Method of making a seat cushion

• US 6,120,630 A
• Filed: 04/07/1998
• Issued: 09/19/2000
• Est. Priority Date: 11/13/1995
• Status: Expired due to Fees

• Current Assignee: Milsco Manufacturing Company (Jason Industries, Inc.)
• Original Assignee: Milsco Manufacturing Company (Jason Industries, Inc.)
• Inventors: Lorbiecki, James R.
• Primary Examiner(s): YAO, SAMCHUAN CUA
• Application Number:
  US09/056,319
• Time in Patent Office: 896 Days
• Field of Search: 29/91.1, 29/91.5, 29/91.7, 156/285, 156/229, 156/494, 156/224, 156/222, 156/214, 156/212, 156/79, 156/196, 156/245
• US Class Current: 156/79
• CPC Class Codes: B29C 2791/001 Shaping in several steps
• CPC Class Codes: B29C 2791/006 Using vacuum
• CPC Class Codes: B29C 44/14 the preformed part being a lining B29C44/1209 takes precedence
• CPC Class Codes: B29C 44/146 Shaping the lining before foaming
• CPC Class Codes: B29C 51/10 Forming by pressure difference, e.g. vacuum
• CPC Class Codes: B29C 51/145 having at least one layer of textile or fibrous material combined with at least one plastics layer
• CPC Class Codes: B29K 2105/04 cellular or porous
• CPC Class Codes: Y10T 156/1002 with permanent bending or reshaping or surface deformation of self sustaining lamina
• CPC Class Codes: Y10T 156/1028 by bending, drawing or stretch forming sheet to assume shape of configured lamina while in contact therewith
• CPC Class Codes: Y10T 156/1031 with preshaping of lamina
• CPC Class Codes: Y10T 156/1044 of parallel stacked sheets only
• CPC Class Codes: Y10T 156/1048 to form dished or receptacle-like product

Abstract

A method of forming fabric for making foam-in-place molded articles such as preferably seat cushions. A film is secured to a frame and tacked by adhesive to a piece of fabric, not secured to the frame, that forms the outer covering of the seat cushion for permitting the fabric to move relative to the film during forming to enable fabrics which cannot stretch a considerable amount to be used. To form the fabric, the film and fabric are placed in a female mold and the film and fabric are drawn into a cavity of the mold and against a contoured surface in the cavity forming a recess in the film and fabric. To counteract compressive stresses in the fabric during forming, the frame can have one or more fabric tensioners that selectively apply tension to the fabric during forming. To mold the cushion, a foam is poured into the recess and allowed to cure until it hardens into a foam core and bonds with the film. Preferably, to fix the shape of the film and fabric to that of the contoured surface of the mold cavity to enable the foam to be poured into the recess without requiring the film and fabric to be supported by the mold, the adhesive, film and fabric are heated before forming to make them pliable and cooled after forming to fix their shape to substantially conform to that of the contoured surface of the mold cavity.

Claims

1. A method of making a seat cushion comprising:

(a) providing a film constructed of a stretchable material, a frame in which the film is secured, a seat cover fabric, an adhesive, a mold having a cavity with a contoured seat cushion-forming surface, and a foamable material for making a support core for supporting the shape of the seat cover fabric after its shape has been fixed,

(b) securing the film to the frame,

(c) placing the seat cover fabric on the film with the adhesive between the seat cover fabric and film and without securing the seat cover fabric to the frame,

(d) orienting the seat cover fabric, adhesive, and film on a surface such that the fabric is disposed closest to the surface and the film is disposed over the fabric,

(e) tacking the seat cover fabric to the film using a vacuum that urges the film toward the surface and against the fabric,

(f) forming the seat cover fabric and film by drawing the seat cover fabric and film into the cavity of the mold such that the seat cover fabric is three-dimensionally contoured,

(g) fixing the shape of the seat cover fabric so that it substantially conforms to the seat cushion-forming contoured surface of the mold cavity, and

(h) supporting the shape of the seat cover fabric by disposing the support core, that comprises the foamable material formed in situ, in the recess in the seat cover fabric to form a seat cushion.

2. The method of making a seat cushion of claim 1 wherein the support core is comprised of foam.

3. The method of making a seat cushion of claim 1 wherein before or during step (e) the step further comprising heating the adhesive.

4. The method of making a seat cushion of claim 3 wherein the fluid is heated until it becomes a fluid and during step (e) the fabric and film are drawn together while the adhesive is fluid.

5. The method of making a seat cushion of claim 4 wherein the surface comprises a vacuum table in communication with a vacuum source.

