US3659685A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Slack adjuster for disc brake
Assignee: Westinghouse Air Brake Co
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Filing: 1970-10-28
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Granted: 1972-05-02
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Expires: 1990-10-28
Abstract
Abstract A pneumatically controlled hydraulically actuated disc-type brake mechanism for use on a wheel and axle assembly of a railway vehicle truck includes a hydraulic-type slack adjuster mechanism automatically operative to compensate for wear of a braking element. The hydraulic-type slack adjuster mechanism comprises a variable volume accumulator into which a hydraulic medium or fluid is forced upon the occurrence of wear of a braking element while a brake application is in effect and from which hydraulic fluid subsequently flows to two pair of hydraulic brake applying cylinders upon initiating a brake release to increase the volume thereof thereby to compensate for brake element wear. Prior to completion of the brake release, hydraulic fluid flows from a storage reservoir to the accumulator to replace that previously supplied from the accumulator to the hydraulic brake applying cylinders.
Inventors
- 👤 Joseph G Stipanovic
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 17:58
CPC Classifications
F; F16; F16D; F16D55/00; F16D55/02; F16D55/22; F16D55/228; F16D65/00; F16D65/14; F16D65/16; F16D65/18; F16D65/38; F16D65/72; F16D65/74; F16D2121/00; F16D2121/02; F16D2125/00; F16D2125/02; F16D2125/026; F16D2125/10
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
480 words
In a hydro-pneumatic disc brake mechanism for applying a braking force to a rotatable member carried on a wheel and axle assembly, the combination comprising: a. a brake disc carried on the wheel and axle assembly, b. brake shoes movably mounted on the respective opposite sides of said brake disc, c. a casing having therein two parallel spaced apart bottomed bores extending inward from one end thereof, and being provided with two parallel spaced apart U-shaped arm members, each having one end integral with one side of said casing, the other end being disposed on one side of said brake disc and provided with a plurality of spaced apart parallel bores into one end of certain of which bores open one end of one of a plurality of spaced apart passageways provided in said arm member the other end of each of said plurality of passageways in said arm meMber opening into one of said bottomed bores in said casing, d. a pressure head secured to said one end of said casing and having therein two parallel spaced apart bottomed bores coaxial with said two bottomed bores in said casing and of relatively larger diameter, e. a pair of pistons operative respectively in said bottomed bores in said pressure head and movable in opposite directions responsively to application and release of pneumatic pressure to one side thereof, f. a pair of plungers each operatively connected to one of said pair of pistons and operable in one of said bottomed bores in said casing, g. a reservoir filled with a hydraulic medium, h. means for supplying said hydraulic medium from said reservoir to said bottomed bores in said casing, said hydraulic medium in said bottomed bores being subject to pressure upon movement of said pair of plungers in one direction, i. two pair of brake applying pistons, each pair being disposed in a pair of said certain spaced apart parallel bores in one of said arm members and movable responsively to hydraulic pressure established in said bottomed bores as communicated to said certain spaced apart parallel bores via said passageways and acting on said brake applying pistons for effecting movement of a corresponding one of said brake shoes into braking contact with one side of said brake disc and exerting a brake applying force thereon, j. two pair of brake releasing pistons, each pair being slidably disposed in another pair of said spaced apart parallel bores in one of said arm members and operably connected to one of said brake shoes, and k. two pair of release springs, each pair interposed between one pair of said brake releasing pistons and the corresponding arm member and effective to move a corresponding brake shoe to a release position out of contact with said brake disc in the absence of hydraulic pressure acting on the pair of brake applying pistons for said brake shoe.
