Tensioning Device Pertaining to a Traction Mechanism Drive

Abstract

A tensioning device for a traction mechanism drive. The tensioning device includes a tensioning piston which is mounted in an axially movable manner and provided with an attachment shaft facing the traction mechanism. The tensioning device also includes a tensioning shoe formed of a polymer plastic and mounted on the attachment shaft via a support hole, and a disk-shaped metallic support element which is fixed to the attachment shaft via its support hole. The force transmission between the tensioning shoe ( 2 ) and the tensioning piston ( 5 ) is improved by pre-mounting the support element ( 11 ) in or on the tensioning shoe ( 2 ) in a positively or non-positively fixed manner, and the support element ( 11 ) is connected to the tensioning piston ( 5 ), in the mounted state, via a press fit between the support hole ( 12 ) and the attachment shaft ( 4 ), and contacts a shoulder ( 9 ) of the tensioning piston ( 5 ).

1 . Tensioning device for a traction mechanism drive, with a tensioning piston, which is supported so that it can move in an axial direction and which is provided with an attachment shaft facing a traction drive element, with a tensioning shoe, which is mounted with a support hole on the attachment shaft and which is made from polymer plastic, and with a disk-shaped, metallic support element fixed with a support hole on the attachment shaft, characterized in that the support element ( 11 ) is pre-mounted in a non-positive and/or positive-fit connection in or on the tensioning shoe ( 2 ) and in a mounted state, the support element ( 11 ) is connected to the tensioning piston ( 5 ), in particular, via a fit between its support hole ( 12 ) and the attachment shaft ( 4 ), and contacts a shoulder ( 9 ) of the tensioning piston ( 5 ). 
   
   
       2 . Tensioning device according to  claim 1 , characterized in that the support element ( 11 ) is extrusion coated with a polymer plastic of the tensioning shoe ( 2 ). 
   
   
       3 . Tensioning device according to  claim 1 , characterized in that the tensioning shoe ( 2 ) has on a side ( 13 ) facing the tensioning piston ( 5 ) an under-dimensioned recess ( 14 . 1 ), which is adapted to the support element ( 11 ) and in which the support element ( 11 ) is pressed. 
   
   
       4 . Tensioning device according to  claim 1 , characterized in that the tensioning shoe ( 2 ) has on a side ( 13 ) facing the tensioning piston ( 5 ) an over-dimensioned recess ( 14 . 2 ) adapted to the support element ( 11 ) with at least two projecting locking tabs ( 16 ), which are arranged on opposing edges ( 15 ) of the recess ( 14 . 2 ) and in which the support element ( 11 ) is pressed and locked. 
   
   
       5 . Tensioning device according to  claim 1 , characterized in that the tensioning shoe ( 2 ) is provided with a slot ( 17 ), which is open on one side and which is aligned parallel to a side ( 13 ) facing the tensioning piston ( 5 ) and which is adapted to the support element ( 11 ) and in which the support element ( 11 ) is pushed and fixed by pushing of the tensioning shoe ( 2 ) on the support shaft ( 4 ) of the tensioning piston ( 5 ). 
   
   
       6 . Tensioning device according to one of  claims 1  to  5 , characterized in that the attachment shaft ( 4 ) of the tensioning piston ( 5 ) and the support hole ( 12 ) of the support element ( 11 ) each have a correspondingly shaped element ( 18 . 1 ,  18 . 2 ) for mutual directional fixing. 
   
   
       7 . Tensioning device according to  claim 6 , characterized in that the shaped element ( 18 . 1 ) of the tensioning piston ( 5 ) is formed as a one-sided flattened section ( 19 . 1 ) of a circular cross section of the attachment shaft ( 4 ) and the shaped element ( 18 . 2 ) of the support element ( 11 ) is formed as a corresponding, one-sided flattened section ( 19 . 2 ) of a circular support hole ( 12 ) in the form of a secant. 
   
   
       8 . Tensioning device according to one of  claims 1  to  7 , characterized in that the support hole ( 12 ) of the support element ( 11 ) has a throat section ( 20 ) for reinforcing the locking on the support shaft ( 4 ) of the tensioning piston ( 5 ). 
   
   
       9 . Tensioning device according to  claim 8 , characterized in that the throat section ( 20 ) of the support hole ( 12 ) of the support element ( 11 ) is formed by an inward deviation from a circular hole edge ( 21 ). 
   
   
       10 . Tensioning device according to  claim 8  or  9 , characterized in that the throat section ( 20 ) of the support hole ( 12 ) of the support element ( 11 ) is formed by a construction of the hole ( 21 ) as a polygonal secant course ( 22 ).