Control system for a hydraulic clamping device Patent #: 3980000
ApplicationNo. 690136 filed on 05/26/1976
US Classes:137/596.2, Biased closed91/445, Stop valve between working chamber and inlet and exhaust valve91/447Between working chamber and inlet and exhaust valve
ExaminersPrimary: Cohen, Irwin C.
Attorney, Agent or Firm
International ClassesF15B 011/08
AbstractA cylinder locking apparatus primarily intended for use on counter-balanced lift trucks incorporating lift cylinders of the single-acting type, comprising a positive sealing poppet-type check valve which operates in the normal manner when the system is in the raise mode, but which in the lowering mode is operable by controlled pilot means triggered manually by the system's main control valve spool, thus permitting the load to be lowered by gravity.