← Back to Patent Explorer
US5599254A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for diagnosing a fault in a lock-up mechanism of a torque converter fitted to an automatic transmission

Assignee: Hitachi Unisia Automotive Ltd
•
Filing: 1995-02-08
•
Granted: 1997-02-04
•
Expires: 2015-02-08
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A slip condition of a torque converter is learned at a predetermined operating condition with a lock-up mechanism disengaged, and a diagnosis condition (for example a start time or judgement level of the fault diagnosis) used in diagnosing a fault in the lock-up mechanism on the basis of slip conditions of the torque converter which change after issue of a disengage command to the lock-up mechanism, is corrected in accordance with the learned result. As a result, the diagnosis condition which is conventionally set assuming a maximum viscosity for the operating fluid, can be changed to correspond to the actual viscosity of the operating fluid being used. Hence, the time delay from issue of a disengage command to the lock-up mechanism until starting fault diagnosis can be reduced, so that it is possible to diagnose if normal lock-up mechanism disengagement is being made at a response speed which follows the demands for rapid lock-up mechanism disengagement under operating conditions including acceleration and deceleration operating conditions such as encountered with city driving and the like.

Inventors

  • 👤 Naoki Tomisawa
  • 👤 Keita Yoshizawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 07:49
CPC Classifications
F; F16; F16H; F16H61/00; F16H61/14; F16H61/143; F16H61/12; F16H59/00; F16H59/36; F16H59/38; F16H2059/385; F16H59/46; F16H2059/465; F16H2059/467; F16H2061/1208; F16H2061/1256; F16H2061/1276; F16H2061/145; F16H59/40; F16H59/68; F16H59/72

