US3741043A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wheel spin control system for automatic transmissions
Assignee: Toyota Motor Corp
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Filing: 1972-04-05
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Granted: 1973-06-26
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Expires: 1992-04-05
Abstract
Abstract In a vehicle transmission of the type in which the torque is transmitted between the drive shaft and the driven shaft, a control system for an automatic transmission comprising a gear shift engagement unit including engaging means with hydraulic servos, a source of fluid pressure for generating fluid pressure for said hydraulic servos, shift valves adapted to distribute the fluid pressure to said hydraulic servos, driven-wheel speedresponsive signal generating means, engine torque-responsive signal generating means, vehicle speed-responsive signal generating means, shift discriminating circuits each for receiving and performing computational operations on the signals from said signal generating means, and a speed ratio discriminating circuit for receiving said driven-wheel speedresponsive signal and said vehicle speed-responsive signal to compute the slip factor of the driven wheel, whereby said shift valves are selectively controlled according to the output signals from said shift discriminating circuits and said speed ratio discriminating circuit to thereby reduce the transmission of the torque between the transmission input or drive shaft connected to the engine and the transmission output or driven shaft which connects to the driven wheels when they begin to spin at low speeds due to slippery conditions.
Inventors
- 👤 M Oya
- 👤 S Ito
- 👤 S Kubo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 07:34
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/02; F16H61/0202; F16H61/0204; F16H61/0213; F16H59/00; F16H59/50; F16H2059/506; F16H2061/0234; F16H2061/0239; F16H59/60; F16H59/66
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
262 words
A wheel spin control system for an automatic transmission used in a road vehicle having at least one wheel driven by an engine, said transmission being capable of establishing between said engine and driven wheel any one of a plurality of different driving gear ratios including at least a low speed gear ratio and a higher speed gear ratio when shifted thereinto, said control system comprising: means connected to said vehicle for providing a first electrical signal representing the speed of said driven wheel, means connected to said vehicle for providing a second electrical signal representing the road speed of said vehicle, shifting means connected to one of said providing means and responsive at least to the said speed representative electrical signal provided thereby and connected to said transmission for automatically shifting said transmission from one to another of said driving gear ratios based upon certain conditions including the said speed represented by the electrical signal received by said shifting means from said one providing means, means connected to both said providing means and responsive to said first and second electrical signals for developing a given electrical output only when said driven wheel speed exceeds said vehicle road speed by a predetermined amount and, means operatively connected to said developing means and said shifting means for causing automatic upsHifting thereby from said low speed gear ratio to said higher speed gear ratio only when said given output appears at least during a given range of driven wheel speeds, to reduce transmission output torque on and consequently rotational slipping of said driven wheel.
Claim 2
Dependent Claim
262 words
A wheel spin control system for an automatic transmission used in a road vehicle having at least one wheel driven by an engine, said transmission being capable of establishing between said engine and driven wheel any one of a plurality of different driving gear ratios including at least a low speed gear ratio and a higher speed gear ratio when shifted thereinto, said control system comprising: means connected to said vehicle for providing a first electrical signal representing the speed of said driven wheel, means connected to said vehicle for providing a second electrical signal representing the road speed of said vehicle, shifting means connected to one of said providing means and responsive at least to the said speed representative electrical signal provided thereby and connected to said transmission for automatically shifting said transmission from one to another of said driving gear ratios based upon certain conditions including the said speed represented by the electrical signal received by said shifting means from said one providing means, means connected to both said providing means and responsive to said first and second electrical signals for developing a given electrical output only when said driven wheel speed exceeds said vehicle road speed by a predetermined amount and, means operatively connected to said developing means and said shifting means for causing automatic upsHifting thereby from said low speed gear ratio to said higher speed gear ratio only when said given output appears at least during a given range of driven wheel speeds, to reduce transmission output torque on and consequently rotational slipping of said driven wheel.
Claim 3
Dependent Claim
70 words
A control system as in claim 1 including means establishing at least an upper limit of said given range of driven wheel speeds for providing a second given electrical output when the driven wheel speed is less than said upper limit, and means operatively connecting said upper limit establishing means to said automatic upshifting means to cause upshifting thereby only when at least both of said given electrical outputs coexist.
Claim 4
Dependent Claim
69 words
A control system as in claim 1 including means establishing at least a lower limit of said given range of driven wheel speeds for producing a second given electrical output only when the driven wheel speed exceeds said lower limit, and means operatively connecting said lower limit establishing means to said automatic upshifting means to cause upshifting thereby only if at least both of said given electrical outputs coexist.
Claim 5
Dependent Claim
163 words
A control system as in claim 3 for use with a transmission of the type which has not only the aforesaid low and higher speed gear ratios but also an intermediate speed gear ratio, comprising: means for establishing a third electrical signal representing the upper speed limit of said given range of driven wheel speeds, said upper speed limit being below that which can cause said shifting means to automatically shift from said low speed gear ratio to said intermediate speed gear ratio, means connected to said upper speed limit establishing means and to said first electrical signal providing means for comparing the said signals therefrom to cause a third given electrical output only when said driven wheel speed is less than said upper limit speed, and means operatively connecting said comparing means to said automatic upshifting means to cause upshifting thereby from said low speed gear ratio to said higher gear ratio only when all three of said given electrical outputs coexist.