Claim 2
Dependent Claim
480 words
In a hydro-pneumatic disc brake mechanism for applying a braking force to a rotatable member carried on a wheel and axle assembly, the combination comprising: a. a brake disc carried on the wheel and axle assembly, b. brake shoes movably mounted on the respective opposite sides of said brake disc, c. a casing having therein two parallel spaced apart bottomed bores extending inward from one end thereof, and being provided with two parallel spaced apart U-shaped arm members, each having one end integral with one side of said casing, the other end being disposed on one side of said brake disc and provided with a plurality of spaced apart parallel bores into one end of certain of which bores open one end of one of a plurality of spaced apart passageways provided in said arm member the other end of each of said plurality of passageways in said arm meMber opening into one of said bottomed bores in said casing, d. a pressure head secured to said one end of said casing and having therein two parallel spaced apart bottomed bores coaxial with said two bottomed bores in said casing and of relatively larger diameter, e. a pair of pistons operative respectively in said bottomed bores in said pressure head and movable in opposite directions responsively to application and release of pneumatic pressure to one side thereof, f. a pair of plungers each operatively connected to one of said pair of pistons and operable in one of said bottomed bores in said casing, g. a reservoir filled with a hydraulic medium, h. means for supplying said hydraulic medium from said reservoir to said bottomed bores in said casing, said hydraulic medium in said bottomed bores being subject to pressure upon movement of said pair of plungers in one direction, i. two pair of brake applying pistons, each pair being disposed in a pair of said certain spaced apart parallel bores in one of said arm members and movable responsively to hydraulic pressure established in said bottomed bores as communicated to said certain spaced apart parallel bores via said passageways and acting on said brake applying pistons for effecting movement of a corresponding one of said brake shoes into braking contact with one side of said brake disc and exerting a brake applying force thereon, j. two pair of brake releasing pistons, each pair being slidably disposed in another pair of said spaced apart parallel bores in one of said arm members and operably connected to one of said brake shoes, and k. two pair of release springs, each pair interposed between one pair of said brake releasing pistons and the corresponding arm member and effective to move a corresponding brake shoe to a release position out of contact with said brake disc in the absence of hydraulic pressure acting on the pair of brake applying pistons for said brake shoe.
Claim 3
Dependent Claim
466 words
In a hydro-pneumatic disc brake mechanism for applying a braking force to a rotatable member carried on a wheel and axle assembly, the combination comprising: a. a rotatable brake disc carried on the wheel and axle assembly, b. a brake shoe movably mounted on one side of said brake disc, c. a casing having therein two parallel spaced apart bottomed bores extending inward from one end thereof, and being provided with a U-shaped arm member having one end integral with one side of said casing, the other end being disposed on said one side of said brake disc and provided with a plurality of spaced apart parallel bores into one end of each of one pair of which opens one end of one of a plurality of spaced apart passageways provided in said arm member the other end of each of said plurality of passageways in said arm member opening into one of said bottomed bores in said casing, d. a pressure head secured to said one end of said casing and having therein two parallel spaced apart bottomed bores coaxial with said two bottomed bores in said casing and of relatively larger diameter, e. a pair of pistons operative respectively in said bottomed bores in said pressure head and movable in opposite directions responsively to application and release of pneumatic pressure to one side thereof, f. a pair of plungers each operatively connected to one of said pair of pistons and operable in one of said bottomed bores in said casing, g. a reservoir filled with a hydraulic medium, h. means for supplying said hydraulic medium from said reservoir to said bottomed bores in said casing, said hydraulic medium in said bottomed bores being subject to pressure upon movement of said pair of plungers in one direction, i. a pair of brake applying pistons disposed respectively in a pair of said certain spaced apart parallel bores in said arm member and movable responsively to hydraulic pressure established in said bottomed bores as communicated to said pair of said certain spaced apart parallel bOres via said pair of passageways and acting on said pair of brake applying pistons for effecting movement of said brake shoe into braking contact with said brake disc and exerting a brake applying force thereon, j. a pair of brake releasing pistons, each being slidably disposed in another one of said plurality of spaced apart parallel bores in said arm member and operably connected to said brake shoe, and k. a pair of release springs, each interposed between one of said pair of brake releasing pistons and said arm member and effective to move said brake shoe to a release position out of contact with said brake disc in the absence of hydraulic pressure acting on said pair of brake applying pistons.
