US3903795A - Device for clamping the trailing end portion of a sheet - Google Patents

Device for clamping the trailing end portion of a sheet Download PDF

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Publication number
US3903795A
US3903795A US365084A US36508473A US3903795A US 3903795 A US3903795 A US 3903795A US 365084 A US365084 A US 365084A US 36508473 A US36508473 A US 36508473A US 3903795 A US3903795 A US 3903795A
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Prior art keywords
drum
sheet
periphery
clamp member
supporters
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US365084A
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English (en)
Inventor
Minoru Suzuki
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Ricoh Co Ltd
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Ricoh Co Ltd
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41L—APPARATUS OR DEVICES FOR MANIFOLDING, DUPLICATING OR PRINTING FOR OFFICE OR OTHER COMMERCIAL PURPOSES; ADDRESSING MACHINES OR LIKE SERIES-PRINTING MACHINES
    • B41L29/00—Devices for attaching printing elements or formes to supports
    • B41L29/12—Devices for attaching printing elements or formes to supports for attaching flexible printing formes
    • B41L29/14—Clamping devices
    • B41L29/16—Clamping devices operating automatically during operation of rotary machines to attach the printing formes to the forme cylinders

Definitions

  • ABSTRACT A device comprising a groove-shaped clamp member receiving portion formed in one part of the periphery of a drum and disposed parallel to the axis of the drum, and an elongated clamp member adapted to be received in the groove-like receiving portion.
  • the device is elfective to clamp the trailing end portion of a sheet to the drum by tightly holding the trailing end portion in place by means of the clamp member c0op erating with the grooveshaped receiving portion after the leading end portion of the sheet is gripped by grip means while the drum is rotating.
  • This invention relates to a device for clamping the trailing end portion of a sheet which permits the sheet to be automatically mounted on a drum.
  • ink is applied to a master plate mounted on a master cylinder to form an ink image of the master sheet on a blanket cylinder, and a copy sheet is supplied between the blanket cylinder and an impression cylinder so that the ink image may be transferred from the blanket cylinder to the copy sheet.
  • a copy sheet is supplied between the blanket cylinder and an impression cylinder so that the ink image may be transferred from the blanket cylinder to the copy sheet.
  • FIG. 1 schematically shows essential portions of an offset duplicating machine in which 1 is a master cylinder on which one of master plates 2 is mounted thereon. and 3 is a blanket cylinder to which an impression cylinder 4 is adapted to be brought into pressing engagement, with a copy sheet 5 being interposed between the blanket cylinder 3 and the impression cylinder 4.
  • One of the master plates 2 on a plate feed tray 6 is supplied by a plate feed roller 7 to the master cylinder 1 and mounted on the periphery thereof.
  • An etching solution I] is applied to the master plate 2 on the master cylinder 1 by a roller 9 of an etching device 8 (See FIG. 2).
  • the etching solution is applied to the master plate so that ink may only adhere to image regions of the master plate 2 while non-image regions thereof remain free from ink.
  • etching solution is applied to the master plate 2
  • ink is applied thereto by an inking roller 13 of an inking device 12 to form an ink image of the master plate on the blanket cylinder 3.
  • copy sheets 5 are supplied one after another between the blanket cylinder 3 and impression cylinder 4 by a sheet feed roller 14 so that duplicates of the master plate 2 can be produced.
  • Printed copy sheets are discharged from the printing apparatus 15. After a predetermined number of copy sheets have been printed, the master plate 2 mounted on the master cylinder 1 is discharged by a plate discharge roller 16 and ejected on to a plate discharge tray 17. At the same time the ink image on the blanket cylinder 3 is cleaned by a cleaning device (not shown).
  • grip claw means 18 is arranged in a recess la formed in the periphery of the master cylinder 1 to bring the leading end portion of the master plate 2 into pressing engagement with the periphery of the master cylinder 1 when the master plate 2 is mounted on the master cylinder I.
  • the leading end portion of the master plate 2 mounted on the master cylinder 1 is held tightly in position by the grip claw means as aforementioned. but its trailing end portion 2a is not clamped to the periphery of the master cylinder and is free to move.
  • the etching solution 1] When the etching solution 1] is applied to the master plate 2. the latter becomes limp so that it can be made to conform to the shape of the periphery of the master cylinder.
  • the master plate can thus be brought into intimate contact with the periphery of the master cylinder, the trailing end portion of the master plate discngages the periphery of the master cylinder immediately after it is mounted on the master cylinder. so that the trailing end portion tends to come into contact with various devices disposed in the neighborhood of the master cylinder or the etching roller, inking roller. blanket cylinder and plate feed and discharge device, for example. As a result, the master plate tends to be soiled before printing is initiated.
  • This operation which is generally referred to as a pre-etching operation, is generally performed manually.
