Thermal fluid displacement actuator
US4070859A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 23, 1976 |
| Grant date | Jan 31, 1978 |
| Priority date | — |
| Expiry date | Dec 23, 1996 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF03G7/06113
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An electro-thermal fluid displacement actuator includes a fixed volume boiler chamber and a variable volume actuation chamber formed by a ported partition being received in the main body of the actuator between a positive temperature coefficient heat source for the contained fluid and an elastomeric diaphragm. Upon energization of the heat source, a portion of the contained fluid vaporizes to increase the pressure in the boiler chamber resulting in displacement of some of the remainingfluid through the partition ports and into contact with the diaphragm to drive the same and the piston assembly mounted thereon through the predetermined stroke thereof. The displaced fluid contacting the diaphragm has a lower temperature than the fluid adjacent the heater because of its passage through the ported partition to a position remote from such heater, such reduction in fluid temperature resulting in a lower permeation rate for the fluid through the elastomer and consequently increasing the life of the actuator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.