| 摘要 |
A pneumatic power tool includes: a housing with a pressure air inlet passage, a rotation motor, a working implement carrying output shaft, and an over-speed safety device including: a valve element located in the inlet passage and shiftable between open and closed positions, a motor speed responsive actuating mechanism which can shift the valve element from an open to a closed position as motor speed reaches an accepted maximum limit, and a retaining unit which maintains the valve element in an open position at normal motor speed levels and releases it toward the closed position when actuated by the actuating mechanism. The retaining unit includes: a latch spindle having varying width in an axial direction and coupled to the actuating mechanism for displacement between valve element locking and releasing positions at the maximum speed limit, and a support surface and axially adjacently located one or more waist portions. |
