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 ▼

A method of inertial spinwelding of a thermoplastic container bottom having an axially extending peripheral surface receivable with a press fit within one end of an open-ended cylindrical container body, said method comprising: releasably mounting a thermoplastic container bottom having an axially p

A method of inertial spinwelding of a thermoplastic container bottom having an axially extending peripheral surface receivable with a press fit within one end of an open-ended cylindrical container body, said method comprising: releasably mounting a thermoplastic container bottom having an axially projecting peripheral flange member adapted for tight-fitting engagement in a cylindrical body member, and an open-ended cylindrical paperboard container body, on axially aligned, opposed mandrels, at least one of which is rotatable mandrel; temporarily engaging said rotatable mandrel with a rotary drive to bring it up to a predetermined rotational speed; disengaging said rotary drive and allowing said rotating mandrel to continue rotating; and, moving the two mandrels axially toward each other while said mandrel is rotating, and seating said bottom in one end of said body, thereby spinwelding said bottom into said body; wherein the mounting of said body on its mandrel further comprises the steps of radially contracting expandable and contractable body engaging means on said mandrel, locating the body over said body engaging means, and radially expanding the inserted body engaging means to conform the interior surface of said body to a cylindrical surface of a predetermined desirable diameter.