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:
Feb. 18, 1992
Filed:
Jun. 07, 1991
Other;
Abstract
The invention is directed to a composite crankshaft for a two-stroke engine for portable handheld work tools including chain saws, cutoff machines and the like. In composite crankshafts, a crank pin is connected to a crank web by a press fit wherein the inner diameter of the press-fit bore is expanded toward its axial end in order to reduce stress peaks. In this way, the press-fit surface has a radial spacing with respect to the center longitudinal axis of the press fit which changes. The press fit of the crankshaft of the invention is so configured that the radial distance of the press-fit surface changes in dependence upon the axial spacing to the axial center of the press fit according to an exponential function having the equation f(x)=a.multidot.e.sup.b.multidot.x wherein (a) and (b) are pregiven constants, (x) is the axial spacing and f(x) is the radial spacing. In the composite crankshaft of the invention, stress fields produced by the press fit are substantially uniform and the load on the crankshaft is reduced.