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US3709568A Expired / Lapsed US ⏱️ 0.0 years remaining

Hydraulic brake pressure control system and method for vehicles

Assignee: Aisin Corp
•
Filing: 1970-05-08
•
Granted: 1973-01-09
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Expires: 1990-05-08
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Abstract

Abstract In a hydraulic brake pressure control system for vehicles having a brake regulator comprising a cylinder, a differential piston provided with small and large effective surfaces and engaged in the cylinder, which subdivides the cylinder inside into two chambers, a control valve to open or shut off intercommunication between the two chambers by means of hydraulic pressure differences produced by the differential piston, a valve spring biasing the piston to hold the control valve normally open, predetermining the piston operation start, and also a wheel load sensing apparatus to vary the effect of the valve spring in response to changes of the distance between the two masses separated by the vehicle suspension system, improvements, wherein, are to make the wheel load sensing apparatus have little effect toward the piston in the intermediate point of the largest relative changing amount between the two masses, the valve starting its operation only by the predetermined load of the valve spring and also to increase and decrease the biasing force of the valve spring onto the piston with a switchover point of said intermediate one.

Inventors

  • 👤 H Miyake
  • 👤 S Kawai

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 01:14
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/18; B60T8/1806; B60T8/1837; B60T8/185

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 217 words
In a vehicle having a body frame and wheel axle support means separated from each other by a suspension system, wheel brake cylinders, a master cylinder and a pressure fluid braking circuit connecting said braking cylinders to said master cylinder, the combination of a brake regulator with wheel load sensing means connected to the regulator for controlling operation of the regulator, said regulator being secured to one of said body frame and wheel axle support means and including a cylinder, a differential piston subdividing the cylinder interior into two chambers facing piston surfaces of different areas and connected respectively to the master cylinder and the brake cylinders, valve means for controlling the intercommunication of said two chambers engaging said piston, and spring means biasing the piston in the direction to keep said valve means normally open, said wheel load sensing means including a leaf spring pivoted at one end to said body frame and at the other end to said wheel axle support means, and said leaf spring engaging said piston of the regulator through an interposed ball at a fulcrum point between the ends of the leaf spring and close to one end so as to exert a biasing force axially of said piston to regulate the biasing force of said spring means of the regulator.
Claim 2
Dependent Claim 217 words
In a vehicle having a body frame and wheel axle support means separated from each other by a suspension system, wheel brake cylinders, a master cylinder and a pressure fluid braking circuit connecting said braking cylinders to said master cylinder, the combination of a brake regulator with wheel load sensing means connected to the regulator for controlling operation of the regulator, said regulator being secured to one of said body frame and wheel axle support means and including a cylinder, a differential piston subdividing the cylinder interior into two chambers facing piston surfaces of different areas and connected respectively to the master cylinder and the brake cylinders, valve means for controlling the intercommunication of said two chambers engaging said piston, and spring means biasing the piston in the direction to keep said valve means normally open, said wheel load sensing means including a leaf spring pivoted at one end to said body frame and at the other end to said wheel axle support means, and said leaf spring engaging said piston of the regulator through an interposed ball at a fulcrum point between the ends of the leaf spring and close to one end so as to exert a biasing force axially of said piston to regulate the biasing force of said spring means of the regulator.
Claim 3
Dependent Claim 103 words
The combination set forth in claim 1, wherein the end of said leaf spring closer to the fulcrum is pivoted on a bracket which also holds the brake regulator and the other end of the leaf spring is pivoted to one end of an arm whose other end is pivoted to one of said body frame and wheel axle support means, said arm being adjustable and including rotatable bolts and nuts threaded on both ends thereof to change the length of the arm, the changes of length of said arm enabling modulation of the force of said spring means against the regulator piston.
Claim 4
Dependent Claim 50 words
The combination as set forth in claim 2, wherein said leaf spring is provided with an eye at each end, one of said eyes being engaged on a shaft projecting from said body frame and the other eye being mounted on a shaft projecting from said wheel axle support means.
