Vehicle transmission hill holder
AssigneeFord Motor Company
InventorAlvin H. Berger
Life of this patent
Estimating the term…
Abstract
A hill hold mechanism for use in a motor vehicle transmission. The mechanism includes a one-way clutch coupled to a transmission input shaft, a toggle link with a friction pad coupled to the transmission output shaft, and a friction band, coupled to the one-way clutch, for locking the one-way clutch when the toggle link and the friction pad react to a change in rotational direction of the output shaft. With this mechanism, when a vehicle is stopped on an incline and the vehicle attempts to roll down the incline, the one-way clutch is engaged and prevents rolling, but will not prevent the vehicle from moving in the driven direction when the vehicle engine begins to power it.
Claims19
A vehicle transmission comprising:
- a housing having a gear train enclosed therein;
- an input shaft protruding into the housing and coupled to the gear train for driving the gear train;
- an output shaft protruding out of the housing and reversibly coupled to the input shaft through the gear train with the output shaft driven by the gear train;
- disengageable clutch means, attached to the input shaft and operatively engaging the housing, for permitting rotation of the input shaft in only one direction when engaged, and in both directions when disengaged;
- actuating means, coupled to the output shaft, for sensing a change in rotational direction of the output shaft;
- and
- locking means, operatively responsive to the actuating means, for selectively engaging the clutch means when the actuating means senses a change in rotational direction of the output shaft.
A vehicle transmission comprising:
- a housing having a gear train enclosed therein;
- an input shaft protruding into the housing and coupled to the gear train for driving the gear train;
- a manual clutch connected to the opposite end of the input shaft from the gear train;
- an output shaft protruding out of the housing and reversibly coupled to the input shaft through the gear train, with the output shaft driven by the gear train;
- a one-way clutch, attached to the input shaft and operatively engaging the housing, having an engaged position such that the clutch will only allow the input shaft to rotate in one direction and a disengaged position such that the input shaft can rotate in either direction;
- sensing means, cooperating with the output shaft, for sensing a change in rotational direction of the output shaft;
- and
- locking means for selectively causing the one-way clutch to be in its engaged position when the sensing means senses a change in rotational direction of the output shaft.
A vehicle transmission having a hill holder mechanism, the transmission including a housing for rotatably supporting an input shaft having a driven direction of rotation and coupled to a vehicle engine, an output shaft coupled to vehicle drive wheels, and a gear train selectively interconnecting the input and output shafts, with the transmission shiftable between a forward and a reverse gear position, the hill hold mechanism comprising:
- a releasable one-way clutch having an inner member rotationally fixed relative to the transmission input shaft and an outer member coupled to the inner member such that the inner member can rotate in only the driven direction relative to the outer member;
- locking means coupled to the outer member and the housing and movable between a locked and an unlocked position for respectively locking and unlocking the one-way clutch such that the locking means prevents rotation of the outer member relative to the housing, causing the one-way clutch to permit rotation of the input shaft only in the driven direction when the locking means is in the locked position and the one-way clutch permits rotation of the input shaft in either direction when the locking means is in the unlocked position;
- and
- friction means, associated with the output shaft, for changing position when the output shaft reverses direction and thereby causing the locking means to move between the locked and the unlocked positions.
Dependencies are inferred from the claim text.