초록 ▼

A thermoplastic container bottom is inertially spin welded into the interior of a cylindrical container body of paperboard internally lined with a layer of thermoplastic material. A body supporting mandrel has an expansible body engaging portion which is inserted into the body and subsequently expan

A thermoplastic container bottom is inertially spin welded into the interior of a cylindrical container body of paperboard internally lined with a layer of thermoplastic material. A body supporting mandrel has an expansible body engaging portion which is inserted into the body and subsequently expanded to define a cylindrical surface of a diameter exactly equal to that of the specified internal diameter of the body. A seating member at the end of the body supporting mandrel establishes the depth to which the container bottom is inserted into the body and is provided with a low-friction projecting resilient member which contacts the rotating bottom.

대표청구항 ▼

Spin welding apparatus comprising upper and lower mandrel means mounted for vertical movement toward and away from each other along a common vertical axis, said upper mandrel means being adapted to releasably support an open ended cylindrical container body and said lower mandrel means being adapted

Spin welding apparatus comprising upper and lower mandrel means mounted for vertical movement toward and away from each other along a common vertical axis, said upper mandrel means being adapted to releasably support an open ended cylindrical container body and said lower mandrel means being adapted to releasably support a container bottom of thermoplastic material having an axially upwardly projecting peripheral flange insertable into said container body with a press fit, first drive means for driving at least one of said mandrel means in rotation about said vertical axis relative to the other mandrel means, and second drive means for driving said mandrel means in movement along said vertical axis to seat said container bottom within said container body while said mandrel means are rotating relative to each other to insert and frictionally weld said container bottom in said container body; with radially expansible and contractable body engaging means mounted on the lower end of said upper mandrel means in symmetrically disposed relationship about said vertical axis, said engaging means being normally disposed in a contracted position wherein said engaging means may be axially inserted into a container body, expanding means for radially expanding said engaging means to an expanded position wherein the radially outer surfaces of said expanding means lie on a common cylindrical surface having a diameter equal to the specified internal diameter of said container body and further comprising a seating member mounted at the lower end of said upper mandrel means and engagable with said container bottom to establish the depth to which said container bottom is inserted within said container body by operation of said second drive means.