US4790215A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and system for control of two part type transmission providing limited time for auxiliary transmission overdrive engagement with main transmission speed reduction engagement
Assignee: Toyota Motor Corp
•
Filing: 1987-12-14
•
Granted: 1988-12-13
•
Expires: 2007-12-14
Abstract
Abstract In the control of a vehicle automatic transmission having a series connection of an overdrive gear mechanism and an underdrive gear mechanism, the overdrive gear being switched over between direct connection and overdrive both when the underdrive gear mechanism is switched to direct connection and to speed reduction, a maximum limit is set for the period over which the overdrive gear mechanism is switched to overdrive while the underdrive gear mechanism is switched to speed reduction, such a maximum period being determined according to a vehicle operational parameter such as vehicle speed, throttle opening or transmission fluid temperature.
Inventors
- 👤 Yukio Hamano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 06:13
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/70; F16H61/702; F16H61/02; F16H61/0202; F16H61/0204; F16H61/0213; F16H2061/0241; F16H61/04; F16H2061/0451; F16H61/08; Y; Y10; Y10S; Y10S477/00; Y10S477/908
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
323 words
A transmission control method for an automatic transmission of a vehicle, said transmission comprising: (a) an auxiliary gear transmission mechanism, comprising a power input shaft and a power output shaft, and switchingly controllable to provide either a directly connected speed stage between its said power input shaft and its said power output shaft or a speed increasing overdrive speed stage between its said power input shaft and its said power output shaft, and; (b) a main gear transmission mechanism, comprising a power input shaft rotationally connected to said power output shaft of said auxiliary gear transmission mechanism and a power output shaft, and switchingly controllable to provide either a directly connected speed stage between its said power input shaft and its said power output shaft or at least one speed reducing speed stage between its said power input shaft and its said power output shaft; said method, comprising the steps of: (c) switching said auxiliary gear transmission mechanism between providing its said directly connected speed stage and providing its said speed increasing overdrive speed stage, both when said main gear transmission mechanism is switched to provide its said directly connected speed stage and when said main gear transmission mechanism is switched to its said speed reducing speed stage, so as to provide a series of speed stages of varying gear ratios by various combinations of said directly connected speed stage and said speed increasing overdrive speed stage of said auxiliary gear transmission mechanism and said directly connected speed stage and said speed reducing speed stage or stages of said main gear transmission mechanism, according to said vehicle operational parameters, and; (d) setting a maximum time limit period over which said auxiliary gear transmission mechanism is switched to provide its said speed increasing overdrive speed stage when said main gear transmission mechanism is switched to provide its said speed reducing speed stage, such a maximum period being determined according to a vehicle operational parameter.
Claim 2
Dependent Claim
323 words
A transmission control method for an automatic transmission of a vehicle, said transmission comprising: (a) an auxiliary gear transmission mechanism, comprising a power input shaft and a power output shaft, and switchingly controllable to provide either a directly connected speed stage between its said power input shaft and its said power output shaft or a speed increasing overdrive speed stage between its said power input shaft and its said power output shaft, and; (b) a main gear transmission mechanism, comprising a power input shaft rotationally connected to said power output shaft of said auxiliary gear transmission mechanism and a power output shaft, and switchingly controllable to provide either a directly connected speed stage between its said power input shaft and its said power output shaft or at least one speed reducing speed stage between its said power input shaft and its said power output shaft; said method, comprising the steps of: (c) switching said auxiliary gear transmission mechanism between providing its said directly connected speed stage and providing its said speed increasing overdrive speed stage, both when said main gear transmission mechanism is switched to provide its said directly connected speed stage and when said main gear transmission mechanism is switched to its said speed reducing speed stage, so as to provide a series of speed stages of varying gear ratios by various combinations of said directly connected speed stage and said speed increasing overdrive speed stage of said auxiliary gear transmission mechanism and said directly connected speed stage and said speed reducing speed stage or stages of said main gear transmission mechanism, according to said vehicle operational parameters, and; (d) setting a maximum time limit period over which said auxiliary gear transmission mechanism is switched to provide its said speed increasing overdrive speed stage when said main gear transmission mechanism is switched to provide its said speed reducing speed stage, such a maximum period being determined according to a vehicle operational parameter.
