Patent GB-1364145-A (GB)
Title: Spin welding apparatus
IPC: B29C65/78
Filed: 1972-10-17
Abstract: 1364145 Packaging KOEHRING CO 17 Oct 1972 47722/72 Heading B8C [Also in Division B5] Apparatus for spin welding together two container parts 4, 6 comprises a pedestal assembly 112 to receive a part 6 which pedestal 112 includes a stage portion 122<SP>1</SP> to mate with a recess in the part 6, a protruding lip portion 124 projecting from the portion 122<SP>1</SP> to support the part 6, and an angularly disposed surface 128 interconnecting the portions 122<SP>1</SP>, 124. In apparatus for making, filling and closing milk bottles, thermoplastic container parts 4, 6 are spin welded together in a unit 32 by being received on cylindrical mandrels 60, 62 which move about a circular path during one angular portion of which a belt 34 rotates the lower mandrels 62 whilst the parts 4, 6 are brought into contact. The upper parts 4 are supplied by a unit 12, Fig. 2, holding eight vertical stacks thereof  arranged in a circle and supplied through funnels at the top of the unit and the lower parts 6 are supplied by a similar unit 24. At locations 20, 28, a part 4 and a part 6, respectively, are removed from each stack and are transferred to a dual level star wheel 18 which delivers them to the unit 32. Subsequent to spin welding, the containers are transferred individually to a filler unit 38 by a star wheel 36. Filled containers are transferred to a unit 46 for heat sealing caps thereto which caps have been loosely placed thereon by a device 42 receiving caps from a mechanism 44 whilst the containers are carried by a star wheel 40. A star wheel 48 transfers the filled and capped containers to a delivery conveyer 50. The unit 32 comprises a central hollow shaft 36 drivable by gears 72, 74 about a stationary shaft 84. The mandrels 60, 62 are movable vertically on shafts 94, 96 extending from supports 98, 100 carried by the shaft 76. Vertical movement of the mandrels 60, 62 is achieved by rods 102, 104 having cam followers 106, 108 to travel within annular cam tracks 88, 92. Bearings 111 are interposed between each mandrel 62 and its shaft 96. When a mandrel 60 surrounds a part 4, suction is applied to a central opening 116 through a port 114 connected to a conduit 86 to hold the part therein. A stage 118 slides relative to the shaft 94 to aid separation of the welded container from the mandrel 60. An extra increment of relative movement may be accomplished by a follower 122 connected to a rod 120 carrying the stage 118. The follower 122 is movable by a cam track 124. The pedestal 112 is carried by the shaft 96 and comprises a flat stage portion or upper surface 122<SP>1</SP> conforming to a central recess in the part 6. A substantially flap lip 124 extends outwardly from the surface 122<SP>1</SP> via an annular inclined surface 128 to support the outer edges of the part 6. Suction may be applied through an opening 132 to hold the part 6 during spin welding. The pedestal 112 co-operates with the mandrel 62 during spinning, vertical ribs on the part 6 mating with flutes within the mandrel 62. During the spinning of the mandrel 62 by the belt 34, the mandrel is raised to press the part 6 into contact with the part 4. The mandrel 62 lifts the pedestal 112 clear of the shaft 96, the edge 130 of the lip 124 engaging the inner surface of the mandrel 62 just prior to spinning to lift a pedestal stem 134 slightly. The stem 134 moves in a slot 136 in the shaft 96 and an 0-ring 138 prevents the pedestal leaving the shaft during spinning. In a modification, Fig. 4C (not shown), the lip (126) is slightly inclined upwardly and away from the central axis of the pedestal (112).