release the tail of the sheet thereafter. This permits the sheet to be deposited on the pile without flutter and the like.

According to the provisions of the patent statutes, we have explained the principle, preferred construction and mode of operation of our invention, and have illustrated and described what we now consider to represent its best embodiments. However, we desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

We claim:

1. A sheet transfer cylinder comprising,

a cylinder shaft rotatably journaled in a frame,

a sheet front edge gripper shaft positioned in parallel spaced relation to said cylinder shaft and supported by said cylinder shaft for rotation therewith,

sheet front edge gripper means secured to said sheet front edge gripper shaft and arranged to engage the front edge of a sheet,

means to rotate said sheet front edge gripper shaft to open and close said front edge gripper means at preselected radial angular positions of said cylinder shaft,

a sheet tail edge gripper shaftpositioned in parallel spaced relation to said cylinder shaft and said front edge gripper shaft,

means supporting said tail edge gripper shaft for rotation with said cylinder shaft,

sheet supporting means having a cylindrical sheet supporting surface,

tail edge gripper means secured to said tail edge gripper shaft and arranged to engage the tail edge of a sheet positioned on said sheet supporting surface,

means to open and close said tail edge gripper means at preselected radial angular positions of said cylinder shaft including a tail edge gripper means actuator shaft positioned in spaced parallel relation to said tail edge gripper shaft and a cam member rotatably positioned on said tail edge gripper shaft,

lever means connecting said actuator shaft and said cam member,

means to rotate said actuator shaft and said cam member relative to said gripper shaft to thereby open and close said tail edge gripper means, and means to extend said tail edge gripper means radially outwardly relative to said cylinder shaft beyond the periphery of said sheet supporting surface at preselected angular positions of said cylinder shaft.

2. A sheet transfer cylinder as set forth in claim 1 in which said means to extend said tail edge gripper means includes,

means to rotate said tail edge gripper shaft.

3. As set forth in claim 1 which includes,

means to move one of said gripper shafts toward and away from the other of said gripper shafts to increase and decrease the circumferential distance around said sheet supporting means and between said front edge gripper means and said tail edge gripper means.

4. As set forth in claim 3 in which said means supporting said tail edge gripper means includes,

support means mounted on said cylinder shaft and extending radially therefrom, said support means rotatable about said cylinder shaft, and

means to rotate said support means on said cylinder shaft through a preselected radial angle to move said tail edge gripper shaft towards and away from front edge gripper shaft.

5. As set forth in claim 4 in which said means to rotate said support means includes,

a gear segment on said support means,

an adjusting shaft positioned parallel to said cylinder shaft,

second support means nonrotatably supporting said adjusting shaft relative to said cylinder shaft,

said adjusting shaft rotatably supported in said second support means,

gear means nonrotatably secured to said adjusting shaft and meshing with said gear segment, and

means to rotate said gear means and thereby rotate said support means.

6. As set forth in claim 1 in which said tail edge gripper means includes,

a first arm member having a rear end portion nonro tatably secured to said gripper shaft and an upstanding gripper pad end portion,

a second arm member having 21 depending portion and a gripper pad end portion,

said second arm member depending portion pivotally connected to the intermediate portion of first arm member with said gripper pad end portions in overlying relation,

resilient means urging said pad end portion away from said other gripper pad end portion, and

cam means having a cam surface arranged to maintain said gripper pad end portions in abutting relation.

7. As set forth in claim 6 which includes,

a plate member secured to said arm member,

a cam follower connected to an end portion of said plate member,

a cam member rotatably positioned on said tail edge gripper shaft.

Claims

1. A sheet transfer cylinder comprising, a cylinder shaft rotatably journaled in a frame, a sheet front edge gripper shaft positioned in parallel spaced relation to said cylinder shaft and supported by said cylinder shaft for rotation therewith, sheet front edge gripper means secured to said sheet front edge gripper shaft and arranged to engage the front edge of a sheet, means to rotate said sheet front edge gripper shaft to open and close said front edge gripper means at preselected radial angular positions of said cylinder shaft, a sheet tail edge gripper shaft positioned in parallel spaced relation to said cylinder shaft and said front edge gripper shaft, means supporting said tail edge gripper shaft for rotation with said cylinder shaft, sheet supporting means having a cylindrical sheet supporting surface, tail edge gripper means secured to said tail edge gripper shaft and arranged to engage the tail edge of a sheet positioned on said sheet supporting surface, means to open and close said tail edge gripper means at preselected radial angular positions of said cylinder shaft including a tail edge gripper means actuator shaft positioned in spaced parallel relation to said tail edge gripper shaft and a cam member rotatably positioned on said tail edge gripper shaft, lever means connecting said actuator shaft and said cam member, means to rotate said actuator shaft and said cam member relative to said gripper shaft to thereby open and close said tail edge gripper means, and means to extend said tail edge gripper means radially outwardly relative to said cylinder shaft beyond the periphery of said sheet supporting surface at preselected angular positions of said cylinder shaft.

2. A sheet transfer cylinder as set forth in claim 1 in which said means to extend said tail edge gripper means includes, means to rotate said tail edge gripper shaft.

3. As set forth in claim 1 which includes, means to move one of said gripper shafts toward and away from the other of said gripper shafts to increase and decrease the circumferential distance around said sheet supporting means and between said front edge gripper means and said tail edge gripper means.

4. As set forth in claim 3 in which said means supporting said tail edge gripper means includes, support means mounted on said cylinder shaft and extending radially therefrom, said support means rotatable about said cylinder shaft, and means to rotate said support means on said cylinder shaft through a preselected radial angle to move said tail edge gripper shaft towards and away from front edge gripper shaft.

5. As set forth In claim 4 in which said means to rotate said support means includes, a gear segment on said support means, an adjusting shaft positioned parallel to said cylinder shaft, second support means nonrotatably supporting said adjusting shaft relative to said cylinder shaft, said adjusting shaft rotatably supported in said second support means, gear means nonrotatably secured to said adjusting shaft and meshing with said gear segment, and means to rotate said gear means and thereby rotate said support means.

6. As set forth in claim 1 in which said tail edge gripper means includes, a first arm member having a rear end portion nonrotatably secured to said gripper shaft and an upstanding gripper pad end portion, a second arm member having a depending portion and a gripper pad end portion, said second arm member depending portion pivotally connected to the intermediate portion of first arm member with said gripper pad end portions in overlying relation, resilient means urging said pad end portion away from said other gripper pad end portion, and cam means having a cam surface arranged to maintain said gripper pad end portions in abutting relation.

7. As set forth in claim 6 which includes, a plate member secured to said arm member, a cam follower connected to an end portion of said plate member, a cam member rotatably positioned on said tail edge gripper shaft.