Combined base member and bit holder with protected retainer

摘要

The combined base member and bit holder with protected retainer which comprises this invention includes a bit holder adapted to receive the shank of a suitable cutting bit. The bit holder has a head which permits movement of the bit holder within the base member so as to expose means to receive a retaining member while that portion of the bit holder protrudes beyond the base member. The base member is provided with an opening or recess to receive the retainer so as to prevent accidental dislodgement. After installation of the retainer the bit holder is moved within the base member so as to engage the retainer at least partly in the recess provided in the base member for it, whereafter a spacer is driven between the head of the bit holder and body of the base member to hold the bit holder in place. A boss may be provided on the base member to prevent undue movement of the spacer. Means may also be provided in conjunction with the boss and/or base member to prevent the legs of the spacer from being spread so that the spacer also is prevented from accidental dislodgement. The bit holder may be provided with a flat to let it pass by the boss or it may be provided with a notch to receive the boss when the bit holder is moved to its initial position for installation of the retainer.