Claim 5
Dependent Claim 30 words
The combination as set forth in claim 3, wherein said one eye member is mounted on a shaft projecting from said bracket, said bracket being secured to said body frame.
Claim 6
Dependent Claim 37 words
The combination as set forth in claim 4, wherein said eye at the other end of the leaf spring is mounted on a shaft projecting from said arm which is secured to said wheel axle support means.
Claim 7
Dependent Claim 29 words
The combination as set forth in claim 3, wherein an elastic grommet is positioned between each of said eye members of the leaf spring and the mounting shaft therefor.
Claim 8
Dependent Claim 52 words
The combination as set forth in claim 1, wherein said leaf spring is bent double at one end, the friction force between the two laminations of the bent spring absorbing the vibration of the leaf spring whereby to more accurately transmit wheel load forces of the leaf spring to the regulator piston.
Claim 9
Dependent Claim 23 words
The combination as set forth in claim 7, wherein an elastic member is placed between the two laminations of the doubled leaf spring.
Claim 10
Dependent Claim 264 words
In a vehicle having a body frame and wheel axle support means separated from each other by a suspension system including spring elements, wheel brake cylinders, a master cylinder and a pressure fluid braking circuit connecting said brake cylinders to said master cylinder, the combination of a brake regulator with wheel load sensing means connected to the regulator for controlling operation of the regulator, said regulator being secured to one of said body frame and wheel axle support means and including a cylinder, a differential piston subdividing the cylinder interior into two chambers facing piston surfaces of different areas and connected respectively to the master cylinder and the brAke cylinders, valve means for controlling the intercommunication of said two chambers engaging said piston, and spring means biasing the piston in the direction to keep said valve means normally open, said wheel load sensing means including a leaf spring pivoted at one end to said body frame and at the other end to said wheel axle support means through an adjustable arm, said leaf spring being separate from, additional to and independent of said spring elements of the suspension system and engaging said piston of the regulator at a fulcrum point between the ends of the leaf spring and close to one end so as to exert a biasing force axially of the piston to regulate the biasing force of said spring means of the regulator, whereby said leaf spring because of its independence of the suspension system and its pivotal support through said arm conducts force of bending action only to the regulator piston.
Claim 11
Dependent Claim 264 words
In a vehicle having a body frame and wheel axle support means separated from each other by a suspension system including spring elements, wheel brake cylinders, a master cylinder and a pressure fluid braking circuit connecting said brake cylinders to said master cylinder, the combination of a brake regulator with wheel load sensing means connected to the regulator for controlling operation of the regulator, said regulator being secured to one of said body frame and wheel axle support means and including a cylinder, a differential piston subdividing the cylinder interior into two chambers facing piston surfaces of different areas and connected respectively to the master cylinder and the brAke cylinders, valve means for controlling the intercommunication of said two chambers engaging said piston, and spring means biasing the piston in the direction to keep said valve means normally open, said wheel load sensing means including a leaf spring pivoted at one end to said body frame and at the other end to said wheel axle support means through an adjustable arm, said leaf spring being separate from, additional to and independent of said spring elements of the suspension system and engaging said piston of the regulator at a fulcrum point between the ends of the leaf spring and close to one end so as to exert a biasing force axially of the piston to regulate the biasing force of said spring means of the regulator, whereby said leaf spring because of its independence of the suspension system and its pivotal support through said arm conducts force of bending action only to the regulator piston.
Claim 12
Dependent Claim 27 words
The combination set forth in claim 9, wherein said leaf spring directly engages said piston of the regulator at said fulcrum point without interposition of other elements.
Claim 13
Dependent Claim 31 words
The combination as set forth in claim 10, wherein said leaf spring passes swingably through an opening provided in the outer end of said piston which juts out from its cylinder.

References Cited (Backward Citations)

US3199928A Cited
US3379479A Cited
US3442557A Cited
US3506313A Cited
DE1906461A1 Cited
US3576350A Cited
DE2000053A1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-01-09 1976-07-10 1977-01-09 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-01-09 1980-07-10 1981-01-09 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-01-09 1984-07-10 1985-01-09 $7700.00 Window Closed / Lapsed

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