EP0260088A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Line pressure control system for an automatic transmission
Assignee: Subaru Corp
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Filing: 1987-09-07
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Granted: —
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Expires: 2007-09-07
Abstract
Abstract A microcomputer (Figure 2) is provided for controlling an automatic transmission for a motor vehicle. The microcomputer operates to control line pressure in a hydraulic circuit for the automatic transmission. A control circuit (45) is provided to respond to an output signal (37) of the microcomputer (Figure 2) for energizing a solenoid (56) to control the line pressure. A driving circuit (46) is provided to respond to closing operation of a starter motor switch (48) of an engine to energize the solenoid (50) to reduce the line pressure.
Inventors
- 👤 Ryuzo Sakakiyama
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-04 21:12
CPC Classifications
F; F02; F02N; F02N19/00; B; B60; B60W; B60W30/00; B60W30/18; B60W30/192; B60W30/194; F16; F16H; F16H61/00; F16H61/0021
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
133 words
A line pressure control system for an automatic transmission for a motor vehicle, the vehicle having a microcomputer which operates to control line pressure in a hydraulic circuit for the automatic transmission, in accordance with driving conditions of the motor vehicle, the system comprising: a solenoid (50) for controlling the line pressure; a control circuit (45) responsive to an output signal of the microcomputer for energizing the solenoid (50) to control the line pressure; a starting motor switch (48) for operating a starting motor of an engine of the motor vehicle; a driving circuit (46) electrically connected to the control circuit and to the starting motor switch, the driving circuit being arranged to respond to closing operation of the starting motor switch (48) to operate the solenoid (50) to reduce the line pressure.
Claim 2
Dependent Claim
133 words
A line pressure control system for an automatic transmission for a motor vehicle, the vehicle having a microcomputer which operates to control line pressure in a hydraulic circuit for the automatic transmission, in accordance with driving conditions of the motor vehicle, the system comprising: a solenoid (50) for controlling the line pressure; a control circuit (45) responsive to an output signal of the microcomputer for energizing the solenoid (50) to control the line pressure; a starting motor switch (48) for operating a starting motor of an engine of the motor vehicle; a driving circuit (46) electrically connected to the control circuit and to the starting motor switch, the driving circuit being arranged to respond to closing operation of the starting motor switch (48) to operate the solenoid (50) to reduce the line pressure.
Claim 3
Dependent Claim
31 words
A system as claimed in claim 1 wherein the output signal of the microcomputer is a pulse train duty ratio of which is controlled to control the energization of the solenoid.
Claim 4
Dependent Claim
49 words
A system as claimed in claim 2 wherein the control circuit includes a transistor (Tr-1) responsive to the pulses to intermittently energize the solenoid (50), and the driving circuit (46) includes transistors (Tr-2, Tr-3) responsive to the operation of the starting motor switch (48) to operate the solenoid (50>.
Claim 5
Dependent Claim
128 words
A line pressure control system for an automatic transmission for a motor vehicle having an engine, the system comprising: a microcomputer which operates to control line pressure in a hydraulic circuit for the automatic transmission, in accordance with driving conditions of the motor vehicle, a solenoid operated valve (50) for controlling the line pressure; a control circuit (45) responsive to an output signal of the microcomputer for energizing the solenoid (50) to control the line pressure; a starter motor switch (48) for operating a starter motor of the engine; and a driving circuit (46) connected to the control circuit and to the starter motor switch, and arranged to respond to closing operation of the starter motor switch (48) to operate the solenoid (50) to reduce the line pressure.
Claim 6
Dependent Claim
128 words
A line pressure control system for an automatic transmission for a motor vehicle having an engine, the system comprising: a microcomputer which operates to control line pressure in a hydraulic circuit for the automatic transmission, in accordance with driving conditions of the motor vehicle, a solenoid operated valve (50) for controlling the line pressure; a control circuit (45) responsive to an output signal of the microcomputer for energizing the solenoid (50) to control the line pressure; a starter motor switch (48) for operating a starter motor of the engine; and a driving circuit (46) connected to the control circuit and to the starter motor switch, and arranged to respond to closing operation of the starter motor switch (48) to operate the solenoid (50) to reduce the line pressure.
References Cited (Backward Citations)
No citation records indexed.
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