Claims
- 1. A vehicular brake system comprising:
(A) at least one hydraulically actuated vehicle brake; (B) a brake pedal which is movable through a braking cycle in which said brake pedal moves from a released position, through a service braking stroke, to a latched position, is latched in the latched position, and then moves back to the released position; (C) a master cylinder housing which has a front wall; (D) a master cylinder which is mounted on said housing, which has an inlet in fluid communication with a hydraulic fluid reservoir and an outlet in fluid communication with said brake, which is actuated by said brake pedal to engage said brake when said bake pedal travels through said service braking stroke, and which is latched in said actuated position when said brake pedal is latched in said latched position thereof; (E) a hydraulic accumulator which is coupled to said master cylinder, 15 which extends toward said front wall of said mounting bracket, and which is dimensioned and configured to store energy generated by said master cylinder upon actuation thereof and to use said energy to assist in holding said brake in the engaged condition thereof when said master cylinder is locked in said actuated position thereof, said accumulator including 1) a compression spring having an outer, stationary end and an inner, movable end and 2) a compression plate on which said inner end of said spring rests; and (F) a booster which is automatically operated during at least a portion of a first braking cycle of said brake system to boost an energy storage level of said accumulator during another, subsequent braking cycle without requiring manual deactivation of said booster, said booster comprising 1) an indexing arm which is pivotably mounted on said front wall of said mounting bracket; 2) a stack of spacer plates which are mounted on said indexing arm, and each of which has an inner surface which faces said compression plate and an outer 30 surface which is disposed opposite said inner surface, 3) a biasing arrangement which biases said spacer plates toward said compression plate and which permits limited movement of said spacer plates relative to said indexing arm upon contact between said spacer plates and a peripheral surface of said compression plate, 4) a return spring which biases said indexing arm toward a position in which said spacer plates engage said compression plate, and 5) an actuator arm which extends rearwardly from said indexing arm toward said brake pedal, wherein said actuator arm cooperates with said brake pedal such that,
a) during movement of said brake pedal into the latched position following a service braking stroke, said actuator arm is driven by said brake pedal to move said indexing arm into a disengaged position in which all of said spacer plates are spaced radially from said peripheral surface of said compression plate in order to permit unhindered axial movement of said compression plate past said spacer plates, and b) upon release of said brake pedal from said latched position, said return spring automatically moves said indexing arm to an engaged position in which at least one spacer plate of said stack is lodged between an axial surface of said compression plate and said front wall of said master cylinder housing.
- 2. A brake booster comprising:
(A) an indexing arm which is configured for pivotal mounting on a surface of a brake system, said indexing arm having inner and outer surfaces and front and rear surfaces; (B) an actuator arm which is coupled to said indexing arm, which extends beyond said rear surface of said indexing arm, and which is configured for engagement with a brake pedal; and (C) a variable thickness spacer which is mounted on said indexing arm and which is configured to selectively lodge between an axial surface of an accumulator 10 and another surface of the brake system when said indexing arm is driven into an engaged position thereof in response to release of the brake pedal from a latched position thereof.
- 3. The booster as recited in claim 2, further comprising a return spring which is coupled to said indexing arm which is configured to bias said indexing arm toward said engaged position.
- 4. The indexing arm as recited in claim 2, wherein said spacer includes a stack of spacer plates, each of which has an inner surface which is configured to face the accumulator and a outer surface which is disposed opposite said inner surface, and further comprising a biasing arrangement which configured to bias said spacer plates toward a said inner surface of said indexing arm while permitting limited movement of said spacer plates relative to said indexing arm.
- 5. A method comprising:
(A) actuating a brake pedal of a vehicular brake system from a released position and through a brake and latch and phase of a first braking cycle to sequentially apply at least one hydraulically actuated brake of said vehicle and latch said brake in the applied condition, wherein, during at least a latter portion of said brake and latch phase, an accumulator is energized at least indirectly by movement of said brake pedal to store energy in said accumulator; then (B) releasing said brake pedal during a return phase of said first braking cycle to return said brake to said released position, wherein, during the return phase, only a portion of the energy stored by said accumulator during the first actuating step is released; (C) actuating said brake pedal through a brake and latch phase of a second braking cycle to sequentially apply said brake and latch said brake in said applied condition and to store energy in said accumulator, wherein a magnitude of energy stored by said accumulator during said second braking cycle is greater than a magnitude of energy stored during said first braking cycle.
- 6. The method as recited in claim 5, further comprising completing N+M additional braking cycles, where N and M are both greater than 1, and wherein said accumulator stores at least essentially the same magnitude of the energy during each of the N+1st through Mth braking cycles.
