Cutting apparatus

A cutting tool having a body, the first blade secured at a first location to a link secured to the body and arranged to allow constrained relative motion to the body, the first blade being further secured to the body by a first pivot connection, which itself is secured to a rotatable drive adapted to provide an oscillatory motion to the blade in a direction co-planar with the plane of the blade relative to the body, the first blade having an outer cutting edge with teeth, the cutting edge being spaced apart from an axis of the rotatable drive, and spaced apart further from said first location, the cutting edge being of convex arcuate shape having an approximate radius with a radial centre being an axis through an outermost position of the central axis of its connection with the rotatable drive, and its extent being from a position approximately aligned with the said first location and the said axis through an outermost position of the central axis of its connection with the rotatable drive, and extending around to approximately a position where it is aligned at approximately 45° to said first radius, a second blade secured at a second location to a second link secured to the body and arranged to allow constrained relative movement to the body, the second blade being further secured to the body by a second pivot connection which itself is secured to a rotatable drive adapted to provide an oscillatory motion to the blade in a direction parallel with the plane of the blade relative to the body, the second blade having an outer cutting edge with teeth, the cutting edge being spaced apart from the axis of the rotatable drive, and spaced apart further from the said second location, the cutting edge being of convex arcuate shape having an approximate radius with a radial centre being the axis through an outermost position of the central axis of its connection with the rotatable drive, and its extent being from a position approximately aligned with the said second location and the said axis through an outermost position of the central axis of its connection with the rotatable drive, and extending around to approximately a position where it is aligned at approximately 45° to the said second radius, the first and second blades being shaped and supported relative to the body so that each cutting surface is restrained to move in an elliptical path the one being with an action that is out of phase compared to the action of the other, and having the cutting edges in a co-operatively mutually aligned cutting relation, a member secured to the body and extending to provide a first anchor locator which is positioned to be further out from the body than the respective cutting edges of the respective adjacent blades.

A cutting tool comprising two juxtaposed cutting members each having a tooth cutting edge of a substantially same shape and extent, each of said cutting members having a drive portion extending in a direction lateral to the cutting edge, said drive portions being in a juxtaposed relation;

• a. a drive means adapted for coupling to a motor and operatively interacting with each said drive portion to impart thereto an eccentric movement in a plane of each respective said drive portion about a common axis, the eccentric movement imparted to the respective drive portions being equal and angularly out of phase;
• and
• b. means to restrain movement of the respective drive portions at a specific location spaced from said common axis to an approximately linear movement in a direction radial to the common axis and to angular movement about a respectively pivot axis parallel to said common axis, whereby in response to activation of the drive means, the cutting edge of each cutting member prescribes, in a plane of the cutting member, simultaneous oscillatory movements in the direction of the cutting edge and in a direction substantially at right angles to the cutting edge, the corresponding movements of the respective cutting members being outer phase, and the teeth of the cutting edge being adapted to each cut when moving individually in one direction in the direction of the extent of the cutting edge, and a member located to a side of the respective cutting members and providing an anchor locator shape
• which is positioned beyond the position of the cutting edges of each respective blade.