Hydraulic shock absorber
US5083623A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 3, 1990 |
| Grant date | Jan 28, 1992 |
| Priority date | — |
| Expiry date | Dec 3, 2010 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B17/07
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A shock absorber apparatus for inclusion in a tool string which consists of outer and inner casings telescopically assembled with one casing having an uphole threaded joint member and the other casing having a downhole threaded joint member. The concentric casings then define spaced, sealed voids communicating through a metering sleeve clearance that are filled with a compressible oil. Shock wave induced relative movement of the casings from either direction causes a shock absorbing instantaneous displacement of oil from one void to the other via the metering clearance. Alternatively, coil springs may be disposed in the voids to aid in shock absorption.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.