Hugh Voris

US Patent:

44716575, Sep 18, 1984

Filed:

May 12, 1981

Appl. No.:

6/262796

Inventors:

Hugh A. Voris - Los Gatos CA
Kenneth R. Boyd - Santa Cruz CA
David A. Vossbrink - Santa Cruz CA

Assignee:

Stresstel Corporation - Scotts Valley CA

International Classification:

G01N 2900

US Classification:

73597

Abstract:

A digital ultrasonic extensometer for measuring the stress in a tensile load member, such as a bolt under load, the extensometer including a transducer permanently or temporarily in contact with the load member being measured, an intelligent processing means controlled time interval measuring means which generate a number of signals for energizing the transducer, the transducer, in turn, receiving the return pulse from the far end of the member under test and converting it into an electrical signal which is amplified and provided to the digital circuitry; the time interval measuring means then measure the number of clock pulses and portions of clock pulses during the period of time from the pulser signal to the receipt of the signal return from the end of the test member, provide a plurality of such pulse groups to the intelligent processing means, which enhance the accuracy of measurement by computational averaging computing, and indicate on a digital display and on an included paper printer, the computed indication of stress, length, elongation, temperature, and test member identifying information, such parameters being stored in the intelligent processing means having been either manually provided or internally determined as applicable.