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.
A releasable coupling includes a male coupling portion having a frustoconical male plug portion, and a female coupling portion having a frustoconical female socket portion. The male and female coupling portions are locked together and unlocked by a bidirectional rotatable cam ring which drives one or more balls between the male and female coupling portions.
