Patent GB-703968-A (GB)
Title: Calculating or similar accounting machines
IPC: G06C21/02
Filed: 1952-04-02
Abstract: 703,968. Calculating-apparatus. NATIONAL CASH REGISTER CO. April 2, 1952 [June 27, 1951], No. 8405/52. Class 106 (1) In a machine having mechanism effecting automatic release in predetermined columnar positions of a travelling record material carriage, but not if a selected add/subtract totalizer is overdrawn, additional mechanism is provided which effects release in certain of said columnar positions regardless of the condition of the totalizer. In the mechanism shown, column stops 21, 22 on the carriage bar 17 are fitted with pins 23 or 24 where automatic release is required, and larger diameter pins as 24 are employed if release is not to be conditional upon the totalizer registering a positive total. The carriage is released for tabular movement by counterclockwise movement of a control lever 74 to engage a lower step 76 therein with a fixed stud 75, a spring_ urging the lever downwardly and to the right. Carriage movement ceases when a column stop 21 or 22 meets an abutment arm 203 connected with the lever 74, and restores the lever with an upper step 77 engaging the stud 75. This leftward restoring movement of the lever 74 is communicated to a lever 26, mounted by means of a slot 28 on a stud 27, if the column stop is fitted with a pin 23 or 24 which rocks the lever 26 counterclockwise to engage a hook 72 thereon with a shoulder 73 on the lever 74, and the lever 26, through a lever 32, raises a link 36 (see also Fig. 2) to release the machine for cyclic operation. To prevent release if the totalizer is negative, the link 36 is rocked clear of the lever 32 early in each cycle by means of a slide 84 operated against a spring 92 by a follower 88 of a cam 91 on the main shaft 54. An overdraft shaft 98 (see also Fig. 3) is then rocked clockwise and back to raise and lower a sensing finger 105 for the highest order totalizer wheel 99, and to raise and lower an obstructing finger 94 for a pin 93 on the slide 84. If the totalizer is or becomes overdrawn, a tooth 104 on the wheel 99 obstructs return of the sensing finger 105 and overdraft shaft 98 so that the finger 94 prevents return of the slide 84. The link 36 consequently remains clear of the lever 32 and operation thereof by a column stop is ineffective to release the machine, so warning the operator of the condition of the totalizer. The invention provides a slide 134 pin-and-slot mounted on the lever 32, and connected with the lever 26 by means of a bell-crank 131 so that rocking of the lever 26 by a pin 23 or 24 moves the slide towards the link 36. In the case of a larger diameter pin 24, the additional movement is sufficient to bring the slide 134 into the plane of link 36 and its location behind (Fig. 1) the lever 32 enables it to lift the link even though the link is held clear of the lever 32 owing to the totalizer being overdrawn. The machine is therefore released regardless of the condition of the totalizer. Machine release.-The lifted link 36 (Fig. 2) rocks a latch lever 38 to release a slide 41 to a spring 50, the slide rocking the tripping arm 51 of a one-revolution clutch. The tripped arm 51 releases a clutch control arm 52 loose on the main cam shaft 54, and a spring 59 rocks the control arm 52 clockwise relatively to a driven disc 55 of the clutch fast on the shaft 54. A dog 57, mounted to rotate in the disc 55 and having toothed engagement with the arm 52, is thereby rocked to engage the notched periphery of a driving disc so clutching the shaft 54 to the driving disc for one revolution, whereupon the restored arm 51 blocks the control arm 52 and the drive is interrupted by the dog 57 being returned to present a clearance flat 60 to the driving disc.