  • the conditions of the master plates treated by the pre-etching operation may vary from one master plate to another depending on the manner in which the operation is performed by different operators. [f the master plate is not thoroughly pre-etched, then its trailing end portion 2a is brought into contact with the inking roller 13 as shown in FIG. 2. As a result, ink adheres to nonimage regions of the master plate 2 and thus soils the plate, thereby interfering with the printing operation. in view of this, not only the leading end portion but also the trailing end portion should be positively clamped to the periphery of the master cylinder.
  • FIG. 3 shows essential portions of a duplicating machine provided with an electrophotographic copying apparatus adapted to prepare a master plate on the printing cylinder.
  • the copying apparatus comprises a charging device 21, an exposing device 22 and a developing device 23 disposed around the master cylinder 1.
  • a master plate 24 has on its surface an electrically insulating material layer which is uniformly charged by the charging device 21 as the master cylinder 1 rotates in the direction of an arrow. Then the charged surface of the master plate 24 is exposed to an optical image of an original (not shown) by the exposing device 22. As a result, an electrostatic latent image is formed on the master plate 24 and developed by the developing device 23 so that a visible image is formed on the master plate.
  • This invention has as its object the provision of a clamp device which permits a sheet supplied to a rotating drum to be automatically and positively clamped at its leading end portion and trailing end portion to the periphery of the drum.
  • a clamp device comprising a sheet clamp member disposed in a clamp member receiving portion formed on the periphery of a rotating drum wherein a sheet can pass under the clamp member if the latter is moved upwardly to its inoperative position when the former is supplied to the drum and the trailing end portion of the sheet can be automatically clamped to the periphery of the rotating drum if the clamp member is moved downwardly to its operative position.
  • the clamp device according to the invention is also effective to permit exposing of the sheet to an optical image of an original to be carried out satisfactorily to keep the image formed on the sheet from being blurred when a printing master is prepared on the rotating drum by means of an electrophotographic copying apparatus.
  • FIG. 1 is a schematic view of an offset duplicating machine
  • FIG. 2 is a side view of a master plate mounted on a master cylinder with its trailing end portion not clamped to the cylinder;
  • FIG. 3 is a schematic view of a rotating master cylinder and portions of an electrophotographic copying apparatus used to prepare a printing master on the periphery of the rotating master cylinder;
  • FIG. 4 is a front view of the device for clamping the trailing end portion of a sheet comprising one embodiment of the invention
  • FIG. 5 is a perspective view of the drum provided with the clamp device shown in FIG. 4;
  • FIG. 6 is a fragmentary sectional side view of the drum shown in FIG. 5, showing sheet grip claw means and sheet pushout means;
  • FIG. 7 is a front view of the sheet feed and discharge mechanisms adapted to feed a sheet to the drum and discharging the same therefrom;
  • FIG. 8 is a view of the drive system for driving sheet feed and sheet discharge rollers
  • FIG. 9 shows the manner in which the sheet feed mechanism shown in FIG. 7 operates when a sheet is fed
  • FIG. 10 shows the manner in which the sheet feed roller operates
  • FIG. 11 shows the manner in which the sheet feed mechanism shown in FIG. 7 and the clamp device shown in FIG. 4 operate;
  • FIG. 12 is a front view of the clamp member and one of the side wall cams
  • FIG. I3 shows the manner in which the clamp device shown in FIG. 4 operates
  • FIG. 14 shows the manner in which the sheet discharge mechanism shown in FIG. 7 operates
  • FIG. 15 is a front view of the guide roller
  • FIG. 16 shows the manner in which the clamp device shown in FIG. 4 operates when a sheet is discharged
  • FIG. I7 is a front view of the actuation roller and sheet discharge roller
  • FIG. I8 shows the manner in which the clamp device shown in FIG. 4 operates when a sheet is discharged
  • FIG. 19 is a front view of the clamp device comprising another embodiment of the invention, showing its essential portions;
  • FIG. 20 shows the manner in which the clamp device shown in FIG. 19 operates
  • FIG. 2! is a front view of the clamp device comprising another embodiment of the invention. showing its essential portions;
  • FIG. 22 shows the manner in which the clamp device shown in FIG. 21 operates.
  • FIG. 4 a drum 41 interposed between right and left side plates (not shown) of the duplicating machine is supported by a shaft 42 for rotation in the direction of an arrow 43.
  • a sheet feed cam 44 and a mounting plate 45 are rotatably supported by the shaft 42 in addition to the drum 41.
  • One clamp member supporter 46 is disposed on one side of the drum 4] while the other clamp member supporter 47 is disposed on the other side of the drum 4] as shown in FIG. 5.
  • the supporter 46 is formed therein with a plurality of slots 48, 48 loosely receiving therein shafts 49, 49 fixed to the sheet feed cam 44, so that the supporter 46 is mounted on the cam 44.
  • the other supporter 47 is mounted on the mounting plate 45 in like manner.
  • a clamp member SI which may be in the form of a rod is rotatably supported at its opposite ends by the supporters 46 and 47.
