Fluid drive system
US4369855A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 15, 1980 |
| Grant date | Jan 25, 1983 |
| Priority date | — |
| Expiry date | Jul 15, 2000 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB60K17/10
- WIPO fieldTransport
- WIPO sectorMechanical engineering
Abstract
A hydraulic fluid drive for a land motor vehicle having front and rear drive wheels. An internal combustion engine drives a pair of positive displacement pumps. A first pump is connected to hydraulic motors that drive the front wheels of the vehicle. A second pump is connected to a hydraulic motor that drives a rear steerable wheel of the vehicle. A manually operated control is used to adjust the speed and torque of the motors for the front wheels. A front and rear wheel drive equalizing control operates in response to differences in hydraulic fluid pressure supplied to the front and rear hydraulic motors to equalize the fluid pressure pumped to the front and rear hydraulic motors so as to maintain the torque and speed of the front and rear wheels substantially constant. A foot operated lever is used to operate the control for the first pump for changing the supply of fluid pressure to the front wheel motors. The control apparatus includes a piston and cylinder assembly that interconnects the controls for the first and second pumps to control the second pumps in response to the hydraulic fluid output pressure of the first pump.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.