Flow matching valve and hydraulic system employing same
This patent describes a control valve comprising; a generally tubular sleeve; a piston axially slidable within the sleeve, the sleeve and piston having a first pair of mating valving surfaces and, axially spaced from the first pair, a second pair of mating valving surfaces, the valving surfaces being matched to open in synchronism; in the piston, a first passageway from the first valving surface to one end of the piston and a second passageway opening from the second valving surfaces to the other end of the piston; in the sleeve, passageways connecting each set of the valving surfaces to respective drain ports, at one end of the sleeve, a valve seat; a valving member adapted to mate with and close off the seat, the piston including a portion which, during movement of the piston, engages the valving member to lift it off the seat substantially at the same time that the mating valving surfaces open; and in the sleeve, separate from the drain ports, a fill port connecting into the space between the valving member and the piston.
- Assignee:
- Rexa Corp., Dover, MA
- Patent Number(s):
- US 4766728
- OSTI ID:
- 6529093
- Country of Publication:
- United States
- Language:
- English
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