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. 20, 1997
Filed:
Aug. 06, 1996
Katsuya Nakakubo, Iruma, JP;
Toru Fujiwara, Tokorozawa, JP;
Tsubakimoto Chain Co., Osaka, JP;
Abstract
A tensioner includes a plunger slidably inserted in a housing and biased by spring means. The spring means include sequentially operable first and second portions in which the first portion has a relatively larger pitch and large spring modulus and the second portion has a relatively small pitch and small spring modulus. When the spring means is depressed a certain degree, the coils of the second spring portion 16 will move into close contact with each other to vary the spring modulus. Thus, the amount of backward movement and jutting out speed of the plunger will be decreased, thereby a required tensile force will be given to a belt, or the like, without delay.