Transmission with fluid pressure released brake

Claim 2

In a transmission parking brake mechanism for a vehicle, a brake disengaging system comprising a rotatable toothed member drive-connected to the vehicle wheels, a locking pawl movable into and out of an engaged position relative to said rotatable toothed member, contact means for pivotally contacting said locking pawl for maintaining said locking pawl in engagement with said rotatable toothed member, a stepped linkage member reciprocally mounted adjacent said contact means, spring means for urging said contact means into contact with both said locking pawl and said stepped linkage member, cable means operatively connected to said stepped linkage member, a sheath mounted around said cable means and fixed at one end thereof, selector means for manually reciprocally moving said cable means through said sheath, valve means secured to the free end of said sheath, piston means operatively connected to said valve means and to said stepped linkage member for moving said stepped linkage member so as to cause the larger stepped portion thereof to move said contact means out of contact with said locking pawl in response To the reaction of said sheath to movement of said cable means therethrough when said locking pawl and said contact means are tightly engaged due to vehicle loads tending to lock up said locking pawl and said rotatable toothed member.

Claim 3

In a transmission parking brake mechanism for a vehicle, including a rotatable member drive-connected to the vehicle wheels, a toothed locking member formed on said rotatable member, and a toothed locking element pivotable into and out of an engaged position relative to said toothed locking member, a brake disengaging system comprising spring-biased lever means for contacting said toothed locking element for maintaining said toothed locking element in engagement with said toothed locking member, variable diameter rod means reciprocally mounted adjacent said lever means, cable means operatively connected to said variable diameter rod means, a sheath mounted around said cable means and fixed at one end thereof, selector means for manually reciprocally moving said cable means through said sheath and said variable diameter rod means past said lever means, valve means secured to the free end of said sheath, piston means operatively connected to said valve means and to said variable diameter rod means for moving said variable diameter rod means so as to cause a larger diameter portion thereof to move said lever means out of contact with said toothed locking element in response to the reaction of said sheath to movement of said cable means therethrough under load conditions.

Claim 4

In a transmission parking brake mechanism for a vehicle, including a rotatable member drive-connected to the vehicle wheels, a toothed locking member formed on said rotatable member, and a toothed locking element pivotable into and out of an engaged position relative to said toothed locking member, a brake disengaging system comprising spring-biased lever means for contacting said toothed locking element for maintaining said toothed locking element in engagement with said toothed locking member, variable diameter rod means reciprocally mounted adjacent said lever means, cable means operatively connected to said variable diameter rod means, a sheath mounted around said cable means and fixed at one end thereof, selector means for manually reciprocally moving said cable means through said sheath and said variable diameter rod means past said lever means, valve means secured to the free end of said sheath, piston means operatively connected to said valve means and to said variable diameter rod means for moving said variable diameter rod means so as to cause a larger diameter portion thereof to move said lever means out of contact with said toothed locking element in response to the reaction of said sheath to movement of said cable means therethrough under load conditions.

Claim 5

In a transmission parking brake mechanism for a vehicle, a brake disengaging system comprising a rotatable member drive-connected to the vehicle wheels, a toothed locking member formed on said rotatable member, a toothed locking element pivotable into and out of an engaged position relative to said toothed locking member, lever means for pivotally engaging said toothed locking element for maintaining said toothed locking element in engagement with said toothed locking member, two-diameter rod means reciprocally mounted adjacent said lever means, spring means for urging said lever means into contact with both said toothed locking element and said two-diameter rod means, cable means operatively connected to said two-diameter rod means, a sheath mounted around said cable means and fixed at one end thereof, selector means for manually reciprocally moving said cable means through said sheath, valve means secured to the free end of said sheath, piston means operatively connected to said valve means and to said two-diameter rod means for moving said two-diameter rod means so as to cause the larger diameter thereof to move said lever means out of contact with said toothed locking element in response to the reaction of said sheath to movement of said cable means therethrough.