Claims Analysis

Total Claims: 36
Claim 1
Independent Claim 181 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the method comprising the steps of: detecting a rotational speed of the input shaft of the torque converter; detecting a rotational speed of the output shaft of the torque converter; detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; diagnosing a fault in the lock-up mechanism by comparing a slip condition of the torque converter after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism with a previously determined judgment value; learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and correcting the predetermined time as a diagnosis condition of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 2
Independent Claim 181 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the method comprising the steps of: detecting a rotational speed of the input shaft of the torque converter; detecting a rotational speed of the output shaft of the torque converter; detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; diagnosing a fault in the lock-up mechanism by comparing a slip condition of the torque converter after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism with a previously determined judgment value; learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and correcting the predetermined time as a diagnosis condition of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 3
Dependent Claim 47 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission according to claim 1, wherein the slip condition learning step is carrier out after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism.
Claim 4
Independent Claim 184 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the method comprising the steps of: detecting a rotational speed of the input shaft of the torque converter; detecting a rotational speed of the output shaft of the torque converter; detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; diagnosing a fault in the lock-up mechanism by comparing a slip condition of the torque converter after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism with a previously determined judgment value; learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and correcting the predetermined time and the judgment value as diagnosis conditions of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 5
Independent Claim 184 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the method comprising the steps of: detecting a rotational speed of the input shaft of the torque converter; detecting a rotational speed of the output shaft of the torque converter; detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; diagnosing a fault in the lock-up mechanism by comparing a slip condition of the torque converter after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism with a previously determined judgment value; learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and correcting the predetermined time and the judgment value as diagnosis conditions of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 6
Dependent Claim 47 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission according to claim 3, wherein the slip condition learning step is carrier out after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism.
Claim 7
Independent Claim 185 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the method comprising the steps of: detecting a rotational speed of the input shaft of the torque converter; detecting a rotational speed of the output shaft of the torque converter; detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; diagnosing a fault in the lock-up mechanism by comparing the required time from issuance of a disengage command to the lock-up mechanism until a slip condition of the torque converter reaches a previously determined judgment value, with a previously determined judgment time; learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and correcting the judgment time as a diagnosis condition of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 8
Independent Claim 185 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the method comprising the steps of: detecting a rotational speed of the input shaft of the torque converter; detecting a rotational speed of the output shaft of the torque converter; detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; diagnosing a fault in the lock-up mechanism by comparing the required time from issuance of a disengage command to the lock-up mechanism until a slip condition of the torque converter reaches a previously determined judgment value, with a previously determined judgment time; learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and correcting the judgment time as a diagnosis condition of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 9
Dependent Claim 47 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission according to claim 5, wherein the slip condition learning step is carrier out after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism.
Claim 10
Independent Claim 185 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the method comprising the steps of: detecting a rotational speed of the input shaft of the torque converter; detecting a rotational speed of the output shaft of the torque converter; detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; diagnosing a fault in the lock-up mechanism by comparing the required time from issuance of a disengage command to the lock-up mechanism until a slip condition of the torque converter reaches a previously determined judgment value, with a previously determined judgment time; learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and correcting the judgment value as a diagnosis condition of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 11
Independent Claim 185 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the method comprising the steps of: detecting a rotational speed of the input shaft of the torque converter; detecting a rotational speed of the output shaft of the torque converter; detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; diagnosing a fault in the lock-up mechanism by comparing the required time from issuance of a disengage command to the lock-up mechanism until a slip condition of the torque converter reaches a previously determined judgment value, with a previously determined judgment time; learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and correcting the judgment value as a diagnosis condition of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 12
Dependent Claim 47 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission according to claim 7, wherein the slip condition learning step is carrier out after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism.
Claim 13
Independent Claim 188 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the method comprising the steps of: detecting a rotational speed of the input shaft of the torque converter; detecting a rotational speed of the output shaft of the torque converter; detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; diagnosing a fault in the lock-up mechanism by comparing the required time from issuance of a disengage command to the lock-up mechanism until a slip condition of the torque converter reaches a previously determined judgment value, with a previously determined judgment time; learning a slip condition of the torque converter at a predetermined operating condition With the lock-up mechanism disengaged; and correcting the judgment time and the judgment value as diagnosis conditions of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 14
Independent Claim 188 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the method comprising the steps of: detecting a rotational speed of the input shaft of the torque converter; detecting a rotational speed of the output shaft of the torque converter; detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; diagnosing a fault in the lock-up mechanism by comparing the required time from issuance of a disengage command to the lock-up mechanism until a slip condition of the torque converter reaches a previously determined judgment value, with a previously determined judgment time; learning a slip condition of the torque converter at a predetermined operating condition With the lock-up mechanism disengaged; and correcting the judgment time and the judgment value as diagnosis conditions of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 15
