Patent GB-695445-A (GB)
Title: Improvements in or relating to means for correlating the drives of a plurality of intermittently operated components, particularly paper feeding and cutting mechanisms
IPC: B41L47/24
Filed: 1949-10-14
Abstract: 695,445. Addressing-machines. ERICSSON BROS., Ltd., and SIMPSON, A. W. Jan. 10, 1951 [Oct. 14, 1949], No. 26456/49. Class 100(ii) [Also in Group XXIV] Apparatus for correlating the drives of two intermittently operated components, such as webfeed means, and cutting-means for the web, comprises a continuously-rotated member driven by a source of power, a driven member arranged to drive one component, a dog clutch interposed between the driving and driven members, a first electromagnetic relay arranged to cause the clutch to engage, means for disengaging the clutch and arresting the driven member precisely after a predetermined angular movement, and a second driven member arranged to drive the second component and to be driven through a second dog clutch under the control of a second electromagnetic relay operated as a result of the first driven member having rotated through a predetermined angular movement. The apparatus is described in connection with addressing-machines for feeding and printing forms which are subsequently cut off, and where the frequency of the cutting operation can be varied relatively to the printing. The actual printing, feeding, and cutting mechanisms are not described, but the feeding mechanism could be as described in Specification 649,199. In the construction shown in Fig. 1, which is a one-revolution clutch, a ratchet 12 and disc 13 are fixed and rotatable, respectively, on a driving shaft 10, the disc being normally held against rotation by a roller 16, on a spring-pressed lever 14, engaging a notch in the disc. A pawl 19 on the disc is normally prevented from engaging the ratchet 12, under the action of a spring 22, by a face 29 on a pivoted quadrant lever 25. The lever 25 is urged counterclockwise by a spring 27, but is normally retained by the engagement in a notch 30 therein of the armature 31 of a solenoid 32. A nose 28 in the lever 25 co-operates with an abutment 23 bolted to the disc. When the solenoid 32 is energized, the armature 31 is withdrawn, the lever 25 moves to the broken line position, the pawl 19 is released to engage the rotating ratchet 12, and the disc 13 is therefore driven, overcoming the detent lever 14. Towards the end of one complete revolution of the disc 13, the abutment 23 engages the nose 28 to move the lever 25 to full line position, the pawl 19 then engages the face 29 and is disengaged from the ratchet 12, and the disc is then arrested by the roller 16 of the lever 14. Two such clutches can be arranged as described below, one driving the web-feed means, and the other a cutting-means. In the arrangement shown in Figs. 2 and 6, there are two one-revolution clutches, similar to the kind shown in Fig. 1, arranged on a driving shaft 34. The first clutch comprises a ratchet 37, fixed to the shaft, and a disc 39, gear 40, and detent disc 41 arranged to rotate as one on the shaft. The second clutch comprises a ratchet 38, disc 42, gear 43, and detent disc 44. The detent discs 41, 44 are each notched for engagement by a roller on a detent lever as described above, while the discs 39, 42 carry spring-urged pawls 51, 52 adapted to engage ratchets 37, 38. A bridge member 57, arranged transversely of the frame 33, supports solenoids 58, 59 having armatures 60, 61 arranged to project into the paths of the pawls 51, 52, respectively. The gear 40 meshes with a gear 67 fixed on a shaft 62 adapted to drive the paper web in an addressing- machine through gears 69, 70, and the gear 43 meshes with a gear 68 secured to a co-axial shaft 63 adapted to drive a guillotine cutter for the web. A pawl 71 pivoted on the end of the shaft 62 engages a selector ratchet 73 to which two (or more) fibre selector cams 79, 80 are adjustably secured by screw and slot means 78, 77. The pawl 71 and a hack-stop 75 for the ratchet 73 are connected by a spring 74. These cams 79, 80 have lobes thereon adapted to actuate switch blades 81, 82, which can be set under either cam, or a pair of blades can be associated with each cam, and a rotary switch provided to select which cam functions. These switch blades complete the circuit of the solenoid 59. A snail cam 84, Fig. 2 adjustably secured to the paper-feed shaft 62 is adapted to rock vertically a stepped lever carrying a vertical link' 89, Fig. 7 (not shown) which is notched for engagement by a horizontal lever controlling a micro-switch in series with a knock-off solenoid 96 (not shown). The solenoid 58 is energized by the platen mechanism, and the solenoid 59 by the closing of the micro-switch and the switch blades 81 82. In operation, with both solenoids 58, 59 deenergized, their armatures 60, 61 hold the pawls 51, 52 out of engagement with the ratchets 37, 38, but when an impulse from the platen energizes the solenoid 58, the pawl 51 is released and the paperfeed shaft 62 driven for one revolution. During this revolution, the snail cam 84 rotates and causes the knock-off solenoid 96 and, consequently, the solenoid 59, to be energized exactly one revolution of the drive shaft 34 after the paper-feed shaft 62 has come to rest. Thus the pawl 52 is released, the guillotine shaft 63 is rotated'through onerevolution, and the web is therefore cut after each printing operation. Where the web is to be severed after two printing operations, a different selector cam (say 79) operates the switch blades 81, 82. Other selector cams can be employed to give further variations. In a modification, Fig. 8, employed in the above construction when very short forms are to be printed, and to facilitate alteration of the paperfeed, a plate assembly 100a is attached to the frame 33 over existing posts 101, Figs. 2 and 8, to replace the existing plate 100 and gear 70. A roller 104, on a spring-urged lever 102 pivoted on the plate 100a at 103, engages a snail cam 106 secured to the paper-feed shaft 62 whereby the lever is oscillated by the shaft. The lever 102 oscillates a rocker arm 109 provided with a pawl 112 engaging a ratchet 108 to which is secured a gear-wheel 107 adapted to drive the paper-web feed. The extent of oscillation of the rocker arm 109 is controlled by a stop-screw 114 carried by an adjustable arm 113, so that the paper-feed can be varied.