EP0094627A2
Expired / Lapsed
EP
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Method and apparatus for controlling continuously variable transmission
Assignee: Nissan Motor Co Ltd
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Filing: 1983-05-11
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Granted: —
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Expires: 2003-05-11
Abstract
Abstract The reduction ratio of a continuously variable transmission is controlled by a shift motor. The shift motor is , controlled such that each of rotary positions thereof corresponds uniquely to a desired optimum reduction ratio. Upon detecting a state wherein a rapid shifting is needed, the shift motor is rotated at an increased revolution speed as compared to a normal revolution speed.
Inventors
- 👤 Yoshikazu Tanaka
- 👤 Keiju Abo
- 👤 Hiroyuki Hirano
- 👤 Haruyoshi Kumura
- 👤 Sigeaki Yamamuro
- 👤 Yoshiro Morimoto
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-28 05:07
CPC Classifications
B; B60; B60W; B60W30/00; B60W30/18; B60W10/00; B60W10/04; B60W10/10; B60W10/101; B60W30/1819; F; F16; F16H; F16H61/00; F16H61/66; B60W2510/00; B60W2510/06; B60W2510/0638; B60W2710/00; B60W2710/10; B60W2710/1005
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
91 words
A method for controlling a continously variable transmission of an automotive vehicle having an internal combustion engine, the transmission being shiftable between different reduction ratios and having a shift motor which is rotatable for effecting shifting between reduction ratios, the method comprising: detecting a state wherein a rapid shifting between reduction ratios is needed and generating a rapid shifting need indicative signal; and rotating the shift motor at an increased revolution speed in response to said rapid shifting need indicative signal to shorten the time required for shifting between reduction ratios.
Claim 2
Independent Claim
91 words
A method for controlling a continously variable transmission of an automotive vehicle having an internal combustion engine, the transmission being shiftable between different reduction ratios and having a shift motor which is rotatable for effecting shifting between reduction ratios, the method comprising: detecting a state wherein a rapid shifting between reduction ratios is needed and generating a rapid shifting need indicative signal; and rotating the shift motor at an increased revolution speed in response to said rapid shifting need indicative signal to shorten the time required for shifting between reduction ratios.
Claim 3
Dependent Claim
95 words
A method as claimed in claim 1, wherein said rapid shifting need indicative signal generating step includes: generating an actual rotary position indicative signal incicative of an actual rotary position of the shift motor; generating a desired rotary position indicative signal representing a desired rotary position of the shift motor; computing a difference between said actual rotary position indicative signal and said desired rotary position indicative signal and generating a difference indicative signal representing said difference; and generating said rapid shifting need indicative signal when said difference indicative signal is greater than a predetermined value.
Claim 4
Dependent Claim
158 words
A method as claimed in claim 1, wherein said rapid shifting need indicative signal generating step includes: generating an actual engine revolution speed indicative signal representing an actual engine revolution speed of the engine; generating a desired engine revolution speed indicative signal representing a desired engine revolution speed; subtracting a predetermined value from said desired engine revolution speed to result in a desired engine revolution speed lower limit value and generating a desired engine revolution speed lower limit value indicative signal representing said desired engine revolution speed lower limit value; computing a difference between said desired engine revolution speed indicative signal and said actual engine revolution speed indicative signal when said actual engine revolution speed indicative signal is less than said desired engine revolution speed lower limit value indicative signal and generating a difference indicative signal representing said difference; and generating said rapid shifting need indicative signal when said difference indicative signal is greater than a predetermined value.
Claim 5
Dependent Claim
146 words
A method as claimed in claim 1, wherein said rapid shifting need indicative signal generating step includes: generating an actual reduction ratio indicative signal representing an actual reduction ratio in the transmission; generating a desired reduction ratio indicative signal representing a desired reduction ratio; subtracting a predetermined value from said desired reduction ratio to result in a desired reduction ratio lower limit value and generating a desired reduction ratio lower limit value indicative signal representing said desired reduction ratio lower limit value; computing a difference between said desired reduction ratio indicative signal and said actual reduction ratio indicative signal when said actual reduction ratio indicative signal is less than said desired reduction ratio lower limit value indicative signal and generating a difference indicative signal representing said difference; and generating said rapid shifting need indicative signal when said difference indicative signal is higher than a predetermined value.
Claim 6
Dependent Claim
41 words
A method as claimed in claim 1, wherein the revolution speed of the shift motor when said rapid shifting need indicative signal is present is higher than that when said rapid shifting need indicative signal is absent by a predetermined value.
Claim 7
Dependent Claim
64 words
A method as claimed in claim 2, wherein the revolution speed of the shift motor when said rapid shifting need indicative signal is present is higher than that when said rapid shifting need indicative signal is absent by a value determined by a function having as a variable said difference between said actual rotary position indicative signal and said desired rotary position indicative signal.
Claim 8
Dependent Claim
66 words
A method as claimed in claim 3, wherein the revolution speed of the shift motor when said rapid shifting need indicative signal is present is higher than that when said rapid shifting need indicative signal is absent by a value determined by a function having as a variable said difference between said actual engine revolution speed indicative signal and said desired engine revolution speed indicative signal.
Claim 9
Dependent Claim
64 words
A method as claimed in claim 4, wherein the revolution speed of the shift motor when said rapid shifting need indicative signal is present is greater than that when said rapid shifting need indicative signal is absent by a value determined by a function having as a variable said difference between said actual reduction ratio indicative signal and said desired reduction ratio indicative signal.
