US3868869A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic transmission control systems
Assignee: Associated Engineering Ltd
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Filing: 1973-01-08
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Granted: 1975-03-04
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Expires: 1993-01-08
Abstract
Abstract The invention relates to a system for controlling an automatic transmission of a road vehicle. The system includes a valve member movable between first and second positions, at one of which positions the valve member allows pressurised fluid to pass to operate a friction-engaging element of the transmission in one direction, and at the other position the valve member vents the fluid to operate the friction-engaging element in the opposite direction. The valve member is moved in at least one direction by the application of pressurised fluid controlled by an electrically-operated solenoid valve. The invention also relates to the particular electrical operation of the solenoid valve.
Inventors
- 👤 Norman Hunt
- 👤 John Noddings
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 21:08
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/02; F16H61/0202; F16H61/0204; F16H61/0206; F16H61/0211; F16H47/00; F16H47/06; F16H47/08; F16H61/04; F16H61/06; F16H61/061; F16H61/0251; F16H2061/0255; Y; Y10; Y10S; Y10S477/00; Y10S477/906
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
279 words
For an automatic transmission including a frictionengaging element operable to change the drive ratio of the transmission, and a supply of pressurized fluid connected to the frictionengaging element, the friction-engaging element being actuated to effect a ratio change in dependence upon the supply of fluid thereto from said supply, a control system including a fluidpressure actuated fluid-control valve having a valve housing, a cavity in said valve housing, a valve member located in said housing and movable therein, and fluid passage means connectable to said friction-engaging element and pressurized fluid supply, said valve member being movable within with cavity between first and second positions, at one of which positions the valve member allows pressurized fluid to pass through said passage means to operate the friction-engaging element of the transmission in one direction, and at the other position the valve member vents the fluid to operate the friction-engaging element in the opposite direction, the control system further including an electrical solenoid-operated fluid-control valve for actuating said fluidpressure actuated valve, fluid passage means connecting said solenoid-operated valve to the cavity of said fluid-pressure actuated valve, said solenoid-operated valve being operable to modify the pressure of pressurized fluid acting on said movable valve member, thereby to move the valve member in at least one direction, and electrical circuit means connected to the solenoid of said solenoid-operated valve to actuate the latter, said circuit being operable to supply a train of electrical pulses to said solenoid for a period after initiation of a change of drive ratio, the circuit means being adapted to vary at least one characteristic of the pulses in the train in dependence upon at least one variable operating parameter.
Claim 2
Dependent Claim
279 words
For an automatic transmission including a frictionengaging element operable to change the drive ratio of the transmission, and a supply of pressurized fluid connected to the frictionengaging element, the friction-engaging element being actuated to effect a ratio change in dependence upon the supply of fluid thereto from said supply, a control system including a fluidpressure actuated fluid-control valve having a valve housing, a cavity in said valve housing, a valve member located in said housing and movable therein, and fluid passage means connectable to said friction-engaging element and pressurized fluid supply, said valve member being movable within with cavity between first and second positions, at one of which positions the valve member allows pressurized fluid to pass through said passage means to operate the friction-engaging element of the transmission in one direction, and at the other position the valve member vents the fluid to operate the friction-engaging element in the opposite direction, the control system further including an electrical solenoid-operated fluid-control valve for actuating said fluidpressure actuated valve, fluid passage means connecting said solenoid-operated valve to the cavity of said fluid-pressure actuated valve, said solenoid-operated valve being operable to modify the pressure of pressurized fluid acting on said movable valve member, thereby to move the valve member in at least one direction, and electrical circuit means connected to the solenoid of said solenoid-operated valve to actuate the latter, said circuit being operable to supply a train of electrical pulses to said solenoid for a period after initiation of a change of drive ratio, the circuit means being adapted to vary at least one characteristic of the pulses in the train in dependence upon at least one variable operating parameter.
