Abstract: An electric cutting tool has a body, a chuck at an end of the body for attaching a cutting implement having a rear end including a recess, and a drive mechanism for driving the chuck to slide in reciprocation for operating the cutting implement. The chuck has a gap for receiving the rear end of the implement, an internal multi-part fixing mechanism for engaging the recess of the cutting implement in the gap, and an outer cylinder having an inner cam surface for acting upon the fixing mechanism. The cylinder is manually rotatable between a locked position in which the cam surface presses the fixing mechanism tight against the recess in the gap to fix the cutting implement in place and an unlocked position in which the fixing means is released from the cutting mechanism. The fixing mechanism includes two discrete balls.

Abstract: A power hand tool includes a body and an electric motor in the body and having a shaft for driving a connector for connecting and driving a cleaning/polishing implement. An enclosure encloses the motor for protection against intrusion of a liquid, and includes a thermally conductive end cap that is exposed outside of the body. A thermal conductor in contact with a metal casing of the motor and the end cap conducts heat from the motor to the end cap for heat dissipation.

Abstract: A battery pack (10) for a power tool (T) includes a casing (11/12) housing rechargeable cells (24). A receiving bay (18) in the casing (11/12) receives slide-in parts of the power tool (T), or of a recharging stand (20), to retain the battery pack (10). A pair of primary electrical contacts (16) is located in or adjacent the receiving bay (18). A recess (15) opens into the receiving bay (18). A supplementary electrical contact (17) is located within the recess (15), and a user-manipulable catch (23) is also located therein alongside the supplementary contact (17). That is, a single recess (15) houses both the supplementary contact (17) and the mechanical catch (23). The supplementary contact (17) is usable when recharging the battery (24) to relay battery temperature information to a recharging stand (20), but has no function when the battery pack (10) is attached to the power tool (T).

Abstract: A drill bit capable of axial cutting as well as side cutting, having a generally cylindrical elongate body with a bit diameter, includes a frontmost drilling end for axial cutting, a cutting section extending from the drilling end for side cutting, and a shank extending from the cutting section. The cutting section is helically cut at a helix angle of substantially 15°±2° to form one pair of diametrically opposite helical flutes whose outermost edges are sharpened to form respective cutting edges, arranged around a solid central core whose diameter is substantially directly proportional to the bit diameter. The length of the cutting edges in the axial direction of the drill bit body is calculated according to the formula: Cutting Edge=Bit Diameter×&pgr;×Cc/Tan (Helix Angle), Cc being a constant in a range from 0.85 to 0.90.

Abstract: A drill bit capable of axial cutting as well as side cutting, having a generally cylindrical elongate body of a bit diameter, which comprises a frontmost drilling end for axial cutting, a cutting section extending from the drilling end for side cutting, and a shank behind the cutting section. The cutting section is helically cut at a helix angle of substantially 15°±2° to form one pair of diametrically opposite helical flutes whose outermost edges are sharpened to form respective cutting edges, around a solid central core whose diameter is substantially directly proportional to the bit diameter. The length of the cutting edges in the axial direction of the drill bit body is calculated according to the formula: Cutting Edge=Bit Diameter×&pgr;×CC/Tan(Helix Angle), CC being a constant of a value in the range substantially from 0.85 to 0.90.