| 摘要 |
PROBLEM TO BE SOLVED: To provide a power transmission mechanism capable of reducing unevenness in a transmission power load (limit torque) when power is shut off and having a simple mechanism maintaining a power shut-off condition. SOLUTION: A power transmission spring 44 is provided on a pulley 33, and a groove part 41 is provided in a hub 38. A connection piece 51 is engaged with the power transmission spring 44 and the groove part 41 to transmit power from the pulley 33 to the hub 38. A reengaging prevention spring 58 is provided on the connection piece 51, which is energized in the direction in which the engagement of the connection piece 51 and the groove part 41 is released. When a transmission power load between the pulley 33 and the hub 38 exceeds a predetermined value, the engagement of the connection piece 51 and the power transmission spring 44 is released due to elastic deformation of the power transmission spring 44. As a result, when a transmission power load exceeds the predetermined value, the connection piece 51 leaves both of the power transmission spring 44 and the groove part 41 to shut off power transmission.
|
