GB557941A - Improvements in or relating to step-by-step controlling mechanisms - Google Patents

Abstract

557,941. Controllers. WYCLIFFE FOUNDRY CO., Ltd., and BARRETT, G. June 9. 1942. No. 7879. [Class 38 (iii)] [Also in Group XXIV] Consists in a step-by-step controlling mec'hanism applicable, for example, to the changing from one set of gear wheels to another or to moving an arm from one electrical contact to another. As applied to the moving of a pinion 1 to a series of predetermined positions along a shaft 2, a slider 3, 4 engages the pinion and is mounted on a shaft 5 parallel with the shaft 2, Slidably mounted in guides 6, 6a is a selector bar 7 having a series of holes 8a ... 8g corresponding in number and pitch with the positions to which the slider is to be moved. The bar 7 has a pin 15 engaging a slot in a disc 14 integral with a spring-loaded plunger 11 provided with an actuating handle 10. A pin 9 on the slider is adapted to enter one or other of the holes in the bar 7 when the latter is thrust towards the slider, e.g. by pressing on the handle 10 or a knob 21. The bar is held parallel to the shaft 5 and disconnected from the slider when pressure is relieved by spring-loaded plungers 17, 17a. The movement of handle 10 is limited by an extension 22, thereon engaging stops 25, 25a, Fig. 3, in a gate 23, which has spaced gaps 24, 24a, and a lip 26. When the extension 22 is below the lip the bar 7 engages the pin 9 and when above the lip the bar and pin are disengaged. The actuation is therefore a downward movement of extension 22 through one of the gaps 24, 24a. Then a rotary movement of handle 10 to move the slider and finally an upward movement of extension 22 through the other gap to free the slider from the bar. The movement of the slider may be rectilinear or angular and the spacing of the holes equal or unequal. Specification 529,506, [Group XXIV], is referred to.