US3922022A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Skid control braking system
Assignee: Toyota Motor Corp
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Filing: 1974-01-14
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Granted: 1975-11-25
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Expires: 1994-01-14
Abstract
Abstract A modulator modulates the brake forces that a brake system applies to a number of a vehicle''s wheels, on the basis of a control signal. The latter is derived in part by sensing the wheels'' speeds to generate composite wheel speed signals and by generating reference signals which respond to the composite signals but which are variable at a slower rate than the composite signals. The control signal is finally derived by combining the difference between the composite and reference signals and the difference between the respective differentials of the composite and reference signals. A modulation rate regulator responds to the control signals to change the rate at which the control signal modulates the brake forces on the basis of the control signal. According to an embodiment the system operates with the front wheels and a second similar system with a second modulator and control signal operates upon the rear wheels. A common reference signal is formed from the speeds of all the wheels.
Inventors
- 👤 Takeshi Ochiai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:35
CPC Classifications
B; B60; B60T; B60T8/00; B60T8/32; B60T8/34; B60T8/50; B60T8/5087; B60T8/5093; B60T8/17; B60T8/176; B60T8/1764; B60T8/343; B60T8/344; B60T8/346; B60T8/5018; B60T8/5025; B60T8/5037; B60T8/5043
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
196 words
An apparatus for modulating the brake force applied to the brakes of wheels of a vehicle, comprising: sensor means coupled to the wheels for forming wheel speed signals corresponding to the speeds of the wheels; circuit means coupled to said sensor means for establishing a wheel speed composite signal representing a composite of the speeds of the wheels and a reference signal derived from the speeds of the wheels and variable at a rate slower than the composite signal; control signal forming means coupled to said circuit means for producing a control signal representing a sum of a value proportional to both the positive and negative difference between the composite signal and the reference signal and a value proportional to both the positive and negative difference between the differential of the composite signal and the differential of the reference signal; modulating means responsive to said forming means for changing the force on the basis of the control signal; and modulation speed regulating means responsive to said forming means and coupled to said modulating means for varying the rate at which the modulating means modulates the force on the basis of the magnitude of the control signal.
Claim 2
Independent Claim
196 words
An apparatus for modulating the brake force applied to the brakes of wheels of a vehicle, comprising: sensor means coupled to the wheels for forming wheel speed signals corresponding to the speeds of the wheels; circuit means coupled to said sensor means for establishing a wheel speed composite signal representing a composite of the speeds of the wheels and a reference signal derived from the speeds of the wheels and variable at a rate slower than the composite signal; control signal forming means coupled to said circuit means for producing a control signal representing a sum of a value proportional to both the positive and negative difference between the composite signal and the reference signal and a value proportional to both the positive and negative difference between the differential of the composite signal and the differential of the reference signal; modulating means responsive to said forming means for changing the force on the basis of the control signal; and modulation speed regulating means responsive to said forming means and coupled to said modulating means for varying the rate at which the modulating means modulates the force on the basis of the magnitude of the control signal.
Claim 3
Dependent Claim
172 words
An apparatus as in claim 1, wherein the vehicle includes other wheels and said sensor means are coupled to the other wheels for forming second wheel speed signals corresponding to the speeds of the other wheels; said circuit means including means for establishing a second wheel speed composite signal representing a composite of the speeds of the other wheels and deriving the reference signal from the speeds of all the wheels; said control signal means including means for producing a second control signal representing a combination of the difference between the second composite signal and the reference signal and the difference between the differential of the second composite signal and the differential of the reference signal; said modulating means including means for changing the braking force in the other wheels on the basis of the second control signal; and said regulating means including means for varying the rate at which the modulating means modulates the brake force on the other wheels on the basis of the magnitude of the second control signal.
Claim 4
Dependent Claim
28 words
An apparatus as in claim 2, wherein the first wheels of the vehicle are the front wheels and the second wheels of the vehicle are the rear wheels.
Claim 5
Dependent Claim
22 words
An apparatus as in claim 2, wherein said composite forming means selects the maximum wheel velocity of all the wheel velocity signals.
