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:
Apr. 29, 1980
Filed:
Jul. 03, 1978
Richard M Anderson, Franklin, TN (US);
Richard F Beehler, Franklin, TN (US);
Heil-Quaker Corporation, Lewisburg, TN (US);
Abstract
A fluid flow device having a biased closure structure for selectively closing an opening in a flow conducting structure. The closure includes a pair of closure members pivoted relative to a transverse axis of the opening and biased to the closed position by a spring which is maintained spaced from the closure members in the closed position thereof. The spring has a midportion which is brought into engagement with the closure members as an incident of the movement thereof to and beyond a preselected position intermediate the closed and fully opened positions of the closure members. The spring acts to resiliently bias the closure members toward the closed position as result of the spring tension between the closed position and the intermediate position and the abutment of the midportion of the spring with the closure members at and beyond the intermediate position permits the closure members to be swung toward the fully open position with a decreased force.