Carton sealing apparatus

Abstract

Carton sealing apparatus for sealing a rectangular end closure of a thermoplastic coated paperboard carton by ultrasonic vibrations. The apparatus includes an anvil, or backup member, and an ultrasonic vibrating tool. The mandrel is received in the carton with the end closure to be sealed folded against the smooth end surface thereof. The ultrasonic vibrating tool engages the end closure on the opposite side thereof from the mandrel, and, when energized, generates heat sufficient to cause the thermoplastic coating of the paperboard to flow and weld the layers of the end closure together. Ribs project from the end surface of the vibrating tool to provide a sealing pattern of "bow-tie" configuration, the ribs having various heights with respect to the end surface of the vibrating tool to accommodate changes in the number of layers of paperboard at the different areas on the end closure.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows: 
     
       1. A carton sealing vibrating tool for ultrasonically sealing an end closure of a thermoplastic coated paperboard carton comprising: a body having an end surface with a ribbed formation projecting therefrom, said ribbed formation including a pair of oppositely disposed sets of concentric triangular enclosures. 
     
     
       2. A carton sealing vibrating tool as claimed in claim 1 wherein said ribbed formation further includes a pair of oppositely disposed V-shaped ribs between the opposed apices of said triangular enclosures. 
     
     
       3. A carton sealing vibrating tool as claimed in claim 2 wherein said ribbed formation further includes a pair of triangular projections, one of which is located between the legs of one of said V-shaped ribs, and the other of which is located between the other of said V-shaped ribs. 
     
     
       4. A carton sealing vibrating tool as claimed in claim 3 wherein said triangular enclosures each have a base leg and a pair of side legs, and wherein said base legs and side legs have reduced height portions with respect to said end surface. 
     
     
       5. A carton sealing vibrating tool as claimed in claim 4 wherein said V-shaped ribs and triangular projections have the same height with respect to said end surface as said reduced height portions of said legs. .Iadd. 6. A carton sealing vibrating tool for sealing an end closure of a thermoplastic coated paperboard carton, said tool comprising: a body having an end surface with a formation projecting therefrom, said projecting formation of the end surface including a pair of triangles arranged in an opposed relationship and having respective apices located adjacent each other so as to form a bow-tie configuration, and each projecting triangle having a recessed surface portion enclosed thereby such that there are at least two recessed surface portions located on opposite sides of the adjacent apices of the triangles. .Iaddend..Iadd. 7. A tool as claimed in claim 6 wherein the triangles of the projecting formation on the end surface have the apices thereof spaced from each other and the end surface including projecting portions extending between the triangles at the spaced apices of the triangles. .Iaddend..Iadd. 8. A tool as claimed in claim 7 wherein the body end surface projecting portions between the triangle apices comprise V-shaped ribs. .Iaddend. .Iadd. 9. A tool as claimed in claim 6 wherein the body end surface has edges defining a rectangular shape thereof, and said triangles having respective legs extending along opposite edges of the end surface. .Iaddend. .Iadd. 10. A carton sealing vibrating tool for sealing an end closure of a thermoplastic coated paperboard carton, said tool comprising: a body having an end surface including edges forming a rectangular shape, said body end surface including a formation projecting therefrom with a pair of triangles arranged in an opposed relationship, the triangles having respective legs extending along opposite edges of the end surface and also having legs extending inwardly from the legs along the opposite edges to define respective apices located adjacent each other at the center of the end surface so as to form a bow-tie configuration, and the body end surface having at least two recessed surface portions respectively located between the center of the end surface and the opposite edges thereof along which said triangle legs extend so as to be enclosed by the triangles. .Iaddend.