Abstract: A cutting tool mechanism and cutting tool (11) including the mechanism (31), for cutting hard material such as concrete and stone is disclosed. The tool (11) has one or two blades (23), (25) each driven by a mechanism (31). Each mechanism (31) has an input coupling 35 for transmission of rotary motion from a motor, and an output coupling (141), (143) to transmit resultant orbital, oscillatory or impact motion to the blade (23), (25). A suspension or sliding coupling located between the output coupling (141), (143) and the blade (23), (25), is provided, through which motion to the blades is transmitted. The suspension or sliding coupling absorbs impacts of the blades with the material being cut, rendering the tool more controllable.

Abstract: A cutting apparatus of a type having two juxtaposed blades 1 and 2 with each having an outermost cutting edge with teeth 12 and 13, with retention and driving of the blades adapted to effect an oscillatory motion to each of the cutting edges, characterized in that there are means to resist resonant spreading between the blades 1 and 2 when cutting which are that there is a first of the blades 1 having a first portion supported by the first blade with a part 15 which is positioned behind a part 18 of the other blade, and a second blade 2 includes a portion with the part 18 which is positioned behind the part of the first said blade.