Unbalanced hydraulic amplifier valve assembly

US4638719A · kind A · utility

Assignee

• Volkswagenwerk AG · DE

Inventors

• Gunter Leineweber · Gifhorn, DE
• Rolf Warnecke · Ulmen, DE
• Heinz Ruhmer · Wolfenbüttel, DE

Key dates

• Filing date: Oct 30, 1985
• Grant date: Jan 27, 1987
• Expiry date: Oct 30, 2005

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B60T13/12
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

A pressure-unbalanced hydraulic amplifier valve assembly has an axially slidable amplifier piston and a control plunger axially slidably arranged in the amplifier piston with a loose fit to permit a slight radial movement thereof in the amplifier piston. For providing a tight seal in the zone of control ports arranged in the amplifier piston, the control plunger is urged in that zone radially against the amplifier piston by a transverse piston continuously exposed to the system pressure. A pressure piston engages one end of the control plunger and is exposed to an external force (such as a braking force applied by a pedal) for axially displacing the control plunger. In order to eliminate undesired axial force components from the force applied by the transverse piston, a force-transmitting ball contacts the transverse piston and an inner wall of the control plunger forming a throughgoing axial bore and constituting an axially linear track for the ball. In order to eliminate undesired transverse force components from the force exerted by the pressure piston on the control plunger, these two components contact one another by means of mutually transversely arranged pins which are solel…