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. 14, 2016
Filed:
Feb. 12, 2014
James T. Dougherty, Indianapolis, IN (US);
James T. Dougherty, Indianapolis, IN (US);
Other;
Abstract
A unitary cam follower and valve preload spring for a desmodromic valve mechanism having opening and closing cams mounted in parallel on an overhead camshaft so as to facilitate positive bidirectional drive of a valve. The device comprises a generally tubular spring member of oblong transverse cross-section, a shaped extension spring, preferably a band or basket. The spring member is configured to be nonrotatably mounted on the camshaft with its longitudinal axis parallel to the camshaft axis and its major axis aligned with the valve stem axis, substantially surrounding the opening and closing cams circumferentially and engaging the valve stem and closing cam so as to pull the valve stem in response to an upward force applied to the upper portion of the spring member by the closing cam. The spring member is further configured to elongate along its major axis in response to tension applied thereto during assembly so as to preload the valve stem, and it has an effective spring rate which varies depending on conditions.