US5334983A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Doppler-effect ground speed sensor for use with a brake system
Assignee: Toyota Motor Corp
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Filing: 1992-09-10
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Granted: 1994-08-02
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Expires: 2012-09-10
Abstract
Abstract Vehicle anti-lock brake control apparatus having wheel speed sensor for detecting actual speed of a vehicle wheel, solenoid-operated valve for regulating the wheel braking pressure, and controller for controlling the valve, on the basis of the detected actual speed, and vehicle ground-speed detected by ground-speed sensor. The controller controls the valve at a controlled duty cycle, which is determined on the basis of at least a wheel speed error and a time derivative of this error. The error is obtained as a deviation of the detected actual wheel speed from a target wheel speed obtained on the basis of the detected vehicle ground-speed.
Inventors
- 👤 Shinji Ikeda
- 👤 Masashi Mizukoshi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 06:03
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/17; B60T8/176; B60T8/1763; B60T8/17636; B60T8/173; B60T8/1761; B60T8/17616
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
128 words
A Doppler-effect type ground-speed sensor including a transmitter attached to a body of the vehicle and transmitting a wave toward a road surface in a predetermined direction of propagation, a receiver attached to said body and receiving a portion of said wave which is irregularly reflected by said road surface, and a signal processor which provides an output representative of said ground-speed of the vehicle, on the basis of frequencies of said wave transmitted by said transmitter and said portion received by said receiver, wherein the improvement comprises: said receiver is spaced apart from said transmitter by a predetermined distance in one of opposite running directions of the vehicle in which said predetermined direction of propagation is inclined with respect to a direction perpendicular to the running directions.
Claim 2
Dependent Claim
128 words
A Doppler-effect type ground-speed sensor including a transmitter attached to a body of the vehicle and transmitting a wave toward a road surface in a predetermined direction of propagation, a receiver attached to said body and receiving a portion of said wave which is irregularly reflected by said road surface, and a signal processor which provides an output representative of said ground-speed of the vehicle, on the basis of frequencies of said wave transmitted by said transmitter and said portion received by said receiver, wherein the improvement comprises: said receiver is spaced apart from said transmitter by a predetermined distance in one of opposite running directions of the vehicle in which said predetermined direction of propagation is inclined with respect to a direction perpendicular to the running directions.
Claim 3
Dependent Claim
16 words
The Doppler-effect type ground-speed sensor according to claim 1, wherein said transmitter generates a ultrasonic wave.
Claim 4
Dependent Claim
51 words
The Doppler-effect type ground-speed sensor according to claim 1, wherein said direction of propagation of said wave transmitted by said transmitter is inclined in a forward running direction of the vehicle as said one of opposite running directions, said receiver being spaced apart from said transmitter in said forward running direction.
Claim 5
Dependent Claim
52 words
The Doppler-effect type ground-speed sensor according to claim 1, wherein said direction of propagation of said wave transmitted by said transmitter is inclined in a backward running direction of the vehicle as said one of opposite running directions, and said receiver being spaced apart from said transmitter in said backward running direction.
Claim 6
Dependent Claim
21 words
The Doppler-effect type ground-speed sensor according to claim 1, wherein said predetermined distance is a function of a selected vehicle speed.
Claim 7
Dependent Claim
48 words
The Doppler-effect type ground-speed sensor according to claim 1, wherein said predetermined distance is equal to the distance moved by said vehicle at a selected vehicle speed while said wave transmitted by said transmitter is reflected by said road surface and said portion is received by said receiver.
Claim 8
Dependent Claim
32 words
The Doppler-effect type ground-speed sensor according to claim 4, wherein said receiver has an optical axis parallel to an optical axis of said transmitter which is parallel to said direction of propagation.
References Cited (Backward Citations)
US4346774A
Cited
US4432229A
Cited
US4713665A
Cited
JPS6364861A
Cited
US4932726A
Cited
US4900101A
Cited
JPH0270561A
Cited
DE3825639A1
Cited
JPH02129960A
Cited
US5204682A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1997-08-01 | 1998-01-31 | 1998-08-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-08-01 | 2002-01-31 | 2002-08-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-08-01 | 2006-01-31 | 2006-08-02 | $7700.00 | Window Closed / Lapsed |