Abstract: A power tool system includes a tool body in which an activation switch (12) controls a motor (20). A plurality of interchangeable tool heads (50) are able to be accepted by the power tool in order to provide a dedicated tool. A releaseable lock-off mechanism (90) is incorporated in the tool body which restrains actuation of the activation switch (12) when none of the tool heads (50) is present.

Abstract: A power tool comprises a body (14) having a motor (22) with an output. A detachable tool head (50) is engageable with the motor output wherein the motor output has a first engagement member (32) for complimentary engagement with a second engagement member (62) on the tool head drive. The first engagement member (32) is recessed within the body (14) and accessible through an aperture (44) therein. And the second engagement member (62) is recessed within the tool head (52) and accessible through a second aperture therewithin.

Abstract: A lock-off mechanism (80) for a power tool (2) comprises a longitudinally extended locking member (80) pivotally mounted within the power tool and having one end (86) resiliently biased into engagement with a power switch (12). The mechanism further comprising an actuation member extending substantially perpendicular to the locking member (80) so as to be displaceable transversely with respect to the locking member (80) and engagable therewith to effect cam engagement between a cam surface (300) of the actuation member and a cam surface (90) of the lever member (80) upon such transverse displacement of the actuation member, so as to pivotally displace the locking member (80) out of engagement with the switch (12).