GB1056102A - Improvements in or relating to apparatus for rotating a shaft in angular increments - Google Patents

Abstract

1,056,102. Ratchet gearing. WESTERN ELECTRIC CO. Inc. July 9, 1963 [July 11, 1962], No. 27067/63. Heading F2Q. [Also in Division G4] In electromagnetically-operated ratchet gearing for resetting a coin telephone totalizer shaft 31 to its initial position after it has been turned by a coin-actuated arm (not shown), a rachetwheel 37 on the shaft 31 is engaged by a driving pawl 28 and arresting pawl 29 integrally formed on a rocking member 27 pivoted on a pin 22 which is moved up and down a fixed slot 30 by a forked link 20. The link 20 is pivoted to an extension 18 of the electromagnet armature 13 which is pivoted at 14, spring-loaded at 17, and actuates self-interrupting contacts 15. The link 20 is thus reciprocated to rotate shaft 31 until it reaches its initial position, when the current to electromagnet 11 is cut off by means not shown. A C-shaped snap-over spring 26, Fig. 2, having its ends fixed respectively to the member 27 and to a fixed block 24 biases the member 27 anticlockwise, to engage pawl 29, in the lower (coil-de-energized) position of the member, and clockwise, to engage pawl 28, in the upper position of the member. Each down-stroke of link 20 causes the pawl 28 to rotate the wheel by an increment, overrun being prevented by the pawl 29. The wheel 37 is also located at each increment by a roller detent 40, Fig. 1. The point at which the snap-over of member 27 occurs can be adjusted by inserting the end of spring 23 into a different hole 25 in the block 24, and by adjusting a screw 46 which the member 27 abuts during its descent. The block 24 is secured to a fixed bracket 125 by a screw 50, whereby its position relative to wheel 37 can be adjusted. Further adjustment of the mechanism can be achieved by bending extension 18. The shaft 31 carries cams 32, 36, 43 operating respectively switch contacts for the coin telephone circuitry.