US3604288A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic control system for automotive automatic transmission
Assignee: Nissan Motor Co Ltd
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Filing: 1969-10-29
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Granted: 1971-09-14
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Expires: 1989-10-29
Abstract
Abstract A system for electronically controlling the line pressure in the hydraulic control circuit of an automatic transmission of an automotive vehicle, which pressure is changed with a voltage proportional to the engine torque or inversely proportional to the speed of the turbine shaft of a torque converter.
Inventors
- 👤 Yoichi Mori
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:19
CPC Classifications
F; F16; F16H; F16H47/00; F16H47/06; F16H47/08
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
324 words
In an automatic transmission of an automotive vehicle including an engine of internal combustion type and a hydraulic control system having therein a line preSsure for selectively actuating friction elements of the transmission to effect shiftings of the transmission between a plurality of gear ratios, a voltage generator, and electronic control system for controlling a pressure level of the line pressure in dependence upon variable characteristics of torque transmitted from the engine to the transmission, said electronic control system comprising: engine torque detecting means connected to an intake manifold vacuum for generating an engine torque signal having a magnitude proportional to an engine torque; transmission output speed detecting means mounted on the transmission output shaft for detection of a revolutional speed of the transmission output shaft for generating a transmission output speed signal having a period proportional to a transmission output speed; gear ratio detecting means mounted for detection of a gear ratio, into which the transmission is to be shifted, for generating a gear ratio signal having a magnitude proportional to the gear ratio; electrohydraulic converting means for controlling the pressure level of said line pressure in dependence upon a level of voltage supplied thereto; negative gradient voltage converting means connected at one end with the voltage generator and at the other end to said electrohydraulic converting means receptive of said engine torque, transmission output speed and gear ratio signals for generating an output voltage having a magnitude inversely proportional to said transmission output speed; constant voltage converting means receptive of said engine torque signal connected at one end with said voltage generator and at the other end to said electrohydraulic converting means for generating a constant voltage having a magnitude determined by the voltage level of said engine torque signal; and comparating means receptive of said output voltages of said negative gradient and constant voltage converting means for selectively passing therethrough one of said two input voltages to said electrohydraulic converting means.
Claim 2
Dependent Claim
324 words
In an automatic transmission of an automotive vehicle including an engine of internal combustion type and a hydraulic control system having therein a line preSsure for selectively actuating friction elements of the transmission to effect shiftings of the transmission between a plurality of gear ratios, a voltage generator, and electronic control system for controlling a pressure level of the line pressure in dependence upon variable characteristics of torque transmitted from the engine to the transmission, said electronic control system comprising: engine torque detecting means connected to an intake manifold vacuum for generating an engine torque signal having a magnitude proportional to an engine torque; transmission output speed detecting means mounted on the transmission output shaft for detection of a revolutional speed of the transmission output shaft for generating a transmission output speed signal having a period proportional to a transmission output speed; gear ratio detecting means mounted for detection of a gear ratio, into which the transmission is to be shifted, for generating a gear ratio signal having a magnitude proportional to the gear ratio; electrohydraulic converting means for controlling the pressure level of said line pressure in dependence upon a level of voltage supplied thereto; negative gradient voltage converting means connected at one end with the voltage generator and at the other end to said electrohydraulic converting means receptive of said engine torque, transmission output speed and gear ratio signals for generating an output voltage having a magnitude inversely proportional to said transmission output speed; constant voltage converting means receptive of said engine torque signal connected at one end with said voltage generator and at the other end to said electrohydraulic converting means for generating a constant voltage having a magnitude determined by the voltage level of said engine torque signal; and comparating means receptive of said output voltages of said negative gradient and constant voltage converting means for selectively passing therethrough one of said two input voltages to said electrohydraulic converting means.
Claim 3
Dependent Claim
75 words
An electronic control system according to claim 1, wherein said comparating means is connected for comparing said output voltages of said negative gradient and constant voltage converting means and passes therethrough the lower output voltage of said two output voltages when said electrohydraulic converting means has such a positive characteristic as the pressure level of said line pressure produced therein is increased in proportion to the increase of the level of the voltage supplied thereto.
