Patent ID: 8322459
Filing Date: 2012-12-04
Classification: B25F

Abstract:
1. A pneumatic power tool comprising: a housing; a pneumatic motor mounted in said housing; an air control unit coupled to said pneumatic motor and displaceable from a shut-off state to an entry state where a pressured air is introduced in said pneumatic motor; a drive coupler drivenly coupled to said pneumatic motor to rotate about an axis, and axially movable relative to said housing between depressed and non-working positions that correspond to the entry and shut-off states, respectively, said drive coupler having an outer surrounding region surrounding the axis; a latch which has an actuated end, and which is received in and which is radially movable in said drive coupler between a latched position where said actuated end is disposed radially and outwardly of said drive coupler, and an unlatched position; a tappet configured to be axially movable relative to said drive coupler such that, when said latch is in the latched position, said tappet is axially engaged with said latch to move with said drive coupler to the depressed position so as to displace said air control unit to the entry state, and such that, when said latch is in the unlatched position, said tappet is axially disengaged from said latch to permit axial movement of said tappet so as to displace said air control unit to the shut-off state; an output spindle having a shank which is disposed in said housing and which extends axially to terminate at a bit-side end exposed out of said housing, and at a clutch-side end portion disposed opposite to said bit-side end, said clutch-side end portion having a flared segment which extends outwardly and radially and which has an upward bearing surface, said upward bearing surface defining a plurality of ball-engaging areas angularly displaced from one another about the axis; a coupling shell member which surrounds said outer surrounding region of said drive coupler and which has an inner shell surface including actuating and engaging regions axially opposite to each other; and an override clutch unit including