Device and method for cooling a blown film

Patent metadata

Field	Value
Publication number	US-10974434-B2
Application number	US-201615580542-A
Country	US
Kind code	B2
Filing date	Jun 8, 2016
Priority date	Jun 8, 2015
Publication date	Apr 13, 2021
Grant date	Apr 13, 2021

Abstract

The invention relates to a calibration device (1) for calibrating a blown film (6), said device comprising; —a tubular region (55) with at least one inner wall (92), through which region the blown film (6) can be passed; —a liquid reservoir which provides a liquid and which is situated above the tubular region (55); an inlet region, in which the liquid can be introduced into the space between the outer wall of the blown film (6) and the inner wall (92) of the tubular region (55); and —a scraper device (117), situated below the tubular region (55), by means of which scraper device at least part of the liquid can be removed from the outer surface. The distance of the liquid-removing regions of the scraper device (117) from the main axis of the blown film (6) can be altered.

First claim

The invention claimed is:

1. A device for cooling a blown film, with a device for applying liquid onto the outer wall of the blown film, wherein the film can be cooled with the liquid, wherein the liquid can be introduced between a tubular region and the blown film, wherein the blown film can be transported in a transport direction (z), with a single removal element for removing at least a part of the liquid from the blown film, wherein the removal element comprises an annular, flat strip consisting of an elastic material, and discrete points that surround at least parts of the blown film in the circumferential direction, wherein the removal element, viewed in the transport direction (z) is situated behind the tubular region, and upon encountering an alteration of the diameter of the blown film, the distance which the removal element has from the main axis of the blown film can be altered accordingly by a force introduction device that attacks the discrete points with outwardly directed radial forces such that liquid continues to be removed, wherein the removal element maintains a circumferential, uninterrupted circular edge facing the outer surface of the blown film via the elasticity of the elastic material.

2. The device according to claim 1 , wherein the device for applying liquid comprises at least one film guide element with at least one inner wall which is arranged at least partially around the blown film and along which the blown film can be passed.

3. The device according to claim 1 , wherein a liquid reservoir is provided above or in the upper region of the film guide element and with which the liquid can be provided, wherein the liquid can be guided between the film guide element and the blown film.

4. The device according to claim 1 , wherein the removal element is situated underneath the at least one film guide element.

5. The device according to claim 1 , wherein a suction removal device is situated, viewed in the direction of transport of the blown film, between the at least one film guide element and the removal element and with which the liquid can be removed at least partially from the outer wall of the blown film.

6. The device according to claim 1 , wherein the removal device comprises an annular, flat strip consisting of a rubber material.

7. The device according to claim 1 , wherein the device comprises a drive which provides an adjustment force for altering the distance.

8. The device according to claim 1 , wherein the force introduction device comprises a plurality of adjustment elements comprising wires or bands which can be moved radially outward and which can be loaded with traction.

9. The device according to claim 8 , wherein the adjustment elements are flexible and substantially constant in their length.

10. The device according to claim 1 , wherein a mechanism for transmitting drive power is provided with a drive power which can be converted into an adjustment force for adjusting the removal element.

11. The device according to claim 10 , wherein the mechanism for transmitting drive power transmits the drive power directly or via winding rollers onto the adjustment elements.

12. The device according to claim 10 , wherein the mechanism for transmitting drive power comprises at least one endlessly rotating power transmission element.

13. The device according to claim 12 , wherein the endlessly rotating power transmission element comprises a chain.

14. The device according to claim 12 , wherein the endlessly rotating power transmission element comprises a ring.

15. A method for cooling a blown film, in which a liquid is applied onto the outer wall of the blown film by a device for applying liquid, wherein the film is cooled with the liquid, wherein the liquid is introduced between a tubular region and the blown film, wherein the blown film is transported in a transport direction (z), with a single removal element for removing at least a part of the liquid from the blown film, wherein the removal element comprises an annular, flat strip consisting of an elastic material, and discrete points that surround at least parts of the blown film in the circumferential direction, wherein the removal element, viewed in the transport direction (z), is situated behind the tubular region, and wherein upon encountering an alteration of the diameter of the blown film, the distance which the removal element has from the main axis of the blown film is altered accordingly by a force introduction device that attacks the discrete points with outwardly directed radial forces such that liquid continues to be removed, wherein the removal element maintains a circumferential, uninterrupted circular edge facing the outer surface of the blown film via the elasticity of the elastic material.

Assignees

• Windmoeller & Hoelscher

Inventors

• Goldenstein Jens
• Steuter Henning

Classifications

• B29C48/912

  of tubular films · CPC title

• B29C48/885

  External treatment, e.g. by using air rings for cooling tubular films · CPC title

• B29C48/908

  characterised by calibrator surface, e.g. structure or holes for lubrication, cooling or venting · CPC title

• B29C48/907 Primary

  using adjustable calibrators, e.g. the dimensions of the calibrator being changeable · CPC title

• B29C2948/92619

  Diameter or circumference · CPC title