Claim 4
Dependent Claim
466 words
In a hydro-pneumatic disc brake mechanism for applying a braking force to a rotatable member carried on a wheel and axle assembly, the combination comprising: a. a rotatable brake disc carried on the wheel and axle assembly, b. a brake shoe movably mounted on one side of said brake disc, c. a casing having therein two parallel spaced apart bottomed bores extending inward from one end thereof, and being provided with a U-shaped arm member having one end integral with one side of said casing, the other end being disposed on said one side of said brake disc and provided with a plurality of spaced apart parallel bores into one end of each of one pair of which opens one end of one of a plurality of spaced apart passageways provided in said arm member the other end of each of said plurality of passageways in said arm member opening into one of said bottomed bores in said casing, d. a pressure head secured to said one end of said casing and having therein two parallel spaced apart bottomed bores coaxial with said two bottomed bores in said casing and of relatively larger diameter, e. a pair of pistons operative respectively in said bottomed bores in said pressure head and movable in opposite directions responsively to application and release of pneumatic pressure to one side thereof, f. a pair of plungers each operatively connected to one of said pair of pistons and operable in one of said bottomed bores in said casing, g. a reservoir filled with a hydraulic medium, h. means for supplying said hydraulic medium from said reservoir to said bottomed bores in said casing, said hydraulic medium in said bottomed bores being subject to pressure upon movement of said pair of plungers in one direction, i. a pair of brake applying pistons disposed respectively in a pair of said certain spaced apart parallel bores in said arm member and movable responsively to hydraulic pressure established in said bottomed bores as communicated to said pair of said certain spaced apart parallel bOres via said pair of passageways and acting on said pair of brake applying pistons for effecting movement of said brake shoe into braking contact with said brake disc and exerting a brake applying force thereon, j. a pair of brake releasing pistons, each being slidably disposed in another one of said plurality of spaced apart parallel bores in said arm member and operably connected to said brake shoe, and k. a pair of release springs, each interposed between one of said pair of brake releasing pistons and said arm member and effective to move said brake shoe to a release position out of contact with said brake disc in the absence of hydraulic pressure acting on said pair of brake applying pistons.
Claim 5
Dependent Claim
20 words
a first one-way valve means controlling flow of said hydraulic medium from said reservoir to said plurality of intersecting bores,
Claim 6
Dependent Claim
20 words
a first one-way valve means controlling flow of said hydraulic medium from said reservoir to said plurality of intersecting bores,
Claim 7
Dependent Claim
60 words
In a hydro-pneumatic disc brake mechanism, as recited in claim 2, further characterized in that said means for supplying said hydraulic medium from said hydraulic reservoir to said bottomed bores in said casing comprises: a. valve means controlling flow of hydraulic medium from said reservoir to said bottomed bores, and b. hydro-pneumatic means for controlling operation of said valve means.
Claim 8
Dependent Claim
24 words
a second one-way valve means controlling flow of said hydraulic medium from said plurality of intersecting bores to said bottomed bore in said casing,
Claim 9
Dependent Claim
24 words
a second one-way valve means controlling flow of said hydraulic medium from said plurality of intersecting bores to said bottomed bore in said casing,
Claim 10
Dependent Claim
31 words
a spring-biased abutment operably disposed in one of said plurality of intersecting bores for increasing the volume of said one bore in response to the application of pressure to said abutment,
Claim 11
Dependent Claim
31 words
a spring-biased abutment operably disposed in one of said plurality of intersecting bores for increasing the volume of said one bore in response to the application of pressure to said abutment,
Claim 12
Dependent Claim
304 words
In a hydro-pneumatic disc brake mechanisms, as recited in claim 2, further characterized in that said means for supplying said hydraulic medium from said hydraulic reservoir to said bottomed bores in said casing comprises: a. a body member secured to said casing and having therein a plurality of intersecting bores, b. a first one-way valve means controlling flow of hydraulic medium from said reservoir to said plurality of intersecting bores, c. a second one-way valve means controlling flow of hydraulic medium from said plurality of intersecting bores to said bottomed bores in said casing, d. a spring-biased abutment operably disposed in one of said plurality of intersecting bores for increasing the volume of said one bore in response to the application of pressure to said abutment, e. abutment means operably disposed in another of said plurality of intersecting bores and movable in one direction to simultaneously render said first one-way valve means inoperative to control flow of hydraulic medium from said reservoir to said plurality of intersecting bores and to subject said spring-biased abutment to pressure to cause an increase in the volume of said one bore accordingly as said abutment means decreases the volume of said another bore, and subsequently movable in an opposite direction to successively render said spring-biased abutment operable to simultaneously decrease the volume of said one bore and effect flow therefrom past said second one-way valve means to said bottomed bores in said casing, and said first one-way valve means operable to cause flow of said hydraulic medium from said reservoir to said plurality of intersecting bores, and f. means responsive to excessive movement of one of said pair of pistons subject to pneumatic pressure in response to wear of said brake shoe for subjecting said abutment means to pneumatic pressure to cause movement thereof in said one direction.