  • the drum 41 is formed in one part of its periphery with a recess 54 which defines side wall cams 55 and 56 on opposite side walls of the drum 4] and a groove-like receiving portion 57 at the rear end of the periphery of the drum 4] and disposed parallel to the axis of the drum 41.
  • the clamp member 51 is normally urged by the biasing forces of the aforementioned springs 52 and 53 into pressing engagement with valleys of the side wall earns 55 and 56 and the receiving portion 57 on the drum 4].
  • the supporters 46 and 47 and the sheet feed cam 44 and mounting plate 45 which support the supporters 46 and 47 can rotate in the same direction as the drum 41 when the latter is driven.
  • grip claw means 59 adapted to grip the leading end portion of a sheet 64 is supported at its base by screws 62 to a shaft 61 loosely supported at opposite ends by the opposite side walls of the drum 4] and urged by the biasing force of a spring (not shown) to bring its front end into pressing engagement with an offset portion 58 formed at the front end of the periphery of the drum 41.
  • a stopper 63 is secured at its base to the shaft 61 and formed at its free end with a bent portion 63a against which the sheet 64 abuts at its leading end to thereby position the sheet 64 relative to the drum 4] when a sheet is fed to the drum as subsequently to be described.
  • the offset portion 58 is contiguous with another offset portion 65 disposed at a lower level with which push-out means 66 is maintained in pressing engagement at its free end, the push-out means 66 being secured at its base to a lever 67.
  • the lever 67 is pivotally connected at one end through a shaft 72 to the free end of an arm 71, and is formed therein with a slot 68 loosely receiving therein a pin 69 affixed to one side wall of the drum 4].
  • the arm 7] is pivotally supported at its base by a shaft 73 supported by the opposite side walls of the drum 41.
  • a strip claw 75 for picking the sheet 64 off the periphery of the drum 4] and a sheet feed tray 76 are disposed rightwardly of the drum 41.
  • a sheet feed roller 77 is disposed above the sheet feed tray 76 and a sheet discharge roller 78 is disposed below the sheet feed tray 76, and an actuation roller 79 is interposed between the feed and discharge rollers 77 and 78.
  • the actuation roller 79 comprises major diameter portions 790 adapted to be rendered operative when sheet feed is carried out and minor diameter portions 79b adapted to be rendered operative when sheet discharge is carried out. Normally the minor diameter portions 79b are maintained in pressing engagement with the sheet discharge roller 78.
  • the actuation roller 79 is secured to a shaft 82 rotatably supported by a free end of a support arm 81 which is secured at its base to a shaft 83 supported by the left and right side plates.
  • the sheet feed tray 76 is formed therein with an opening 84 permitting the major diameter portions 790 (See FIG. 17) of the actuation roller to move thercthrough into engagement with the periphery of the sheet feed roller 77 when the support arm 81 moves clockwise about the shaft 83.
  • a gear 85 is rotatably mounted at an end portion of the shaft 83 and maintained in meshing engagement with pinions 86 and 87 which are secured to shafts 88 and 89 respectively.
  • the sheet feed roller 77 is secured to the shaft 88 while the sheet discharge roller 78 is secured to the shaft 89.
  • a sprocket wheel 91 is secured to one side of the gear 85 and another sprocket wheel 92 is mounted on the shaft 42 supporting the drum 4], with a chain 93 being trained over the two sprocket wheels 91 and 92.
  • a copy sheet feed cam follower 96 shown in FIG. 7 is secured at its base to an end portion of the shaft 83 to which the support arm 81 is secured as shown in FIG. 4.
  • the mechanism including the follower 96 shown in FIG. 7 is disposed outwardly of one of the side plates of the duplicating machine.
  • a sheet feed cam 97 adapted to actuate the sheet feed roller 77 is secured to the shaft 42 supporting the drum 41 and rotates in the same direction as the drum 4].
  • a roller 98 supported through a shaft by the follower 96 at its free end is positioned against the periphery of the cam 97.
  • the follower 96 is formed at its shorter arm with a bent portion 99 which is normally maintained in locking engagement with an engaging portion 102 of a sheet feed first actuation member 101 so as to preclude movement of the follower 96 in slaved relation to the cam 97 as the latter rotates.
  • the first actuation member 101 is pivotally sup ported by a shaft 103 connected to one of the side plates of the machine and normally urged to move counter clockwise about the shaft 103 by the biasing force of a spring 104 connected at one end to the member 10] and at the other end to the side plate. Normally a lower end portion of the member 101 is maintained in engagement with the bent portion 99 of the follower 96 to preclude the movement of the follower 96.
  • a spring 105 is connected at one end to a right end portion of the first actuation member 101 and at the other end to an actuator 107 for a sheet feed solenoid 106.
  • a sheet feed second actuation member 108 Disposed below the follower 96 is a sheet feed second actuation member 108 which is secured at its base to a shaft 109 (See FIG. 14) loosely supported by the side plates of the machine.
