A PULLEY ASSEMBLY

摘要

A tension roller for enabling adjustment of the tightness of a driving belt, comprising a solid support and a bearing press-fit thereon. The solid support has an axially extending mounting bore eccentrically arranged therein and a seating surface formed circumferentially thereon. A plurality of balanced bores are circumferentially distributed in the support in order to obtain a uniform radial elasticity at the seating surface. The balance bores may have a diameter equal to or less than the diameter of the mounting bore. In the latter case, the shortest distance between the balance bore surfaces and the seating surface is equal to the shortest distance between the mounting bore surface and the seating surface. The resultant uniformity of the radial elasticity prevents deformation of the bearing.