Claim 6
Dependent Claim
84 words
An apparatus as in claim 2, wherein said forming means includes first difference circuit means responsive to said composite signal and said reference signal for producing the difference between said composite signal and said reference signal; first differential circuit means for producing the differential of said composite signal; second differential circuit means for producing the differential of said reference signal; and second difference circuit means coupled to said first and second differential circuit means for producing the difference between the output of the differential.
Claim 7
Dependent Claim
58 words
An apparatus as in claim 2, wherein said modulation speed regulating means includes means for causing said modulating means to change the force at a first rate when the control signal has a value less than a predetermined absolute value and for changing the force at a second rate when the control signal exceeds the predetermined absolute value.
Claim 8
Dependent Claim
80 words
An apparatus as in claim 2, wherein said modulating means includes a discriminator to determine whether the value of the control signal is positive or negative; an electromagnet responsive to the discriminator; valve means responsive to said electromagnet for varying the pressure; second valve means for varying the rate at which said first valve means changes the pressure; and electromagnetic means coupled to said control signal forming means and responsive to the control signal for controlling said second valve means.
Claim 9
Dependent Claim
102 words
An apparatus as in claim 7, wherein said circuit means includes brake signal means responsive to the brake for indicating that the brake is being operated and low speed sensing means responsive to the composite signal for producing a low speed signal; said circuit means including gate means coupled to said brake indicator and said low speed sensing means and coupled to said electromagnet and electromagnetic means for disabling said electromagnet and said electromagnetic means unless the low speed sensing means and said indicating means produce signals indicating that the brake is being operated and the speed is below a predetermined value.
Claim 10
Dependent Claim
21 words
An apparatus as in claim 2, wherein said composite forming means selects the minimum wheel velocity of the wheel velocity signals.
Claim 11
Dependent Claim
20 words
An apparatus as in claim 2, wherein said composite forming means selects the arithmetic means of the wheel velocity signal.
Claim 12
Dependent Claim
20 words
An apparatus as in claim 2, wherein said composite forming means selects the geometric means of the wheel velocity signal.
Claim 13
Dependent Claim
62 words
An apparatus as in claim 1, wherein said circuit means includes composite signal forming means coupled to said sensor means and reference signal forming means coupled to said composite signal forming means; said reference signal forming means including memory means responsive to said composite signal forming means for causing the reference signal to vary at a rate slower than the composite signal.
Claim 14
Dependent Claim
170 words
An apparatus as in claim 12, wherein the vehicle includes other wheels and said sensor means are coupled to the other wheels for forming second wheel speed signals corresponding to the speeds of the other wheels; said circuit means including means for establishing a second composite signal representing a composite of the speeds of the other wheels and forming the reference signal from the speeds of all the wheels; said control signal means including means for producing a second control signal representing a combination of the difference between the second composite signal and the reference signal and the difference between the differential of the second composite signal and the differential of the reference signal; said modulating means including means for changing the braking force in the other wheels on the basis of the second control signal; and said regulating means including means for varying the rate at which the modulating means modulates the brake force on the other wheels on the basis of the magnitude of the second control signal.
Claim 15
Dependent Claim
26 words
An apparatus as in claim 13, wherein said composite signal forming means includes means for selecting the maximum wheel velocity of all the wheel velocity signals.
Claim 16
Dependent Claim
39 words
An apparatus as in claim 12, wherein said reference signal forming means includes factor means for multiplying the output of said memory means by a predetermined fraction representing a desired ratio between a wheel velocity and a vehicle velocity.
Claim 17
Dependent Claim
170 words
An apparatus as in claim 15, wherein the vehicle includes other wheels and said sensor means are coupled to the other wheels for forming second wheel speed signals corresponding to the speeds of the other wheels; said circuit means including means for establishing a second composite signal representing a composite of the speeds of the other wheels and forming the reference signal from the speeds of all the wheels; said control signal means including means for producing a second control signal representing a combination of the difference between the second composite signal and the reference signal and the difference between the differential of the second composite signal and the differential of the reference signal; said modulating means including means for changing the braking force in the other wheels on the basis of the second control signal; and said regulating means including means for varying the rate at which The modulating means modulates the brake force on the other wheels on the basis of the magnitude of the second control signal.