Claim 4
Dependent Claim
179 words
An electronic control system according to claim 2, wherein said negative gradient voltage converting means includes: a pulse shaper receptive of said transmission output speed signal for producing a shaped pulse of square wave having a period proportional to said transmission output speed, a pulse width modulator connected with said pulse shaper and a gear ratio signal generator receptive of said shaped pulse and gear ratio signal for producing a width modulated pulse having a width proportional to said gear ratio, a pulse amplitude modulator connected for reception of said width modulated pulse and engine torque signal for producing an amplitude modulated pulse having an amplitude proportional to said engine torque, and a low-pass filter connected for reception of said amplitude modulated pulse for producing a DC voltage signal having a magnitude inversely proportional to said transmission output speed and further connected with said comparing means, and wherein said constant voltage converting means includes; a voltage attenuator connected for reception of said engine torque signal for producing a constant DC voltage having a magnitude proportional to said engine torque.
Claim 5
Dependent Claim
78 words
An electronic control system according to claim 3, further comprising: engine speed detecting means mounted for detection of a revolutional speed of the engine for generating an engine speed signal having a period proportional to aN engine speed; and dividing means connected for reception of said engine speed signal and output voltage of said negative gradient voltage converting means for dividing said output voltage by said engine speed voltage and supplying the divided signal to said comparating means.
Claim 6
Dependent Claim
85 words
An electronic control system according to claim 4, wherein said dividing means includes: a pulse shaper connected for reception of said engine speed signal for producing a shaped pulse of square wave having a period proportional to said engine speed; a frequency divider connected for reception of said shaped pulse for producing a divided pulse having a multiplied period, and a timing-controlled integrator connected for reception of said divided pulse and amplitude modulated pulse for producing and supplying an integrated voltage to said low-pass filter.
Claim 7
Dependent Claim
72 words
An electronic control system according to claim 1, wherein said comparating means compares said output voltages of said negative gradient and constant voltage converting means and passes therethrough the higher output voltage of said two output voltages when said electrohydraulic converting means has such a negative characteristic as the pressure level of said line pressure produced therein is decreased in proportion to the increase of the level of the voltage supplied thereto.
Claim 8
Dependent Claim
188 words
An electronic control system according to claim 6, wherein said negative gradient voltage converting means includes: a pulse shaper connected for reception of said transmission output speed signal for producing a shaped pulse of square wave having a period proportional to said transmission output speed, a pulse width modulator connected for reception of said shaped pulse and gear ratio signal for producing a width modulated pulse having a width proportional to said gear ratio, a negative inverter connected for reception of said width modulated pulse for producing an inverted pulse having a width inverted from the width of said width modulated pulse, a pulse amplitude modulator connected for reception of said inverted pulse for producing an amplitude modulated pulse having an amplitude proportional to said engine torque, and a low-pass filter connected for reception of said amplitude modulated pulse for producing a DC voltage signal having a magnitude inversely proportional to said transmission output speed, and wherein said constant voltage-converting means includes a voltage attenuator connected for reception of said engine torque signal for producing a constant DC voltage signal having a magnitude proportional to said engine torque.
Claim 9
Dependent Claim
77 words
An electronic control system according to claim 7, further comprising: engine speed-detecting means connected for detection of a revolutional speed of the engine for generating an engine speed signal having a period proportional to an engine speed, and dividing means connected for reception of said engine speed signal and output voltage of said negative gradient voltage converting means for dividing said output voltage by said engine speed voltage and supplying the divided signal to said comparating means.
Claim 10
Dependent Claim
85 words
An electronic control system according to claim 8, wherein said dividing means includes: a pulse shaper connected for reception of said engine speed signal for producing a shaped pulse of square wave having a period proportional to said engine speed, a frequency divider connected for reception of said shaped pulse for producing a divided pulse having a multiplied period, and a timing-controlled integrator connected for reception of said divided pulse and amplitude modulated pulse for producing and supplying an integrated voltage to said low-pass filter.
Claim 11
Dependent Claim
15 words
An electronic control system according to claim 1, wherein said comparating means includes diode means.
Claim 12
Dependent Claim
16 words
An electronic control system according to claim 1, wherein said comparating means includes an analog comparator.
Claim 13
Dependent Claim
35 words
An electronic control system according to claim 1, further comprising: an amplifier connected for reception of said one of said two output voltages for amplifying and supplying said one output voltage to said electrohydraulic-converting means.
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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) | 1974-09-13 | 1975-03-15 | 1975-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-13 | 1979-03-15 | 1979-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-13 | 1983-03-15 | 1983-09-14 | $7700.00 | Window Closed / Lapsed |