Method for forming a laminated part

Patent metadata

Field	Value
Publication number	US-10086555-B2
Application number	US-201213465253-A
Country	US
Kind code	B2
Filing date	May 7, 2012
Priority date	Oct 27, 2011
Publication date	Oct 2, 2018
Grant date	Oct 2, 2018

Abstract

A method for thermoforming a laminate to a part by controlling the temperature and pressure during the thermoforming. The laminate to be thermoformed may include an adhesive layer and the part may be a metal article. A thermoforming box may be used to control one of the temperature and the pressure.

First claim

What is claimed is:

1. A method of applying a laminate having an adhesive layer to a contoured surface of a metal article, the method comprising: heating the laminate to a thermoformable temperature;
after heating the laminate, applying a differential pressure across the laminate to pre-stretch the laminate and define a pre-stretched laminate;
heating the metal article to a temperature above a bonding temperature of the adhesive, but below the thermoformable temperature;
positioning the heated laminate above the heated article; after the pre-stretched laminate is defined, moving the metal article to initiate physical contact with the pre-stretched laminate; and
after the physical contact, rapidly applying, within three seconds, the pre-stretched laminate onto the contoured surface by applying a differential pressure across the pre-stretched laminate to conform the pre-stretched laminate to the contoured surface without ripples in the pre-stretched laminate,
wherein the rapidly applying the pre-stretched laminate further comprises applying the pre-stretched laminate before any portion of the adhesive falls below the bonding temperature.

2. The method of claim 1 wherein the applying the differential pressure across the pre-stretched laminate to conform the pre-stretched laminate to the contoured surface without ripples in the pre-stretched laminate comprises evacuating fluid from below the pre-stretched laminate and pressurizing fluid above the pre-stretched laminate.

3. The method of claim 1 wherein the rapidly applying the pre-stretched laminate comprises instantaneously applying the pre-stretched laminate.

4. The method of claim 1 wherein the heating the laminate comprises heating both sides of the laminate.

5. The method of claim 1 wherein the heating the laminate comprises heating the laminate until the laminate reaches a predetermined draw ratio.

6. The method of claim 5 wherein the predetermined draw ratio is greater than 1:1.

7. The method of claim 1 wherein the applying the differential pressure comprises applying a low pressure, less than atmospheric pressure, on a first side of the pre-stretched laminate, which is a same side of the pre-stretched laminate as the metal article.

8. The method of claim 7 wherein the applying the differential pressure across the pre-stretched laminate to conform the pre-stretched laminate to the contoured surface without ripples in the pre-stretched laminate further comprises applying a high pressure, greater than the low pressure, on a second side of the pre-stretched laminate opposite the first side.

9. The method of claim 8 wherein the applying the high pressure comprises applying a pressure of at least 1 atmosphere.

10. The method of claim 9 wherein the applying the high pressure comprises fluidly coupling the second side to the atmosphere and then fluidly sealing the second side to the atmosphere and pressurizing the second side to greater than one atmosphere of pressure.

11. The method of claim 1 wherein the metal article includes openings and the rapidly applying the pre-stretched laminate onto the contoured surface includes removing air between the pre-stretched laminate and the metal article through the openings.

12. A method of applying a laminate having an adhesive layer to an article within a thermoforming box and fluidly separated by the laminate into a first portion, on one side of the laminate, and a second portion, on an opposite side of the laminate, and having a buck supporting the article in the one side, the method comprising:
heating the laminate to a first temperature corresponding to a thermoforming temperature for the laminate;
prior to bringing the laminate into contact with the article, applying a differential pressure across the laminate to pre-stretch the laminate and define a pre-stretched laminate;
heating the article to a second temperature that is above an instantaneous bonding temperature for the adhesive but below the thermoforming temperature;
after the pre-stretched laminate is defined, moving the heated article to initiate physical contact with the pre-stretched laminate; and
applying a second pressure differential across the pre-stretched and heated laminate while the laminate is at the first temperature and the article is at the second temperature to draw the pre-stretched laminate across the article, within three seconds of the physical contact and without forming ripples in the pre-stretched laminate,
wherein the pre-stretched laminate is applied to the article before any portion of the adhesive falls below the instantaneous bonding temperature.

13. The method of claim 12 wherein the heating the article comprises heating the buck to a temperature above the instantaneous bonding temperature for the adhesive but below the thermoforming temperature.

14. The method of claim 13 wherein the heating the article further comprises pre-heating the article exteriorly of the thermoforming box.

15. The method of claim 14 wherein the heating the article further comprises maintaining the article at the second temperature.

16. The method of claim 15 wherein the heating the laminate further comprises pre-heating the laminate exteriorly of the thermoforming box.

17. The method of claim 15 wherein the heating the laminate comprises heating both sides of the laminate.

18. The method of claim 12 wherein the heating the laminate comprises heating the laminate until the laminate reaches a predetermined draw ratio.

19. The method of claim 18 wherein the predetermined draw ratio is greater than 1:1.

20. The method of claim 12 wherein the applying the second differential pressure across the pre-stretched and heated laminate to draw the pre-stretched laminate across the article without forming ripples in the pre-stretched laminate comprises applying a low pressure, less than atmospheric pressure, to the first portion.

21. The method of claim 20 wherein the applying the low pressure comprises evacuating air from the first portion of the box through the buck.

22. The method of claim 21 wherein the applying the second differential pressure across the pre-stretched and heated laminate to draw the pre-stretched laminate across the article without forming ripples in the pre-stretched laminate further comprises applying a high pressure, greater than the low pressure, to the second portion of the box.

23. The method of claim 22 wherein the applying the high pressure comprises applying a pressure of at least 1 atmosphere.

24. The method of claim 23 wherein the applying the high pressure comprises fluidly coupling the second portion to the atmosphere and then fluidly sealing the second portion to the atmosphere and pressurizing the second portion to greater than one atmosphere of pressure.

25. The method of claim 12 , further comprising cooling the article after applying the second differential pressure.

26. The method of claim 12 wherein the article includes openings and the drawing the laminate across the article without forming ripples in the laminate includes removing air between the laminate and the article through the openings.

27. The method of claim 1 wherein the applying the differential pressure across the pre-stretched and heated laminate to conform the pre-stretched laminate to the contoured surface without ripples in the pre-stretched laminate occurs after the heated article contacts a lowest point

Assignees

• Kessler Patrick J
• Rittenhouse Heather L
• Alongi James
• Alongi Paul
• Whirlpool Co

Inventors

• Kessler Patrick J
• Rittenhouse Heather L
• Alongi James
• Alongi Paul

Classifications

• B29C2791/006

  Using vacuum · CPC title

• B29C51/08

  Deep drawing or matched-mould forming, i.e. using mechanical means only · CPC title

• B29K2705/00

  Use of metals, their alloys or their compounds, for preformed parts, e.g. for inserts · CPC title

• B29C51/46

  Measuring, controlling or regulating · CPC title

• B29C51/421

  of preforms, specially adapted for thermoforming (preheating sheets in general B29B13/023; B29C51/427 takes precedence) · CPC title