Claim 13
Dependent Claim
138 words
abutment means operably disposed in another of said plurality of said intersecting bores and movable in one direction to simultaneously render said first one-way valve means inoperative to control flow of said hydraulic medium from said reservoir to said plurality of intersecting bores and to subject said spring-biased abutment to pressure to cause an increase in the volume of said one bore accordingly as said abutment means decreases the volume of said another bore, and subsequently movable in an opposite direction to successively render said spring-biased abutment operable to simultaneously decrease the volume of said one bore and effect flow therefrom past said second one-way valve means to said bottomed bore in said casing, and said first one-way valve means opErable to cause flow of said hydraulic medium from said reservoir to said plurality of intersecting bores, and
Claim 14
Dependent Claim
138 words
abutment means operably disposed in another of said plurality of said intersecting bores and movable in one direction to simultaneously render said first one-way valve means inoperative to control flow of said hydraulic medium from said reservoir to said plurality of intersecting bores and to subject said spring-biased abutment to pressure to cause an increase in the volume of said one bore accordingly as said abutment means decreases the volume of said another bore, and subsequently movable in an opposite direction to successively render said spring-biased abutment operable to simultaneously decrease the volume of said one bore and effect flow therefrom past said second one-way valve means to said bottomed bore in said casing, and said first one-way valve means opErable to cause flow of said hydraulic medium from said reservoir to said plurality of intersecting bores, and
Claim 15
Dependent Claim
27 words
In a hydro-pneumatic disc brake mechanism, as recited in claim 4, further characterized by means effective to cause movement of said abutment means in said opposite direction.
Claim 16
Dependent Claim
68 words
In a hydro-pneumatic disc brake mechanism, as recited in claim 4, further characterized in that said second one-way valve means is rendered inoperative to control flow of hydraulic medium from said plurality of bores to said bottomed bores in said casing so long as the pressure established in said bottomed bores by the respective plungers therein exceeds the pressure established on said spring-biased abutment by said abutment means.
Claim 17
Dependent Claim
188 words
means responsive to excessive movement of said piston subject to pneumatic pressure in response to wear of said brake shoe for subjecting said abutment means to pneumatic pressure to cause movement thereof in said one direction, i. a brake applying piston disposed in said one of said plurality of spaced apart parallel bores in said arm member, said brake applying piston being movable responsively to hydraulic pressure established in said bottomed bore in said casing as communicated to said one bore via said passageway in said arm member and acting on said brake applying piston for effecting movement of said brake shoe into contact with said brake disc and exerting a brake applying force thereon, j. a brake releasing piston slidably disposed in another of said plurality of spaced apart parallel bores in said arm member and operably connected to said brake shoe, and k. a release spring interposed between said break releasing piston and said arm member and effective to move said brake shoe to a release position out of contact with said brake disc in the absence of hydraulic pressure acting on said brake applying piston.
Claim 18
Dependent Claim
188 words
means responsive to excessive movement of said piston subject to pneumatic pressure in response to wear of said brake shoe for subjecting said abutment means to pneumatic pressure to cause movement thereof in said one direction, i. a brake applying piston disposed in said one of said plurality of spaced apart parallel bores in said arm member, said brake applying piston being movable responsively to hydraulic pressure established in said bottomed bore in said casing as communicated to said one bore via said passageway in said arm member and acting on said brake applying piston for effecting movement of said brake shoe into contact with said brake disc and exerting a brake applying force thereon, j. a brake releasing piston slidably disposed in another of said plurality of spaced apart parallel bores in said arm member and operably connected to said brake shoe, and k. a release spring interposed between said break releasing piston and said arm member and effective to move said brake shoe to a release position out of contact with said brake disc in the absence of hydraulic pressure acting on said brake applying piston.