  • a spring 113 is connected at one end to a free end of the member 108 and at the other end to an actuator 112 for a sheet discharge solenoid 111.
  • a stopper 114 for limiting the range of move ment of the member 108 is disposed below the latter.
  • a spring 115 for returning the member 108 to its original position is connected at one end to the member 108 and at the other end to the side plate of the machine.
  • a loop 118 attached to one end of a connector 117 is hitched to a pin 116 affixed to the second actuation member 108.
  • the connector 117 is pivotally supported at the other end by a pin 119 affixed to the first actuation member 101 which is formed at its upper left end with a hook 12] adapted to engage a pin 123 affixed to one end portion of a short arm 122.
  • a compression spring 124 is connected at one end to the other end of the short arm 122 and at the other end to the follower 96.
  • the short arm 122 is secured to a shaft 125 loosely supported by the side plates of the machine.
  • the shaft 125 also supports a pair of lock levers 126 at their bases.
  • one of the lock levers 126 is shown as being formed at its free end with a hook 127 adapted to catch hold of a pin 128 affixed to the clamp member supporter 46 to temporarily interrupt the movement of the supporter 46.
  • the hook 127 is disposed in a position in which it is spaced apart from the path of movement of the pin 128 affixed to the supporter 46.
  • a sheet discharge cam 131 is secured at its base to the shaft 109 to which the second actuation member 108 is secured as shown in FIG. 7.
  • the sheet discharge cam 131 is urged by the biasing force of the spring 115 (See FIG. 7) to bring its lower side edge into pressing engagement with a shaft 133 which pivotally supports a release member 132.
  • a pin 134 affixed to an end portion of the release member 132 is maintained in pressing engagement with the sheet discharge cam 131 by the biasing force of a compression spring 136 connected at one end to the pin 134 and at the other end to a pin affixed to the sheet discharge cam 13].
  • a sheet feed follower 138 is secured at its base as shown in FIG. 4 to an end portion of the shaft 61 mounting the grip claw means 59 as shown in FIG. 5 and FIG. 6.
  • a roller 139 supported through a shaft by the follower 138 at its free end is positioned against the periphery of the sheet feed cam 44.
  • a sheet discharge follower 141 is secured as shown in FIG. 4 to an end portion of the shaft 73 mounting the arm 71 as shown in FIG. 6.
  • the follower 141 supports at one end through a shaft a roller 142 adapted to cooperate with the sheet discharge cam 13], and is positioned at the other end against a pin 145 affixed to the underside of the follower 138.
  • a lever 146 is secured at its base to the shaft 133 mounting the release member 132, and
  • the support arm 81 (See FIG. 4) adapted to move as a unit with the follower 96 moves clockwise about the shaft 83 into the position shown in FIG. 10.
  • This causes the major diameter portions 79a of the actuation roller 79 to bring the leading end portion of the sheet 64 into pressing engagement with the sheet feed roller 77.
  • the sheet 64 is fed to the drum 4i by the sheet feed roller 77 rotating in the direction of the arrow 94 at all times and the actuation roller 79 rotating in slaved relation to the sheet feed roller 77.
  • the clamp member 51 moves from the valleys of the side wall earns 55 and 56 to their crests and along the periphery of the drum 4]. Thus the sheet 64 moves under the clamp member 51 and rotates with the drum 4].
  • the sheet feed solenoid 106 shown in FIG. 7 remains emergized for a short time interval.
  • the first actuation member 10 tends to be restored to its original position by the biasing force of the spring I04.
  • the follower 96 is restored to its original position by the rotating cam 97.
  • the first actuation member 101 is also restored to its original position as shown in FIG. I] and locks the follower 96. That is, after the leading end portion of the sheet 64 is clamped to the periphery of the drum 4], the actuation roller 79 is returned from the position shown in FIG. 10 to the position shown in FIG. 4, thereby ending the feeding of the sheet 64.
  • the clamp member 51 is brought into engagement with the valleys of the side wall earns 55 and 56 and the receiving portion 57 (See FIG. 6) on the drum 4] so as to clamp a trailing end portion 640 of the sheet 64 (See FIG. 6) to the periphery of the drum 41 as shown in FIG. 13.
  • the clamp member 51 performs the aforementioned clamping function as the clamp members supporters 46 and 47 supporting the clamp member 51 are urged by the springs 52 and 53 respectively to move toward the center axis of the drum 41 and are restored to their original positions.
  • the sheet discharge solenoid 111 shown in FIG. 7 is energized when instructions are given to discharge the sheet 64 from the drum 41.
  • the second actuation member 108 moves clockwise about the shaft 109 and the sheet discharge cam 131 (See FIG. 4) adapted to act as a unit with the member 108 also moves clockwise.
  • the pin 134 on the release member 132 is brought into engagement with an offset portion 137 formed in the cam 131 and the release member 132 moves counter clockwise about the shaft 133, so that the cam 131 and release member 132 moves from their positions shown in FIG. 4 to their positions shown in FIG. 14.
