HYDROSYSTEM OF INJECTION UNIT AND SET OF DOSE OF INJECTION-MOULDING MACHINE, FOR INSTANCE THERMOPLAST-AUTOMAT Russian patent published in 2010 - IPC B29C45/82 

FIELD: machine building.

SUBSTANCE: hydrosystem contains power supply, connected to hydraulic actuator of dose set of by electrically controlled three-condition main hydraulic control valve. Hydraulic control valve is connected by means of back pressure valve and installed parallel with it controlled gate valve with working cavity of hydraulic actuator of screw displacement. Working cavity of hydraulic actuator is intercommunicated in the mode of decompression through controlled gate valve, and at dose set through back pressure valve, with main route of discharge, three-condition auxiliary hydraulic control valve. Discharge main route is connected to cavity of withdrawal of hydraulic actuator piston for screw displacement, in mode of decompression connected it to the power supply. Controlled gate valve is implemented in the form of double-stage controlled back pressure valve with spring-actuated cavity of control. Spring-actuated cavity of control is connected to working cavity of hydraulic actuator of dose set. Hydrosystem contains power supply, connected to hydraulic actuator of dose set by three-condition main hydraulic valve. Main hydraulic valve is connected to working cavity of hydraulic actuator of screw displacement. Working cavity of hydraulic actuator is connected in the mode of decompression by means of controlled gate valve, and in the mode of dose set through parallel installed to it back pressure valve, with discharge main route. Three-position auxiliary hydraulic valve is connected to cavity of discharge of piston of hydraulic actuator for screw displacement, in the mode of decompression connecting it to the power supply. Three-position main hydraulic valve is implemented as hydrocontrolled with controlling, valve spindle of one with it diagram. Exhaust fluid-power circuit of three-position main hydraulic valve is connected to back pressure valve and controlled gate valve. Controlled gate valve is implemented in the form of double-stage controlled back valve with spring-actuated cavity of control. Spring-actuated cavity of control is connected to one of cavities of control of three-position main hydraulic valve.

EFFECT: increasing of field-performance data of device.

2 cl, 4 dwg