SYSTEM FOR PROTECTION OF CRANK PRESS FROM OVERLOADS Russian patent published in 1998 - IPC

FIELD: mechanical engineering, in particular, designs of units of press-forging machinery. SUBSTANCE: system has hydraulic support installed under connecting rod and communicated via pressure line and check valve to pump and to controlled relief valve including controlled servovalve, pressure regulator installed in pressure line of servovalve, distributing device connected with electric circuit if press control, and controlled two-position, two-way valve installed in pressure line of servovalve for connection of its control with shutoff member of servovalve. Relief valve and servovalve are connected with return line. Pump is made with two with two working media, for instance, of hydropneumatic type. Servovalve is made in the form of diaphragm valve in which shutoff member is engageable via supporting disc with elastic diaphragm. Distributing device in the form of one-sided electric control consists of two-position, three-way distributor with two control pneumatic hollows, one of which is connected with electrically controlled two-position, three-line distributor whose electromagnet is connected to circuit of pump limit switch, while the other, is connected to pneumatic line which connects pressure line of servovalve with pneumatic hollow of hydropneumatic pump. Pressure regulator is connected with two-position, three-way distributor and electrically connected two-position, three-line distributor. EFFECT: higher efficiency. 2 dwg