摘要 |
An improved valve rotator includes a plurality of biasing springs which are effective to urge associated balls toward the shallow ends of ramps formed between a pair of housing members. The total force applied against the balls by the biasing springs is sufficient to hold the housing members apart against the influence of a valve spring when the valve is in a closed position. Upon movement of the valve toward an open position, the valve spring force increases to a magnitude sufficient to cause the balls to move down the associated ramps against the influence of the biasing springs. As the balls move down the ramps, rotational movement of the balls causes one of the housing members to rotate relative to the other with a resulting rotation of the valve as it opens. As the valve subsequently moves toward the closed position, the valve spring force decreases and the ball biasing springs are effective to move the balls up the ramps to separate the two housing members against the influence of the valve spring. The separating movement between the two housing members is in a direction in which the valve is closed so that the separating movement promotes the closing of the valve. To prevent reverse rotation of the valve as it is closed, a one-way clutch arrangement is utilized to inhibit relative rotation between the housing members as they separate and the balls move up the ramps. |