Method and apparatus for forming an apertured pad

• US 20010016548A1
• Filed: 01/30/2001
• Published: 08/23/2001
• Est. Priority Date: 03/19/1999
• Status: Active Grant

• Current Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Original Assignee: Joseph Michael Kugler, Michael Barth Venturino
• Inventors: Kugler, Joseph Michael, Venturino, Michael Barth
• Granted Patent: US 6,454,690 B2
• Time in Patent Office: Days
• US Class Current: 493/370
• CPC Class Codes: A61F 13/15626 Making fibrous pads without outer layers
• CPC Class Codes: A61F 13/15658 Forming continuous, e.g. composite, fibrous webs, e.g. involving the application of pulverulent material on parts thereof
• CPC Class Codes: A61F 13/15707 Mechanical treatment, e.g. notching, twisting, compressing, shaping
• CPC Class Codes: A61F 13/15764 Transferring, feeding or handling devices; Drives
• CPC Class Codes: A61F 13/533 having discontinuous areas of compression

Abstract

An apparatus and method for manufacturing a pad wherein a rotatable forming screen which has a generally cylindrical surface and at least one outwardly projecting nob is employed. The nob is positioned on the forming screen whereby the nob is circumscribed by the material, e.g., cellulosic fluff, deposited on the forming screen to form the pad. The pad is transferred from the forming screen to a moveable transfer surface. The transfer surface may be either flat or round and moves at a velocity which is at least as great as the velocity of the forming screen. The nob located on the forming screen includes a thrust surface disposed on a trailing edge of the nob. The thrust surface imparts a compressive force on the pad during the release of the pad from the forming screen. The compressive force is at least partially directed towards the transfer surface and thereby assists in the release and transfer of the pad. A vacuum may also be used to attract the pad to the transfer surface. When the transfer surface is a cylindrical surface, the forming screen may have a diameter which is smaller than, substantially equivalent to, or greater than the diameter of the transfer surface. The nobs disposed on the forming screen can have many different shapes and, for example, may define a frustum. The sidewalls of the nob may taper inwardly by about 5 degrees. Threaded fasteners may be utilized to make the nobs reattachable and exchangeable.

Claims

1. A method of manufacturing a pad, said method including:

providing a forming screen with at least one outwardly projecting nob;

rotating said forming screen whereby said forming screen has a first tangential velocity;

forming the pad on said forming screen wherein the pad completely encircles said at least one nob, the pad having a first surface disposed in contact with said forming screen and a second surface disposed opposite the first surface;

providing a moving transfer surface adjacent the second surface of the pad, said transfer surface moving in a direction substantially corresponding to the movement of the adjacent second surface, said transfer surface moving at a second velocity which is at least as great as said first velocity;

engaging said transfer surface with the adjacent second surface; and

transferring the pad to said transfer surface wherein a trailing edge of said nob exerts a compressive force on the pad, said compressive force including a component vector directed towards said transfer surface.

2. The method of

claim 1

wherein the second surface of the pad is intersected by said nob.

3. The method of

claim 1

wherein said transfer surface is a flat surface.

4. The method of

claim 3

wherein said second velocity is greater than said first velocity.

5. The method of

claim 3

wherein said second velocity is at least about 102 percent of said first velocity.

6. The method of

claim 3

wherein said second velocity is at least about 103 percent of said first velocity.

7. The method of

claim 1

wherein said transfer surface is a cylindrical surface.

8. The method of

claim 1

wherein said forming screen includes a plurality of outwardly projecting nobs.

9. The method of

claim 1

wherein said at least one nob is reattachably secured to said forming screen.

10. The method of

claim 9

wherein said at least one nob is threadingly attachable.

11. The method of

claim 1

wherein said at least one nob has a distal end and side walls extending from said forming screen to said distal end, said nob having a first cross sectional area at said forming screen and a second cross sectional area at said distal end, at least a portion of said side walls having an inward inclination of at least about 5 degrees.

12. The method of

claim 11

wherein said at least one nob is a frustum.

13. The method of

claim 1

wherein said transferring step further includes using a vacuum to attract the pad to the transfer surface.

14. A method of manufacturing a pad, said method including:

providing a forming screen, said forming screen defining a first cylindrical surface with a first radius and having at least one outwardly projecting nob;

rotating said forming screen whereby said forming screen has a first tangential velocity;

forming the pad on said forming screen whereby the pad completely encircles said at least one nob, the pad having a first surface disposed in contact with said forming screen and a second surface disposed opposite the first surface;

providing a rotatable transfer surface adjacent the second surface of the pad, said transfer surface defining a second cylindrical surface with a second radius;

engaging said transfer surface with the second surface of the pad at a second tangential velocity which is at least as great as said first velocity, said forming screen and said transfer surface having opposite rotational directions; and

transferring the pad to said transfer surface wherein a trailing edge of said nob exerts a compressive force on the pad, said compressive force including a component vector directed towards said transfer surface.

15. The method of

claim 14

wherein the second surface of the pad is intersected by said nob.

16. The method of

claim 14

wherein said second velocity is greater than said first velocity.

17. The method of

claim 14

wherein said second velocity is at least about 101 percent of said first velocity.

18. The method of

claim 14

wherein said second velocity is at least about 102 percent of said first velocity.

19. The method of

claim 14

wherein said second velocity is at least about 103 percent of said first velocity.

20. The method of

claim 14

wherein said at least one nob has a distal end and side walls extending from said forming screen to said distal end, said nob having a first cross sectional area at said forming screen and a second cross sectional area at said distal end, said first cross sectional area being greater than said second cross sectional area, at least a portion of said side walls having an inward inclination of least about 5 degrees.

21. The method of

claim 20

wherein said at least one nob is a frustum.

