Patent US5222787A successfully refreshed from Google Patents.
US5222787A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electro-hydraulic braking system
Assignee: Robert Bosch Technology Corp
•
Filing: 1990-11-20
•
Granted: 1993-06-29
•
Expires: 2010-11-20
Abstract
Abstract A braking system (8) comprising: a master cylinder (10); rear brakes (12a,b) communicated to the master cylinder (10); front brakes (14a,b) hydraulically isolated from the rear brakes; an isolation valve (16; 16') interposing the master cylinder (10) and the front brakes (14a,b) having a first state communicating the master cylinder to the front brakes and a second state isolating the master from the front brakes and connecting a pump (42) to the front brakes; a motor (44) for powering the pump (42); a reservoir (54) communicated to an inlet of the pump (42); a control unit (40) for causing front brake pressure to follow rear brake pressure comprising: a first pressure sensor (30) for generating a signal indicative of rear brake pressure; electric proportioning device (94) for generating a commanded front brake pressure signal (P C ); a second pressure sensor (32) for generating a signal of actual front brake pressure (P A ); a comparator (96) for comparing the command brake pressure signal to the actual brake pressure signal and for generating an error signal (P E ); a motor control circuit responsive to an error signal for activating the motor and for powering the pump (42).
Inventors
- 👤 William C. Eddy
- 👤 Kenneth S. Towers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 07:10
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/32; B60T8/34; B60T8/40; B60T8/4072; B60T8/26; B60T8/266
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
236 words
A braking system comprising: a master cylinder (10); rear brakes (12a,b) communicated to the master cylinder (10); front brakes (14a,b) hydraulically isolated from the rear brakes; isolation valve means (16; 16')interposing the master cylinder 10 and the front brakes (14a,b) having a first state communicating the master cylinder to the front brakes and a second state isolating the master cylinder from the front brakes and connecting a pump (42) to the front brakes; a motor (44) for powering the pump (42) in response to a control signal; a reservoir (54) communicated to an inlet of the pump (42); control unit means (40) for monitoring rear brake pressure and for generating the control signal, responsive to rear brake pressure, activating the motor thereby causing the pump to generate pressure in the front brakes proportional to rear brake pressure, a first pressure sensor (30) for generating a signal indicative of rear brake pressure; electric proportioning means (94) for generating a commanded front brake pressure signal (P C ); a second pressure sensor (32) for generating a signal indicative of rear brake pressure; comparison means (96) for comparing the command brake pressure signal to the actual brake pressure signal and for generating an error signal (P E ); motor control means (102, 104, 110, 120, 122, QA, QB) responsive to the error signal for generating the control signal and for activating the motor and for powering the pump (42).
Claim 2
Dependent Claim
236 words
A braking system comprising: a master cylinder (10); rear brakes (12a,b) communicated to the master cylinder (10); front brakes (14a,b) hydraulically isolated from the rear brakes; isolation valve means (16; 16')interposing the master cylinder 10 and the front brakes (14a,b) having a first state communicating the master cylinder to the front brakes and a second state isolating the master cylinder from the front brakes and connecting a pump (42) to the front brakes; a motor (44) for powering the pump (42) in response to a control signal; a reservoir (54) communicated to an inlet of the pump (42); control unit means (40) for monitoring rear brake pressure and for generating the control signal, responsive to rear brake pressure, activating the motor thereby causing the pump to generate pressure in the front brakes proportional to rear brake pressure, a first pressure sensor (30) for generating a signal indicative of rear brake pressure; electric proportioning means (94) for generating a commanded front brake pressure signal (P C ); a second pressure sensor (32) for generating a signal indicative of rear brake pressure; comparison means (96) for comparing the command brake pressure signal to the actual brake pressure signal and for generating an error signal (P E ); motor control means (102, 104, 110, 120, 122, QA, QB) responsive to the error signal for generating the control signal and for activating the motor and for powering the pump (42).
Claim 3
Dependent Claim
42 words
The system as defined in claim 1 wherein the isolation valve means (16;16') includes a pressure operated isolation valve (16) responsive to pressure applied by the pump (42), such pressure causing the pressure operated isolation valve to change to its second state.
Claim 4
Dependent Claim
46 words
The system as defined in claim 1 wherein the isolation valve means includes an electrically operated isolation valve (16') interposing the master cylinder (10) and the front brakes (14a,b) and responsive to an error signal, for causing such isolation valve to operate in its second state.
Claim 5
Dependent Claim
22 words
The system as defined in claim 1 wherein a first orifice (56) is connected across the pump (42) to a reservoir (54).
Claim 6
Dependent Claim
35 words
The system as defined in claim 4 wherein an electrically operated dump valve (57) is connected across the pump (42) to the sump (54) and responsive to a control signal for relieving front brake pressure.