Claim 6
Dependent Claim
119 words
A control system as in claim 1 wherein said shifting means includes solenoid means and, connected thereto, means for developing a shift signal in response to at least the said speed representative electrical signal supplied by said one providing means for energizing said solenoid means by said shifting signal to cause shifting from said low speed gear ratio to said higher speed gear ratio when said certain conditions occur, said upshifting means including means connected between said solenoid means and said shift signal developing means and responsive to the said given electrical output from the latter for preventing said shift signal from energizing said solenoid means at least when the said driven wheel speed is in said given range.
Claim 7
Dependent Claim
27 words
A control system as in claim 1 wherein said one providing means is the one which supplies first electrical signal representing the speed of said driven wheel.
Claim 8
Dependent Claim
47 words
A control system as in claim 6 including means adapted to be connected to said engine for providing a third electrical signal representing engine load and means operatively connecting said third signal to said shifting means to cause said certain conditions to also include engine throttle position.
Claim 9
Dependent Claim
215 words
In an automatic transmission control system for use in a vehicle to reduce the spin of a wheel driven on a slippery road surface by the torque developed by an engine and transmitted to said driven wheel by an automatic transmission having a gearing unit capable of establishing between said engine and wheel any one of a plurality of forward driving gear ratios, including at least a low speed gear ratio and a high speed gear ratio, when shifted thereinto, the improvement comprising: automatic transmission shifting means connected to said transmission and vehicle for automatically shifting said transmission from one to another of said driving geAr ratio based upon certain vehicle conditions means connected to said vehicle for producing a given electrical output signal only when the spin of said driven wheel exceeds a predetermined amount because of excessive rotational slippage of the driven wheel on said road surface, and means operatively connected to said producing means and said automatic shifting means for causing said transmission when it is automatically in said low gear ratio as aforesaid to be automatically upshifted from said low gear ratio to said high gear ratio when said given electrical output signal occurs, for reducing the engine torque on said driven wheel and hence the said excessive rotational slippage thereof.
Claim 10
Dependent Claim
215 words
In an automatic transmission control system for use in a vehicle to reduce the spin of a wheel driven on a slippery road surface by the torque developed by an engine and transmitted to said driven wheel by an automatic transmission having a gearing unit capable of establishing between said engine and wheel any one of a plurality of forward driving gear ratios, including at least a low speed gear ratio and a high speed gear ratio, when shifted thereinto, the improvement comprising: automatic transmission shifting means connected to said transmission and vehicle for automatically shifting said transmission from one to another of said driving geAr ratio based upon certain vehicle conditions means connected to said vehicle for producing a given electrical output signal only when the spin of said driven wheel exceeds a predetermined amount because of excessive rotational slippage of the driven wheel on said road surface, and means operatively connected to said producing means and said automatic shifting means for causing said transmission when it is automatically in said low gear ratio as aforesaid to be automatically upshifted from said low gear ratio to said high gear ratio when said given electrical output signal occurs, for reducing the engine torque on said driven wheel and hence the said excessive rotational slippage thereof.
Claim 11
Dependent Claim
219 words
In an automatic transmission control system for use in a vehicle to reduce the spin of a wheel driven on a slippery road surface by the torque developed by an engine and transmitted to said driven wheel by an automatic transmission having a gearing unit capable of establishing between said engine and wheel any one of a plurality of forward driving gear ratios, including at least a low speed gear ratio and a high speed gear ratio, when shifted thereinto, the improvement comprising: automatic transmission shifting means adapted to be connected to said transmission and vehicle for automatically shifting said transmission from one to another of said driving gear ratios based upon certain vehicle conditions, means connected to said vehicle for producing a given electrical output signal only when said driven wheel spins on a said slippery road surface in a given speed range with its rotational slippage exceeding a predetermined amount, and means operatively connected to said producing means and said automatic shifting means for causing said transmission when it is automatically in said low gear ratio as aforesaid to be automatically upshifted from said low gear ratio to said high gear ratio when said given electrical output signal occurs, for reducing the transmission output torque on said driven wheel and hence the said excessive rotational slippage thereof.
Claim 12
Dependent Claim
219 words
In an automatic transmission control system for use in a vehicle to reduce the spin of a wheel driven on a slippery road surface by the torque developed by an engine and transmitted to said driven wheel by an automatic transmission having a gearing unit capable of establishing between said engine and wheel any one of a plurality of forward driving gear ratios, including at least a low speed gear ratio and a high speed gear ratio, when shifted thereinto, the improvement comprising: automatic transmission shifting means adapted to be connected to said transmission and vehicle for automatically shifting said transmission from one to another of said driving gear ratios based upon certain vehicle conditions, means connected to said vehicle for producing a given electrical output signal only when said driven wheel spins on a said slippery road surface in a given speed range with its rotational slippage exceeding a predetermined amount, and means operatively connected to said producing means and said automatic shifting means for causing said transmission when it is automatically in said low gear ratio as aforesaid to be automatically upshifted from said low gear ratio to said high gear ratio when said given electrical output signal occurs, for reducing the transmission output torque on said driven wheel and hence the said excessive rotational slippage thereof.
