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:
Nov. 12, 1985
Filed:
Apr. 21, 1983
William E Coyle, Sr, Houma, LA (US);
Bilco Tools, Inc., Houma, LA (US);
Abstract
The power tongs control system described herein includes a hydraulic load transducer in the tongs snub line, the transducer output controlling a shunt valve between the hydraulic lines leading to and from the tongs drive motor. At a predetermined threshold tongs torque, a switch is actuated by contact with a Bourdon tube connected to the transducer output closure of the switch causing the solenoid actuator to open the shunt valve and thereby halt operation of the tongs. A timer is provided to maintain the tongs in the disabled configuration for a period of time following initial cut off. Also disclosed is an adjustable choke valve in series with the shunt valve so that even following the opening of the shunt valve, substantial torque is maintained upon the pipe by the tongs.