Patent ID: 6146300
Filing Date: 2000-11-14
Classification: F16H

Abstract:
A tensioner device for a chain drive mechanism including at least two sprockets spaced from each other on a stationary member, and an endless chain wound around the sprockets, said tensioner device comprising:a tensioner lever having one end pivoted to the stationary member, said tensioner lever being in slide contact with the chain between the sprockets to adjust a tension in the chain;a first tensioner assembly including a first housing, a plunger movable in a forward direction relative to said first housing, a spring urging said plunger toward the forward direction, and a stop means for preventing backward movement of said plunger;a second tensioner assembly including a second housing, a piston movable in a forward and a backward direction relative to said second housing, a spring urging said piston toward the forward direction, and means for restricting backward movement of said piston while allowing forward movement of said piston;one of said first and second tensioner assemblies being provided on said tensioner lever, and the other tensioner assembly being provided on the stationary member;said plunger and said piston being in face-to-face abutment with each other; andsaid spring of said first tensioner assembly having a spring coefficient smaller than a spring coefficient of the spring of said second tensioner assembly.