| 摘要 |
<p>An adjustor to compensate for thermal expansion between a valve stem and its operation means within an internal combustion engine. The adjustor comprises a valve spring retainer member (60; Fig 3) having at one end a valve stem receipt aperture (76; 101), said valve spring retainer member (60; Fig 3) being removably retained upon said valve stem by a keeper key. A cap member (66; 191) is located to the other end of said valve spring retainer member (60; Fig 3) and is longitudinally adjustable in position with respect thereto. Hydraulically operable restoration permitting means (78,84; 100, 102, 104, 106, 108, 110, 112) are provided to permit either (a) the restoration of a first longitudinal positional relationship between said cap member (66; 191) and said operation means and, as a result, corresponding restoration in an opposite direction of a second longitudinal positional relationship between said cap member (66; 191) and said valve stem, or (b) the restoration of said second longitudinal positional relationship and, as a result, corresponding restoration in an opposite direction of said first longitudinal positional relationship. The said adjustment means (78,84; 100,102,104,106,108, 110, 112) includes means (80,81,90; 96; 106,108) to vary the longitudinal distance between said cap member (66; 191) and said valve spring retainer member (60; Fig 3), said cap member (66; 191) being arranged neither to be directly attached to said valve stem in normal operation nor to have direct contact with said valve stem.</p> |
