Multi-process molding method and article produced by same

• US 6,475,424 B1
• Filed: 05/14/1998
• Issued: 11/05/2002
• Est. Priority Date: 05/14/1998
• Status: Expired due to Fees

• Current Assignee: Magna International Incorporated
• Original Assignee: Cambridge Engineering Incorporated
• Inventors: van Manen, Dick T.
• Primary Examiner(s): McDowell, Suzanne E.
• Application Number:
  US09/079,096
• Time in Patent Office: 1,636 Days
• Field of Search: 264/513, 264/512, 264/515, 264/255, 264/259, 264/271.1, 264/279, 264/28, 264/526, 264/331.16
• US Class Current: 264/513
• CPC Class Codes: B29C 2045/1445 injecting a part onto a blow moulded object
• CPC Class Codes: B29C 2791/001 Shaping in several steps
• CPC Class Codes: B29C 45/14836 Preventing damage of inserts during injection, e.g. collapse of hollow inserts, breakage B29C45/14434 takes precedence
• CPC Class Codes: B29C 45/7207 of the moulded articles
• CPC Class Codes: B29C 49/04 Extrusion blow-moulding
• CPC Class Codes: B29C 67/246 Moulding high reactive monomers or prepolymers, e.g. by reaction injection moulding [RIM], liquid injection moulding [LIM] casting monomers B29C39/006, mixing construction B29B7/74
• CPC Class Codes: B29K 2075/00 Use of PU, i.e. polyureas or polyurethanes or derivatives thereof, as moulding material
• CPC Class Codes: B29L 2022/00 Hollow articles tubular articles B29L2023/00; pneumatic tyres B29L2030/00

Abstract

A method of manufacturing a multi-layered plastic manifold (10) including molding an outer layer (22) of the manifold (10) about a blow molded core insert (20). The outer layer (22) is molded by either a thermoplastic injection molding process or a urethane casting process. While the outer layer (22) is being molded, the pressure and temperature within the core insert (20) are controlled to preserve the structural integrity of the core insert (20).

Claims

1. A method of manufacturing a molded article comprising the steps of:

inflating a blow moldable article to form a blow molded article having an outer surface;

inserting the blow molded article within an interior cavity of a mold;

inserting moldable fluid material within the interior cavity of the mold adjacent the outer surface of the blow molded article;

during said step of inserting the moldable fluid material, applying cooling fluid within the blow molded article at a temperature sufficient to maintain the shape of the blow molded article; and

selecting the temperature of the cooling fluid based on the melting temperature of the blow molded article and the heat transfer from the moldable fluid material to prevent the blow molded article from losing structural integrity due to the heat transfer from the moldable fluid material.

2. The method as defined in claim 1, further comprising:

inserting the blow moldable article within an interior cavity of a first mold; and

prior to said step of inserting the moldable fluid material, inserting the blow molded article within an interior cavity of a second mold wherein the interior cavity substantially envelops the blow molded article and is larger than the interior cavity of the first mold.

3. The method as defined in claim 1 wherein the blow moldable article and the moldable fluid material comprise a thermoplastic material.

4. A The method as defined in claim 1, further comprising forming the moldable fluid material into an outer layer of a manifold and forming the blow moldable article into an inner layer of a manifold.

5. The method as defined in claim 1 wherein the moldable fluid material comprises a urethane resin.

6. The method as defined in claim 5 further comprising adding a curing catalyst to the urethane resin to cause the resin to cure in an exothermic chemical reaction.

7. The method as defined in claim 6 further comprising selecting the temperature of the cooling fluid based on the melting temperature of the blow molded article and the heat transfer from the urethane resin during exothermic curing of the urethane resin.

8. The method as defined in claim 1 further comprising:

injecting the moldable fluid material within the interior cavity of the mold; and

applying pressurized cooling fluid within the blow molded article at a pressure sufficient to maintain the shape of the blow molded article against the inwardly directed force of the moldable fluid material injected into the mold.