Combined service and parking brake

Claim 2

A disk brake assembly comprising a housing defining a bore, a piston slidably supported within said bore, said bore being adapted to be exposed to fluid pressure for actuating said piston to bring an associated brake pad into frictional engagement with a rotor, spring means nested within said piston, said spring means having an operative connection with said piston and said housing for exerting an actuating force upon said piston, and release means for relieving said piston from the actuating force of said spring means for normal fluid pressure operation of said brake assembly.

Claim 3

A disk brake assembly as set forth in claim 1, wherein the operative connection between the spring means and the piston includes automatic adjusting means for adjusting the at rest position of said piston.

Claim 4

A disk brake assembly as set forth in claim 2, wherein the automatic adjusting means includes a threaded connection, the operative connection between the spring means and the piston including an adjusting member having a lost motion connection with said piston.

Claim 5

A disk brake assembly as set forth in claim 1, wherein the release means comprises a fluid operated piston.

Claim 6

A disk brake assembly as set forth in claim 4, wherein the fluid operated piston of the release means is supported within a second bore in the housing concentric and spaced from the first bore.

Claim 7

A disk brake assembly including a rotor having a braking surface, a brake pad juxtaposed to said rotor and adapted to frictionally engage said rotor braking surface, a caliper defining a cylindrical bore, a piston slidably supported in said cylindrical bore and adapted to operate said braking pad for bringing said brake pad into frictional engagement with said rotor braking surface, an adjusting member operatively associated with said piston and having a threaded portion, a threaded member matingly engaged with said threaded portion of said adjusting member, a spring means interposed between said caliper and said threaded member for urging said threaded member, said adjusting member and said piston to a brake pad applying position, an auxiliary piston affixed to said threaded member, means for applying fluid pressure to said auxiliary piston for moving said threaded member and compressing said spring means for precluding spring application of said brake pad, and means for manually relieving the force applied by said spring means to said piston for preventing spring actuation of the brake pad.

Claim 8

A disk brake assembly including a rotor having a braking surface, a brake pad juxtaposed to said rotor and adapted to frictionally engage said rotor braking surface, a caliper defining a cylindrical bore, a piston slidably supported in said cylindrical bore and adapted to operate said braking pad for bringing said brake pad into frictional engagement with said rotor braking surface, an adjusting member operatively associated with said piston and having a threaded portion, a threaded member matingly engaged with said threaded portion of said adjusting member, a spring means interposed between said caliper and said threaded member for urging said threaded member, said adjusting member and said piston to a brake pad applying position, an auxiliary piston affixed to said threaded member, means for applying fluid pressure to said auxiliary piston for moving said threaded member and compressing said spring means for precluding spring application of said brake pad, and means for manually relieving the force applied by said spring means to said piston for preventing spring actuation of the brake pad.

Claim 9

A disk brake assembly as set forth in claim 6 wherein the means for manually relieving the force exerted by the spring means includes a threaded member engageable with an abutment.

Claim 10

A disk brake assembly as set forth in claim 6 wherein the means for manually relieving the force of the spring means includes means for exerting an axial force on the threaded member in opposition to the force exerted thereupon by the spring means.

Claim 11

A disk brake assembly as set forth in claim 6 further including manually operable release means for relieving the force exerted by the spring means upon the piston.

Claim 12

A disk brake assembly as set forth in claim 6 wherein the spring means comprise a plurality of Belleville springs.

Claim 13

A disk brake assembly as set forth in claim 10 wherein the automatic adjusting means includes a female threaded member extending from the first bore to the second bore, the fluid operated piston of the release means being connected to said female threaded member and the Belleville spring means encircling said female threaded member.

Claim 14

A disk brake assembly for providing hydraulic and automatic spring operation of a brake pad comprising a first fluid motor having a first piston operatively associated with the brake pad for actuating the brake pad, spring means operatively associated with the brake pad for automatically applying the brake pad, a second fluid motor having a second fluid piston operatively associated with said spring means for relieving the actuating force exerted by the spring means on the brake pad in response to the application of fluid pressure thereto, and means for manually relieving the pressure exerted by the spring means on the brake pad for releasing the brake pad manually upon failure of the second fluid motor.

Claim 15

A disk brake assembly for providing hydraulic and automatic spring operation of a brake pad comprising a first fluid motor having a first piston operatively associated with the brake pad for actuating the brake pad, spring means operatively associated with the brake pad for automatically applying the brake pad, a second fluid motor having a second fluid piston operatively associated with said spring means for relieving the actuating force exerted by the spring means on the brake pad in response to the application of fluid pressure thereto, and means for manually relieving the pressure exerted by the spring means on the brake pad for releasing the brake pad manually upon failure of the second fluid motor.