6. The method of making a seat cushion of claim 3 wherein during heating of the adhesive the adhesive is heated to a temperature that renders the adhesive a fluid permitting the seat cover fabric to move relative to the film.

7. The method of making a seat cushion of claim 6 wherein the adhesive has an activation temperature above which it becomes a fluid and during heating of the adhesive the adhesive is heated to a temperature above its activation temperature to permit the seat cover fabric to move relative to the film during step (f).

8. The method of making a seat cushion of claim 7 wherein during heating of the adhesive the adhesive is heated to a temperature of at least about two hundred degrees Fahrenheit.

9. The method of making a seat cushion of claim 8 wherein during step (f) the fabric and film are drawn together.

10. The method of making a seat cushion of claim 9 wherein the surface comprises a vacuum table in communication with a vacuum source.

11. The method of making a seat cushion of claim 10 wherein the mold is a vacuum mold in communication with a vacuum source and during step (f) the seat cover fabric and film are placed in the mold with the seat cover fabric disposed closest to the mold cavity and the film overlying the seat cover fabric and thereafter applying a vacuum to draw the seat cover fabric into the cavity of the mold.

12. The method of making a seat cushion of claim 11 wherein the fabric moves relative to the film during step (f).

13. The method of making a seat cushion of claim 12 wherein the seat cover fabric is a fabric capable of stretching no greater than one hundred percent.

14. The method of making a seat cushion of claim 13 wherein the seat cover fabric is a low stretch fabric that is capable of stretching no greater than fifty percent.

15. The method of making a seat cushion of claim 12 comprising during step (f) the further step of applying tension to a portion of the seat cover fabric in a direction generally opposing the seat cover fabric being drawn into the cavity of the mold.

16. The method of making a seat cushion of claim 12 further comprising providing a hook carried by the frame biased to apply a tension to a portion of the seat cover fabric and during step (f) engaging the hook to a portion of the seat cover fabric and opposing movement of the seat cover fabric into the cavity of the mold.

17. The method of making a seat cushion of claim 16 comprising providing a generally U-shaped spring operably connected to the hook and the frame that biases the hook so that it can move relative to the frame to apply a tension to a portion of the seat cover fabric.

18. The method of making a seat cushion of claim 12 wherein during step (g) the adhesive bonds the seat cover fabric to the film.

19. The method of making a seat cushion of claim 18 wherein the temperature of the adhesive is lowered to cause the adhesive to bond the seat cover fabric to the film during step (g).

20. The method of making a seat cushion of claim 19 wherein the temperature of the adhesive is lowered to a temperature that is below its activation temperature.

21. The method of making a seat cushion of claim 18 wherein the support core is comprised of a thermally activated liquid foam and during step (h) thermally activated liquid foam is poured into a recess formed in the seat cover fabric and allowed to harden during or after step (g).

22. The method of making a seat cushion of claim 21 wherein after step (g) the seat cover fabric and film are removed from the mold before step (h).

23. The method of making a seat cushion of claim 5 wherein the seat cover fabric is disposed against the vacuum table and the vacuum table has a roughened surface that grips the seat cover fabric when the vacuum is applied in step (e) to resist shrinkage of the seat cover fabric when the adhesive is heated.

24. The method of making a seat cushion of claim 5 wherein the vacuum table is separate from the mold and the seat cover fabric, adhesive and film are transferred from the vacuum table to the mold before step (f).

25. The method of making a seat cushion of claim 5 wherein a portion of the film extends outwardly beyond the periphery of the seat cover fabric so that the portion of the film seals directly against the vacuum table during step (e).

26. The method of making a seat cushion of claim 25 wherein the adhesive is heated to a temperature of at least 280°

Fahrenheit while a vacuum of at least about 5 inches of mercury is applied by the vacuum table to urge the film toward the vacuum table and against the fabric.

27. The method of making a seat cushion of claim 1 wherein the surface and the mold are separate components, and the seat cover fabric, adhesive and film are transferred from the surface to the mold after step (e) and before step (f).

28. The method of making a seat cushion of claim 1 wherein the seat cover fabric is comprised of at least two pieces of fabric that are each capable of stretching no more than 50%.

29. The method of making a seat cushion of claim 28 wherein each piece of fabric of the seat cover fabric is not joined at or about its periphery to any other piece of fabric.

30. The method of making a seat cushion of claim 1 wherein the seat cover fabric comprises a low stretch fabric that is capable of stretching no more than 50% and the film comprises a polymeric film that is capable of stretching at least 150%.

31. The method of making a seat cushion of claim 30 wherein the film is heated to or above a temperature at which the shape memory of the film is reset.

32. The method of making a seat cushion of claim 31 wherein the film and the adhesive are heated at the same time and before step (g).

