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:
Jan. 07, 1992
Filed:
Jun. 13, 1990
Serge A Scherbatskoy, Fort Worth, TX (US);
Other;
Abstract
An apparatus for transmitting data to the surface of the earth in a borehole having a tubular drill string for circulating drilling fluid between the surface of the earth and downhole including a signal generator for providing electrical signals indicating a measured downhole condition, a valve within the apparatus moveable between a closed and an open condition for controlling, at least in part, the flow of drilling fluid, the valve being moved from closed toward open condition by the application of a first force, such as of a solenoid, and sequentially by a second force, such as a hydraulic fluid pressure differential across a piston to rapidly move the valve to the open condition, thereby creating a negative pressure pulse in the drilling fluid which pressure pulse is receivable at the earth's surface. In the preferred arrangement the fluid passageway within the apparatus includes an orifice for creating a lower pressure zone, the pressure of this zone being utilized to create a differential pressure across a piston to supply the secondary force for moving the valve towards the open condition.