Claim 18
Dependent Claim
26 words
An apparatus as in claim 16, wherein said composite signal forming means includes means for selecting the maximum wheel velocity of all the wheel velocity signals.
Claim 19
Dependent Claim
26 words
An apparatus as in claim 15, wherein said composite signal forming means includes means for selecting the maximum wheel velocity of all the wheel velocity signals.
Claim 20
Dependent Claim
84 words
An apparatus as in claim 15, wherein said forming means includes first difference circuit means responsive to said composite signal and said reference signal for producing the difference between said composite signal and said reference signal; first differential circuit means for producing the differential of said composite signal; second differential circuit means for producing the differential of said reference signal; and second difference circuit means coupled to said first and second differential circuit means for producing the difference between the output of the differentials.
Claim 21
Dependent Claim
26 words
An apparatus as in claim 12, wherein said composite signal forming means includes means for selecting the maximum wheel velocity of all the wheel velocity signals.
Claim 22
Dependent Claim
84 words
An apparatus as in claim 20, wherein said forming means includes first difference circuit means responsive to said composite signal and said reference signal for producing the difference between said composite signal and said reference signal; first differential circuit means for producing the differential of said composite signal; second differential circuit means for producing the differential of said reference signal; and second difference circuit means coupled to said first and second differential circuit means for producing the difference between the output of the differentials.
Claim 23
Dependent Claim
58 words
An apparatus as in claim 20, wherein said modulation speed regulating means includes means for causing said modulating means to change the force at a first rate when the control signal has a value less than a predetermined absolute value and for changing the force at a second rate when the control signal exceeds the predetermined absolute value.
Claim 24
Dependent Claim
84 words
An apparatus as in claim 12, wherein said forming means includes first difference circuit means responsive to said composite signal and said reference signal for producing the difference between said composite signal and said reference signal; first differential circuit means for producing the differential of said composite signal; second differential circuit means for producing the differential of said reference signal; and second difference circuit means coupled to said first and second differentail circuit means for producing the difference between the output of the differentials.
Claim 25
Dependent Claim
58 words
An apparatus as in claim 12, wherein said modulation speed regulating means includes means for causing said modulating means to change the force at a first rate when the control signal has a value less than a predetermined absolute value and for changing the force at a second rate when the control signal exceeds the predetermined absolute value.
Claim 26
Dependent Claim
101 words
An apparatus as in claim 1, wherein said circuit means including selector means for extracting the maximum one of the wheel speeds W; said circuit means including means for generating a signal Wm from the maximum one of the wheel speeds, memory means responsive to the signal Wm for producing a signal Vo slower than Wm, and factor setting means for producing the reference signal Vt at a value between 0.8 to 0.85 Vo; said control signal forming means including computational means for producing a value Sf A1(Vt - W) + A2(Vt'' - W''), wherein A1 and A2 are predetermined factors.
Claim 27
Dependent Claim
26 words
An apparatus as in claim 25, wherein saiD composite signal forming means includes means for selecting the maximum wheel velocity of all the wheel velocity signals.
Claim 28
Dependent Claim
84 words
An apparatus as in claim 26 wherein said forming means includes first difference circuit means responsive to said composite signal and said reference signal for producing the difference between said composite signal and said reference signal; first differential circuit means for producing the differential of said composite signal; second differential circuit means for producing the differential of said reference signal; and second difference circuit means coupled to said first and second differential circuit means for producing the difference between the output of the differentials.
Claim 29
Dependent Claim
58 words
An apparatus as in claim 27, wherein said modulation speed regulating means includes means for causing said modulating means to change the force at a first rate when the control signal has a value less than a predetermined absolute value and for changing the force at a second rate when the control signal exceeds the predetermined absolute value.
