| 摘要 |
<p>Bypass valve comprising a ported housing (1) and concentrical ported slee ve (2). Ported piston (3) is slidably arranged within the sleeve. Between sl eeve and piston is a control system consisting of control element (5) fixed to sleeve (2) by means of plugs (7) passing through apertures (49) and holes (68). Noses (35) protrude into recesses (34) of drive element (4). Saw teet h (31) on drive element (4) interact with teeth (29) on rotatable timing ele ment (6). Key (27) on element (6) interacts with teeth (32) on control eleme nt (5). Lower end (70) of key is abutting against ridge (67) formed on inner surface of sleeve (2). when key (27) is engaged to teeth (32), teeth (31, 2 9) on elements (4, 6) are misaligned. Pressure increase results in piston (3 ) and drive element (4) moving downward freeing key (27) from engagement wit h teeth (32). Teeth (31, 29) are forced into alignment with subsequent rotat ion of timing element (6). In this position, ports on piston and sleeve are partially aligned. Pressure decrease results in element (6) moving up key (2 7) moving to next notch of teeth (32). When key (29) coincides with slot (50 ), piston (3) moves further down, partially occluding piston ports. When key (27) coincides wth slot (52) piston (3) moves even further down totally occ luding piston ports.</p> |
