PERFEZIONAMENTO NELLE UNITA DI CON TROLLO PER SISTEMI IDRAULICI

摘要

The hydraulic controller is for controlling the operation of a plurality of hydraulically controlled devices. Hydraulic fluid may be selectively distributed by the controller to various controlled hydraulic devices in a timed and predetermined sequence. The timing of the distribution of hydraulic fluid by the controller can be quickly and easily varied by various control knobs on the controller to thereby vary the timed operated period of the various machine operations controlled by such devices without affecting the timed operation of other machine operations. The controller is supplied with a source of hydraulic fluid under a generally constant pressure. Cam means are associated with each of a plurality of fluid flow distributing valves for operating such associated valve members in a predetermined sequence of valve positions upon advancement of the cam means relative thereto. Drive means including a pair of opposed indexing and timing device pistons; advance the cam means relative to the valves to operate them in sequence of positions and in operating intervals or dwell periods thereof. The indexing piston has an effective working diameter in its cylinder which is greater than that of the timing piston such that it normally overrides the timing piston. The cam drive means includes lost motion means for allowing the cam means and associated distributing valves to dwell during timing strokes. Fluid flow restrictor means adjustably restrict the flow of fluid through the venting means to control the speed of the timing stroke and thereby provide an adjustable timed interval of operation of the device then being operated.