Patent ID: 7267535

Claim:
An extruding apparatus which extrudes continuous length of hollow plastic product, said apparatus comprising an extruder which feeds molten plastic through die equipment to a mold tunnel formed by side by side moving mold blocks, the plastic product being shaped within the mold tunnel, said apparatus including means to provide air turbulence to assist in setting shape of the product, said means comprising a powered air moving member which is located internally of the product in the mold tunnel, a power source for powering said air moving member, said power source being located externally of the mold tunnel, and a power transfer member which feeds from said power source through said die equipment to said air moving member; and wherein said air moving member is a rotor having a plurality of blades with each blade having inner and outer blade portions, each of said blades being mounted at said inner blade portions to a common mounting shaft for rotating said blades, said inner and outer blade portions being arranged such that said outer blade portions provide greater positive air pressure than said inner portions to produce a low pressure air draw at said inner blade portions.