  • the lever 146 adapted to move as a unit with the member 132 also moves counter clockwise to its position shown in FIG. 15, so as to bring the guide roller 147 into pressing engagement with the periphery of the drum 41.
  • the sheet discharge solenoid lll remains energized for a short time interval.
  • restoration of the second actuation member 108 and sheet discharge cam 131 by the biasing force of the spring is precluded by the pin 134 on the release member 132 being maintained in pressing engagement with the offset portion 137 of the sheet discharge cam 13] (See FIG. 7).
  • Actuation of the second actuation member 108 moves the first actuation member 101 clockwise through the connector 117 to its position shown in FIG. 14.
  • the first actuation member 10] moves to an extent such that the bent portion 99 of the follower 96 is not released from engagement with the engaging portion I02 of the member 101.
  • the follower 96 is restrained by the first actuation member 101 although the short arm 122 secured to the shaft supporting the lock levers I26 is released.
  • the support arm 81 adapted to act as a unit with the follower 96 remains in its position shown in FIG. 4, so that the minor diameter portions 79b of the actuation roller 79 rotate counter clockwise in slaved relation while being maintaincd in pressing engagement with the sheet discharge roller 78.
  • FIG. 14 shows the elements involved in sheet dis charge being ready for action.
  • Rotation of the drum 41 in the direction of the arrow 43 results in the roller 142 being pushed and moved by an upper side edge 131a of the sheet discharge cam I31 toward the central portion of the drum 41 as shown in FIG. 16. That is, the follower I41 supporting the roller I42 moves clockwise about the shaft 73 into a position shown in FIG. 16 in which it pushes and moves at its free end the pin 145 so as to cause the follower I38 mounting the pin 145 to move counter clockwise about the shaft 61.
  • the grip claw means 59 adapted to move as a unit with the follower 138 is brought to an open position and releases the leading end portion 64b of the sheet 64.
  • the arm 71 (See FIG. 6) adapted to act as a unit with the follower 141 also moves clockwise and moves the free end of the pushout means 66 outwardly so as to push the leading end portion 64b outwardly of the periphery of the drum 41.
  • the leading end portion 64b is picked off the periphery of the drum 4] by the pick-off claw 7S and guided by the sheet discharge roller 78 and the minor diameter portions 79a of the actuation roller 79 to move in the direction of an arrow as shown in FIG. 18.
  • the roller 142 kicks a free end 132a of the release member 132 disposed in the path of movement of the roller 142 and restores the release member 132 to its original position as shown in FIG. 18.
  • the guide roller 147 is moved away from the periphery of the drum 41 and the sheet discharge cam 131 is released from restraint, so that the cam 131 and the second actuation member 108 adapted to act as a unit with the cam 131 are restored to their original positions by the biasing force of the spring 115 (See FIG. 7).
  • show other embodiments of the invention.
  • like reference characters designate similar parts which function in the same manner.
  • a pair of cams I51 (only one cam being shown) are each secured to one of the two sides of the drum 4].
  • a clamp member 153 is main taincd in engagement with a recess 152 formed by side edges 151 of the cams 151 (only one side edge 1511: being shown) and the receiving portion 57 on the periphery of the drum 41.
  • the clamp member 153 is sup ported at opposite ends by a pair of clamp member supporters 154 (only one supporter being shown) at their free end.
  • the clamp member supporters 154 are each pivotally supported at their base by a shaft 156 which supports the free end of a support arm 155 pivotally supported at its base by the shaft 42 supporting the drum 41.
  • Each supporter 154 is urged to move clockwise about the shaft 156 by the biasing force of a spring 157 connected at one end to the supporter 154 and at the other end to the support arm 155.
  • the cams 151 perform the same function as the side wall cams and 56 shown in FIG. 5, and the clamp member 153 performs the same function as the clamp member 51 and pin 128 shown in FIG. 4.
  • the lock lever 126 moves counter clockwise from the position shown in FIG. 19.
  • the clamp member 153 moving in the direction of the arrow 43 together with the drum 41 is engaged and locked by the hook 127, so that the supporters 154 and support arms are restrained from moving with the drum 41.
  • the clamp member 153 kept from moving with the drum 41 moves along an edge 151a of each cam 151, so that it is released from engagement with the recess 152 and brought into engagement with the upper surface of the sheet 64 fed to the periphery of the drum 41 as shown in FIG. 20.
  • One complete rotation of the drum 41 brings the clamp member 153 into engagement with the recess 152 again, so that the trailing end portion of the sheet 64 is clamped by the clamp member 153 to the periphery of the drum 41.
  • a pair of cams 161 are each secured to one of the two sides of the drum 41.
  • Each cam 161 has a major diameter portion I6la with which a roller 162 is maintained in pressing engagement.
  • the roller 162 is supported at one end portion of a clamp member supporter 163 which is pivotally supported substantially at its central portion by a shaft 165 connected to the free end of a support arm I64 pivotally supported at its base by the shaft 42 supporting the drum 41.
