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:
Jul. 04, 1989
Filed:
Apr. 04, 1988
Martin M Gram, St. Louis Park, MN (US);
Luther E Johnson, St. Paul, MN (US);
Carl G Larsen, Plymouth, MN (US);
MTS Systems Corporation, Eden Prairie, MN (US);
Abstract
A tensile test grip for holding a specimen has a pullrod that is mounted in an annular bore, and carries a piston head that fits within a piston chamber, and both the pullrod and piston head are sealed on their outer surfaces with respect to the body forming the piston chamber, to form an enclosed chamber in which hydraulic fluid can be provided to permit swiveling alignment of the pullrod and the piston head relative to the housing that is a function of the direction of loading between the pullrod and the housing. The seal on the pullrod and the seal on the piston head with respect to the respective surfaces on which they seal is on a very short part spherical land to permit the pullrod and piston head to shift with respect to the housing and provide self alignment. The pullrod and piston can swivel freely for a limited amount to provide alignment during tensile loads. Spherical seats can be provided on the piston and arranged so that the seats can be locked together after initial alignment, to carry compression loads and permit testing the specimen in compression.