US 6,296,726 B1 · Method and apparatus for spin welding container closures

Abstract

Sealed synthetic resin containers are spin welded by bringing opposed, generally complimentary horizontal mating surfaces of the lid and bowl into contact under a predetermined axial pressure and rapidly accelerating rotation of the lid relative to the bowl while maintaining substantially the axial pressure to produce melting of the mating surfaces until a desired torque value is attained. Thereafter, the rotation of the lid is immediately decelerated to terminate the rotation and allow the mating surfaces to bond. Generally, the torque is monitored repeatedly during the accelerating rotation until a plateau is reached and the accelerating step is continued for at least 50 milliseconds thereafter.

Claims18

Dependent claims

The method of making sealed synthetic resin containers comprising:

(a) molding thermoplastic synthetic resin into bowls and lids therefor, said lid and bowl having substantially complimentary mating surfaces extending about the periphery thereof;
(b) filling one of said bowls with product;
(c) bringing opposed, generally horizontal mating surfaces of said lid and bowl into contact under a predetermined axial pressure while gripping said product filled bowl and lid securely;
(d) rapidly accelerating rotation of said lid relative to said bowl while maintaining substantially said axial pressure to produce melting of said mating surfaces until a desired torque value is attained;
and
(e) then immediately decelerating said rotation of said lid to terminate said rotation and allow said mating surfaces to bond.

3 more elements

Dependencies are inferred from the claim text.

Method and apparatus for spin welding container closures

Life of this patent

Method and apparatus for spin welding container closures

Life of this patent

Abstract

Claims18