Claim 3
Dependent Claim
19 words
A system according to claim 1, wherein the valve member is moved in the other direction by a spring.
Claim 4
Dependent Claim
29 words
A system according to claim 2, wherein two valve members are provided, biased apart to opposite ends of their travel by the spring which acts upon both valve members.
Claim 5
Dependent Claim
34 words
A system according to claim 3, wherein at least one of the valve members is moved by fluid pressure, when its respective solenoid valve passes pressurised fluid, into abutment with the other valve member.
Claim 6
Dependent Claim
48 words
A system according to claim 4, wherein the or each valve member is a spool valve, slidable in a bore, and having at least two cylindrical sealing lands with an intermediate waisted portion, thereby to open and close at least one port in the wall of the bore.
Claim 7
Dependent Claim
33 words
A system according to claim 5, wherein the or each valve member is divided transversely into two portions kept in abutment, thereby to accommodate slight irregularity in the bore or the valve member.
Claim 8
Dependent Claim
46 words
A system according to claim 6, wherein at least one of the sealing lands has a tapered portion joining the, or each, cylindricAl land to the waisted portion, thereby to reduce the rate at which the port is closed or opened as the valve member moves.
Claim 9
Dependent Claim
139 words
For an automatic transmission including a frictionengaging element operable to change the drive ratio of the transmission, and a fluid supply connected to the friction-engaging element, the friction-engaging element being actuated to effect a ratio change in dependence upon the supply of fluid thereto from said fluid supply, a control system including a solenoid-operated fluid-control valve operable to control the supply of fluid for operating the friction-engaging element of the transmission and thereby actuate the friction-engaging element to effect changes of drive ratio, and electrical circuit means connected to the solenoid valve and operable to supply a train of electrical pulses to the solenoid valve for a period after initiation of a change of drive ratio, at least one characteristic of the pulses in the train being variable in dependence upon variations in at least one variable operating parameter.
Claim 10
Dependent Claim
139 words
For an automatic transmission including a frictionengaging element operable to change the drive ratio of the transmission, and a fluid supply connected to the friction-engaging element, the friction-engaging element being actuated to effect a ratio change in dependence upon the supply of fluid thereto from said fluid supply, a control system including a solenoid-operated fluid-control valve operable to control the supply of fluid for operating the friction-engaging element of the transmission and thereby actuate the friction-engaging element to effect changes of drive ratio, and electrical circuit means connected to the solenoid valve and operable to supply a train of electrical pulses to the solenoid valve for a period after initiation of a change of drive ratio, at least one characteristic of the pulses in the train being variable in dependence upon variations in at least one variable operating parameter.
Claim 11
Dependent Claim
41 words
A system according to claim 8, wherein, at the end of the said period, the solenoid is supplied with continuous current if de-energized immediately before the said period, or is de-energized if supplied with continuous current immediately before the said period.
Claim 12
Dependent Claim
43 words
A system according to claim 9, wherein at least one of the group comprising the mark/space ratio, the frequency of the pulses and the duration of the period of theh pulses, is different on upward changes of ratio from downward changes of ratio.
Claim 13
Dependent Claim
72 words
A system according to claim 8, wherein the at least one variable pulse characteristic comprises at least one of the group comprising the mark/space ratio and the frequency of the pulses, which is varied in dependence on at least one variable operating parameter of an engine by which the system is driven, and wherein the period of the pulse train is preset and independent of the variable operating parameters of the engine.
Claim 14
Dependent Claim
34 words
A system according to claim 11, wherein the at least one parameter is at least one of the group comprising the speed, the torque, the throttle opening, and the manifold depression of the engine.
Claim 15
Dependent Claim
38 words
A system according to claim 12, wherein at least one of the group comprising the mark/space ratio and the frequency of the pulses is varied in dependence upon the speed of a load driven by the transmission system.
