| 摘要 |
PROBLEM TO BE SOLVED: To provide a tensioner having simplified construction for increasing the strength of and reducing the backlash of locking teeth, reducing the number of components and cost, and improving flexibility in design. SOLUTION: The tensioner comprises a cylindrical member 1 having the plurality of locking teeth 1b, one or more locking top 2 having the locking teeth 2a for engaging with the locking teeth 1b, and a shaft member 3 having a locking top receiving portion for receiving the locking top and arranged inside the cylindrical member. One of the cylindrical member and the shaft member is a driven member to be driven in a forward/backward movable manner by energizing force. A ratchet mechanism is provided for permitting the forward movement of the driven member when the locking top is moved in the diameter shrinking direction to override the locking teeth of the cylindrical member, and for constraining the backward movement of the driven member when the locking top is moved in the diameter enlarging direction to engage with the locking teeth of the cylindrical member. The locking teeth are screwed teeth with leads, where the size and item of each part are set to establish an relationship of formula 3: R1×tanρ1+R2×tan(ρ2-θ)<0. COPYRIGHT: (C)2010,JPO&INPIT |
