Hydrostatic continuously variable transmission
US5356347A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 9, 1992 |
| Grant date | Oct 18, 1994 |
| Priority date | — |
| Expiry date | Dec 9, 2012 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H61/4017
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A hydrostatic continuously variable transmission includes a closed hydraulic circuit comprising a hydraulic pump, a hydraulic motor, and an oil supply passage connected between the hydraulic pump and the hydraulic motor. The hydraulic pump selectively generates a first oil pressure lower than a first predetermined pressure level, a second slowly-changing oil pressure higher than the first predetermined pressure level when the transmission is in normal operation, and a third rapidly-changing oil pressure higher than a second predetermined pressure level higher than the first predetermined pressure level when the transmission starts to operate. The transmission also includes a first pressure-responsive valve for connecting the oil supply passage to the oil tank in response to the first oil pressure applied through the oil supply passage, and disconnecting the oil supply passage from the oil tank in response to the second oil pressure applied through the oil supply passage, and a second pressure-responsive valve for connecting the oil supply passage to the oil tank in response to the third oil pressure applied through the oil supply passage, and disconnecting the oil supply passage fr…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.