Power transmission device
US9086140B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 26, 2011 |
| Grant date | Jul 21, 2015 |
| Priority date | — |
| Expiry date | Dec 29, 2033 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16H2312/20
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A power transmission device that transmits power from a motor to a wheel via a hydraulically driven friction engagement element and that includes a mechanical pump driven by the motor to produce a hydraulic pressure that is regulated by a pressure regulating valve; an electric pump that produces a hydraulic pressure; a switching mechanism that either switches an output pressure of the regulating valve or an output pressure of the electric pump to a servo of the engagement element based upon a signal pressure; a passage to supply pressure from the mechanical pump to the hydraulic servo; a check valve in the passage that allows supply of the pressure from the mechanical pump to the hydraulic servo and prohibits supply of the pressure from the electric pump to the mechanical pump, and the switching mechanism either shuts off or allows communication through the passage based upon the signal pressure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.