Claim 3
Dependent Claim
45 words
A method of transmission control according to claim 1, wherein, at the end of said maximum period said auxiliary gear transmission mechanism is switched to provide its said directly connected speed stage and said main gear transmission mechanism is shifted up by one speed stage.
Claim 4
Dependent Claim
18 words
A method of transmission control according to claim 1, wherein said vehicle operational parameter is engine rotational speed.
Claim 5
Dependent Claim
28 words
A method of transmission control according to claim 3, wherein said maximum period is determined to be a monotonically decreasing function of engine power output shaft rotational speed.
Claim 6
Dependent Claim
34 words
A method of transmission control according to claim 3, wherein, when engine power output shaft rotational speed is less than a determinate engine power output shaft rotational speed value, said maximum period is infinite.
Claim 7
Dependent Claim
168 words
A method of transmission control according to claim 3, said main gear transmission mechanism further being switchingly controllable to provide a higher first speed reducing speed stage between its said power input shaft and its said power output shaft and a lower second speed reducing speed stage between its said power input shaft and its said power output shaft, wherein: with said main gear transmission mechanism being switched to provide said higher first speed reducing speed stage, when engine power output shaft rotational speed is less than a first determinate engine power output shaft rotational speed value said maximum period is infinite, and, with said main gear transmission mechanism being switched to provide said lower second speed reducing speed stage, when engine power output shaft rotational speed is less than a second determinate engine power output shaft rotational speed value said maximum period is infinite; said second determinate engine power output shaft rotational speed value being lower than said first determinate engine power output shaft rotational speed value.
Claim 8
Dependent Claim
23 words
A method of transmission control according to claim 1, wherein said vehicle operational parameter is a rotational speed of a rotating transmission element.
Claim 9
Dependent Claim
29 words
A method of transmission control according to claim 7, wherein said maximum period is determined to be a monotonically decreasing function of rotational speed of said rotating transmission element.
Claim 10
Dependent Claim
31 words
A method of transmission control according to claim 7, wherein, when rotational speed of said rotating transmission element is less than a determinate rotational speed value, said maximum period is infinite.
Claim 11
Dependent Claim
162 words
A method of transmission control according to claim 7, said main gear transmission mechanism further being switchingly controllable to provide a higher first speed reducing speed stage between its said power input shaft and its said power output shaft and a lower second speed reducing speed stage between its said power input shaft and its said power output shaft, wherein: with said main gear transmission mechanism being switched to provide said higher first speed reducing speed stage, when rotational speed of said rotating transmission element is less than a first determinate transmission element rotational speed value said maximum period is infinite, and, with said main gear transmission mechanism being switched to provide said lower second speed reducing speed stage, when rotational speed of said rotating transmission element is less than a second determinate transmission element rotational speed value said maximum period is infinite; said second determinate transmission element rotational speed value being lower than said first determinate transmission element rotational speed value.
Claim 12
Dependent Claim
18 words
A method of transmission control according to claim 1, wherein said vehicle operational parameter is vehicle road speed.
Claim 13
Dependent Claim
25 words
A method of transmission control according to claim 11, wherein said maximum period is determined to be a monotonically decreasing function of vehicle road speed.
Claim 14
Dependent Claim
28 words
A method of transmission control according to claim 11, wherein, when vehicle road speed is less than a determinate vehicle road speed value, said maximum period is infinite.
Claim 15
Dependent Claim
150 words
A method of transmission control according to claim 11, said main gear transmission mechanism further being switchingly controllable to provide a higher first speed reducing speed stage between its said power input shaft and its said power output shaft and a lower second speed reducing speed stage between its said power input shaft and its said power output shaft, wherein: with said main gear transmission mechanism being switched to provide said higher first speed reducing speed stage, when vehicle road speed is less than a first determinate vehicle road speed value said maximum period is infinite, and, with said main gear transmission mechanism being switched to provide said lower second speed reducing speed stage, when vehicle road speed is less than a second determinate vehicle road speed value said maximum period is infinite; said second determinate vehicle road speed value being lower than said first determinate vehicle road speed value.
Claim 16
Dependent Claim
20 words
A method of transmission control according to claim 1, wherein said vehicle operational parameter is a value representing engine load.
