Device for moving hydraulic pistons arranged in hydraulic cylinder in calender of e.g. paper-making machine, has parallel circuit valve e.g. solenoid Valve, arranged between digital hydraulic pressure control valves and hydraulic cylinders

摘要

The device has chambers (A, B, A', B') formed in a hydraulic cylinder (13, 13'). The chambers are impinged by hydraulic pressure produced by hydraulic fluid e.g. hydraulic oil, over hydraulic lines guiding a digital hydraulic pressure control valves (15, 15'). The digital hydraulic pressure control valves comprise series parallel circuit valves, supply lines and a removing line (23). A parallel circuit valve e.g. solenoid Valve, is arranged between the digital hydraulic pressure control valves and the hydraulic cylinders. Independent claims are also included for the following: (1) a device for changing position of a mass (2) a method for movement of mass by moving pistons (3) a method for checking function of a pressure accumulator.