Claim 19
Dependent Claim
62 words
In a hydro-pneumatic disc brake mechanism, as recited in claim 4, further characterized in that said abutment means comprises: a. a piston slidably and sealably mounted in said another bore, and b. a diaphragm in coaxial alignment with said piston and having one side thereof disposed in abutting relation to an adjacent side of sAid piston and constantly subject to atmospheric pressure.
Claim 20
Dependent Claim
29 words
In a hydro-pneumatic disc brake mechanism, as recited in claim 4, further characterized by means normally biasing said first and said second one-way valve means to a closed position.
Claim 21
Dependent Claim
53 words
In a hydro-pneumatic disc brake mechanism, as recited in claim 4, further characterized in that the axis of said spring biased abutment, and the axes of said first and said second one-way valve means lie in a common plane, and the axis of said another bore forms a right angle with said plane.
Claim 22
Dependent Claim
32 words
In a hydro-pneumatic disc brake mechanism, as recited in claim 4, further characterized by means for controlling the rate at which pneumatic pressure is supplied to and released from said abutment means.
Claim 23
Dependent Claim
53 words
In a hydro-pneumatic disc brake mechanism, as recited in claim 4, further characterized in that said spring-biased abutment, upon each successive operation to decrease the volume of said one bore, effects flow of the same quantity of hydraulic medium past said second one-way flow valve means to said bottomed bores in said casing.
Claim 24
Dependent Claim
261 words
In a hydro-pneumatic disc brake mechanism for applying a braking force to a rotatable member carried on a wheel and axle assembly, the combination comprising: a. a rotatable brake disc carried on the wheel and axle assembly, b. a brake shoe movably mounted on one side of said brake disc, c. a casing having therein a bottomed bore extending inward from one end thereof, said casing being provided with an arm member that has one end integral therewith, the other end being disposed on said one side of said brake disc and provided with a plurality of spaced apart parallel bores into one end of one of which opens one end of a passageway extending through said arm member and opening at its other end into said bottomed bore in said casing, d. a pressure head secured to said one end of said casing and having therein a bottomed bore coaxial with said bottomed bore in said casing and of relatively larger diameter, e. a piston sealably and slidably disposed in said bottomed bore in said pressure head and movable in opposite directions responsively to application and release of pneumatic pressure to one side thereof, f. a plunger operatively connected to said piston and operable in said bottomed bore in said casing, g. a reservoir filled with a hydraulic medium, and h. means for supplying said hydraulic medium from said reservoir to said bottomed bore in said casing, said hydraulic medium in said bottomed bore being subject to pressure upon movement of said plunger in one direction, and said means comprising:
Claim 25
Dependent Claim
261 words
In a hydro-pneumatic disc brake mechanism for applying a braking force to a rotatable member carried on a wheel and axle assembly, the combination comprising: a. a rotatable brake disc carried on the wheel and axle assembly, b. a brake shoe movably mounted on one side of said brake disc, c. a casing having therein a bottomed bore extending inward from one end thereof, said casing being provided with an arm member that has one end integral therewith, the other end being disposed on said one side of said brake disc and provided with a plurality of spaced apart parallel bores into one end of one of which opens one end of a passageway extending through said arm member and opening at its other end into said bottomed bore in said casing, d. a pressure head secured to said one end of said casing and having therein a bottomed bore coaxial with said bottomed bore in said casing and of relatively larger diameter, e. a piston sealably and slidably disposed in said bottomed bore in said pressure head and movable in opposite directions responsively to application and release of pneumatic pressure to one side thereof, f. a plunger operatively connected to said piston and operable in said bottomed bore in said casing, g. a reservoir filled with a hydraulic medium, and h. means for supplying said hydraulic medium from said reservoir to said bottomed bore in said casing, said hydraulic medium in said bottomed bore being subject to pressure upon movement of said plunger in one direction, and said means comprising:
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-02 | 1975-11-01 | 1976-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-02 | 1979-11-01 | 1980-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-02 | 1983-11-01 | 1984-05-02 | $7700.00 | Window Closed / Lapsed |