DEVICE FOR ULTRASONIC SEALING UNIT Russian patent published in 2001 - IPC

FIELD: packing devices. SUBSTANCE: invention relates to device used in drive unit of ultrasonic sealing arrangement. Drive unit of this type consists of several piezoelectric ceramic plates 3 with intermediate current-conducting metal sheets 4 connected with ac source. Drive unit has also counterweight 5 and screw clamp 6 to press ceramic plates 3, metal sheets 4 and counterweight 5 to each other. Screw clamp stationary holds drive unit in sealing unit. Sealing unit has homogeneous housing 13 consisting of reverse-action housing enclosing drive unit, central plane 10 with end face for anchor attachment and bell with longitudinal narrow sealing surface. Device includes also gasket 12 arranged to form spacing between housing 13 of sealing unit 1 and ceramic plates 3. Gaskets 12 permits oscillating of ultrasonic sealing unit, but it precludes action of residual bending stresses on drive unit. Thickness of gasket 12 can be chosen to adjust amplitude of sealing unit within preset limits. Such design of drive unit of ultrasonic sealing unit makes it possible to reduce residual bending loads in central plane to such value at which they are not transmitted to sensitive ceramic plates. Provision is made for checking all manufactured sealing units as a result of which all they operated at the same amplitude. EFFECT: enhanced reliability. 8 cl, 3 dwg