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US3766735A Expired / Lapsed US ⏱️ 0.0 years remaining

Brake booster and master cylinder assembly

Assignee: Motors Liquidation Co
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Filing: 1972-05-31
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Granted: 1973-10-23
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Expires: 1992-05-31
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Abstract

Abstract A master cylinder assembly has a secondary piston assembly and a primary piston assembly mounted in a common bore to provide a primary pressurizing chamber between the piston assemblies and a secondary primary chamber between the secondary piston assembly and one end of the bore. The primary piston assembly is composed of two concentric pistons, one extending through a bore in the other. Two input members are provided, one of which is arranged to move both primary pistons concentrically under brake booster power to actuate the master cylinder, and the other of which is arranged to move only one of the primary pistons, without moving the other, to actuate the master cylinder manually when no power assist is available from the booster. The booster assembly is actuated through a manually moved push rod which in turn permits movement of a valve input member forming a part of the booster control valve assembly. The valve input member is arranged so that it normally follows movement of the push rod but is not positively attached thereto. A reaction system in the booster provides for booster ''''feel'''' to be transmitted to the input push rod. The booster control valve assembly is mounted in the booster power wall. The power wall includes one or more power diaphragms and is actuated by differential pressures imposed on opposite sides of the diaphragms under control of the control valve assembly. The power wall is connected to move the master cylinder input means which actuates both primary pistons, and is so arranged as to permit movement of the other master cylinder input means without requiring movement of the power wall when no booster assist force is available.

Inventors

  • 👤 D Nordeen

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-10 02:14
CPC Classifications
B; B60; B60T; B60T13/00; B60T13/10; B60T13/24; B60T13/46; B60T13/52; B60T13/573; B60T13/575; B60T13/565