Dependent Claim 47 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission according to claim 9, wherein the slip condition learning step is carrier out after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism.
Claim 16
Independent Claim 183 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the method comprising the steps of: detecting a rotational speed of the input shaft of the torque converter; detecting a rotational speed of the output shaft of the torque converter; detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; diagnosing a fault in the lock-up mechanism by comparing a change factor for the slip conditions of the torque converter, which slip conditions change after issuance of a disengage command to the lock-up mechanism, with a previously determined judgment value; learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and correcting the judgment value as a diagnosis condition of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 17
Independent Claim 183 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the method comprising the steps of: detecting a rotational speed of the input shaft of the torque converter; detecting a rotational speed of the output shaft of the torque converter; detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; diagnosing a fault in the lock-up mechanism by comparing a change factor for the slip conditions of the torque converter, which slip conditions change after issuance of a disengage command to the lock-up mechanism, with a previously determined judgment value; learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and correcting the judgment value as a diagnosis condition of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 18
Dependent Claim 47 words
A method of diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission according to claim 11, wherein the slip condition learning step is carrier out after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism.
Claim 19
Independent Claim 216 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the apparatus comprising: an input shaft rotational speed detecting means for detecting a rotational speed of the input shaft of the torque converter; an output shaft rotational speed detecting means for detecting a rotational speed of the output shaft of the torque converter; a slip detecting means for detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; a fault diagnosing means for diagnosing a fault in the lock-up mechanism by comparing a slip condition of the torque converter after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism with a previously determined judgment value; a slip condition learning means for learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and a diagnosis condition correction means for correcting the predetermined time as a diagnosis condition of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 20
Independent Claim 216 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the apparatus comprising: an input shaft rotational speed detecting means for detecting a rotational speed of the input shaft of the torque converter; an output shaft rotational speed detecting means for detecting a rotational speed of the output shaft of the torque converter; a slip detecting means for detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; a fault diagnosing means for diagnosing a fault in the lock-up mechanism by comparing a slip condition of the torque converter after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism with a previously determined judgment value; a slip condition learning means for learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and a diagnosis condition correction means for correcting the predetermined time as a diagnosis condition of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 21
Dependent Claim 46 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission according to claim 13, wherein the slip condition learning is carrier out after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism.
Claim 22
Independent Claim 218 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the apparatus comprising: an input shaft rotational speed detecting means for detecting a rotational speed of the input shaft of the torque converter; an output shaft rotational speed detecting means for detecting a rotational speed of the output shaft of the torque converter; a slip detecting means for detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; a fault diagnosing means for diagnosing a fault in the lock-up mechanism by comparing a slip condition of the torque converter after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism with a previously determined judgment value; a slip condition learning means for learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and a diagnosis condition correction means for correcting the predetermined time and judgment value as diagnosis conditions of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 23
Independent Claim 218 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the apparatus comprising: an input shaft rotational speed detecting means for detecting a rotational speed of the input shaft of the torque converter; an output shaft rotational speed detecting means for detecting a rotational speed of the output shaft of the torque converter; a slip detecting means for detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; a fault diagnosing means for diagnosing a fault in the lock-up mechanism by comparing a slip condition of the torque converter after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism with a previously determined judgment value; a slip condition learning means for learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and a diagnosis condition correction means for correcting the predetermined time and judgment value as diagnosis conditions of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 24
Dependent Claim 46 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission according to claim 15, wherein the slip condition learning is carrier out after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism.
Claim 25
Independent Claim 220 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the apparatus comprising: an input shaft rotational speed detecting means for detecting a rotational speed of the input shaft of the torque converter; an output shaft rotational speed detecting means for detecting a rotational speed of the output shaft of the torque converter; a slip detecting means for detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; a fault diagnosing means for diagnosing a fault in the lock-up mechanism by comparing the required time from issuance of a disengage command to the lock-up mechanism until a slip condition of the torque converter reaches a previously determined judgment value, with a previously determined judgment time; a slip condition learning means for learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and a diagnosis condition correction means for correcting the judgment time as a diagnosis condition of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 26
Independent Claim 220 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the apparatus comprising: an input shaft rotational speed detecting means for detecting a rotational speed of the input shaft of the torque converter; an output shaft rotational speed detecting means for detecting a rotational speed of the output shaft of the torque converter; a slip detecting means for detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; a fault diagnosing means for diagnosing a fault in the lock-up mechanism by comparing the required time from issuance of a disengage command to the lock-up mechanism until a slip condition of the torque converter reaches a previously determined judgment value, with a previously determined judgment time; a slip condition learning means for learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and a diagnosis condition correction means for correcting the judgment time as a diagnosis condition of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 27
