Title:
FAIL-SAFE DEVICE OF CREEP PREVENTION APPARATUS FOR AUTOMATIC TRANSMISSION
Document Type and Number:
Japanese Patent JP3303699
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To guarantee that friction elements remain secured to each other even when a creep prevention apparatus in which the working pressure applied to the friction elements is controlled by a pressure control valve in such a way as to allow slipping of the friction elements, fails.
SOLUTION: From time t1 when N is shifted to D onward, a pressure control valve for creep prevention gradually builds up a forward clutch oil pressure Pc and a revolving speed N of a turbine drops when the relevant clutch is engaged. It is evaluated as normal if a torque converter slip amount ΔNA at time t2 following a set time interval Δts becomes larger than an instantaneous torque converter slip amount ΔN1 at the time t1 by a set value or more, and if not it is deemed abnormal. If the case is normal, the gradual increase of the pressure Pc is continued, and if abnormal, an instruction to maximize the pressure Pc is issued to the pressure control valve to prevent the transmission of power from being disabled. As apparent from the comparison with a slip amount ΔNB during high idling shown by a broken line, the instantaneous slip amount ΔNA at the time t2 is not affected by an increase in idling speed and the evaluation of anomalies is accurate.
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Inventors:
Suguru Murasugi
Hiromasa Sakai
Genji Nishio
Hiromasa Sakai
Genji Nishio
Application Number:
JP34511196A
Publication Date:
July 22, 2002
Filing Date:
December 25, 1996
Export Citation:
Assignee:
Nissan Motor Co., Ltd
International Classes:
F16H61/12; F16H61/20; F16H63/50; (IPC1-7): F16H61/20; F16H61/12
Domestic Patent References:
| JP6174079A | ||||
| JP61252947A | ||||
| JP552253A |
Attorney, Agent or Firm:
Akihide Sugimura (6 others)