Method for determining a friction value
US6694798B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 25, 2002 |
| Grant date | Feb 24, 2004 |
| Priority date | — |
| Expiry date | Jul 25, 2022 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2342/044
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
The invention is based on a process for determination of a coefficient of friction (&mgr;) of a hydraulically activated coupling (4, 5, 6) or brake (7, 8, 9) in a load-shifting transmission (1). It is proposed that a drive shaft (14) of the transmission (1) be driven with a specified torque (T), that an output shaft (15) of the transmission (1) is blocked with a closed coupling (4, 5, 6) or brake (7, 8, 9) during a calibration run, the activation pressure (p) of coupling (4, 5, 6) or brake (7, 8, 9) is reduced in accordance with a specified course over time, the differential rotational speed (&Dgr;n) between the input (17, 18, 19) and the output (20) of the coupling (4, 5, 6) or brake (7, 8, 9) is recorded, the activation pressure (p) is ascertained in which the differential rotation speed (&Dgr;n) is greater than zero and a separation coefficient of friction (&mgr;separation) is computed on the basis of torque (T), activation pressure (p) and a construction-conditioned coupling constant. By ascertaining the coefficient of friction &mgr;, the shifting can be conducted over the lifetime of the transmission (1) with a constant shift quality.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.