Patent GB-291200-A (GB)
Title: Improvements in sheet delivery apparatus for use on printing machines
IPC: B65H29/36
Filed: 1927-04-19
Abstract: 291,200. Hodge Ranger, Ltd., and Ranger, A. W. April 19, 1927. Delivery apparatus; gripper mechanism. - In the sheet-delivery mechanism for printing-machines described in Specification 260,449, wherein delivery grippers deposit the sheet on to a roller-blind support from which the sheet is transferred to a reciprocating tape-carrier, the energy required to effect movement of the support is derived from the movements of the carrier. In one form, Figs. 1, 4, and 5, the apron 13 of the roller-blind support is fixed at one end to a spindle 14 having a spring wound thereon which allows of slight compensating movement thereof, the other end of the apron being wound on a roller 10 freely mounted on a spindle 11 to which it is connected by a coiled spring enclosed therein tending to move it away from the spindle 14 so. as to unroll the apron 13. On one end of the roller 10 is a pinion 27 engaging a rack 28 fixed to the main frame 2 of the delivery apparatus so that as the carrier 42 moves towards the machine 6 taking the roller 10 with it, the spring is caused to be compressed. Buffers 67 of leather or other resilient material are provided on the carrier 42 and on blocks 17 on the spindle 11, the blocks having mounted thereon a roller 18 adapted to be engaged by a catch 19 pivoted at 20 so as to hold the spindle 11 and roller 10 with the apron 13 rolled up until it is desired to release it. An arm 22 fixed to the pivot 20 has pivoted thereto a catch 23 controlled by a spring 25 and having an abutment 26 engaging the back edge of the catch. During the upward movement of the gripper arms 29 from the cylinder 6, a projecting plate 34, Fig. 1, attached to the abutment bar 33 of the grippers 32, 33 engages the catch 23 so that the latch 19 is lifted and the apron 13 is unwound under the action of the spring in the roller 10. During the reverse movement of the grippers, the latch 19 is not effected by the plate 34. The gripper jaw 32 is spring-pivoted at 31 on the arms 29 and has projections 36 engaged by a lever 37 pivoted at 38 on the arms 29 and carrying rollers 40, 39 adapted to be engaged by cams 43, 41 respectively so as to effect the opening and closing of the grippers. The cam 43 is fixed and the cam 41 is attached to the carrier 42. The arms 29 are mounted on a shaft 30 oscillated from a cam on the shaft of the cylinder 6 and controlled by a spring-enclosed rod 56 connected thereto by a crank 55. Mechanism for reciprocating the carriage 42 is adapted to give the carriage a relatively slow rate of travel towards the end of its outward stroke and consists of a link 61 connected to a crank 60 on a shaft 59<1> carrying a second crank 58<1> connected by a rod 57<1> to an actuating crank-shaft 56<1>. Cushioning means are provided for the moving parts of the roller-blind support and comprise a cylinder 68 fixed to the frame 2 and having a needle-valve 70 and a piston 71 loosely connected through a gland 76 and head 75 with a tube 72 fixed to one of the blocks 17, so that no cushioning takes place until the gland 76 contacts with the piston 71. A modification of the cushioning means consists in fixing the cylinder 68 to the carriage 42 and the head 75 is arranged to contact directly with the bracket 17, a coiled spring in the cylinder serving to control the movement of the piston 71. In a modified construction of mechanism for operating the roller-blind support shown in Fig. 8, a rod 81 is fixed to the bracket 17 and has a piston 82 moving in a cylinder 83 fixed to the carriage 42 so as to enclose a spring 84 between the piston 82 and the cylinder end 85. As the carriage 42 moves outwardly it compresses the spring 84 until the latch holding the support is released. The latch 85<1> in this case is held in engagement with a roller 88 on the block 17 by means of a spring 87<11>, and is moved about its pivot 86 so as to release the block 17 by means of a cam 90 on the machine shaft engaging a roller 89 on the end thereof. In order to cushion the support, a spring-pressed block 71 is mounted in the end of the cylinder 83 which has a small air outlet 69. The gripper arms 29 may be oscillated from the shaft 59<1> instead of from the machine shaft, for this purpose being provided with an arm 91, Fig. 10, having a roller 92 normally supported by a catch 93. When the catch is withdrawn bv cam means on the shaft 59<1> the roller 92 swings down into a recess 95 in a cam 94 mounted on the shaft 59<1> and moving in the direction of the arrow, so as to allow the grippers to seize the sheet. As the cam 94 rotates, it lifts the roller 92 on to a circular part 97 maintaining the grippers in the raised position during the movements of the apron 13 and carrier 42. A second catch 98 operated in conjunction with the tripping-lever of the press may be provided to hold the grippers permanently raised.