- 7. The method as recited in claim 6, wherein said accumulator releases at least essentially the same magnitude of energy during the release phase of each of the N+1st through Mth braking cycles.
- 8. The method as recited in claim 6, wherein a compression spring of said accumulator is compressed to lengths L1 and L2 during the brake and latch phases of the first and second braking cycles, respectively, L2 being less than L1, and wherein said spring is compressed to a length LF during the brake and latch phase of each of the N+1st and subsequent braking cycles, LF being less than L2.
- 9. The method as recited in claim 8, wherein a movable axial surface of said accumulator is located at an initial position P1 prior to the first braking cycle, and further comprising returning said axial surface to a second position P2 during the release phase of the first braking cycle and then holding said axial surface in the position P2 until the brake and latch phase of the second braking cycle, P2 being spaced from P1 by a distance L1-L2.
- 10. The method as recited in claim 9, wherein the holding step comprises inserting a spacer of an effective thickness equal to P2 between said axial surface of said accumulator and as stationary surface of said brake system, thereby preventing further movement of said axial surface toward said stationary surface and preventing further energy release.
- 11. The method as recited in claim 10, wherein said spacer is of a variable effective thickness, and wherein following each of the N+1″ and subsequent braking cycles, the spacer has an effective thickness Pf equal to L1-Lf.
- 12. The method as recited in claim 10, wherein said spacer comprises a stack of spacer plates mounted on an indexing arm, and wherein an effective thickness of said spacer after each braking cycle is determined by the number of plates lodged betweens said axial surface of said accumulator and said stationary surface of said braking system at that time.
- 13. The method as recited in claim 10, wherein said spacer is mounted on an indexing arm that automatically 1) moves said spacer away from said accumulator during an energy storage portion of the brake and latch phase of each braking cycle in which said accumulator spring is being compressed and 2) moves into a position in which said spacer lodges between said axial surface of said accumulator and said stationary surface during the release phase of each braking cycle.
- 14. The method as recited in claim 13, wherein said brake pedal drives said indexing arm away from said accumulator during said energy storage portion of each braking cycle and a return spring drives said indexing arm toward said accumulator during the release phase of each braking cycle.
- 15. A vehicle comprising:
(A) at least front and rear wheels; and (B) a combined service/parking brake system including
(1) a plurality of hydraulically actuated brakes, one of which 5 brakes each of said wheels, and (2) a brake actuator assembly that can be operated to effect both service braking and park and hold braking, wherein said brake system is configured such that all of said brakes are engaged during park and hold braking.
- 16. The vehicle as recited in claim 15, wherein said vehicle is a four-wheeled vehicle having two front wheels an two rear wheels, and wherein said brake system is configured such that both front brakes and both rear brakes are engaged during park and hold braking.
- 17. A vehicle brake system comprising:
(A) at least first and second hydraulically-actuated vehicle brakes; (B) a manually actuated multi-outlet master cylinder which has an inlet in fluid communication with a hydraulic fluid reservoir and at least first and second outlets in fluid communication with said first and second brakes, respectively, wherein said master cylinder is configured to be locked in an actuated position thereof to hold said brakes in an engaged condition; and (C) a hydraulic accumulator which has an inlet in fluid communication with at least one of said outlets of said master cylinder and which is dimensioned and configured to store energy generated by said master cylinder upon actuation thereof and to use said energy to assist in holding at least one of said first and second brakes in said engaged condition when said master cylinder is locked in said actuated position thereof.
- 18. The vehicle brake system as recited in claim 17, wherein said inlet of said accumulator is in fluid communication with only one of said outlets of said master cylinder and is dimensioned and configured to assist in holding only one of said first and second brakes in said engaged condition when said master cylinder is locked in said actuated position thereof.
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application Ser. No. 10/308,970, filed Dec. 3, 2002, which is a continuation-in-part of U.S. patent application Ser. No. 09/914,867, filed Mar. 13, 2002, which is a national phase of PCT Application Serial No. PCT/US00/05427, filed Mar. 2, 2000, which claims the benefit of priority of U.S. Provisional Application Ser. No. 60/122,405, filed Mar. 2, 1999, the entire contents of each of which are hereby expressly incorporated by reference into the present application.
Provisional Applications (1)
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Date |
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60122405 |
Mar 1999 |
US |
Divisions (1)
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Number |
Date |
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Parent |
10308970 |
Dec 2002 |
US |
Child |
10900616 |
Jul 2004 |
US |
Continuation in Parts (1)
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09914867 |
Mar 2002 |
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10308970 |
Dec 2002 |
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