(57) The spool-type load check valve (20) of this invention, used in conjunction with
additional check valves (60, 61) overcomes the problem of leakage in conventional
spool type check valves by providing a series of interconnecting passages and chambers
(36) for communicating equalized fluid pressure from a cylinder (11) to either end
of the spool (27) thereof to provide for minimal leakage. When a pair of such cylinders
(11, 12) are utilized, the load check valves (20, 20') associated therewith are interconnected
by a balance line (50) and resolver valves (47') ensure equalization of fluid pressure
in the cylinders upon actuation thereof and also a gradual descent of a load carried
by the cylinders upon loss of fluid pressure between the check valves.
|
|
