| 摘要 |
<p>A fluid control system (10) for a continuously variable transmission (12) utilizing a first valve (56) which is manually Dperable, and a second valve (66) operable by a fluid motor 160) which fluid motor (60) also provides engagement and disengagement of two gear ratios. The first valve (56) directs fluid flow from a fluid source (46) to the fluid motor (60) and to the second valve (66) for communication to a fluid actuated starting clutch (30). Fluid for the clutch (30) and fluid motor (60) are only provided when the first valve (56) is selectively engaged to the first (37) or second (39) operable gear ratios thereby directing fluid from the fluid source (46) to the fluid actuated motor (60). The fluid motor (60) is operable to move a gear engaging means (35) and simultaneously move the second valve (66) to an aligned port position permitting fluid flow to the starting clutch (30). The clutch (30) is only engaged when the manually operated valve (56) is in the first (26) or second (28) gear ratio position, therefore, independent park and neutral positions have been obviated by the fact that such a starting clutch (30) is no longer providing power to an output means (44, 45). In an alternative embodiment a pressure modulator valve (54) is interposed between the fluid source (46) and the first valve (56) to control the line pressure to the fluid control system (10). The use of the starting clutch (30) in this fashion obviates the use of a forward clutch to provide driving communication between input (14) and output (44, 45) means.</p> |
