Apparatus for driving a drilling or percussion tool

In a portable power tool of the type having a housing with a handle portion, said housing containing an electric motor which powers a cooling fan and which also actuates a tool holder for releasably retaining a working tool element, the improvement comprising:

• (a) said housing being provided with an intake opening oriented with respect to said cooling fan such that upon energization of the motor air is caused to flow into the tool housing through said opening for cooling said motor;
• (b) a drill foot mounted from the tool housing and located adjacent the working end of said tool element, said drill foot defining a chamber with an opening for collecting material dislodged by said tool element;
• (c) a substantially cylindrical auxiliary handle secured to said housing, said auxiliary handle being hollow and thereby defining a cavity;
• (d) first conduit means having one end thereof in communication with said chamber and the other end thereof in communication with said cavity;
• (e) second conduit means having one end thereof in communication with said intake opening and the other end thereof in communication with said cavity;
• and
• (f) a filter mounted in said cavity between said other ends of said first and second conduit means, whereby energization of said motor causes a flow of air from said chamber through said filter and into said tool housing.