Patent GB-441492-A (GB)
Title: Improvements in or relating to paper feeding mechanism for tabulating and like machines
Filed: 1934-07-17
Abstract: 441,492. Typewriters &c. THOMAS, A., 11, Sandy Lane South, Wallington, Surrey. July 17, 1934, No. 20953. [Class 100 (iv)] Feed-roller rotation for blanking &c.-In a long-paper-feeding mechanism for tabulating and like machines, having feeding elements for the paper and rotary driving means therefor, the latter is intermittently actuated whereby intervals of rest of the driving means are produced in each of which a printing operation may be performed, and the feeding elements are mechanically connected to the driving means by mechanism which imparts to the feeding elements a continuous unidirectional relatively gradually accelerated and decelerated movement throughout each period of movement of the driving means. The long-paperfeed mechanism which is provided in addition to the ordinary line-spacing mechanism operates on feed rollers 4, 5, arranged above the platen 1 and adapted to take up the slack produced by the line-spacing mechanism before imparting the blank paper feed. The feed-rollers are driven from a shaft 9 which carries a ratchet adapted to be engaged by one or other of two pawls, both of which are carried by a disc adapted to be rotated by reciprocating racks 22, 23. During the upward movement of the racks, one pawl engages the ratchet while the second slips, and during the downward movement the former pawl slips while the second drives the ratchet. By this means, both the outward and inward movements effect a feed of the paper. The racks are connected at their lower ends to a member 24 which is adjustably supported by a screw 26 so as to permit adjustment of the stroke ; both racks may be adjusted simultaneously or they may be independently supported and adjusted. The screw 26 is supported in a bell-crank 31 which is oscillated by a connecting rod 32 connected at its lower end to a disc 35 which carries a gear 36, Fig. 6, meshing with a gear 48. The latter gear is adapted to be clutched to a continuously driven shaft 42 by a spring latch 49 which is carried by the gear and engages a recess in a collar fixed to the shaft and which can be disengaged therefrom by operating a lever 59. This lever carries a resilient latch stud 54, which when the lever is moved to the left is swung into the path of the latch 49 and disengages it from the collar on the shaft 42 when a check-pawl 70 engages a notch in a stop ring fast to the pinion 48 and holds it against movement. The pinion 48 makes a complete revolution in time with one revolution of the machine and during nine-tenths of this time the gear 36 turns through one half of a revolution and remains locked in position for the remaining tenth while a printing operation may be effected. To lock the gear 36, the teeth of the pinion 48 are cut away at 60 and a plate 61 provided on the pinion is formed with recesses 63, 64 co-operating with projections 65, 66 formed on plates 62, 62a fixed to the gear 36. When the mutilated part of the pinion 48 comes opposite a plate 62 or 62a, the gear 36 ceases to rotate and is held locked by the engagement of the projections 65, 66 until the first tooth at the end of the gap engages the gear 36 at which point the projection 65 engages the recess 63 and the gear is unlocked. This locking action takes place at the end of each half revolution of the wheel 36 and is also arranged to occur as the crank arm 32 passes through its dead-centre positions. At this time, the printing operation takes place and on account of the simple harmonic motion of the crank the paper feed recommences at slow speed, attains a maximum, and then slows down until it ceases for the next printing operation. Means are provided whereby the clutch of the long-paper-feed mechanism may operate when printing only grand-totals or sub-totals, or for each item, or may be disengaged completely, and to effect this there is provided a spring-pressed sliding rod 103 which when moved to the left in Fig. 1 is adapted to swing the control lever 59 to such a position that the gear 48 is clutched to the driving shaft for one machine cycle. Pivoted to the rod 103, Fig. 8, is a latch 109 adapted to co-operate with a pin 110 on a bracket secured to the sub-total link 100, and pivoted to a bell-crank 106 is a link 113 of which the upper part is slotted to engage a pin 114 carried by an arm on the grandtotal shaft 101. The link 113 carries a second pivoted latch 117 which is adapted to engage the pin 114. A cam plate 120 may be moved by a control arm 121 to one of four positions. In position D, a raised part of the cam plate 120 engages a pin 124 on the link 117 so that this link cannot engage with the pin 114 attached to the grand-total shaft and a similar part of the cam engages a pin 125 on the latch 109 so that the latter is out of the path of the sub-total link. In this position the paper-feed mechanism is not operated. When the control arm is in the position C, the pin 124 is in a low part of the cam plate and on operating the grand-total shaft, the latch 117 which is then in the path of the pin 114 rocks the bell-crank plate 106 and this moves the rod 103 to effect the engagement of the clutch. When the control arm is in the position B, the sub-total cycle also operates to engage the clutch, the pin 125 being in engagement with a recess on the cam plate which permits the catch 109 to engage the pin 110 so that movement of the link 100 also moves the rod 103. To cause the paper-feed mechanism to operate at each operation of the machine, the control arm is moved to A when a pin 129 moves an arm 127 which is in contact with a pin 130 on the link 113. Raising the link 113 moves the rod 103 to engage the clutch as before and in this position of the control arm the clutch is never disengaged. According to the Provisional Specification, the long-paper-feed mechanism may be applied direct to the platen, and Specification 328,282, [Class 100 (iv)], is referred to.