Electrical activation of a viscous clutch
US7628262B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 28, 2006 |
| Grant date | Dec 8, 2009 |
| Priority date | — |
| Expiry date | Feb 17, 2028 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16D2500/3064
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A system for controlling the engagement and disengagement of a viscous type coupling is accomplished by controlling the relative positioning of a spring loaded valve arm relative to a fluid port through the use of an electrically-activated, temperature-sensitive member, such as a NiTi wire. The characteristics of shape memory alloy materials are such that they are hard above a predetermined temperature, but soft and ductile below a predetermined temperature. When engagement or disengagement of the coupling is desired, electrical current is introduced through the member, therein heating it above a predetermined temperature to harden it. This hardening causes the valve arm to either move to either cover or uncover a fluid port, depending upon the design arrangement of the valve arm relative to the fluid port. A controller coupled to a plurality of engine operating sensors and a power source controls the electrical activation as a function of a desired operating condition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.