Claim 17
Dependent Claim
24 words
A method of transmission control according to claim 15, wherein said maximum period is determined to be a monotonically decreasing function of engine load.
Claim 18
Dependent Claim
18 words
A method of transmission control according to claim 1, wherein said vehicle operational parameter is transmission fluid temperature.
Claim 19
Dependent Claim
25 words
A method of transmission control according to claim 17, wherein said maximum period is determined to be a monotonically decreasing function of transmission fluid temperature.
Claim 20
Dependent Claim
319 words
A transmission control system for automatic transmission of a vehicle, said transmission comprising: (a) an auxiliary gear transmission mechanism, comprising a power input shaft and a power output shaft, and switchingly controllable to provide either a directly connected speed stage between its said power input shaft and its said power output shaft or a speed increasing overdrive speed stage between its said power input shaft and its said power output shaft, and; (b) a main gear transmission mechanism, comprising a power input shaft rotationally connected to said power output shaft of said auxiliary gear transmission mechanism and a power output shaft, and switchingly controllable to provide either a directly connected speed stage between its said power input shaft and its said power output shaft or at least one speed reducing speed stage between its said power input shaft and its said power output shaft; said system comprising: (c) a means for switching said auxiliary gear transmission mechanism between its said directly connected speed stage and its said speed increasing overdrive speed stage according to vehicle operational parameters, both when said main gear transmission mechanism is switched to its said directly connected speed stage and when said main gear transmission mechanism is switched to its said speed reducing speed stage, so as to provide a series of speed stages of varying gear ratios by various combinations of said directly connected speed stage and said speed increasing overdrive speed stage of said auxiliary gear transmission mechanism and said directly connected speed stage and said speed reducing speed stage or stages of said main gear transmission mechanism, and; (d) a means for setting a maximum limit period for which said auxiliary gear transmission mechanism is switched to provide its said speed increasing overdrive speed stage when said main gear transmission mechanism is switched to provide its said speed reducing speed stage, said maximum period being determined according to a vehicle operational parameter.
Claim 21
Dependent Claim
319 words
A transmission control system for automatic transmission of a vehicle, said transmission comprising: (a) an auxiliary gear transmission mechanism, comprising a power input shaft and a power output shaft, and switchingly controllable to provide either a directly connected speed stage between its said power input shaft and its said power output shaft or a speed increasing overdrive speed stage between its said power input shaft and its said power output shaft, and; (b) a main gear transmission mechanism, comprising a power input shaft rotationally connected to said power output shaft of said auxiliary gear transmission mechanism and a power output shaft, and switchingly controllable to provide either a directly connected speed stage between its said power input shaft and its said power output shaft or at least one speed reducing speed stage between its said power input shaft and its said power output shaft; said system comprising: (c) a means for switching said auxiliary gear transmission mechanism between its said directly connected speed stage and its said speed increasing overdrive speed stage according to vehicle operational parameters, both when said main gear transmission mechanism is switched to its said directly connected speed stage and when said main gear transmission mechanism is switched to its said speed reducing speed stage, so as to provide a series of speed stages of varying gear ratios by various combinations of said directly connected speed stage and said speed increasing overdrive speed stage of said auxiliary gear transmission mechanism and said directly connected speed stage and said speed reducing speed stage or stages of said main gear transmission mechanism, and; (d) a means for setting a maximum limit period for which said auxiliary gear transmission mechanism is switched to provide its said speed increasing overdrive speed stage when said main gear transmission mechanism is switched to provide its said speed reducing speed stage, said maximum period being determined according to a vehicle operational parameter.
Claim 22
Dependent Claim
47 words
A system for transmission control according to claim 19, further comprising a means for, at the end of said maximum period switching said auxiliary gear transmission mechanism to provide its said directly connected speed stage and shifting said main gear transmission mechanism up by one speed stage.
Claim 23
Dependent Claim
18 words
A system for transmission control according to claim 19, wherein said vehicle operational parameter is engine rotational speed.
Claim 24
Dependent Claim
30 words
A system for transmission control according to claim 21, wherein said determining means determines said maximum period to be a monotonically decreasing function of engine power output shaft rotational speed.
Claim 25
Dependent Claim
34 words
A system for transmission control according to claim 21, wherein, when engine power output shaft rotational speed is less than a determinate engine power output shaft rotational speed value, said maximum period is infinite.
