Patent ID: 6511393
Filing Date: 2003-01-28
Classification: F01L,F16H

Abstract:
A tensioning device (1) for a traction element (2) of a drive arrangement, said tensioning device comprising a tensioner-damper unit (9), a first tension element (7) in contact with the traction element (2) and a second tension element (10) in contact with the traction element (2), with the following features:the tensioner-damper unit (9) acts between a first pivoting lever (8) and a second pivoting lever (11), the first tension element (7) is connected to the first pivoting lever (8), the first pivoting lever (8) is mounted on a fulcrum for pivoting about a first fixed axis of pivot, the first tension element (7) is urged by the first pivoting lever (8), under the action of the tensioning force of the tensioner-damper unit (9), against a first strand (2a), the second tension element (10) is connected to the second pivoting lever (11), the second pivoting lever (11) is mounted on a fulcrum for pivoting about a second fixed axis of pivot, the second tension element (10) is urged by the second pivoting lever (11), under the action of the tensioning force of the tensioner-damper unit (9), against a second strand (2b), a deflector pully (5) for the traction element is arranged between the first strand (2a) and the second strand (2b) and the first strand (2a) and the second strand (2b) are subjected to unequal tractive forces, characterized by the following features:each of the first pivoting lever (8) and the second lever (11) is formed by an inner lever (8a, 11a) starting from its fulcrum and by an outer lever arm (8b, 11b) starting from its fulcrum, the free end of each outer lever arm (8a, 11b) is connected to the tension element (7, 10) associated thereto, the free end of each inner lever arm (8b, 11a) is articulated on one end of the tensioner-damper unit (9), the tensioner-damper unit (9) is float-mounted between the inner lever arms (8b, 11a) and transmits the reaction forces occurring during the tensioning operation between the first strand (2a) and the second strand (2b), the length of the inner lever arm (8a) and the outer lever arm (8b) of the first pivoting lever (8) and the length of the inner lever arm (11a) and of the outer lever arm (11b) of the second pivoting lever (11) form a ratio that is adapted to the unequal tractive forces, the length of the inner lever arm (8a) and of the outer lever arm (8b) of the first pivoting lever (8) form a ratio that produces a pre-tensionsing force on the first strand (2a), which pre-tensioning force is different in magnitude from a pre-tensioning force produced by the second pivoting lever (11) on the second strand (2b).