Claim 30
Dependent Claim
80 words
An apparatus as in claim 28, wherein said modulating means includes a discriminator to determine whether the value of the control signal is positive or negative; an electromagnet responsive to the discriminator; valve means responsive to said electromagnet for varying the pressure; second valve means for varying the rate at which said first valve means changes the pressure; and electromagnetic means coupled to said control signal forming means and responsive to the control signal for controlling said second valve means.
Claim 31
Dependent Claim
58 words
An apparatus as in claim 26, wherein said modulation speed regulating means includes means for causing said modulating means to change the force at a first rate when the control signal has a value less than a predetermined absolute value and for changing the force at a second rate when the control signal exceeds the predetermined absolute value.
Claim 32
Dependent Claim
84 words
An apparatus as in claim 25, wherein said forming means includes first difference circuit means responsive to said composite signal and said reference signal for producing the difference between said composite signal and said reference signal; first differential circuit means for producing the differential of said composite signal; second differential circuit means for producing the differential of said reference signal; and second difference circuit means coupled to said first and second differential circuit means for producing the difference between the output of the differentials.
Claim 33
Dependent Claim
58 words
An apparatus as in claim 25, wherein said modulation speed regulating means includes means for causing said modulating means to change the force at a first rate when the control signal has a value less than a predetermined absolute value and for changing the force at a second rate when the control signal exceeds the predetermined absolute value.
Claim 34
Dependent Claim
84 words
An apparatus as in claim 1, wherein said forming means includes first difference circuit means responsive to said composite signal and said reference signal for producing the difference between said composite signal and said reference signal; first differential circuit means for producing the differential of said composite signal; second differential circuit means for producing the differential of said reference signal; and second difference circuit means coupled to said first and second differential circuit means for producing the difference between the output of the differentials.
Claim 35
Dependent Claim
58 words
An apparatus as in claim 33, wherein said modulation speed regulating means includes means for causing said modulating means to change the force at a first rate when the control signal has a value less than a predetermined absolute value and for changing the force at a second rate when the control signal exceeds the predetermined absolute value.
Claim 36
Dependent Claim
58 words
An apparatus as in claim 1, wherein said modulation speed regulating meAns includes means for causing said modulating means to change the force at a first rate when the control signal has a value less than a predetermined absolute value and for changing the force at a second rate when the control signal exceeds the predetermined absolute value.
Claim 37
Dependent Claim
80 words
An apparatus as in claim 1, wherein said modulating means includes a discriminator to determine whether the value of the control signal is positive or negative; an electromagnet responsive to the discriminator; valve means responsive to said electromagnet for varying the pressure; second valve means for varying the rate at which said first valve means changes the pressure; and electromagnetic means coupled to said control signal forming means and responsive to the control signal for controlling said second valve means.
Claim 38
Dependent Claim
111 words
An apparatus as in claim 36, wherein said electromagnetic means includes double threshold forming means for forming two thresholds responsive to said control signal and for producing a first determining signal when the control signal is between the thresholds and a second signal when the control signal is outside the threshold; said electromagnetic means including an electromagnet responsive to said threshold means; said second valve means being movable by said electromagnetic means between a first position wherein the change of pressure is at a first level in response to the first determining signal and the change of pressure is at a less rapid level in response to a second determining signal.
Claim 39
Dependent Claim
100 words
An apparatus as in claim 1, wherein said circuit means including selector means for extracting the lower of the wheel speeds W; said circuit means including means for generating a signal Wm from the minimum of the wheel speeds, memory means responsive to the signal Wm for producing a signal Vo slower than Wm, and factor sensing means for producing the reference signal Vt at a value between 0.8 to 0.85 Vo; said control signal forming means including computational means for producing a value Sf A1 (Vt - W) + A2(Vt'' - W''), where A1 and A2 are predetermined factors.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-24 | 1979-05-26 | 1979-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-24 | 1983-05-26 | 1983-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-24 | 1987-05-26 | 1987-11-25 | $7700.00 | Window Closed / Lapsed |