Plastic material extrusion head

Claim 1

A PLASTIC MATERIAL EXTRUSION HEAD COMPRISING AN ENCLOSURE HAVING A PLENUM CHAMBER GENERALLY IN THE FORM OF A PART OF A CIRCULAR DISC, SAID CHAMBER HAVING A CURVED EDGE THROUGHOUT A SUBSTANTIAL PART OF ITS PERIPHERAL ANGULAR EXTENT AND SPANNING A PREDOMINANT PART OF THE WIDTH OF THE CHAMBER, THE CHAMBER HAVING BROAD FORWARD AND REAR SURFACES FORMED BY FORWARD AND REAR WALLS OF THE ENCLOSURE, A PASSAGE FOR DELIVERING PLASTIC MATERIAL UNDER PRESSURE TO THE CHAMBER, SAID PASSAGE ENTERING THE CHAMBER ADJACENT THE CURVED EDGE OF THE CHAMBER, A PLASTIC MATERIAL DISTRIBUTING CHANNEL IN AT LEAST ONE OF SAID SURFACES OF THE CHAMBER, AND A BROAD ORIFICE IN THE CHAMBER REMOTE FROM THE CHANEL, SAID CHANNEL DIRECTLY COMMUNICATING WITH THE INNER END OF THE DELIVERY PASSAGE, THE CHANNEL GENERALLY PARALLELING THE CURVED EDGE OF THE PLENUM CHAMBER, THE CHANNEL BEING DEEPEST AT THE ZONE THEREOF NEAREST THE INNER END OF THE PASSAGE AND PROGRESSIVELY DECREASING IN DEPTH FROM ITS ZONE OF COMMUNICATION WITH THE DELIVERY PASSAGE, SAID CHANNEL DISTRIBUTING PLASTIC MATERIAL ACROSS THE WIDTH OF THE CHAMBER FOR FORWARDING SUCH MATERIAL FROM THE CHAMBER IN A DIRECTION AWAY FROM THE CURVED EDGE OF THE CHAMBER.