Abnormality diagnosing device and abnormality diagnosing method for selection solenoid valve of automatic transmission
US11125323B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Aug 28, 2018 |
| Grant date | Sep 21, 2021 |
| Priority date | — |
| Expiry date | Sep 30, 2038 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2061/128
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
Selection solenoid valve (75) controls engagement/disengagement of travel clutch (31, 32) in synchronization with a selecting operation of selector lever (90) that selects a range position of belt-type continuously variable transmission (CVT). Selection solenoid valve abnormality diagnosing unit (8a) is configured to, when performing a selecting operation from no-drive range to drive range, if a time required for travel clutch (31, 32) to be judged to be engaged from a start of selection of the drive range is less than a predetermined time, judge selection solenoid valve (75) to be a maximum hydraulic pressure side abnormality. When performing the selecting operation of drive range→no-drive range→drive range, if a selecting operation speed condition indicating that a no-drive range selection time is shorter than a setting time (Tth) is satisfied, execution of abnormality diagnosis of selection solenoid valve (75) is not permitted. With this configuration, misjudgment is prevented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.