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 264 words
A brake booster and master cylinder assembly comprising: a master cylinder housing having a bore, first and second concentric primary pistons and a secondary piston reciprocably received in said bore and defining therewith a primary pressurizing chamber between said primary and secondary pistons and a secondary pressurizing chamber between said secondary piston and one end of said bore, said second primary piston having on the end thereof opposite said secondary piston an apertured plate member adjacent and engageable with the end of said first primary piston opposite said secondary piston, and piston stop means in said bore, said plate member being axially intermediate said first primary piston and said stop means and engageable with said stop means and by said first primary piston to define the rest position of both of said primary pistons; first force transmitting means engaging said plate member axially opposite said first primary piston, and second force transmitting means extending through said apertured plate member and engaging said first primary piston for transmitting force to said first primary piston independently of said plate member and said second primary piston; and a booster having first output means and second output means and manual input means and booster power control means operatively controlled by movement of said manual input means, said second output means being connected to transmit booster generated force to said first and second force transmitting means upon power operation of said booster, said manual input means being connected to transmit manually generated force to said first output means through said second force transmitting means, independently of booster power operation.
Claim 2
Dependent Claim 264 words
A brake booster and master cylinder assembly comprising: a master cylinder housing having a bore, first and second concentric primary pistons and a secondary piston reciprocably received in said bore and defining therewith a primary pressurizing chamber between said primary and secondary pistons and a secondary pressurizing chamber between said secondary piston and one end of said bore, said second primary piston having on the end thereof opposite said secondary piston an apertured plate member adjacent and engageable with the end of said first primary piston opposite said secondary piston, and piston stop means in said bore, said plate member being axially intermediate said first primary piston and said stop means and engageable with said stop means and by said first primary piston to define the rest position of both of said primary pistons; first force transmitting means engaging said plate member axially opposite said first primary piston, and second force transmitting means extending through said apertured plate member and engaging said first primary piston for transmitting force to said first primary piston independently of said plate member and said second primary piston; and a booster having first output means and second output means and manual input means and booster power control means operatively controlled by movement of said manual input means, said second output means being connected to transmit booster generated force to said first and second force transmitting means upon power operation of said booster, said manual input means being connected to transmit manually generated force to said first output means through said second force transmitting means, independently of booster power operation.
Claim 3
Dependent Claim 278 words
A brake and booster and master assembly comprising: a brake booster having a housing, power wall means movable in said housing, a manual input member operably connected to an operator actuated brake member and reciprocal in said housing, said manual input member including a portion for transmitting input forces as said input member is reciprocated in said housing, a booster control valve operated by movement of said manual input member to cause said power wall means to move to a braking operative position when said manual input member is moved in response to braking action by an operator, manual output means moved in response to movement of said manual input member, a force reaction disc between said manual input member and said manual output means for transmitting reaction forces to said manual input member and to the operator from said first output means; a master cylinder having a first primary piston and a second primary piston for pressurizing brake fluid, a booster power output means including a tubular member with a first end around said reaction disc and extending from said power wall means to said primary pistons, a transfer plate member between said primary pistons and said tubular member for transmitting braking movement of said power wall meAns to both of said primary pistons for pressurizing fluid, said manual output means including a member operably engaged by and movable with said reaction disc and extending in bypass relation past said transfer plate member for engaging only said first primary piston to cause pressurization of fluid without movement of said second primary piston during operation of the brake assembly without power assist from said booster power wall mean.
Claim 4
Dependent Claim 278 words
A brake and booster and master assembly comprising: a brake booster having a housing, power wall means movable in said housing, a manual input member operably connected to an operator actuated brake member and reciprocal in said housing, said manual input member including a portion for transmitting input forces as said input member is reciprocated in said housing, a booster control valve operated by movement of said manual input member to cause said power wall means to move to a braking operative position when said manual input member is moved in response to braking action by an operator, manual output means moved in response to movement of said manual input member, a force reaction disc between said manual input member and said manual output means for transmitting reaction forces to said manual input member and to the operator from said first output means; a master cylinder having a first primary piston and a second primary piston for pressurizing brake fluid, a booster power output means including a tubular member with a first end around said reaction disc and extending from said power wall means to said primary pistons, a transfer plate member between said primary pistons and said tubular member for transmitting braking movement of said power wall meAns to both of said primary pistons for pressurizing fluid, said manual output means including a member operably engaged by and movable with said reaction disc and extending in bypass relation past said transfer plate member for engaging only said first primary piston to cause pressurization of fluid without movement of said second primary piston during operation of the brake assembly without power assist from said booster power wall mean.
Claim 5
Dependent Claim 295 words
A brake and booster and master assembly comprising: a brake booster having a housing, power wall means movable in said housing, a manual input member operably connected to an operator actuated brake member and reciprocal in said housing, said manual input member including a portion for transmitting input forces as said input member is reciprocated in said housing, a booster control valve operated by movement of said manual input member to cause said power wall means to move to a braking operative position when said manual input member is moved in response to braking action by an operator, manual output means moved in response to movement of said manual input member, a force reaction disc between said manual input member and said manual output means for transmitting reaction forces to said manual input member and to the operator from said first output means; a master cylinder having a first primary piston and a second primary piston for pressurizing brake fluid, a booster power output means including a tubular member with a first end around said reaction disc and extending from said power wall means to said primary pistons, a transfer plate member between said primary pistons and said tubular member for transmitting braking movement of said power wall means to both of said primary pistons for pressurizing fluid, said transfer plate member having apertures formed therethrough, said manual output means including a bifurcated member operably engaged by and movable with said reaction disc and having leg portions extending through said transfer plate apertures in bypass relation to said transfer plate for engaging only said first primary piston to cause pressurization of fluid without corresponding movement of said second primary piston during operation of the brake assembly without power assist from said booster power wall mean.
Claim 6
Dependent Claim 295 words
A brake and booster and master assembly comprising: a brake booster having a housing, power wall means movable in said housing, a manual input member operably connected to an operator actuated brake member and reciprocal in said housing, said manual input member including a portion for transmitting input forces as said input member is reciprocated in said housing, a booster control valve operated by movement of said manual input member to cause said power wall means to move to a braking operative position when said manual input member is moved in response to braking action by an operator, manual output means moved in response to movement of said manual input member, a force reaction disc between said manual input member and said manual output means for transmitting reaction forces to said manual input member and to the operator from said first output means; a master cylinder having a first primary piston and a second primary piston for pressurizing brake fluid, a booster power output means including a tubular member with a first end around said reaction disc and extending from said power wall means to said primary pistons, a transfer plate member between said primary pistons and said tubular member for transmitting braking movement of said power wall means to both of said primary pistons for pressurizing fluid, said transfer plate member having apertures formed therethrough, said manual output means including a bifurcated member operably engaged by and movable with said reaction disc and having leg portions extending through said transfer plate apertures in bypass relation to said transfer plate for engaging only said first primary piston to cause pressurization of fluid without corresponding movement of said second primary piston during operation of the brake assembly without power assist from said booster power wall mean.

References Cited (Backward Citations)

US3162018A Cited
US3473329A Cited
US3422622A Cited
US3540219A Cited
US3559406A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-10-22 1977-04-23 1977-10-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-10-22 1981-04-23 1981-10-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-10-22 1985-04-23 1985-10-23 $7700.00 Window Closed / Lapsed

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