| 摘要 |
PROBLEM TO BE SOLVED: To provide a driving force transmission device for cutting off power transmission when driving force received by an input shaft is a predetermined limit torque value or greater, while changing the limit torque value with a rotating direction. SOLUTION: The power transmission device 1 includes a power transmission part 4 provided between the input shaft 2 and an output shaft 3 of the power transmission device 1 for cutting off power transmission when driving force received by the input shaft 2 is the predetermined limit torque value or greater, and a limit torque value changing mechanism 5 for changing the limit torque value with the rotating direction of the input shaft 2 during cutting off the power transmission. The limit torque value changing mechanism 5 consists of a ball 51 provided between a friction plate portion 6 of the power transmission part 4 and a spring 7 for sensing torque from the input shaft 2, and torque plates 52a, 52b having a ball storage groove 52x storing the ball 51. The depth of the ball storage groove 52x engaging with the ball 51 is changed with the rotating direction of the input shaft 2 to change elastic energizing force received from the spring 7 by the friction plate portion 6. COPYRIGHT: (C)2009,JPO&INPIT
|