Claim 10
Independent Claim
93 words
An apparatus for controlling a continously variable transmission of an automotive vehicle having an internal combustion engine, the transmission being shiftable between different reduction ratios, the apparatus comprising: a shift motor rotatable for effecting shifting between reduction ratios in the transmission; means for detecting a state wherein a rapid shifting between reduction ratios is needed and generating a rapid shifting need indicative signal; and means for rotating said shift motor at an increased speed in response to said rapid shifting need indicative signal to shorten the time required for shifting between reduction ratios.
Claim 11
Independent Claim
93 words
An apparatus for controlling a continously variable transmission of an automotive vehicle having an internal combustion engine, the transmission being shiftable between different reduction ratios, the apparatus comprising: a shift motor rotatable for effecting shifting between reduction ratios in the transmission; means for detecting a state wherein a rapid shifting between reduction ratios is needed and generating a rapid shifting need indicative signal; and means for rotating said shift motor at an increased speed in response to said rapid shifting need indicative signal to shorten the time required for shifting between reduction ratios.
Claim 12
Independent Claim
371 words
An apparatus for controlling a continuously variable transmission of an automotive vehicle having an internal combustion engine which is operatively connected to the continuously variable transmission, the continuously variable transmission having a V-belt running over a drive pulley and a driven pulley, at least one of which has a cylinder chamber and two conical discs, one conical disc being fixedly mounted to a shaft, the other conical disc being slidable mounted to the shaft and being controllably movable in an axial direction of the shaft in response to the fluid pressure in the cylinder chamber, the apparatus comprising: means for detecting vehicle speed of the automotive vehicle; means for detecting engine load on the internal combustion engine; means for retrieving a desired optimum reduction ratio for the detected vehicle speed and engine load and generating a desired optimum reduction ratio indicative signal; means for an actual reduction ratio indicative signal representing an actual reduction ratio of the continuously variable transmission; means for comparing the actual reduction ratio indicative signal with the desired optimum reduction ratio indicative signal to compute a difference therebetween and generating a difference indicative signal representing said difference; means for comparing said difference with a predetermined value and generating a rapid shifting need indicative signal when said difference is greater than said predetermined value; a shift motor rotatable between a plurality of rotary positions thereof; means operatively connected to said shift motor to be actuated thereby for regulating fluid supply to and discharge from the cylinder chamber to determine fluid pressure in the cylinder chamber to adjust the continuously variable transmission to a reduction ratio corresponding to one of the plurality of rotary positions of said shift motor assumed by said shift motor; and means for rotating said shift motor at a normal revolution speed until said actual reduction ratio indicative signal assumes a predetermined relation with said desired optimum reduction ratio indicative signal when said rapid shifting need indicatiove signal is absent, but rotating said shift motor at an increased revolution speed as compared to said normal revolution speed in response to said rapid shifting need indicative signal until said actual reduction ratio indicative signal assumes the predetermined relation with said desired optimum reduction ratio indicative signal.
Claim 13
Independent Claim
371 words
An apparatus for controlling a continuously variable transmission of an automotive vehicle having an internal combustion engine which is operatively connected to the continuously variable transmission, the continuously variable transmission having a V-belt running over a drive pulley and a driven pulley, at least one of which has a cylinder chamber and two conical discs, one conical disc being fixedly mounted to a shaft, the other conical disc being slidable mounted to the shaft and being controllably movable in an axial direction of the shaft in response to the fluid pressure in the cylinder chamber, the apparatus comprising: means for detecting vehicle speed of the automotive vehicle; means for detecting engine load on the internal combustion engine; means for retrieving a desired optimum reduction ratio for the detected vehicle speed and engine load and generating a desired optimum reduction ratio indicative signal; means for an actual reduction ratio indicative signal representing an actual reduction ratio of the continuously variable transmission; means for comparing the actual reduction ratio indicative signal with the desired optimum reduction ratio indicative signal to compute a difference therebetween and generating a difference indicative signal representing said difference; means for comparing said difference with a predetermined value and generating a rapid shifting need indicative signal when said difference is greater than said predetermined value; a shift motor rotatable between a plurality of rotary positions thereof; means operatively connected to said shift motor to be actuated thereby for regulating fluid supply to and discharge from the cylinder chamber to determine fluid pressure in the cylinder chamber to adjust the continuously variable transmission to a reduction ratio corresponding to one of the plurality of rotary positions of said shift motor assumed by said shift motor; and means for rotating said shift motor at a normal revolution speed until said actual reduction ratio indicative signal assumes a predetermined relation with said desired optimum reduction ratio indicative signal when said rapid shifting need indicatiove signal is absent, but rotating said shift motor at an increased revolution speed as compared to said normal revolution speed in response to said rapid shifting need indicative signal until said actual reduction ratio indicative signal assumes the predetermined relation with said desired optimum reduction ratio indicative signal.
Claim 14
Dependent Claim
36 words
An apparatus as claimed in claim 10, wherein said desired optimum reduction ratio indicative signal and said actual reduction ratio indicative signal are expressed in terms of the number of pulses supplied to said shift motor.
Claim 15
Dependent Claim
31 words
An apparatus as claimed in claim 10, wherein said desired optimum reduction ratio indicative signal and said actual reduction ratio indicative signal are expressed in terms of the engine revolution speed.
Claim 16
Dependent Claim
30 words
An apparatus as claimed in claim 10, wherein said desired optimum reduction ratio indicative signal and said actual reduction ratio indicative signal are expressed in terms of the reduction ratio.
Claim 17
Dependent Claim
40 words
An apparatus as claimed in claim 10, wherein said increased revolution speed at which said shift motor is rotated is a function of said difference between said actual reduction ratio indicative signal and said desired optimum reduction ratio indicative signal.
References Cited (Backward Citations)
No citation records indexed.
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