Claim 16
Dependent Claim
211 words
an automatic control system for use with an engine-driven automatic transmission which includes a friction-engaging element operable to change the drive ratio of the transmission, and a fluid supply connected to the friction-engaging element, the friction-engaging being actuated to effect a ratio change in dependence upon the supply of fluid thereto from said fluid supply, said control system including a solenoid valve operable to control the supply of fluid from said supply to the friction-engaging element of the transmission and thereby actuate the friction-engaging element to effect changes of drive ratio, and electrical circuit means connected to the solenoid of the solenoid valve and operable to supply a train of electrical pulses to the solenoid valve for a period after initiation of a change of drive ratio, at least one characteristic of the individual pulses in the train being varied in dependence upon variations in at least one variable operating parameter of the engine, whilst the period of the pulse train is preset and independent of variable operating parameters of the engine, said circuit means including a delay circuit operable to delay the supply of electricity to the solenoid valve or to delay the cutting off of the electricity from the solenoid valve after initiation of the change of drive ratio.
Claim 17
Dependent Claim
211 words
an automatic control system for use with an engine-driven automatic transmission which includes a friction-engaging element operable to change the drive ratio of the transmission, and a fluid supply connected to the friction-engaging element, the friction-engaging being actuated to effect a ratio change in dependence upon the supply of fluid thereto from said fluid supply, said control system including a solenoid valve operable to control the supply of fluid from said supply to the friction-engaging element of the transmission and thereby actuate the friction-engaging element to effect changes of drive ratio, and electrical circuit means connected to the solenoid of the solenoid valve and operable to supply a train of electrical pulses to the solenoid valve for a period after initiation of a change of drive ratio, at least one characteristic of the individual pulses in the train being varied in dependence upon variations in at least one variable operating parameter of the engine, whilst the period of the pulse train is preset and independent of variable operating parameters of the engine, said circuit means including a delay circuit operable to delay the supply of electricity to the solenoid valve or to delay the cutting off of the electricity from the solenoid valve after initiation of the change of drive ratio.
Claim 18
Dependent Claim
35 words
A system according to claim 14, wherein, upon a change of drive ratio, the supply of electricity to one solenoid valve is delayed after the supply of electricity is cut off from another solenoid valve.
Claim 19
Dependent Claim
30 words
A system according to claim 14, whereIn the cutting off at the supply of electricity from one solenoid valve is delayed after the supply of electricity to another solenoid valve.
Claim 20
Dependent Claim
53 words
An atuomatic transmission incorporating a control system as claimed in claim 16, and arranged to provide a plurality of different drive ratios, and in which failure of the supply of electricity to any of the energised solenoid valves will cause any ensuing change of ratio to be to a ratio nearer direct drive.
Claim 21
Dependent Claim
109 words
A system according to claim 2, wherein the circuit means includes an oscillator circuit controlled by at least one variable operating parameter of an engine by which the transmission is driven, and operable to produce said pulses in the train, at least one of the group comprising the mark/space ratio and the frequency of the pulses produced by the oscillator circuit being varied in dependence upon said at least one variable operating parameter, the circuit means further including a monostable circuit connected to the oscillator circuit so as to control the period of the pulse train output of the oscillator circuit independently of variable operating parameters of the engine.
Claim 22
Dependent Claim
53 words
A system according to claim 11, wherein said circuit means includes a monostable circuit which determines the period of the pulse train, and an oscillator circuit connected to and controlled by the monostable circuit, and also controlled by signals derived from variations in said at least one variable operating parameter of the engine.
Claim 23
Dependent Claim
53 words
A system according to claim 14, wherein said circuit means includes a monostable circuit which determines the period of the pulse train, and an oscillator circuit connected to and controlled by the monostable circuit, and also controlled by signals derived from variations in said at least one variable operating parameter of the engine.
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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) | 1978-03-03 | 1978-09-02 | 1979-03-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-03 | 1982-09-02 | 1983-03-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-03 | 1986-09-02 | 1987-03-04 | $7700.00 | Window Closed / Lapsed |