HAMMER DRILL FUNCTION SWITCH DEVICE OF A HAMMER DRILL FOR FIXING AND ADJUSTING THE ANGLE OF A CHISEL BIT AND PREVENTING THE BIT FROM BEING ROTATED IN USING A HAMMER

摘要

PURPOSE: A hammer drill function switch device of a hammer drill is provided to crush rectilinearly concrete or rocks in using a chisel by preventing a bit from being rotated and to secure a precise operation by controlling the angle and fixing the chisel bit. CONSTITUTION: A clutch(29) is moved vertically between a cylinder case(61) and a cylinder(38) to fix the cylinder in switching a hammer and press-fitted and fixed by a camp shaft bushing(32) by positioning at least one clutch pin(31) and a clutch spring(30) in a lower region. A clutch holder(33) disposed in the lower region of the clutch has at least one hole(33a) formed at an inner periphery to receive the lower region of the clutch pin in case of need. An operating hole faces the inside of the cylinder case, at which the clutch is positioned, from an upper region of the cylinder case. A clutch shaft(62) disposed in the operating hole has a sealing O-ring(63) and an eccentric projection(62a) for engaging or separating the clutch to/from a final gear(22) in switching the function to the hammer or a hammer drill. A change plate(64) fixes the clutch shaft to the cylinder case by a screw(67). A change lever(69) receives one end of the clutch shaft, fixes the clutch shaft by a screw(68), and has a change knob(65) elastically installed by a spring(66). The clutch pin is moved backward by the clutch spring and the change lever is smoothly operated and rotated to an original position thereof although the clutch pin is contacted with the surface of the clutch holder instead of the hole of the clutch holder. The clutch pin is fixed to the clutch holder by compressive force of the clutch spring to fix the cylinder when the cylinder is rotated at the predetermined angle.