Abstract:
A band brake assembly comprises a friction element (12) engageable with a rotatable member (10) and an input linkage assembly (30) controlling engagement of the friction element with the rotatable member. The input linkage assembly (30) is carried by a mounting bracket (32) and includes a first lever (34), a bearing assembly (38) and a second lever (40) engageable with an end plate (42) secured to the ends of the friction element (12). The end plate (42) carries pins (22, 24) secured to the friction element and extending into slots (52, 54) on the mounting bracket (32). The pins transfer braking torque to the mounting bracket (32) and are guided by the slots to provide a servo assist during braking.
Abstract:
A proportioning valve assembly (10, 210) in a housing (12, 212) is pressure responsive to control the flow of fluid to a wheel brake cylinder. The proportioning valve (20, 220) is connected to a fluid channel (31, 231) opening into a reservoir (13, 213), a second valve (34, 234) being disposed in the channel (31, 231) and being engaged by an inertia sensitive ball (40, 240) located either on a ramp (17) or within a recess (235) of the second valve (234). The ball (40) is responsive to deceleration of the vehicle and moves up the ramp (17), or the ball (240) moves multi-directionally from the recess (235) to be both longitudinal and lateral deceleration responsive. Movement of the ball (40, 240) permits the second valve (34, 234) to close and prevent fluid communication between the fluid reservoir (13, 213) and the proportioning valve (20, 220) in order to vary the outlet pressure of the proportioning valve (20, 220) in response to deceleration or cornering of the vehicle. The proportioning valve (20, 220) includes a second piston (80, 280) which has a plunger end (82, 282) that extends within the channel (31, 231) and a bore (303) of a sleeve (301). The sleeve (301) has an orifice (307) to restrict fluid pressure flow from the bore (303) around the plunger end (282) and through the orifice (107, 307) to the channel (31, 231). The sleeve (301), orifice (307), and plunger end (82, 282) provide damping of second piston when sudden high pressure applications occur, and thereby eliminate the occurrence of wheel lock-up.
Abstract:
The universal joint (10) comprises a first shaft (12) with an annular head (14) having a cavity (16) therein and oppositely disposed seats (17, 19) about the perimeter of the cavity (16). The seats (17, 19) have inclined bottom surfaces (21) which displace radially inwardly a pair of seats (30) each having a cylindrical seat extension (34) terminating in a curved seat surface (38). The second shaft (22) has a head (24) with diametrically opposed recesses (26) each having a curved surface (28) therein. The head (24) of the second shaft (22) is captured between the seats (30) to provide a lash-free universal joint (10).
Abstract:
A mechanical actuator for a disc brake assembly comprises a cam shaft and a pair of toggles. The cam shaft is designed with different interfaces for the pair of toggles to minimize travel for the cam shaft and maximize clamping forces during a parking brake application for the disc brake assembly.
Abstract:
A piston pump includes a cylinder with a bore receiving the piston. The piston forms a central passage leading to a variable volume chamber and a check valve is disposed in the central passage. In addition, the cylinder includes a pair of ports which selectively communicate with the variable volume chamber. The pair of ports and the central passage communicate a reservoir with the variable volume chamber.
Abstract:
The radial gear driven piston pump (10) comprises a stationary pintle or pin (40) having a rotatable rotor (30) mounted thereon. The rotor (30) and pintle (40) are disposed within a pumping bore (18) that is eccentrically aligned relative to bore extensions (28) receiving the pintle (40). The rotor (30) is driven by an offset motor (12) which engages a periphery of the rotor (30). The pintle (40) has therein two pairs of longitudinal passages comprising supply (46, 53) and discharge (47, 54) channels which communicate with respective intake (41, 43) and exhaust (42, 44) ports within the pump housing (16). The rotor (30) has sets of axially offset pistons (90, 100) received within piston cavities (93, 93'). Each set of piston (90, 100) comprises a metal piston cap (95) having a central opening (90) which receives a longitudinal extension (97) of a piston sealing ring (98). Each piston sealing ring (98) has an opening (111) extending into the longitudinal extension (97) in order to house a spring which engages a recess (34) of the piston cavity (93) to bias the piston outwardly into engagement with a bearing mechanism (70) disposed within the pumping bore (18). Each piston cavity (93, 93') has an end opening (94, 94') communicating intermittently with the associated supply (46, 53) and discharge (47, 54) channels as the rotor (30) rotates about the pintle (40). The pump (10) provides a dual channel pumping function with as many pistons as desired for each channel.
Abstract:
A hydraulic brake booster includes a spool valve within a housing for communicating fluid pressure into a chamber for urging a piston in a direction actuating a master cylinder, thereby effecting a brake application. The communication between an inlet passage and the chamber is regulated by a land on the spool valve cooperating with a corresponding land on the housing. In order to prevent particles which are carried in the pressurized fluid from wedging in the interface between the land and the corresponding housing land, an additional land is provided on the spool valve. The additional land cooperates with another land on the housing to form a small clearance therebetween so that large particles in the fluid are prevented from wedging in the interface between the sensitive land and the corresponding land on the housing when the valve is in the brake-released position.
Abstract:
An accumulator for use in a brake booster having a housing with a piston located in a bore. The piston has a plug attached thereto. The piston moves in response to a predetermined thermal expansion of a fluid in the accumulator. A predetermined movement shears the plug from the piston to prevent damage to the housing by venting the bore to a reservoir.
Abstract:
A braking apparatus (28) includes a housing (38). The housing (38) includes therein: a master cylinder section (40) for supplying pressurized fluid to the brakes (24) of an automotive vehicle (10) to effect a brake application, a hydraulic booster section (42) for assisting the master cylinder section (40) to effect a brake application, a fluid pumping section (44) driven by an electric motor, for supplying pressurized fluid to the hydraulic booster section (42), and a reservoir section (46) supplying a single fluid to the sections 40, 42, and 44. The electric motor driving the fluid pumping section (44) receives energy from the vehicle (10) only in response to a need for braking. The brake booster (28) includes a fluid pressure accumulator (147) providing pressurized fluid to the booster section (42) during a brake application. The accumulator (147) also provides for power-assisted braking in the event of a failure of the motor-driven pumping section (44).
Abstract:
A hydraulic brake booster includes a housing 12 with a first chamber 40 and a second chamber 42. An input member 54 extends into the first chamber 40 and is exposed to the second chamber 42. The input member is movable within the first chamber 40 to increase fluid pressure within the second chamber 42 and this fluid pressure operates a control valve 90 to communicate fluid pressure to the first chamber 40. The fluid pressure in the first chamber 40 acts against the input to bias the same toward the second chamber 42. An output member 70 is movable in response to the fluid pressure within the second pressure chamber 42 to actuate braking.