Method of Manufacturing Spa/tub Shell with Improved Spa/tub Jet Interface

• US 20140102634A1
• Filed: 10/12/2012
• Published: 04/17/2014
• Est. Priority Date: 10/12/2012
• Status: Abandoned Application

• Current Assignee: Lmi Ip, LLC
• Original Assignee: LMI Roto, LLC
• Inventors: Harder, Gary
• Application Number:
  US13/650,577
• Publication Number:
  US 20140102634A1
• Time in Patent Office: Days
• US Class Current: 156/253
• CPC Class Codes: B29C 33/0033 constructed for making articles provided with holes
• CPC Class Codes: B29C 41/04 Rotational or centrifugal casting, i.e. coating the inside of a mould by rotating the mould
• CPC Class Codes: Y10T 156/1057 Subsequent to assembly of laminae

Abstract

A method and apparatus for forming a tubular orifice formed/added to a wall of a molded product such as a tub, spa, hot tub, boat hull, tank, vat, trough, etc. The resulting tubular orifice has a smooth, regular, tubular inner wall that seals well with accessories that have tubular interface sections that fit within the tubular orifice and seal using one or more o-rings. The orifice is formed around an insert that is removably held to an inside wall of a mold by, for example, magnets during rotational molding, thereby enabling extraction of the molded product from the mold as the inserts separate from the inside wall as the molded product is extracted.

Claims

1. A method of forming an orifice in a wall of a molded product, the method comprising:

removably affixing an insert on an inside wall of a mold;

applying a structural material to the mold, forming the molded product;

allowing the structural material to set;

separating the molded product from the mold, whereas the insert separates from the mold by way of the insert being removably affixed; and

removing the insert from the molded product.

2. The method of claim 1, whereas the insert is removably affixed to the inside wall of the mold by magnetic force.

3. The method of claim 1, wherein the molded product is a spa.

4. The method of claim 1, wherein the molded product is a bath tub.

5. The method of claim 1, wherein the structural material is a resin and the step of applying the structural material to the mold includes heating the mold while rotating the mold.

6. The method of claim 5, wherein the insert has two parts, a first part having properties in which the structural material adheres to the first part and a second part in which the structural material does not substantially adhere to the second part.

7. The method of claim 6, wherein the first part has a higher level of heat conduction, thereby heating enough as to collect the material and the second part has a lower level of heat conduction, thereby not heating sufficiently as to collect substantial amounts of the material.

8. The method of claim 6, wherein the molded part is a tub/spa, the first part is a disk comprising a metal and having a first diameter, and the second part is a disk made of plastic and having a diameter that is greater than the first diameter.

9. The method of claim 8, wherein the metal is aluminum and the plastic is polytetrafluoroethylene (Teflon).

10. The method of claim 1, wherein the structural material is fiberglass and the step of applying the structural material to the mold further comprises:

applying a gel coat to the mold before the step of applying the structural material to the mold;

allowing the gel coat to at least partially set;

affixing a first end of one or more tubular objects to the gel coat;

covering an distal second end of each of the one or more tubular objects;

spraying the fiberglass over the gel coat and the one or more tubular objects.

14. The method of claim 5, wherein the insert has two disk-shaped parts, a first disk-shaped part made from a first material having a higher level of heat conduction such that the structural material adheres to the first disk-shaped part during the heating and a second disk-shaped part made from a second material having a lower level of heat conduction such that the structural material adheres less to the second disk-shaped part during the heating.

15. The method of claim 14, wherein the first material is aluminum and the second material is polytetrafluoroethylene (Teflon).

11. A method of forming an orifice in a wall of a molded product, the molded product being a spa shell, the method comprising:

removably affixing a plurality of inserts on an inside wall of a mold, the mold being in the form of at least a portion of a spa shell;

applying a structural material to the mold, forming the molded product;

allowing the structural material to set;

separating the molded product from the mold, whereas the plurality of inserts separate from the mold by way of the inserts being removably affixed; and

removing the plurality of inserts from the molded product.

12. The method of claim 11, whereas each of the plurality of inserts is removably affixed to the inside wall of the mold by magnetic force.

13. The method of claim 11, wherein the structural material is a resin and the step of applying the structural material to the mold includes heating the mold while rotating the mold.

16. A method of forming a plurality of orifices in a wall of a molded product during rotational molding, the molded product being a spa shell, the method comprising:

affixing a plurality of inserts on an inside surface of a wall of a rotational mold, the rotational mold being in the form of at least a portion of a spa shell, each of the plurality of inserts held to the inside wall of the rotational mold by an apparatus including a magnet and a bracket, the bracket positioning and holding the magnet in place on the wall of the rotational mold, an end of each of the inserts that abuts the inside surface of the wall having a higher thermally conductive disk and a distal end of each of the inserts having a lower thermally conductive disk;

adding a structural material to the rotational mold;

closing the rotational mold;

rotating the rotational mold in two directions while heating the rotational mold, thereby the structural material melts and forms onto the inside surface of the rotational mold and onto the higher thermally conductive disk of each of the inserts;

allowing the structural material to set;

opening the rotational mold;

separating the spa shell from the rotational mold, whereas the plurality of inserts separate from the rotational mold by way of a shearing of the magnetic force holding each insert to the inner wall; and

removing each of the plurality of inserts from the spa shell.

17. The method of claim 16, wherein the structural material is a resin.

18. The method of claim 16, wherein the higher thermally conductive disk is made from metal such that the structural material adheres to the higher thermally conductive disk during the heating and the lower thermally conductive disk is made from plastic such that the structural material adheres less to the lower thermally conductive disk during the heating.

19. The method of claim 18, wherein the metal is aluminum and the plastic is polytetrafluoroethylene (Teflon).

20. The method of claim 16, wherein the higher thermally conductive disk and the lower thermally conductive disk share a common axis, and a diameter of the higher thermally conductive disk is smaller than a diameter of the lower thermally conductive disk.