GB597454A - Means for controlling associated machines - Google Patents

Abstract

597,454. Cam actuation of switches. MACHINERY (BIRMINGHAM), Ltd., and HOOSON, G. C. Aug. 20, 1945, No. 21223. [Class 38(v)] [Also in Group XXIX] A master control device for preventing the starting of any but a selected one of a number of machines e.g. riveting presses, each having its own controlling means comprises a manually operable selector lever, agate for determining the positions to which the lever can be moved and means operable by the selector lever for over-riding the controlling means associated with the individual machines. The selector lever m moves in a gate n having a longitudinal slot o and three branch slots p and is mounted on an angulary and axially movable shaft j carrying three cams k which in the selective positions of the lever are located opposite bell crank levers f pivotally mounted on a shaft g. The levers f are loaded by springs i and act either directly or through adjustable abutments h to hold plunger valve e closed against the fluid pressure in a common supply pipe b. Individual valves are permitted to open when a cam k depresses the respective lever f on raising the lever m in the corresponding slot p. Pressure fluid may then pass through an outlet d to the controlling means of the selected machine. Meanwhile the fluid pressure is cut off from the controlling means of the other machines by the remaining valves e. Each lever f may open a spring-loaded electric switch w when in its valve closing position. Where the individual machine controlling means comprise electromagnetically-operated valves, the switches controlling these valves may be in circuit with the switches w which therefore provide an additional safeguard against undesired starting. Each valveoutlet passage c has an adjustable spring- loaded relief valve q. In the case of electrically-operated machines the levers are adapted to actuate switches instead of valves.