The present invention relates to improved ultrasonic cutting devices and methods.
In a prior art ultrasonic cutting device and method, a cutting blade is mounted on an ultrasonic vibrating device in a manner such that the blade lies in a plane containing the longitudinal axis of vibrations generated by the ultrasonic vibrating device. In operation, the blade is vibrated in its plane and is moved through an article to be cut in that plane.
Difficulty is experienced using such cutting devices and methods, in that the depth of cut which is attainable is limited. For this reason, ultrasonic cutting has in general been limited to thin articles, such as paper, cloth and thin plastic sheets. A significant problem exists in cutting blocks of substantial depth, and/or in providing a number of parallel cuts simultaneously. Difficulty is also experienced in cutting materials which are brittle, such as honeycomb or crystalline materials.
In European patent Application 0353415A, the entirety of which is hereby incorporated herein by reference, there is described a method and apparatus for cutting an article wherein a cutting blade is mounted on an ultrasonic vibrating device in a manner such that the blade lies in a plane extending transverse, preferably at right angles, to the longitudinal axis of vibrations generated by the ultrasonic vibrating device. In operation, the vibrated cutting blade moves back and forth, transverse to the plane in which it is passed through the article, thereby effecting a removal of the material of the article along the line of cut. In one embodiment, the ultrasonic vibrating device comprises one or more vibrated support members, each support member supporting a plurality of cutting blades, each blade being secured to a single support member at its centre.