摘要 |
A valve device consisting of a valve body with a bore slidably receiving a valving plunger (30, 34) and having openings (64, 68) spaced along the bore wall for carrying high pressure controlling or controlled fluid. Interposed between the openings is soft seal means, such as O-rings (48, 54), embedded in suitable recessing in the bore wall. The valve plunger has an internal passage (76) with longitudinally spaced ports or ducts (78, 80) opening through the plunger wall and movable with the plunger, selectively, between positions on the same side of the seal means and on opposite sides thereof for connecting the body openings. The plunger transverse ducts (78, 80) are not of appreciably greater cross-sectional dimensions, longitudinally of the plunger, than said soft seal means (48, 54) and is closely confined on all sides, when exposed to a plunger port, by adjacent body and plunger wall structure so that distortion and extrusion of the seal, under high pressure in the plunger passage, is prevented.
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