22. The method of

claim 14

wherein said forming screen has a plurality of outwardly projecting nobs.

23. The method of

claim 14

wherein said at least one nob is reattachably secured to said forming screen.

24. The method of

claim 23

wherein said at least one nob is threadingly attachable.

25. The method of

claim 14

wherein said first radius is substantially equivalent to said second radius.

26. The method of

claim 14

wherein said first radius is larger than said second radius.

27. The method of

claim 14

wherein said transferring step further includes using a vacuum to attract the pad to the transfer surface.

28. An apparatus for manufacturing a pad, said apparatus comprising:

a rotatable forming screen, said forming screen having a generally cylindrical surface and at least one outwardly projecting nob, said at least one outwardly projecting nob interiorly positioned on said forming screen whereby said forming screen circumscribes said nob, said forming screen being rotatable at a rate defining a first tangential velocity;

a material source positioned adjacent said forming screen whereby a material layer is depositable on said forming screen and said at least one nob is circumscribable by the material layer, the material layer thereby forming the pad and having a first surface disposed in contact with said forming screen and a second surface disposed opposite said first layer;

a moveable transfer surface, said transfer surface being engageable with the second surface of the material layer, said transfer surface being moveable in a direction substantially corresponding to the movement of the engageable material layer and at a second velocity, said second velocity being at least as great as said first velocity;

a means for attracting the material layer to said transfer surface; and

a thrust surface disposed on a trailing edge of said at least one nob, said thrust surface imparting a compressive force on the engageable material layer as said forming screen and said transfer surface respectively move at said first and second velocities, said compressive force including a component vector directed towards said transfer surface.

29. The apparatus of

claim 28

wherein said transfer surface is a substantially flat surface.

30. The apparatus of

claim 29

wherein said second velocity is greater than said first velocity.

31. The apparatus of

claim 29

wherein said second velocity is at least about 102 percent of said first velocity.

32. The apparatus of

claim 29

wherein said second velocity is at least about 103 percent of said first velocity.

33. The apparatus of

claim 28

wherein said transfer surface is a substantially cylindrical surface.

34. The apparatus of

claim 28

wherein said forming screen includes a plurality of outwardly projecting nobs interiorly positioned on said forming screen whereby said forming screen circumscribes each of said plurality of nobs.

35. The apparatus of

claim 28

wherein said at least one nob is reattachable on said forming screen.

36. The apparatus of

claim 35

further comprising a threaded fastener securing said at least one nob.

37. The apparatus of

claim 28

wherein said at least one nob has a distal end and side walls extending from said forming screen to said distal end, said nob having a first cross sectional area at said forming screen and second cross sectional area at said distal end, at a portion of said side walls having an inward inclination of at least about 5 degrees.

38. The apparatus of

claim 37

wherein said at least one nob is a frustum.

39. The apparatus of

claim 28

further comprising a scarfing device, said scarfing device positioned to remove excess material disposed outwardly of a distal end of said at least one nob.

40. The apparatus of

claim 28

wherein said means for attracting the material layer comprises a vacuum source disposed in operative communication with said transfer surface.

41. An apparatus for manufacturing a pad, said apparatus comprising:

a rotatable forming screen, said forming screen defining a first generally cylindrical surface with a first radius and having at least one outwardly projecting nob, said at least one outwardly projecting nob interiorly positioned on said forming screen whereby said forming screen circumscribes said nob, said forming screen being rotatable at a rate defining a first tangential velocity;

a material source positioned adjacent said forming screen whereby a material layer is air layable on said forming screen and said at least one nob is circumscribable by the material layer, the material layer thereby forming a pad and having a first surface disposed in contact with said forming screen and a second surface disposed opposite said first layer;

a rotatable transfer surface, said transfer surface defining a second generally cylindrical surface with a second radius, said transfer surface being engageable with the second surface of the material layer, said transfer surface and said forming screen having opposed rotatable directions, said transfer surface being movable at a second tangential velocity, said second velocity being greater than said first velocity;

a vacuum source disposed in operative communication with said transfer surface whereby said material layer is attractable to said transfer surface; and

a thrust surface disposed on a trailing edge of said at least one nob, said thrust surface imparting a compressive force on the engageable material layer as said forming screen and said transfer surface respectively move at said first and second velocities, said compressive force including a component vector directed towards said transfer surface.

42. The apparatus of

claim 41

wherein said first radius is substantially equivalent to said second radius.

43. The apparatus of

claim 41

wherein said first radius is larger than said second radius.

44. The apparatus of

claim 41

wherein said second velocity is greater than said first velocity.

45. The apparatus of

claim 41

wherein said second velocity is at least about 101 percent of said first velocity.

46. The apparatus of

claim 41

wherein said second velocity is at least about 102 percent of said first velocity.

47. The apparatus of

claim 41

wherein said second velocity is at least about 103 percent of said first velocity.

48. The apparatus of

claim 41

wherein said forming screen includes a plurality of outwardly projecting nobs interiorly positioned on said forming screen whereby said forming screen circumscribes each of said plurality of nobs.

49. The apparatus of

claim 41

wherein said at least one nob is reattachable on said forming screen.

50. The apparatus of

claim 49

further comprising a threaded fastener securing said at least one nob.

51. The apparatus of

claim 41

wherein said at least one nob has a distal end and side walls extending from said forming screen to said distal end, said nob having a first cross sectional area at said forming screen and second cross sectional area at said distal end, a portion of said side walls having an inward inclination of at least about 5 degrees.

52. The apparatus of

claim 51

wherein said at least one nob is a frustum.

53. The apparatus of

claim 41

further comprising a scarfing device, said scarfing device positioned to remove excess material disposed outwardly of a distal end of said at least one nob.