  • the supporter 163 is urged to move counter clockwise about the shaft 165 by the biasing force of a spring 166 connected at one end to the support arm 164 and at the other end to the cam 161.
  • the supporter 163 is formed at the other end portion with an inwardly bent portion 163a which is maintained in pressing engagement with a recess 167 formed on the periphery of the drum 41 and having a resilient member 168 embedded therein.
  • the inwardly bent portion 163a presses against the resilient member 168 when the roller 162 is maintained in engagement with the major diameter portion 1610 of the cam 161.
  • a hold-down roller 169 is disposed above the periphery of the drum 41.
  • the roller 169 is adapted to be brought into pressing engagement with the periphery of the drum 41 when a sheet is fed to the drum, but is normally disposed in a position in which it is spaced apart from the periphery of the drum 41.
  • the clamp member supporter 163 has affixed thereon a pin 171 which is adapted to be engaged and locked by the hook 127 of the lock lever 126 (See FIG. 4 and FIG. 19) when the latter is moved to its operative position.
  • the sheet 64 moves under the inwardly bent portion 1630 as shown in FlG. 22 and is brought into intimate contact with the periphery of the drum 41 by the holddown roller 169.
  • the sheet 64 has its trailing end portion clamped by the inwardly bent portion 16311 of the supporter 163 to the drum 4] as the inwardly bent portion 163a is again brought into engagement with the recess 167 on the periphery of the drum 41 after the drum has made one complete revolution.
  • the hold-down roller 169 is moved from its operative position on the periphery of the drum 41 to its inoperative position in which it is spaced apart from the drum 41 by suitable means (not shown).
  • Means for supporting and actuating the clamp member for clamping the trailing end portion of the sheet 64 may comprise, in addition to the clamp member supporters 46 and 47 shown in FIG. 4, the clamp member supporters 154 adapted to be actuated by the cams 151 as shown in FIG. 19 and the clamp member supporters 163 adapted to be actuated by the cams 161 as shown in FIG. 21.
  • Means for clamping the trailing end portion of the sheet 64 to the drum 41 may comprise, in addition to the clamp member 51 shown in H0. 4, the clamp member 153 shown in FIG. 19 and the inwardly bent portions 1630 of the clamp member supporters 163 shown in H0. 21.
  • c. means for moving the elongated clamp member out of the recessed portion while the sheet is being positioned about the periphery of the drum and for moving the elongated clamp member into engagement with the recessed portion while the trailing margin is disposed therein after the sheet has been positioned about the periphery of the drum to clamp the trailing margin to the periphery of the drum.
  • said means for moving the elongated elamp member into and out of engagement with the recessed portion comprises a pair of supporters each holding one of the opposite ends of the clamp member and mounted on one of the opposite ends of the drum for rotational and radial movement relative to the drum, means for restraining the supporters from rotating while the leading margin of the sheet is being clamped to the periphery of the drum, cam means for moving the supporters radially of the drum while the supporters are restrained from rotating so as to move the clamp member radially outwardly from the periphery of the drum, and cam means for releasing the supporters for rotational movement together with the drum after the trailing margin of the sheet is held in the recessed portion.
  • a device further comprising a resilient member disposed in the recessed portion of the drum and positioned to be engaged by the clamp member to firmly hold the trailing margin of the sheet.

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  • Feeding Of Articles By Means Other Than Belts Or Rollers (AREA)
  • Supply, Installation And Extraction Of Printed Sheets Or Plates (AREA)
  • Discharging, Photosensitive Material Shape In Electrophotography (AREA)
  • Discharge By Other Means (AREA)
US365084A 1972-06-17 1973-05-30 Device for clamping the trailing end portion of a sheet Expired - Lifetime US3903795A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP6071472A JPS5513911B2 (de) 1972-06-17 1972-06-17

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US3903795A true US3903795A (en) 1975-09-09

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US365084A Expired - Lifetime US3903795A (en) 1972-06-17 1973-05-30 Device for clamping the trailing end portion of a sheet

