# US 9,038,672 B2 · Hollow article of variable wall structure density

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- Number: US 9,038,672 B2
- Document ID: US9038672B2
- Status: Granted
- Kind: B2
- Application number: 13/990,776
- Filed: 2011-12-01
- Published: 2013-10-03
- Granted: 2015-05-26
- Earliest claimed: 2010-12-02
- Assignees: Salflex Polymers Ltd.
- Applicants: Danny Cacciacarro
- Inventors: Danny Cacciacarro
- Web page: https://patentgrep.com/patent/US9038672B2

## CPC

- F16L 9/133: the walls consisting of two layers
- B29C 44/04: consisting of at least two parts of chemically or physically different materials, e.g. having different densities
- B29C 49/0005: {characterised by the material}
- B29C 49/04114: {for keeping constant thickness}
- B29C 49/22: using multilayered preforms or parisons
- B32B 3/263: {characterised by a layer having non-uniform thickness}
- B32B 27/065: {of foam}
- B29C 48/0012: {combined with shaping by internal pressure generated in the material, e.g. foaming}
- B29C 48/13: Articles with a cross-section varying in the longitudinal direction, e.g. corrugated pipes
- B29C 48/21: the layers being joined at their surfaces
- B29C 49/0015: {Making articles of indefinite length, e.g. corrugated tubes}
- B29C 49/0021: {using moulds or mould parts movable in a closed path, e.g. mounted on movable endless supports}
- B29C 2049/222: {only parts of the preforms or parisons are layered}
- B29C 2049/609: {Two or more blow-needles}
- B29C 2949/072: having variable wall thickness
- B29C 2949/3004: having longitudinally different components within one layer, e.g. tubes with longitudinal stratified layering
- B29K 2023/06: {PE, i.e. polyethylene}
- B29K 2023/12: {PP, i.e. polypropylene}
- B29K 2071/12: {PPO, i.e. polyphenylene oxide; PPE, i.e. polyphenylene ether}
- B29K 2077/00: Use of {PA, i.e.} polyamides, e.g. polyesteramides {or derivatives thereof}, as moulding material
- B29K 2081/04: {Polysulfides, e.g. PPS, i.e. polyphenylene sulfide or derivatives thereof}
- B29K 2105/04: cellular or porous
- B29L 2023/003: {having irregular or rough surfaces}
- B29L 2023/004: {Bent tubes (for use as pipe couplings B29L2031/24)}
- B32B 2597/00: Tubular articles, e.g. hoses, pipes
- Y10T 428/1376: Foam or porous material containing
- F16L: PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- B29C: SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING (making preforms B29B11/00; making laminated products by combining previously unconnected layers which become one product whose layers will remain together B32B37/00 - B32B41/00)
- B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B29K: INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR {MOULDS, } REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29L: INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
- Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION

## Abstract

A molded thermoplastic article including a hollow body is provided, the article comprising a first layer, and a foamed second layer, the first layer and foamed second layer defining a wall structure, the foamed second layer having a lighter density relative to the first layer. In the wall structure, the ratio of the first layer to foamed second layer varies along the length of the article.

## Claims

### Claim 1

A molded thermoplastic article including a hollow body, the article comprising:
a first layer;
a foamed second layer;
wherein the article comprises a wall structure incorporating said first layer and said foamed second layer, said foamed second layer having a lighter density relative to said first layer, and
wherein a ratio of a thickness of said first layer to a thickness of said foamed second layer varies along the length of said article, and
wherein along the length of the article, the quantitative measure of said first layer and said foamed second layer provides the wall structure with a generally constant thickness along the length of the article.

### Claim 2 (depends on 1)

The molded thermoplastic article according to claim 1, wherein said foamed second layer is foamed using a chemical or physical blowing agent.

### Claim 3 (depends on 1)

The molded thermoplastic article according to claim 1, wherein said ratio is increased at regions of the article requiring increased wall structural density.

### Claim 4 (depends on 1)

The molded thermoplastic article according to claim 1, wherein said ratio is decreased at regions of the article requiring decreased wall structural density.

### Claim 5 (depends on 1)

The molded thermoplastic article according to claim 1, wherein said first layer is an outside layer, and said foamed second layer is an inside layer.

### Claim 6 (depends on 1)

The molded thermoplastic article according to claim 1, wherein said first layer is an inside layer, and said foamed second layer is an outside layer.

### Claim 7 (depends on 1)

The molded thermoplastic article according to claim 1, wherein the article is an automotive HVAC or air induction duct.

### Claim 8 (depends on 7)

The molded thermoplastic article according to claim 7, wherein said duct has an increased ratio of said first layer to said foamed second layer in regions of said duct requiring increased wall structure density.

### Claim 9 (depends on 8)

The molded thermoplastic article according to claim 8, wherein said regions requiring increased wall structure density include at least one of end cuffs, mounting tabs, and bellows.