33. The method of making a seat cushion of claim 32 wherein the film comprises a urethane film and the adhesive comprises a heat activated polyamide adhesive and during heating the film and the adhesive are heated to a temperature of at least 200°

Fahrenheit.

34. The method of making a seat cushion of claim 30 wherein the film is heated to a temperature of at least 100°

Fahrenheit before forming takes place in step (f).

35. The method of making a seat cushion of claim 34 wherein the film is heated to a temperature of between about 230°

Fahrenheit and about 250°

Fahrenheit.

36. The method of making a seat cushion of claim 1 wherein the adhesive is in a fluid state during step (f) permitting the seat cover fabric to move relative to the film during forming.

37. A method of making a seat cushion comprising:

(a) providing a film comprised of a polymeric or plastic material that is capable of being stretched at least 150%, a frame in which the film is attached, a seat cover fabric comprised of a fabric that is capable of stretching no more than 100%, an adhesive, a mold having a cavity with a contoured seat cushion-forming surface, and a foamable liquid for forming a compressible foam support core for supporting the shape of the seat cover fabric,

(b) attaching the film to the frame,

(c) placing the seat cover fabric on the film with the adhesive between the seat cover fabric and film and without securing the seat cover fabric to the frame,

(d) positioning the seat cover fabric, adhesive, and film on a surface such that the fabric is disposed closest to the surface and the film is disposed over the fabric,

(e) heating the seat cover fabric, adhesive, and film to a temperature of at least 200°

Fahrenheit such that the adhesive becomes a fluid,

(f) tacking the seat cover fabric to the film by applying a vacuum that urges the film against the fabric,

(g) forming the seat cover fabric and film by applying a vacuum that draws the seat cover fabric and film into the cavity of the mold such that the seat cover fabric is three-dimensionally contoured,

(h) fixing the shape of the seat cover fabric such that its shape substantially conforms to the three-dimensionally contoured shape of the mold cavity by cooling or allowing to cool the seat cover fabric, adhesive and film so that

     1) the shape memory of the film is set such that its shape substantially conforms to the shape of the mold cavity, and the

     2) adhesive bonds the fabric to the film, and

(i) supporting the shape of the seat cover fabric by disposing the compressible foam support core in a recess in the seat cover fabric and film to form a seat cushion, wherein the compressible foam support core is comprised of the foamable material that is formed in situ.

38. The method of making a seat cushion of claim 37 wherein the compressible foam support core is comprised of a foamable liquid that is poured into the recess in the seat cover fabric and film during step (i) and thereafter allowing the foamable liquid to foam and harden.

39. The method of making a seat cushion of claim 38 wherein during step (g) tension is selectively applied to the seat cover fabric that opposes drawing the fabric into the mold cavity.

40. The method of making a seat cushion of claim 39 wherein the seat cover fabric is comprised of a low stretch fabric that is capable of stretching no more than 50%.

41. A method of making a seat cushion comprising:

(a) providing a film comprised of a polymeric or plastic material that is capable of being stretched at least 150%, a frame in which the film is secured, a seat cover fabric comprised of a low stretch fabric that is capable of stretching no more than 50%, an adhesive, a mold having a cavity with a contoured seat cushion-forming surface, and a liquid foaming material,

(b) attaching the film to the frame,

(c) placing the seat cover fabric on the film with the adhesive between the seat cover fabric and film and without securing the seat cover fabric to the frame,

(d) positioning the seat cover fabric, adhesive, and film on a surface such that the fabric is disposed closest to the surface and the film is disposed over the fabric,

(e) heating the seat cover fabric, adhesive, and film to a temperature of at least 200°

Fahrenheit such that the adhesive becomes a fluid,

(f) applying a vacuum to urge the film toward the surface and against the fabric while the adhesive is a fluid to cause the fabric to adhere to the film,

(g) forming the seat cover fabric and film by applying a vacuum to draw the seat cover fabric and film into the cavity of the mold while the adhesive is a fluid such that the seat cover fabric is three-dimensionally contoured and the film is stretched more than the seat cover fabric,

(h) fixing the shape of the seat cover fabric such that its shape substantially conforms to the three-dimensionally contoured shape of the mold cavity by cooling or allowing to cool the seat cover fabric, adhesive and film so that

     1) the shape memory of the film is set such that its shape substantially conforms to the shape of the mold cavity, and the

     2) adhesive sets and bonds the fabric to the film, and

(i) supporting the shape of the seat cover fabric by pouring the liquid foaming material into a recess in the seat cover fabric and film and allowing the liquid foaming material to foam and harden.

42. The method of making a seat cushion of claim 41 wherein the adhesive sets by hardening into a solid.