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. 14, 1992
Filed:
Apr. 02, 1990
George E Thorsen, Wauwatosa, WI (US);
Harnischfeger Corporation, Brookfield, WI (US);
Abstract
A skew correction apparatus for a crane traveling on generally parallel spaced apart rails and having a drive wheel on each rail rotatably driven at the same speed. The drive wheels each have center cylindrical portions riding on a rail head and inside and outside flanges facing the sides of the rail head and having a larger diameter than the diameter of the center portion. The clearance distance between the inside flange of each drive wheel and the rail side it faces is smaller than the clearance distance between the outside flange and the rail side the outside flange faces. Thus, if the drive wheels and thereby the crane become skewed, only the inside drive wheel flanges will engage the rail sides. The lagging wheel of the skewed wheels will rotate against the rail side on the larger flange diameter of the wheel and tend to ride up on the rail side. Rotating on the larger flange diameter will increase the linear speed of the lagging wheel, since it continues to rotate at the same rotating speed as the leading wheel, so that it will catch up with the leading wheel and thereby correct the skew.