Claim 7
Dependent Claim
30 words
The system as defined in claim 1 including first means for delaying the operating of the rear brakes (12a,b) until at least a time when the front brakes become activated.
Claim 8
Dependent Claim
49 words
The system as defined in claim 6 wherein the first means includes a check valve means (20) in circuit between the master cylinder (10) and the rear brakes for permitting an unrestricted decay of rear brake pressure and a second orifice (22) in parallel with the check valve means.
Claim 9
Dependent Claim
242 words
In a braking system (8) having rear brakes (12a,b) communicated to a master cylinder (10) and front brakes (14a,b) hydraulically isolated from the rear brakes; the improvement comprising: isolation valve means (16; 16') interposing a master cylinder (10) and the front brakes (14a,b) having a first state communicating the master cylinder to the front brakes and a second state isolating the master cylinder from the front brakes and connecting a pump (42) to the front brakes; a motor (44) for powering the pump (42) in response to a control signal; a reservoir (54) communicated to an inlet of the pump (42); control unit means (40) for monitoring rear brake pressure and for generating the control signal, responsive to rear brake pressure, activating the motor thereby causing the pump to generating pressure in the front brakes proportional to rear brake pressure, a first pressure sensor (30) for generating a signal indicative of rear brake pressure; electric proportioning means (94) for generating a commanded front rake pressure signal (P C ); a second pressure sensor (32) for generating a signal of actual front brake pressure (P A ); comparison means (96) for comparing the command brake pressure signal to the actual brake pressure signal and for generating an error signal (P E ); motor control means (102, 104, 110, 120, 122, QA, QB), responsive to the error signal for generating the control signal and for activating the motor and for powering the pump (42).
Claim 10
Dependent Claim
242 words
In a braking system (8) having rear brakes (12a,b) communicated to a master cylinder (10) and front brakes (14a,b) hydraulically isolated from the rear brakes; the improvement comprising: isolation valve means (16; 16') interposing a master cylinder (10) and the front brakes (14a,b) having a first state communicating the master cylinder to the front brakes and a second state isolating the master cylinder from the front brakes and connecting a pump (42) to the front brakes; a motor (44) for powering the pump (42) in response to a control signal; a reservoir (54) communicated to an inlet of the pump (42); control unit means (40) for monitoring rear brake pressure and for generating the control signal, responsive to rear brake pressure, activating the motor thereby causing the pump to generating pressure in the front brakes proportional to rear brake pressure, a first pressure sensor (30) for generating a signal indicative of rear brake pressure; electric proportioning means (94) for generating a commanded front rake pressure signal (P C ); a second pressure sensor (32) for generating a signal of actual front brake pressure (P A ); comparison means (96) for comparing the command brake pressure signal to the actual brake pressure signal and for generating an error signal (P E ); motor control means (102, 104, 110, 120, 122, QA, QB), responsive to the error signal for generating the control signal and for activating the motor and for powering the pump (42).
Claim 11
Dependent Claim
48 words
The system as defined in claim 8 wherein the isolation valve means (16; 16') includes a pressure operated isolation valve (16') interposing the master cylinder (10) and the front brakes (14a,b) and responsive to an error signal, for causing the isolation valve to operate in its second state.
Claim 12
Dependent Claim
48 words
The system as defined in claim 8 wherein the isolation valve means (16; 16') includes an electrically operated isolation valve (16') interposing the master cylinder (10) and the front brakes (14a,b) and responsive to an error signal, for causing the isolation valve to operate in its second state.
Claim 13
Dependent Claim
22 words
The system as defined in claim 8 wherein a first orifice (56) is connected across the pump (42) to the reservoir (54).
Claim 14
Dependent Claim
35 words
The system as defined in claim 11 wherein an electrically operated dump valve (57) is connected across the pump (42) to the sump (54) and responsive to a control signal for relieving front brake pressure.
Claim 15
Dependent Claim
30 words
The system as defined in claim 8 including first means for delaying the operating of the rear brakes (12a,b) until at least a time when the front brakes become activated.
Claim 16
Dependent Claim
49 words
The system as defined in claim 13 wherein the first means includes a check valve means (20) in circuit between the master cylinder (10) and the rear brakes for permitting an unrestricted decay of rear brake pressure and a second orifice (22) in parallel with the check valve means.
References Cited (Backward Citations)
US3814484A
Cited
US3825308A
Cited
US4632467A
Cited
US4674804A
Cited
US4637664A
Cited
US4890890A
Cited
US4790607A
Cited
US4805105A
Cited
US4795219A
Cited
US4852008A
Cited
US4824183A
Cited
US4943123A
Cited
US5015040A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-06-28 | 1996-12-28 | 1997-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-06-28 | 2000-12-28 | 2001-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-06-28 | 2004-12-28 | 2005-06-29 | $7700.00 | Window Closed / Lapsed |