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:
Apr. 14, 1981
Filed:
Apr. 18, 1979
Jack R Claycomb, Houston, TX (US);
Dresser Industries, Dallas, TX (US);
Abstract
A pressure pulse detection apparatus is disclosed which is adapted to receive small signals from downhole measuring while drilling apparatus which signals are propogated as pressure pulses traveling upstream in a column of drilling mud, which signals are obscured by mud pump pressure and velocity variations traveling downstream and which are significantly larger. The preferred embodiment incorporates a transient pressure transducer and an ultrasonic fluid velocity detector, the two forming output signals which are conditioned, amplified and offset against one another. They cancel (when properly calibrated) so that pressure and velocity variations from the mud pump upstream are nulled to zero. They reinforce so that pressure and velocity variations from the downhole signal generator are enhanced, thereby forming an output signal of downhole variations of interest.