Claim 6

In a transmission parking brake mechanism for a vehicle, a brake disengaging system comprising a rotatable member drive-connected to the vehicle wheels, a toothed locking member formed on said rotatable member, a toothed locking element pivotable into and out of an engaged position relative to said toothed locking member, lever means for pivotally engaging said toothed locking element for maintaining said toothed locking element in engagement with said toothed locking member, two-diameter rod means reciprocally mounted adjacent said lever means, spring means for urging said lever means into contact with both said toothed locking element and said two-diameter rod means, cable means operatively connected to said two-diameter rod means, a sheath mounted around said cable means and fixed at one end thereof, selector means for manually reciprocally moving said cable means through said sheath, valve means secured to the free end of said sheath, piston means operatively connected to said valve means and to said two-diameter rod means for moving said two-diameter rod means so as to cause the larger diameter thereof to move said lever means out of contact with said toothed locking element in response to the reaction of said sheath to movement of said cable means therethrough.

Claim 7

In a transmission parking brake mechanism for a vehicle, a brake disengaging system comprising a rotatable member drive-connected to the vehicle wheels, a toothed locking member formed on said rotatable member, a toothed pawl member pivotable into and out of an engaged position relative to said toothed locking member, first spring means for urging said toothed pawl member out of contact with said toothed locking member, a pivotally mounted lever having a contoured surface formed thereon, a roller rotatably mounted on said lever for rotatably contacting said toothed pawl member for maintaining said toothed pawl member in engagement with said toothed locking member, linkage means including a small diameter portion, a larger diameter portion, and a frusto-conical portion intermediate said small and larger diameter portions, said linkage means being reciprocally mounted adjacent said contoured surface of said lever, second spring means for pivotally urging said contoured surface of said lever into contact with said linkage means and said roller into contact with said toothed pawl member, a cable, a sheath mounted around said cable and fixed at one end thereof, said cable being reciprocally slidably movabLe within said sheath, selector means operatively connected to one end of said cable for manually reciprocally moving said cable through said sheath, valve means secured to the free end of said sheath, a rod member secured to the other end of said cable and having a shoulder formed thereon, said shoulder being slidably mounted within said valve means, said rod member being operatively connected to the small diameter portion of said linkage means, piston means operatively connected to said valve means and slidably mounted on said rod member for contacting said shoulder so as to cause said frusto-conical portion and said larger diameter portion of said linkage means to pivot said lever out of contact with said toothed pawl member in response to the reaction of said sheath to movement of said cable therethrough against the force of said second spring means, thereby permitting said first spring means to pull said toothed pawl member out of contact with said toothed locking member.

Claim 8

In a transmission parking brake mechanism for a vehicle, a brake disengaging system comprising a rotatable member drive-connected to the vehicle wheels, a toothed locking member formed on said rotatable member, a toothed pawl member pivotable into and out of an engaged position relative to said toothed locking member, first spring means for urging said toothed pawl member out of contact with said toothed locking member, a pivotally mounted lever having a contoured surface formed thereon, a roller rotatably mounted on said lever for rotatably contacting said toothed pawl member for maintaining said toothed pawl member in engagement with said toothed locking member, linkage means including a small diameter portion, a larger diameter portion, and a frusto-conical portion intermediate said small and larger diameter portions, said linkage means being reciprocally mounted adjacent said contoured surface of said lever, second spring means for pivotally urging said contoured surface of said lever into contact with said linkage means and said roller into contact with said toothed pawl member, a cable, a sheath mounted around said cable and fixed at one end thereof, said cable being reciprocally slidably movabLe within said sheath, selector means operatively connected to one end of said cable for manually reciprocally moving said cable through said sheath, valve means secured to the free end of said sheath, a rod member secured to the other end of said cable and having a shoulder formed thereon, said shoulder being slidably mounted within said valve means, said rod member being operatively connected to the small diameter portion of said linkage means, piston means operatively connected to said valve means and slidably mounted on said rod member for contacting said shoulder so as to cause said frusto-conical portion and said larger diameter portion of said linkage means to pivot said lever out of contact with said toothed pawl member in response to the reaction of said sheath to movement of said cable therethrough against the force of said second spring means, thereby permitting said first spring means to pull said toothed pawl member out of contact with said toothed locking member.

