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:
Jan. 08, 1980
Filed:
Mar. 14, 1978
Carl G Dock, Hallstahammar, SE;
Nils G Schrewelius, Hallstahammar, SE;
Bulten-Kanthal AB, Hallstahammer, SE;
Abstract
A method for attaining a predetermined compressive stress is achieved by a device in the form of a washer, coating, or plug which as a function of pressure does not yield significantly, but when a predetermined pressure is reached, a sudden change in structure takes place which effects detonation of an explosive mixture which detonation is indicated by a sound, a puff of smoke, a change of appearance, a sudden release of heat, or an instantaneous increase in friction. The device includes a porous brittle body in which an explosive substance has been absorbed, and also preferably hard particles that aid in effecting detonation when the porous body goes through a physical change. The detonation can also join contact surfaces together, serve as an indication of desired prestress or torque applied to a fastener, to indicate a load limit, and the like.