| 摘要 |
In a belt tensioning device comprising a fixed structure, a pivoted structure mounted with respect to the fixed structure for pivotal movement about a first axis between first and second limiting positions, a belt engaging pulley rotatably carried by the pivoted structure for rotational movement about a rotational axis parallel with the pivotal axis, a spring acting between the fixed and pivoted structures for resiliently biasing the pivoted structure to move in a direction away from the first limiting position toward the second limiting position so as to tension a belt engaged by the pulley, and a damping mechanism for damping the pivotal movements of the pivoted structure about the pivotal axis. The damping mechanism includes a stack of damping elements having interengaging pairs of surfaces disposed transversely with respect to the pivotal axis so as to be slidable with respect to one another in spaced planes of revolution about the pivotal axis. The stack includes a first plurality of damping elements and a second plurality of damping elements which are disposed within the stack in alternate positions with respect to the damping elements of the first plurality and which are mounted on the fixed and printed structures respectively applied to the opposite end element of the will cause the pairs of interengaging surfaces of the stack elements to move together and create a predetermined sliding friction therebetween when the pivoted structure is moved with respect to the fixed structure about the pivotal axis so as to provide a predetermined damping of such movement.
|
