Reversible hammer drill
AssigneeMilwaukee Electric Tool Corporation
InventorBarry L. Macky
Life of this patent
Estimating the term…
Abstract
When the hammer drill spindle and chuck are driven forward with the mode selection collar positioned to allow axial movement of the chuck and spindle, the annular ratchet is driven by the spindle through a one way roller clutch so it rides up the sloping surfaces of the fixed annular ratchet and then drops off the tooth corners to deliver a hammer blow of a magnitude determined by the operator pushing on the tool. If the rotation is reversed the clutch prevents rotation of the clutch input and prevents injury to the operator. If the selection collar is moved to lock the lugs in the detent notch of the cam surface the drill can be rotated either direction with the hammer action always locked out.
Claims4
A rotary hammer drill of the type having a drive spindle mounted in the housing for limited axial movement, a first ratchet member mounted on the spindle for axial movement with the spindle, a second ratchet member fixed in the housing, said ratchet members having confronting faces having complimentary ratchet faces which cam the first member from the second member when the spindle is rotated in the forward direction, characterized in that the spindle is driven by a reversible motor and a one way clutch is operatively connected between the spindle and said first ratchet member to drive the first ratchet member in the forward direction only.
Dependencies are inferred from the claim text.