Claim 9

In a transmission parking brake mechanism for a vehicle, a brake disengaging system comprising a rotatable member drive-connected to the vehicle wheels, a locking gear secured to said rotatable member, a pawl having a tooth-shaped free end pivotable into and out of engagement with said locking gear, a first spring for urging said tooth-shaped free end out of contact with said locking gear, a pivotally mounted lever having a cam surface formed thereon, a roller rotatably mounted on said lever for rotatably contacting said pawl for maintaining said tooth-shaped free end in engagement with said locking gear, a linkage rod including a small diameter portion, a larger diameter portion, and a frusto-conical portion intermediate said small and larger diameter portions, said linkage rod being reciprocally mounted adjacent said cam surface of said lever, a second spring for pivotally urging said cam surface of said lever into contact with said linkage rod and said roller into contact with said pawl, a flexible cable, a sheath mounted around said flexible cable and fixed at one end thereof, said flexible cable being reciprocally slidably movable within said sheath, a pivotable rack secured to one end of said flexible cable, a plurality of differently contoured lever surfaces slidably mounted adjacent said pivotable rack, a plurality of drive ratio selector push-buttons respectively connected to said plurality of lever surfaces for contacting said rack one at a time to pivot said rack to reciprocally move said flexible cable through said sheath, a valve body secured to the free end of said sheath, a solid rod member secured to the other end of said flexible cable and having a shoulder formed thereon, said shoulder being slidably mounted within said valve body, said solid rod member being pivotally connected to the small diameter portion of said linkage rod, a valve sleeve fixed around said valve body, a conduitry system formed on said valve sleeve and valve body, a source of fluid under pressure for said conduitry system, piston means operatively connected to said valve sleeve and valve body and slidably mounted on said solid rod member for contacting said shoulder in response to said fluid under pressure from said conduitry system resulting from the reaction of said sheath to manual movement of said flexible cable therethrough so as to cause said frusto-conical portion and said larger diameter portion of said linkage rod to pivot said lever out of contact with said pawl against the force of said second spring, thereby permitting said first spring to pull said tooth-shaped free end of said pawl out of contact with said locking gear.

Claim 10

In a transmission parking brake mechanism for a vehicle, a brake disengaging system comprising a rotatable member drive-connected to the vehicle wheels, a locking gear secured to said rotatable member, a pawl having a tooth-shaped free end pivotable into and out of engagement with said locking gear, a first spring for urging said tooth-shaped free end out of contact with said locking gear, a pivotally mounted lever having a cam surface formed thereon, a roller rotatably mounted on said lever for rotatably contacting said pawl for maintaining said tooth-shaped free end in engagement with said locking gear, a linkage rod including a small diameter portion, a larger diameter portion, and a frusto-conical portion intermediate said small and larger diameter portions, said linkage rod being reciprocally mounted adjacent said cam surface of said lever, a second spring for pivotally urging said cam surface of said lever into contact with said linkage rod and said roller into contact with said pawl, a flexible cable, a sheath mounted around said flexible cable and fixed at one end thereof, said flexible cable being reciprocally slidably movable within said sheath, a pivotable rack secured to one end of said flexible cable, a plurality of differently contoured lever surfaces slidably mounted adjacent said pivotable rack, a plurality of drive ratio selector push-buttons respectively connected to said plurality of lever surfaces for contacting said rack one at a time to pivot said rack to reciprocally move said flexible cable through said sheath, a valve body secured to the free end of said sheath, a solid rod member secured to the other end of said flexible cable and having a shoulder formed thereon, said shoulder being slidably mounted within said valve body, said solid rod member being pivotally connected to the small diameter portion of said linkage rod, a valve sleeve fixed around said valve body, a conduitry system formed on said valve sleeve and valve body, a source of fluid under pressure for said conduitry system, piston means operatively connected to said valve sleeve and valve body and slidably mounted on said solid rod member for contacting said shoulder in response to said fluid under pressure from said conduitry system resulting from the reaction of said sheath to manual movement of said flexible cable therethrough so as to cause said frusto-conical portion and said larger diameter portion of said linkage rod to pivot said lever out of contact with said pawl against the force of said second spring, thereby permitting said first spring to pull said tooth-shaped free end of said pawl out of contact with said locking gear.