Actuator for an appliance associated with a ducted body, especially a drill rod
US4821817A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 3, 1986 |
| Grant date | Apr 18, 1989 |
| Priority date | — |
| Expiry date | Jan 3, 2006 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16K17/30
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The device has, inside a duct (11) through which flows an incompressible fluid, a first profiled throttling element (17), a differential piston (10) subjected on one side to the pressure upstream of the profiled element (17) and on the other side to the pressure reduced by the element (17), a profiled surface (18) on the piston on the side subjected to the reduced pressure and a second profiled element (16) which are intended to interact to reduce the passage of fluid as a result of the movement of the piston in a first direction and increase the loss of head substantially, and a spring (15) returning the piston (10) in its second direction of movement. The device can serve particularly for actuating a stabilizer of a set of drill rods. In this case, the differential piston has inclined slopes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.