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JP (1) JPS5513911B2 (de)
GB (1) GB1427573A (de)

Cited By (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4183652A (en) * 1977-04-30 1980-01-15 Ricoh Company, Ltd. Photoconductor sheet clamp apparatus
US4192603A (en) * 1978-09-27 1980-03-11 Xerox Corporation Replenishable photoconductor system
US4219272A (en) * 1978-04-20 1980-08-26 Olympia Werke Ag Electrophotographic copier with replaceable photoconductive sheet
WO1980002466A1 (en) * 1979-05-10 1980-11-13 Eltra Corp Electrophotographic apparatus providing output from a typesetter
US4240739A (en) * 1976-05-17 1980-12-23 Canon Kabushiki Kaisha Electrostatic copying apparatus
US4277164A (en) * 1978-07-14 1981-07-07 Olympia Werke Ag Photocopier photoconductive sheet holding device
US4824096A (en) * 1987-07-17 1989-04-25 Polaroid Corporation Sheet clamp counterbalancing system for high speed sheet handling drums
US4875069A (en) * 1987-01-19 1989-10-17 Canon Kabushiki Kaisha Anti-fouling device for sheet gripper
US4900008A (en) * 1986-12-22 1990-02-13 Polaroid Corporation Sheet clamping arrangement for rotatable drums
US4926216A (en) * 1988-03-18 1990-05-15 Hitachi Koki Company Feeder of sheet-like photo-sensitive material
US4952750A (en) * 1988-05-05 1990-08-28 Krupp Koppers Gmbh Process for making p-xylene with a purity of at least 99.5%
US5107350A (en) * 1989-06-20 1992-04-21 Kabushiki Kaisha Toshiba Image reading apparatus for optically reading the contents of a conveyed document and obtaining image signal information
US5111744A (en) * 1989-12-09 1992-05-12 Koenig & Bauer Aktiengesellschaft Method and apparatus for automatically changing a printing plate
US5127328A (en) * 1989-12-09 1992-07-07 Koenig & Bauer Aktiengesellschaft Method and apparatus for automatically feeding a printing plate
US5181466A (en) * 1991-03-29 1993-01-26 Tokyo Electric Co., Ltd. Offset printing machine having automatically releasably clamped blanket sheet
US5324023A (en) * 1993-05-24 1994-06-28 Eastman Kodak Company Apparatus for securing flexible sheet material to a rotatable drum surface
US5325777A (en) * 1992-08-06 1994-07-05 Samsung Electronics Co., Ltd. Image forming apparatus and method
US5383401A (en) * 1994-02-22 1995-01-24 Heidelberg Druckmaschinen Ag Actuating device for clamping arrangement for printing plates in rotary printing presses
US5410391A (en) * 1993-04-22 1995-04-25 Toyo Ink Manufacturing Co., Ltd. Image-transfer apparatus with movable smoothing roller and image-transfer method
US5440983A (en) * 1993-09-08 1995-08-15 Heidelberger Druckmaschinen Swinging pregripper of a sheet-fed printing press
US5516096A (en) * 1994-05-10 1996-05-14 Polaroid Corporation Method and apparatus for securing a flexible sheet to a rotatable supporting surface
US5669043A (en) * 1992-09-30 1997-09-16 Hitachi Koki Co., Ltd. Film photoconductor holding mechanism
US5953993A (en) * 1997-03-27 1999-09-21 Ryobi, Ltd. Apparatus for driving a clamping device for fixing a plate on a plate cylinder of a printing machine
US6457407B2 (en) * 1999-12-16 2002-10-01 Heidelberger Druckmaschinen Ag Method and apparatus for adjusting cylinders in a printing machine
US20100189476A1 (en) * 2009-01-26 2010-07-29 Seiko Epson Corporation Image forming device and image forming method
US20110073611A1 (en) * 2008-06-24 2011-03-31 Oki Electric Industry Co., Ltd. Medium storing and advancing apparatus
US20110236081A1 (en) * 2010-03-29 2011-09-29 Fuji Xerox Co., Ltd. Image forming apparatus
US20130065742A1 (en) * 2010-08-25 2013-03-14 Alexander Feygelman Substrate support

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JPS4931402U (de) * 1972-06-17 1974-03-18
JPS5711782B2 (de) * 1974-02-26 1982-03-06
JPS5126109A (ja) * 1974-08-24 1976-03-03 Tokyo Aircraft Instr Co Jidoseihaninsatsukitoniokeru genbanjidochakudatsusochi
DE2557866B2 (de) * 1975-12-22 1977-11-03 Heidelberger Druckmaschinen Ag, 6900 Heidelberg Rotierende vorgreifertrommel
DE2906482C3 (de) * 1979-02-20 1981-11-12 Rotaprint Gmbh, 1000 Berlin Papierzuführung für Büro- und Offsetdruckmaschinen
JPS55124659A (en) * 1979-03-19 1980-09-25 Ricoh Co Ltd Master clamp device in printing press
JPS6060413U (ja) * 1983-06-10 1985-04-26 上田　正保 健康手袋
JPS62192515A (ja) * 1986-02-19 1987-08-24 Nippon Kokan Kk <Nkk> 溶銑運搬装置

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US2861862A (en) * 1953-06-27 1958-11-25 Philips Corp Dictation apparatus
US3348288A (en) * 1965-10-01 1967-10-24 Xerox Corp Drum clamp
