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:
Dec. 11, 1984
Filed:
Feb. 01, 1982
Michel A Pierrat, Andover, MA (US);
Other;
Abstract
A method and apparatus for minimizing backlash and improving the efficiency of speed reduction mechanisms in which a series of rollers are equally spaced in a circle on a disk to perform operationally somewhat like an internal ring gear. Mounted for eccentric movement and simultaneously engaging each of the rollers is an orbital rotor having a perimeter defined by an epitrichoid curve with a number of lobes equal to one less than the number of rollers. The rotor is mounted for free rotation on an eccentric keyed to a drive shaft. Rotation of the drive shaft causes the rotor to move orbitally and to rotate with a speed reduction equal to the reciprocal of the number of lobes on the rotor. Each roller is mounted for controlled omnidirectional compliance and preloaded to provide a controlled pressure between each roller and the adjacent surface of the rotor. The outer surface of each roller is crowned to increase the efficiency and prevent binding that might be caused by angular deflection of the roller. Each roller is mounted on a shaft that is press-fitted into an eccentric bore in a mounting sleeve that is enlarged near the roller to provide for controlled deflection of the shaft as the sleeve is rotated in its mounting. Each roller is individually adjusted to produce a controlled preload pressure between the roller and the rotor.