Four-wheel drive transfer case controller with compensation for tires with different diameters
US5809443A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 9, 1994 |
| Grant date | Sep 15, 1998 |
| Priority date | — |
| Expiry date | Dec 9, 2014 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60W2530/20
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A four-wheel drive vehicle includes a transfer case for controlling the delivery of power between the front and rear wheels of the vehicle. A clutch in the transfer case controls the amount of power delivered to the front and rear wheels in response to a clutch PulseWidth Modulated (PWM) signal which is generated by an electronic powertrain controller. The powertrain controller receives a first signal which is indicative of the rotational speed of a front driveshaft, which transfers motive power from the transfer case to a pair of front wheels, and a second signal which is indicative of the rotational speed of a rear driveshaft, which transfers motive power from the transfer case to a pair of rear wheels. The powertrain controller compensates for wheels which have a different effective diameter by determining the difference between the first signal and the second signal, filtering the difference to remove low frequency components, and generating the clutch PWM signal as a function of the high frequency components.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.