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:
Mar. 10, 1992
Filed:
Sep. 11, 1991
Otis Elevator Company, Farmington, CT (US);
Abstract
In a curved escalator which has a return step run which is below the passenger-bearing run, the reversal step chain sprockets are of different diameters, the outer step chain sprockets being larger than the inner step chain sprockets. Since the steps are all tied together by the inner and outer step chains, the two chains must engage the inner and outer reversal sprocket teeth as the steps reverse their direction of movement. This results in a tipping of the step axles and steps during the turnaround, whereby a problem relating to engagement between the step chain rollers attached to the step axles and the sprocket teeth can occur. In order to maximize area contact between the tipped step chain rollers and the horizontal sprocket teeth, the step chain rollers which engage the sprocket teeth are formed with an external base-to-base truncated conical profile. This ensures that 50% of the surface of each profile roller will fully engage the sprocket teeth on the reversal sprockets.