Claim 13
Dependent Claim
209 words
In a transmission control system for use in a vehicle to reduce the spin of a wheel driven on a slippery road surface by the torque developed by an engine and transmitted to said driven wheel by a transmission having a gearing unit capable of establishing between said engine and wheel any one of a plurality of forward driving gear ratios, including at least a lower speed gear ratio and a higher speed gear ratio, and having the improvement comprising: shifting means connected to said transmission and vehicle for shifting said transmission from one to another of said driving gear ratios, wheel spin sensing means connected to said vehicle for producing a given electrical output signal only when the spin of said driven wheel exceeds a predetermined amount because of excessive rotational slippage of the driven wheel on said road surface, and automatic upshift means operatively connected to said sensing-producing means and operatively connected to said automatic shifting means for causing said transmission when it in said lower gear ratio to be automatically upshifted from said lower gear ratio to said higher gear ratio when said given electrical output signal occurs, for reducing the transmission output torque on said driven wheel and hence the said excessive rotational slippage thereof.
Claim 14
Dependent Claim
209 words
In a transmission control system for use in a vehicle to reduce the spin of a wheel driven on a slippery road surface by the torque developed by an engine and transmitted to said driven wheel by a transmission having a gearing unit capable of establishing between said engine and wheel any one of a plurality of forward driving gear ratios, including at least a lower speed gear ratio and a higher speed gear ratio, and having the improvement comprising: shifting means connected to said transmission and vehicle for shifting said transmission from one to another of said driving gear ratios, wheel spin sensing means connected to said vehicle for producing a given electrical output signal only when the spin of said driven wheel exceeds a predetermined amount because of excessive rotational slippage of the driven wheel on said road surface, and automatic upshift means operatively connected to said sensing-producing means and operatively connected to said automatic shifting means for causing said transmission when it in said lower gear ratio to be automatically upshifted from said lower gear ratio to said higher gear ratio when said given electrical output signal occurs, for reducing the transmission output torque on said driven wheel and hence the said excessive rotational slippage thereof.
Claim 15
Dependent Claim
268 words
In an automatic transmission control system for use in a vehicle to reduce the spin of a wheel driven on a slippery road surface by the torque developed by an engine and transmitted to said driven wheel by an automatic transmission having a gearing unit capable of establishing between said engine and wheel any one of a plurality of forward driving gear ratios, including at least a relatively low speed gear ratio and a relatively high speed gear ratio, when shifted thereinto, the improvement comprising: automatic transmission shifting means connected to said transmission and vehicle for automaticallY shifting said transmission from one to another of said driving gear ratios based upon certain vehicle conditions, multiple position manual shifting means operatively connected to said automatic shifting means and adapted to be connected to said transmission for manually establishing said transmission in at least said low speed forward gear or in an automatic position for causing said automatic shifting means to effect automatic shifting as aforesaid, means connected to said vehicle for producing a given electrical output signal only when said driven wheel spins on said slippery road surface in a given speed range with its rotational slippage exceeding a predetermined amount, and means operatively connected to said producing means and to one of said shifting means for causing said transmission when it is in said low gear ratio as aforesaid to be automatically upshifted from said low gear ratio to said high gear ratio when said given electrical output signal occurs, for reducing the transmission output torque on said driven wheel and hence the said excessive rotational slippage thereof.
Claim 16
Dependent Claim
268 words
In an automatic transmission control system for use in a vehicle to reduce the spin of a wheel driven on a slippery road surface by the torque developed by an engine and transmitted to said driven wheel by an automatic transmission having a gearing unit capable of establishing between said engine and wheel any one of a plurality of forward driving gear ratios, including at least a relatively low speed gear ratio and a relatively high speed gear ratio, when shifted thereinto, the improvement comprising: automatic transmission shifting means connected to said transmission and vehicle for automaticallY shifting said transmission from one to another of said driving gear ratios based upon certain vehicle conditions, multiple position manual shifting means operatively connected to said automatic shifting means and adapted to be connected to said transmission for manually establishing said transmission in at least said low speed forward gear or in an automatic position for causing said automatic shifting means to effect automatic shifting as aforesaid, means connected to said vehicle for producing a given electrical output signal only when said driven wheel spins on said slippery road surface in a given speed range with its rotational slippage exceeding a predetermined amount, and means operatively connected to said producing means and to one of said shifting means for causing said transmission when it is in said low gear ratio as aforesaid to be automatically upshifted from said low gear ratio to said high gear ratio when said given electrical output signal occurs, for reducing the transmission output torque on said driven wheel and hence the said excessive rotational slippage thereof.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-25 | 1976-12-25 | 1977-06-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-25 | 1980-12-25 | 1981-06-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-25 | 1984-12-25 | 1985-06-26 | $7700.00 | Window Closed / Lapsed |