Document Type and Number:
Japanese Patent JPS5214701
Kind Code:
U
Abstract:
A control for a mobile excavating backhoe comprising a handball including a trigger lever mounted for pivotal movement, a plunger operatively associated therewith, internal passages for permitting pressurized air to flow between inlet, exhaust and signal ports, and a metering or modulating valve regulating the air flow between the inlet, exhaust and signal ports. Pivotal movement of the lever is translated into axial movement of the plunger and the metering valve to produce a variable pressure signal at one of the signal ports in the handball. The signal controls an air cylinder in the pneumatic control system, and the cylinder is connected to a hydraulic control valve which provides the necessary oil pressure for operating a double acting hydraulic cylinder secured to the frame of an earth-moving machine. The magnitude of the variable pressure signal determines the extent of movement of the hydraulic control valve, thus providing proportional control over the functions of the earth-moving machine.
Application Number:
JP8887776U
Publication Date:
February 02, 1977
Filing Date:
July 06, 1976
Export Citation:
International Classes:
E02F9/20
Domestic Patent References:
| JPH0717408U | 1995-03-28 | |||
| JPS3525763Y1 |