Method and apparatus for producing a foam from a molten thermoplastic material
AssigneeNordson Corporation
InventorsHarald Pleuse, Peter E. Muller
Life of this patent
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Abstract
A method and apparatus for creating molten thermoplastic material foam by separately pressurizing the molten thermoplastic material and a gas and by delivering that material and gas sequentially to a premixing chamber, through a sintered metal insert and a post mixing chamber, to a discharge orifice of a spray nozzle. The apparatus for practicing this method comprises a nozzle assembly, including a nozzle adaptor and a nozzle, the adaptor of which has flow passages for delivering the pressurized gas and molten material to a premixing cavity and subsequently to and through a sintered metal insert contained within the nozzle.
Claims6
A method of creating a molten thermoplastic material foam which comprises:
- pressurizing molten thermoplastic material to a pressure substantially greater than atmospheric pressure, separately pressurizing gas to a pressure greater than the pressure of the pressurized molten thermoploastic material, delivering the pressurized molten thermoplastic material and gas through separate passages to a first internal premixing chamber of a nozzle assembly, which nozzle assembly has a discharge orifice,
- passing the premixed mixture of molten thermoplastic material and gas through a sintered insert contained within a second chamber of said nozzle assembly, and
- passing the gas and liquid mixture from the second chamber to atmosphere through said discharge orifice of said nozzle assembly whereby a foam of said molten thermoplastic material is generated.
A method of creating a molten thermoplastic material foam which comprises:
- pressurizing molten thermoplastic material to a pressure of several hundred pounds per square inch,
- separately pressurizing gas to a pressure greater than the pressure of the pressurized molten thermoplastic material,
- delivering the pressurized molten thermoplastic material and pressurized gas through separate passages to a first internal premixing chamber of a nozzle assembly, which nozzle assembly has a discharge orifice,
- passing the premixed mixture of molten thermoplastic material and gas through a sintered insert contained within a second chamber of said nozzle assembly, and
- passing the gas and liquid mixture from the second chamber to atmosphere through said discharge orifice of said nozzle assembly whereby a foam of said molten thermoplastic material is generated.
Dependencies are inferred from the claim text.