Claim 26
Dependent Claim
168 words
A system for transmission control according to claim 21, said main gear transmission mechanism further being switchingly controllable to provide a higher first speed reducing speed stage between its said power input shaft and its said power output shaft and a lower second speed reducing speed stage between its said power input shaft and its said power output shaft, wherein: with said main gear transmission mechanism being switched to provide said higher first speed reducing speed stage, when engine power output shaft rotational speed is less than a first determinate engine power output shaft rotational speed value said maximum period is infinite, and, with said main gear transmission mechanism being switched to provide said lower second speed reducing speed stage, when engine power output shaft rotational speed is less than a second determinate engine power output shaft rotational speed value said maximum period is infinite; said second determinate engine power output shaft rotational speed value being lower than said first determinate engine power output shaft rotational speed value.
Claim 27
Dependent Claim
23 words
A system for transmission control according to claim 19, wherein said vehicle operational parameter is a rotational speed of a rotating transmission element.
Claim 28
Dependent Claim
31 words
A system for transmission control according to claim 25, wherein said determining means determines said maximum period to be a monotonically decreasing function of rotational speed of said rotating transmission element.
Claim 29
Dependent Claim
31 words
A system for transmission control according to claim 25, wherein, when rotational speed of said rotating transmission element is less than a determinate rotational speed value, said maximum period is infinite.
Claim 30
Dependent Claim
162 words
A system for transmission control according to claim 25, said main gear transmission mechanism further being switchingly controllable to provide a higher first speed reducing speed stage between its said power input shaft and its said power output shaft and a lower second speed reducing speed stage between its said power input shaft and its said power output shaft, wherein: with said main gear transmission mechanism being switched to provide said higher first speed reducing speed stage, when rotational speed of said rotating transmission element is less than a first determinate transmission element rotational speed value said maximum period is infinite, and, with said main gear transmission mechanism being switched to provide said lower second speed reducing speed stage, when rotational speed of said rotating transmission element is less than a second determinate transmission element rotational speed value said maximum period is infinite; said second determinate transmission element rotational speed value being lower than said first determinate transmission element rotational speed value.
Claim 31
Dependent Claim
18 words
A system for transmission control according to claim 24, wherein said vehicle operational parameter is vehicle road speed.
Claim 32
Dependent Claim
27 words
A system for transmission control according to claim 29, wherein said determining means determines said maximum period to be a monotonically decreasing function of vehicle road speed.
Claim 33
Dependent Claim
28 words
A system for transmission control according to claim 29, wherein, when vehicle road speed is less than a determinate vehicle road speed value, said maximum period is infinite.
Claim 34
Dependent Claim
150 words
A system for transmission control according to claim 29, said main gear transmission mechanism further being switchingly controllable to provide a higher first speed reducing speed stage between its said power input shaft and its said power output shaft and a lower second speed reducing speed stage between its said power input shaft and its said power output shaft, wherein: with said main gear transmission mechanism being switched to provide said higher first speed reducing speed stage, when vehicle road speed is less than a first determinate vehicle road speed value said maximum period is infinite, and, with said main gear transmission mechanism being switched to provide said lower second speed reducing speed stage, when vehicle road speed is less than a second determinate vehicle road speed value said maximum period is infinite; said second determinate vehicle road speed value being lower than said first determinate vehicle road speed value.
Claim 35
Dependent Claim
20 words
A system for transmission control according to claim 19, wherein said vehicle operational parameter is a value representing engine load.
Claim 36
Dependent Claim
26 words
A system for transmission control according to claim 33, wherein said determining means determines said maximum period to be a monotonically decreasing function of engine load.
Claim 37
Dependent Claim
18 words
A system for transmission control according to claim 19, wherein said vehicle operational parameter is transmission fluid temperature.
Claim 38
Dependent Claim
27 words
A system for transmission control according to claim 35, wherein said determining means determines said maximum period to be a monotonically decreasing function of transmission fluid temperature.
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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) | 1991-12-13 | 1992-06-13 | 1992-12-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-12-13 | 1996-06-13 | 1996-12-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-12-13 | 2000-06-13 | 2000-12-13 | $7700.00 | Window Closed / Lapsed |