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US2861862A (en) * 1953-06-27 1958-11-25 Philips Corp Dictation apparatus
US3460443A (en) * 1965-09-20 1969-08-12 Harris Intertype Corp Apparatus for operating on sheet material
US3348288A (en) * 1965-10-01 1967-10-24 Xerox Corp Drum clamp
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Cited By (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4240739A (en) * 1976-05-17 1980-12-23 Canon Kabushiki Kaisha Electrostatic copying apparatus
US4183652A (en) * 1977-04-30 1980-01-15 Ricoh Company, Ltd. Photoconductor sheet clamp apparatus
US4219272A (en) * 1978-04-20 1980-08-26 Olympia Werke Ag Electrophotographic copier with replaceable photoconductive sheet
US4277164A (en) * 1978-07-14 1981-07-07 Olympia Werke Ag Photocopier photoconductive sheet holding device
US4192603A (en) * 1978-09-27 1980-03-11 Xerox Corporation Replenishable photoconductor system
WO1980002466A1 (en) * 1979-05-10 1980-11-13 Eltra Corp Electrophotographic apparatus providing output from a typesetter
US4900008A (en) * 1986-12-22 1990-02-13 Polaroid Corporation Sheet clamping arrangement for rotatable drums
US4875069A (en) * 1987-01-19 1989-10-17 Canon Kabushiki Kaisha Anti-fouling device for sheet gripper
US4824096A (en) * 1987-07-17 1989-04-25 Polaroid Corporation Sheet clamp counterbalancing system for high speed sheet handling drums
US4926216A (en) * 1988-03-18 1990-05-15 Hitachi Koki Company Feeder of sheet-like photo-sensitive material
US4952750A (en) * 1988-05-05 1990-08-28 Krupp Koppers Gmbh Process for making p-xylene with a purity of at least 99.5%
US5107350A (en) * 1989-06-20 1992-04-21 Kabushiki Kaisha Toshiba Image reading apparatus for optically reading the contents of a conveyed document and obtaining image signal information
US5111744A (en) * 1989-12-09 1992-05-12 Koenig & Bauer Aktiengesellschaft Method and apparatus for automatically changing a printing plate
US5127328A (en) * 1989-12-09 1992-07-07 Koenig & Bauer Aktiengesellschaft Method and apparatus for automatically feeding a printing plate
AU644616B2 (en) * 1989-12-09 1993-12-16 Koenig & Bauer Aktiengesellschaft Procedure and device for automatically feeding in or feeding out a printing plate
US5181466A (en) * 1991-03-29 1993-01-26 Tokyo Electric Co., Ltd. Offset printing machine having automatically releasably clamped blanket sheet
US5325777A (en) * 1992-08-06 1994-07-05 Samsung Electronics Co., Ltd. Image forming apparatus and method
US5669043A (en) * 1992-09-30 1997-09-16 Hitachi Koki Co., Ltd. Film photoconductor holding mechanism
US5410391A (en) * 1993-04-22 1995-04-25 Toyo Ink Manufacturing Co., Ltd. Image-transfer apparatus with movable smoothing roller and image-transfer method
US5324023A (en) * 1993-05-24 1994-06-28 Eastman Kodak Company Apparatus for securing flexible sheet material to a rotatable drum surface
US5440983A (en) * 1993-09-08 1995-08-15 Heidelberger Druckmaschinen Swinging pregripper of a sheet-fed printing press
US5383401A (en) * 1994-02-22 1995-01-24 Heidelberg Druckmaschinen Ag Actuating device for clamping arrangement for printing plates in rotary printing presses
US5516096A (en) * 1994-05-10 1996-05-14 Polaroid Corporation Method and apparatus for securing a flexible sheet to a rotatable supporting surface
US5953993A (en) * 1997-03-27 1999-09-21 Ryobi, Ltd. Apparatus for driving a clamping device for fixing a plate on a plate cylinder of a printing machine
US6457407B2 (en) * 1999-12-16 2002-10-01 Heidelberger Druckmaschinen Ag Method and apparatus for adjusting cylinders in a printing machine
US20110073611A1 (en) * 2008-06-24 2011-03-31 Oki Electric Industry Co., Ltd. Medium storing and advancing apparatus
US9016611B2 (en) * 2008-06-24 2015-04-28 Oki Electric Industry Co., Ltd. Medium storing and advancing apparatus
US20100189476A1 (en) * 2009-01-26 2010-07-29 Seiko Epson Corporation Image forming device and image forming method
US20110236081A1 (en) * 2010-03-29 2011-09-29 Fuji Xerox Co., Ltd. Image forming apparatus
JP2011209466A (ja) * 2010-03-29 2011-10-20 Fuji Xerox Co Ltd 画像形成装置
US8369758B2 (en) * 2010-03-29 2013-02-05 Fuji Xerox Co., Ltd. Image forming apparatus including a rear-end holding member
US20130065742A1 (en) * 2010-08-25 2013-03-14 Alexander Feygelman Substrate support
US9624040B2 (en) * 2010-08-25 2017-04-18 Hewlett-Packard Development Company, L.P. Substrate support

Also Published As

Publication number Publication date
JPS5513911B2 (de) 1980-04-12
DE2330947B2 (de) 1976-05-13
DE2330947A1 (de) 1974-01-03
JPS4921210A (de) 1974-02-25
GB1427573A (en) 1976-03-10

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