Apparatus and method for stretching and taking-away polymer films

Patent metadata

Field	Value
Publication number	US-10583603-B2
Application number	US-201515538775-A
Country	US
Kind code	B2
Filing date	Dec 16, 2015
Priority date	Dec 22, 2014
Publication date	Mar 10, 2020
Grant date	Mar 10, 2020

Abstract

A film ( 50 ) processing apparatus ( 20 ) including a film stretching device ( 22 ) and a take-away device ( 24 ) and a film processing method using the apparatus. The take-away device receives the film after the stretching device and transports the film along a conveying region in a direction of transport (X). The take-away device includes opposing, first and second conveyor assemblies. The first conveyor assembly has a continuous belt driving a plurality of discrete pads ( 180 a, 180 b ). Each pad forms a contact face ( 194 a, 194 b ) extending between leading ( 200 b ) and trailing edges ( 202 a ). The pads are configured and arranged such that the trailing edge ( 202 a ) of a first pad ( 180 a ) overlaps the leading edge ( 200 b ) of an immediately adjacent second pad ( 180 b ) as the first and second pads traverse the conveying region. The overlap is characterized by a line ( 322 ) perpendicular to the direction of transport passing at any given moment through the first and second pads. A shape of the contact face can define a major central axis that is non-perpendicular and non-parallel with the direction of transport.

First claim

What is claimed is:

1. An apparatus for processing a film, the apparatus comprising:
a stretching device for stretching a received film; and
a take-away device that receives the film after the stretching device, the take-away device establishing an entrance side, an exit side, and a conveying region interfacing with and transporting the film in a direction of transport from the entrance side to the exit side;
wherein the take-away device includes a first track including opposing, first and second conveyor assemblies arranged to contact opposing surfaces of the film, respectively, along the conveying region, the first conveyor assembly including:
a continuous belt driven along a path of travel,
a plurality of discrete pads carried by the belt, each of the pads forming a contact face opposite the belt for contacting the film along the conveying region, the contact face extending between opposing, leading and trailing edges, the leading edge arranged downstream of the trailing edge relative to the path of travel,
wherein the plurality of pads includes a first a pad immediately adjacent a second pad;

and further wherein the first and second pads are configured and arranged such that the trailing edge of the first pad overlaps the leading edge of the second pad as the first and second pads are traversed along the conveying region.

2. The apparatus of claim 1 , wherein the path of travel further includes a wrap region leading to the conveying region, and further wherein the first and second pads are configured and arranged such that the trailing edge of the first pad does not overlap the leading edge of the second pad as the first and second pads are traversed along at least a portion of the wrap region.

3. The apparatus of claim 1 , wherein the trailing edge of the first pad overlaps the leading edge of the second pad as the first and second pads are traversed along at least the majority of the conveying region.

4. The apparatus of claim 1 , wherein a major central axis defined by a shape of the contact face of each of the first and second pads is non-perpendicular and non-parallel to the direction of transport.

5. The apparatus of claim 1 , wherein a plane defined by a majority of the leading edge of the first and second pads is non-perpendicular and non-parallel to the direction of transport.

6. The apparatus of claim 1 , wherein the first and second pads are configured and arranged such that at an instantaneous location of the first and second pads along the conveying region, a line perpendicular to the direction of transport passes through the first and second pads.

7. The apparatus of claim 1 , wherein the contact face of each of the first and second pads further defines opposing, first and second side edges, the leading and trailing edges extending between the corresponding first and second side edges.

8. The apparatus of claim 7 , wherein with respect to the second pad:
a first corner is defined between the leading edge and the first side edge; and
a second corner is defined between the leading edge and the second side edge;
wherein an angle of the first corner differs from the angle of the second corner.

9. The apparatus of claim 8 , wherein the angle of the first corner is greater than 90°.

10. The apparatus of claim 9 , wherein the angle of the second corner is 90°.

11. The apparatus of claim 7 , wherein with respect to the second pad the leading edge defines a first segment in extension from the first side edge and a second segment in extension from the second side edge, and further wherein an intersection of the first and second segments defines an angle of less than 180°.

12. The apparatus of claim 11 , wherein a length of the first segment is greater than a length of the second segment.

13. The apparatus of claim 11 , wherein with respect to the second pad:
a first corner is defined at an intersection of the leading edge and the first side edge;
a second corner is defined at an intersection of the trailing edge and the first side edge;
wherein an angle of the first corner differs from the angle of the second corner.

14. The apparatus of claim 13 , wherein with respect to the second pad:
a third corner is defined at an intersection of the leading edge and the second side edge; and
a fourth corner is defined at an intersection of the trailing edge and the second side edge;
wherein an angle of the third corner approximates the angle of the first corner, and the angle of the fourth corner approximates the angle of the second corner.

15. The apparatus of claim 1 , wherein the first and second pads each form the corresponding leading edge as a curve corner.

16. The apparatus of claim 1 , wherein the continuous belt is a chain comprising a plurality of interconnected links, and further wherein respective ones of the plurality of pads are attached to individual ones of the plurality of links.

17. The apparatus of claim 16 , wherein a line of attachment between the first pad and the corresponding link is off-set between the corresponding leading and trailing edges.

18. The apparatus of claim 1 , wherein the plurality of pads further includes a third pad, and further wherein a shape of the third pad differs from a shape of the first and second pads.

19. The apparatus of claim 1 , wherein each of the plurality of pads has an identical shape.

20. The apparatus of claim 1 , wherein the first conveyor assembly is located below the second conveyor assembly.

21. The apparatus of claim 20 , wherein the second conveyor assembly includes:
a continuous belt;
a plurality of discrete pads carried by the belt and each forming a contact face for contacting the film along the conveying region;
wherein the contact face of at least one of the pads of the second conveyor assembly defines a shape identical to the contact face of the first pad.

22. The apparatus of claim 20 , wherein the second conveyor assembly includes:
a continuous belt;
a plurality of discrete pads carried by the belt and each forming a contact face for contacting the film along the conveying region;
wherein the contact face of each of the pads of the second conveyor assembly has a shape differing from a shape of the first pad.

23. The apparatus of claim 1 , wherein the take-away device further includes a second track including opposing, first and second conveyor assemblies arranged to contact the opposing surfaces of the film, respectively, along the conveying region, the second track being spaced from the first track, and further wherein the first conveyor assembly of the second track includes:
a continuous belt driven along a path of travel;
a plurality of discrete pads carried by the belt and including first and second pads identical to the first and second pads of the first track.

24. The apparatus of claim 1 , wherein the stretching device is configured to convey the film in a machine direction, and further wherein the direction of transport of the take-away device is in-line with the machine direction.

25. A method of processing a film, the method comprising:
conveying a film within a stretching device;
stretching the film within the stretching device; and
transporting the film in a direction of transport downstream of the stretching device with a take-away device, the take-away device including a first track with opposing, first and second conveyor assemblies, the first conveyor assembly including a plurality of discrete pa

Assignees

• 3M Innovative Properties Co

Inventors

• Jackson Jeffery N

Classifications

• B29C55/08 Primary

  transverse to the direction of feed · CPC title

• B29C55/20 Primary

  Edge clamps · CPC title

• B65G17/326

  Clamps, constituted by articulated chain links · CPC title

• B29C2793/009

  after shaping · CPC title

• B29K2995/0051

  mono-axially · CPC title