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:
Sep. 25, 1979
Filed:
Dec. 05, 1977
Applicant:
Inventors:
Earl R Johnson, Tulsa, OK (US);
Lesley G Watkins, Tulsa, OK (US);
Assignee:
Loffland Brothers, Tulsa, OK (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F16D / ;
U.S. Cl.
CPC ...
1882 / ; 188 / ;
Abstract
A hydraulic back-up system for use in combination with an equalizer beam of a drawworks brake system during the drilling of an oil and/or gas well bore for reducing the hazards in the event of failure of the drawworks braking system by automatically locking the equalizer beam in order that a single brake band of a two-brake band system will function for holding the load in an emergency situation.