Circumferentially variable surface temperature roller

• US 20070060457A1
• Filed: 09/15/2005
• Published: 03/15/2007
• Est. Priority Date: 09/15/2005
• Status: Abandoned Application

• Current Assignee: SKC Haas Display Films Co., Ltd. (Dow, Inc.)
• Original Assignee: Eastman Kodak Company
• Inventors: Garcia, Jose, Bomba, Richard
• Application Number:
  US11/227,827
• Publication Number:
  US 20070060457A1
• Time in Patent Office: Days
• US Class Current: 492/46
• CPC Class Codes: B29C 2043/023 having a plurality of grooves
• CPC Class Codes: B29C 2043/522 selectively heating a part of the mould to achieve partial heating, differential heating
• CPC Class Codes: B29C 33/026 in rolls, calenders or drums
• CPC Class Codes: B29C 33/04 using liquids, gas or steam tyre moulds with incorporated heating or cooling means using liquids, gas or steam B29D30/0601
• CPC Class Codes: B29C 33/044 in rolls calenders or drums
• CPC Class Codes: B29C 33/08 for dielectric heating
• CPC Class Codes: B29C 43/46 Rollers
• CPC Class Codes: B29C 43/52 Heating or cooling
• CPC Class Codes: F28F 5/02 Rotary drums or rollers

Abstract

A casting roller having a variable temperature surfaces comprises a rotatable cylindrical shell (12). Axially aligned heating electric elements (14) are equally spaced and internal to an outer surface of the rotatable cylindrical shell. A brush assembly (16) is in electrical contact with the heating elements during a portion of the rotatable cylindrical shell rotation about an axis. A stationary core (26) is internal to the rotatable cylindrical shell. An annular space is between the stationary core and the rotatable cylindrical shell. A cooling fluid fills (22) at least a portion of the annular space.

Claims

1. A casting roller having a variable temperature surface comprising:

a rotatable cylindrical shell;

axially aligned heating electric elements equally spaced and internal to an outer surface of said rotatable cylindrical shell;

a brush assembly in electrical contact with said heating elements during a portion of said rotatable cylindrical shell rotation about an axis;

a stationary core internal to said rotatable cylindrical shell;

an annular space between said stationary core and said rotatable cylindrical shell; and

a cooling fluid filling at least a portion of said annular space.

2. A casting roller as in claim 1 wherein a baffle confines said cooling fluid to a portion of said annular space.

3. A casting roller as in claim 1 wherein said cooling fluid is selected from a group comprising organic synthetic media that has an operating temperature range of 60 C to 350 C (140 F-662 F).

4. A casting roller as in claim 3 wherein the viscosity of the fluid varies from 8.2 centipoise to 0.26 centipoise.

5. A casting roller as in claim 3 wherein specific heat of said media varies from 1.62 kJ/kg*K at 60 C to 2.82 kJ/kg*K at 360 C.

6. A casting roller as in claim 3 wherein thermal conductivity varies from 0.125 W/m*K at 60 C to 0.086 W/m*K at 360 C.

7. A casting roller as in claim 3 wherein density of said media varies from 1016 kg/m3 at 60 C to 801 kg/m3 at 360 C.

8. A casting roller as in claim 1 wherein said heating elements are cartridge heaters.

9. A casting roller as in claim 8 wherein said heaters are 0.25 inch diameter with a heat flux output of approximately 60 W/in2.

10. A casting roller having a variable surface temperature comprising:

a rotatable cylindrical shell;

a stationary core internal to said rotatable cylindrical shell;

an annular space between said stationary core and said rotatable cylindrical shell;

baffles creating a first and second region in said annular space;

a first fluid at a first temperature circulating in said first annular space; and

a second fluid at a second temperature circulating in said second annular space.

11. A casting roller as in claim 10 wherein said first fluid is a cooling fluid and is selected from a group comprising organic synthetic fluid has an operating temperature range of 60 C to 350 C (140 F-662 F).

12. A casting roller as in claim 11 wherein a viscosity of the fluid varies from 8.2 centipoise to 0.26 centipoise.

13. A casting roller as in claim 11 wherein a specific heat of said fluid varies from 1.62 kJ/kg*K at 60 C to 2.82 kJ/kg*K at 360 C.

14. A casting roller as in claim 11 wherein thermal conductivity of said fluid varies from 0.125 W/m*K at 60 C to 0.086 W/m*K at 360 C.

15. A casting roller as in claim 11 wherein a density of said fluid varies from 1016 kg/m3 at 60 C to of 801 kg/m3 at 360 C.

16. A casting roller as in claim 10 wherein said first annular space covers one third of the circumference of the shell at a time.

17. A casting roller as in claim 10 wherein said second annular space covers two thirds of said cylindrical shell at a time.

18. A casting roller as in claim 10 wherein:

said rotatable cylindrical shell is thin; and

a shoe supports said rotatable cylindrical shell at a nip.

19. A method of casting a web of material comprising:

contacting said web within a heating zone of said roller;

raising said web to a casting temperature;

forming an impression on said web;

maintaining said web in contact with said roller through at least a portion of a cooling zone on said roller; and

stripping said web from said roller after said web has cooled.

20. A method as in claim 19 wherein said roller surface temperature is increased 30 degrees centigrade to 60 degrees centigrade greater than a web glass transition temperature.

21. A method as in claim 19 wherein said roller surface temperature is decreased to 3 degrees centigrade to 5 degrees centigrade less than a web glass transition temperature.

22. A casting roller having a variable surface temperature comprising:

a rotatable cylindrical shell;

a stationary core internal to said rotatable cylindrical shell;

an annular space between said stationary core and said rotatable cylindrical shell;

baffles creating a first and second region in said annular space;

a first fluid at a first temperature circulating in said first annular space;

a second fluid at a second temperature circulating in said second annular space;

wherein said rotatable cylindrical shell is thin; and

a shoe which supports said rotatable cylindrical shell at a nip.

23. A casting roller as in claim 22 wherein:

a third region is created by said buffer surrounding said shoe; and

a third fluid at a third temperature is in said third region.

24. A casting roller as in claim 23 wherein said third fluid lubricates said shoe.