Dependent Claim 46 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission according to claim 17, wherein the slip condition learning is carrier out after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism.
Claim 28
Independent Claim 220 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the apparatus comprising: an input shaft rotational speed detecting means for detecting a rotational speed of the input shaft of the torque converter; an output shaft rotational speed detecting means for detecting a rotational speed of the output shaft of the torque converter; a slip detecting means for detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; a fault diagnosing means for diagnosing a fault in the lock-up mechanism by comparing the required time from issuance of a disengage command to the lock-up mechanism until a slip condition of the torque converter reaches a previously determined judgment value, with a previously determined judgment time; a slip condition learning means for learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and a diagnosis condition correction means for correcting the judgment value as a diagnosis condition of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 29
Independent Claim 220 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the apparatus comprising: an input shaft rotational speed detecting means for detecting a rotational speed of the input shaft of the torque converter; an output shaft rotational speed detecting means for detecting a rotational speed of the output shaft of the torque converter; a slip detecting means for detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; a fault diagnosing means for diagnosing a fault in the lock-up mechanism by comparing the required time from issuance of a disengage command to the lock-up mechanism until a slip condition of the torque converter reaches a previously determined judgment value, with a previously determined judgment time; a slip condition learning means for learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and a diagnosis condition correction means for correcting the judgment value as a diagnosis condition of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 30
Dependent Claim 46 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission according to claim 19, wherein the slip condition learning is carrier out after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism.
Claim 31
Independent Claim 221 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the apparatus comprising: an input shaft rotational speed detecting means for detecting a rotational speed of the input shaft of the torque converter; an output shaft rotational speed detecting means for detecting a rotational speed of the output shaft of the torque converter; a slip detecting means for detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; a fault diagnosing means for diagnosing a fault in the lock-up mechanism by comparing the required time from issuance of a disengage command to the lock-up mechanism until a slip condition of the torque converter reaches a previously determined judgment value, with a previously determined judgment time; a slip condition learning means for learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and a diagnosis condition correction means for correcting the judgment time and value as diagnosis conditions of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 32
Independent Claim 221 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the apparatus comprising: an input shaft rotational speed detecting means for detecting a rotational speed of the input shaft of the torque converter; an output shaft rotational speed detecting means for detecting a rotational speed of the output shaft of the torque converter; a slip detecting means for detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; a fault diagnosing means for diagnosing a fault in the lock-up mechanism by comparing the required time from issuance of a disengage command to the lock-up mechanism until a slip condition of the torque converter reaches a previously determined judgment value, with a previously determined judgment time; a slip condition learning means for learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and a diagnosis condition correction means for correcting the judgment time and value as diagnosis conditions of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 33
Dependent Claim 46 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission according to claim 21, wherein the slip condition learning is carrier out after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism.
Claim 34
Independent Claim 218 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the apparatus comprising: an input shaft rotational speed detecting means for detecting a rotational speed of the input shaft of the torque converter; an output shaft rotational speed detecting means for detecting a rotational speed of the output shaft of the torque converter; a slip detecting means for detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; a fault diagnosing means for diagnosing a fault in the lock-up mechanism by comparing a change factor for the slip conditions of the torque converter, which slip conditions change after issuance of a disengage command to the lock-up mechanism, with a previously determined judgment value; a slip condition learning means for learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and a diagnosis condition correction means for correcting the judgment value as a diagnosis condition of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 35
Independent Claim 218 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission, the torque converter being connected to an output shaft of a vehicle engine, wherein the lock-up mechanism is provided for mechanically coupling input and output shafts of the torque converter, the apparatus comprising: an input shaft rotational speed detecting means for detecting a rotational speed of the input shaft of the torque converter; an output shaft rotational speed detecting means for detecting a rotational speed of the output shaft of the torque converter; a slip detecting means for detecting a slip condition of the torque converter based on the detected input shaft rotational speed and the detected output shaft rotational speed; a fault diagnosing means for diagnosing a fault in the lock-up mechanism by comparing a change factor for the slip conditions of the torque converter, which slip conditions change after issuance of a disengage command to the lock-up mechanism, with a previously determined judgment value; a slip condition learning means for learning a slip condition of the torque converter at a predetermined operating condition with the lock-up mechanism disengaged; and a diagnosis condition correction means for correcting the judgment value as a diagnosis condition of the fault diagnosis step in accordance with the learned result of the slip condition.
Claim 36
Dependent Claim 46 words
An apparatus for diagnosing a fault in a lock-up mechanism of a torque converter in an automatic transmission according to claim 23, wherein the slip condition learning is carrier out after lapse of a predetermined time from issuance of a disengage command to the lock-up mechanism.

References Cited (Backward Citations)

US4700819A Cited
US4724939A Cited
US4953677A Cited
JPH02195072A Cited
US5160002A Cited
US5190128A Cited
US5121820A Cited
US5332073A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 2000-02-04 2000-08-05 2001-02-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2004-02-04 2004-08-05 2005-02-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2008-02-04 2008-08-05 2009-02-04 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag