Abstract A valve to be used in a hydraulic pallet truck comprises a valve housing, the inlet side of which is provided with a valve seat. Axially displaceable to and from this seat is a valve cone and behind the seat, where the cone is, are in the housing formed two different sized chambers axially after each other. The first one has a smaller cross section than the second one and surrounds the valve cone, when that engages the valve seat, forming between them a narrow passage for the pressure medium. The valve cone is movable from the valve seat through the first chamber and into the second chamber. When the operator moves the cone in the first chamber a flow dependent pressure fall will arise over the valve cone, which thereby is subject to a counteracting force in relation to the force which by the operator is exerted on it for its opening.
A valve comprising a housing having an inlet and an outlet and a passage between said inlet and outlet, a valve seat formed on said housing and surrounding said passage, a first cylindrical chamber of relatively small diameter on the inlet side of said valve seat, a second cylindrical chamber of relatively large diameter coaxial with said first chamber and on the inlet side of said first chamber, and a valve member reciprocable in said passage coaxially of said chambers, said valve member comprising a cone that bears against said seat in the closed position of said valve member, a valve stem reciprocable in said housing on the outlet side of said cone, said cone on the inlet side thereof terminating in a cylinder coaxial with and disposed within said first chamber in said closed position, said cylinder having the largest diameter of any portion of the valve member, said cylinder being movable out of said first chamber and entirely into said second chamber upon manipulation of said valve stem.
Claim 2
Dependent Claim
170 words
A valve comprising a housing having an inlet and an outlet and a passage between said inlet and outlet, a valve seat formed on said housing and surrounding said passage, a first cylindrical chamber of relatively small diameter on the inlet side of said valve seat, a second cylindrical chamber of relatively large diameter coaxial with said first chamber and on the inlet side of said first chamber, and a valve member reciprocable in said passage coaxially of said chambers, said valve member comprising a cone that bears against said seat in the closed position of said valve member, a valve stem reciprocable in said housing on the outlet side of said cone, said cone on the inlet side thereof terminating in a cylinder coaxial with and disposed within said first chamber in said closed position, said cylinder having the largest diameter of any portion of the valve member, said cylinder being movable out of said first chamber and entirely into said second chamber upon manipulation of said valve stem.
Claim 3
Dependent Claim
38 words
A valve as claimed in claim 1, and a coil compression spring extending axially of said second chamber and acting between a wall of said second chamber and said cylinder to urge said valve member to closed position.
Claim 4
Dependent Claim
22 words
A valve as claimed in claim 1, the greatest diameter of said cone being substantially equal to the diameter of said cylinder.
Claim 5
Dependent Claim
26 words
A valve as claimed in claim 1, said valve stem sliding in said housing and said outlet being laterally offset from the axis of said chambers.