Patent ID: 6688406
Filing Date: 2004-02-10
Classification: B25D

Abstract:
A power tool comprising:a motor; a gear mechanism coupled to and driven by said motor, said gear mechanism having a casing; a cylindrical housing mounted on said casing of said gear mechanism and formed with a pair of diametrically opposite radial holes therethrough; a spindle mounting seat disposed in said housing; a drive spindle mounted rotatably on said spindle mounting seat and coupled to and driven rotatably by said gear mechanism, said drive spindle being axially movable between front and rear limit positions relative to said spindle mounting seat; and a function control mechanism including a first ratchet mounted to rotate with said drive spindle, and having front and rear surfaces, said rear surface of said first ratchet being formed with first ratchet teeth, a second ratchet retained in said cylindrical housing, and having front surface and rear surfaces, said front surface of said second ratchet being formed with second ratchet teeth, said second ratchet being slidable in said cylindrical housing from a first position farther from said first ratchet to a second position closer to said first ratchet, said second ratchet teeth being disengaged from said first ratchet teeth when said second ratchet is in the first position, said second ratchet teeth being engaged with said first ratchet teeth when said second ratchet is in the second position and said drive spindle is in the rear limit position, a push ring disposed in said cylindrical housing and abutting against said rear surface of said second ratchet, said push ring having a pair of operable arms that extend radially and respectively through said radial holes in said cylindrical housing, said operable arms being movable between front and rear positions in said radial holes such that said second ratchet is in the first position when said operable arms are in the rear position, and such that said second ratchet is in the second position when said operable arms are in the front position, and a ring controller sleeved rotatably on said cylindrical housing, said ring controller being formed with a pair of circumferentially extending guide units, each of which is registered with a respective one of said radial holes in said cylindrical housing and is in sliding engagement with a respective one of said operable arms such that rotation of said ring controller relative to said cylindrical housing results in movement of said operable arms between the front and rear positions.