The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 30, 1987
Filed:
Oct. 25, 1985
Frank B Bardsley, Andover, GB;
David E Stoddart, Stroud, GB;
Gearhart Tesel, Ltd., Basingstoke, GB;
Abstract
A tool for use downhole has means (18, 19, 20, 44) for engaging materials surrounding the hole. The engagement means (18, 19, 20, 44) are operated by hydraulic pressure controlled by a hydraulic circuit (10). A hydraulic power module (11) is provided for varying hydraulic pressure in the hydraulic circuit (10) to effect movement of the engagement means (18, 19, 20, 44). In case of failure, a dumping assembly (17) is provided to allow relief of hydraulic pressure in the circuit (10). The dumping assembly (17) includes a dump chamber (62) of variable volume, a dump valve (60) and a non-return valve (61); the hydraulic circuit being capable of being re-set downhole after dumping, there being no need to bring the tool to the surface.