Hydraulic press control system - has valves shut by control pressure in ram feed and discharge pipes

摘要

The hydraulic control cycle is for machines such as presses, shears etc, having a vertical tappet whose stopping and also its closing and opening movement is regulated by a 4/3 -way valve, while on the discharge side of the fluid there is a valve controlled by the latter, between the ram piston rod and the 4/3 -way valve. A valve (5, 7), shut by a control pressure, is mounted both in the feed (4) and discharge (6) pipes of the ram (1), this pressure being derived from below the rod side of the ram piston (2). A single valve (9) in a common part (10) of the control piping (10a, 10b) to each of these valves (5, 7) or alternatively there is a separate valve in the pipe to each. This is shut simultaneously with actuation of the 4/3-way valve.