Patent GB-213977-A (GB)
Title: Improvements in or relating to driving and controlling mechanism for the counters of tabulating machines and similar apparatus
Filed: 1923-01-10
Abstract: 213,977. British Tabulating Machine Co., Ltd., (Tabulating Machine Co.). Jan. 10, 1923. Statistical machines are provided with a friction drive from the main shaft to the counterwheels, with means normally detaining these wheels against the tendency of the frictionclutches to rotate them and operable to release any one or more of the counter-wheels at determinate instants in the cycle, and with means for re-engaging these detaining means at other determinate instants; the cards are fed through the machine so that the " 9 " holes pass under the brushes first and the " 1 " holes last. The driving shaft 1 has rigid with it, one for each counterwheel 2<a>, a friction disc 2 engaging with a friction surface pinned to a counter-wheel 2a and to a gear-wheel 3 freely mounted on the shaft 1 and meshing with a wheel 4 loose on the shaft 5 and having a pin 6 in the path of a pin 7 on a ratchetwheel 8 also loosely mounted on the shaft 5 and fast with a second ratchet-wheel 9, the teeth of these two wheels facing oppositely. Pawls 10, 11 carried by an arm 21 engage with the wheels 9, 8 respectively, and a shaft 12 carries three cams 13, 14, 15. The cam 13 co-operates with a bell-crank 16 carrying a bail 17 adapted to depress latch levers 18, the cam 14 co-operates with an arm 19 having a bail 20 engaging the levers 21 and cam 15 co-operates with a lever 22 fast on the shaft 23 together with an overthrowpreventing pawl 24 for the ratchet-wheel 9. Normally each wheel 9 is held by its pawl 10 but when a card passes through the machine, having, say, the three hole punched in the tens column, then when this hole passes under the brush a current is set up which energizes a countermagnet to swing an arm 25 to engage an extension 26 on the tens pawl 10 so that the latter is disengaged from its wheel 9 and is locked by the latch lever 18 pressed upwards by a spring. This permits the ratchet-wheel to turn, this release being effected at such a moment in the cycle that when the corresponding tens counter-wheel has travelled three number spaces the lever 16 reaches the high part of the cam 13 and thereby depresses the bail 17 to release the latch 18 from the extension 26 so that the pawl 10 re-engages its wheel 9. Transfer-mechanism.-At the commencement of the cycle and before the index points on a card come under the brushes the bail 20 is lowered by the cam 14, allowing the levers 21 to be lowered by springs 27 so that they engage latch levers 28, each adapted to be operated by transfer teeth 29 on the wheel 8 of the adjacent lower denomination during that part of the cycle when the counter-wheel of next lower denomination is going from 9 to 0. When a wheel 8 passes from the 9 to the 0 position, a tooth 29 on it rocks its lever 28 clockwise and releases the lever 21 carrying the pawl 10 of the next higher denomination so that this lever 21 is lowered further until it rests on the bail 20. Near the end of the cycle the bail 20 is lowered further by the portion 14a of the cam 14, the consequent lowering of the lever 21 causing the pawl 10 to contact with a bail 30 and to be thus disengaged from its wheel 9, and at the same time the pawl 11 advances the wheel 8 one tooth, thus effecting the transfer. Overthrow during transfer is prevented by a pawl 24, operated by the cam 15 just after the tip of the tooth 9<a> on wheel 9 has passed the tip of the pawl 24. Zeroizing-mechanism.-To zeroize, the shaft 5 is rotated anticlockwise by a handle 31, the shaft 1 being stationary, and at the commencement a cam 32 rigid with the shaft 5 lifts a lever 33 upwards so that the bail 30 is moved upwards to disengage all the pawls 10 from the wheels 9, the wheels 8, 9 being thereafter picked up and rotated to zero by means of collars 37 rigid on the shaft 5 and pawls 36 on the ratchet-wheels 8. At the very end of the rotation of the shaft 5 the cam 32 allows the arm 33 and bail 30 to be lowered, the pawls 10 thereupon re-engaging the wheels 9. During this rotation of the shaft 5 the gear wheels 3, 4 and counter-wheels 2<a> are held stationary by the shaft 1, so that the pins 7 on the wheels 8 will move away from the pins 6 on the wheels 4. After the rotation of the shaft 5 is completed the shaft 1 is rotated twice clockwise thus rotating the gear wheels 4 until each pin 6 overtakes its corresponding pin 7, and thereafter the wheel 4 is held and the corresponding friction clutch slips, this leaving the counter-wheels at zero. Specification 213,976 is referred to.