Cylinder locking apparatus
Patent 4088151 Issued on May 9, 1978. Estimated Expiration Date: 
May 9, 1995. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
May 9, 1995. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 3030929 3049101 3068596 3127688 3906840 Control system for a hydraulic clamping device Patent #: 3980000 InventorApplicationNo. 690136 filed on 05/26/1976US Classes:137/596.2, Biased closed91/445, Stop valve between working chamber and inlet and exhaust valve91/447Between working chamber and inlet and exhaust valveExaminersPrimary: Cohen, Irwin C.Attorney, Agent or FirmInternational ClassesF15B 011/08F15B 013/042 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. | |
