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:
May. 16, 1978
Filed:
Feb. 25, 1977
William R Scott, Andalusia, PA (US);
John M Carlyle, Willow Grove, PA (US);
The United States of America as represented by the Secretary of the Navy, Washington, DC (US);
Abstract
A device for acquiring and displaying acoustic emission fatigue data so as to facilitate the interpretation of dynamic micromechanical failure processes in materials. The load on a specimen under cyclic loading is monitored by a load cell whose output is sent to a cycle counter. The specimen is also monitored by a transducer which senses acoustic emissions. The signal produced by the transducer passes through a preamplifier, filter, amplifier and threshold detector to a pulse generator whose output is connected to the intensity modulation input of an oscilloscope or other cartesian coordinate arraying device. The load cell output is also connected to the vertical deflection input of the oscilloscope. The counter output is connected to the horizontal deflection input of the oscilloscope. Every time that the transducer detects an acoustic emission event, that event is represented on the oscilloscope in a two-dimensional cartesian coordinate system as a dot whose ordinate corresponds to the instantaneous load (derived from the load cell) and whose abscissa corresponds to the number of elapsed fatigue cycles (derived from the counter) at the time the event occurred, resulting in the simultaneous recording of the relationship between sample load, acoustic emission rate and number of fatigue cycles. By placing a screen splitter on the vertical deflection input to the oscilloscope, separate records of emissions under rising loads and under falling loads are produced.