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:
Jun. 07, 1988
Filed:
Oct. 24, 1986
Dantam K Rao, West Carrollton, OH (US);
Systran Corporation, Dayton, OH (US);
Abstract
A fatigue test apparatus in which a specimen to be tested is attached at its ends to a pair of opposing pistons positioned within a pair of opposing cylinders. The cylinders are attached to a support frame such that the specimen is oriented substantially vertically. In a preferred embodiment, the specimen is enclosed in a heat chamber to test at high temperatures. Each of the pistons is attached to a shaft having a weight at its end and the weights are drivingly connected to a pair of shakers which are actuated to vibrate 180.degree. out of phase with each other. The cylinders are pressurized to exert a static tensile load on the specimen, and the shakers are actuated to exert a dynamic tensile load which is superimposed on the static load and travels through the weights, shafts and pistons to the specimen. With this arrangement, the dynamic load is not transmitted to the support frame so that the vibration characteristics of the support frame do not affect the vibration behavior of the specimen, yielding a dynamic load source independent of static or thermal load sources. more accurate results. By varying the magnitude of the weights and the stiffness characteristics of the shafts, static, dynamic or thermal fatigue tests may be conducted on a specimen either singlely or in any combination with dynamic loads imposed at frequencies as high as 10,000 Hz.