Screen support rod for screen drawing into a paper machine

Abstract

A screen support rod for screen drawing into a paper machine, the screen support rod including a support tube made from carbon fiber composite material; a telescoping rod; and a bearing that supports the telescoping rod axially movable in an interior of the support tube, wherein the support tube includes a shrink tube that forms a surface that supports the screen during the screen drawing.

Claims

1. A screen support rod for screen drawing into a paper machine, the screen support rod comprising: a support tube made from carbon fiber composite material; a telescoping rod; and a bearing that supports the telescoping rod axially movable in an interior of the support tube, wherein the support tube includes a shrink tube that forms a surface that supports the screen during the screen drawing.

2. The screen support rod according to claim 1, wherein the shrink tube is applied in plural shrink tube sections adjacent to each other.

3. The screen support rod according to claim 1, wherein the support tube is configured as a wound carbon fiber reinforced synthetic material tube.

4. The screen support rod according to claim 1, wherein the telescoping rod is provided as a metal tube made from aluminum or an aluminum alloy.

5. The screen support rod according to claim 1, wherein the telescoping rod is a carbon fiber reinforced synthetic material tube or a wound carbon fiber reinforced synthetic material tube.

6. The screen support rod according to claim 1, wherein the bearing for the telescoping rod includes at least one sliding bushing made from a synthetic material.

7. The screen support rod according to claim 6, wherein the at least one sliding bushing is attached at the telescoping rod by a press fit.

8. The screen support rod according to claim 6, wherein the support tube includes metal head pieces at each end, and wherein the metal head pieces are fixed in the support tube by a press fit.

9. The screen support rod according to claim 8, wherein one of the head pieces supports the telescoping rod during displacement in the support tube.

10. The support tube for the screen support rod according to claim 1, wherein the support tube is configured as a carbon fiber reinforced synthetic material tube, and wherein the shrink tube is applied to the support tube so that the shrink tube forms a surface that supports the screen during the screen drawing.

11. The support tube according to claim 10, wherein the shrink tube is provided in plural shrink tube sections adjacent to each other.

12. The support tube according to claim 10, wherein the support tube is a wound carbon fiber reinforced synthetic material tube.

13. The support tube according to claim 10, further comprising: a respective metal head piece at each end of the support tube, wherein the respective metal head piece (5) is attached in the support tube by a press fit.

14. The screen support rod according to claim 6, wherein the at least one sliding bushing is made from polyoxymethylene.

15. The screen support rod according to claim 6, wherein the at least one sliding bushing includes two sliding bushings.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is subsequently described based on advantageous embodiments with reference to drawing figures. Like components are designated with identical reference numerals in the drawing figures, wherein:

(2) FIG. 1 illustrates a schematic view of a screen rod support including a support tube according to the invention;

(3) FIG. 2 illustrates a schematic view showing an application of the shrink tube;

(4) FIG. 3 illustrates a schematic view showing shrink fit application of the sliding bushings; and

(5) FIG. 4 illustrates a schematic view showing shrink fit application of the head pieces.

DETAILED DESCRIPTION OF THE INVENTION

(6) FIG. 1 shows the screen support rod 10 according to the invention including the support tube 1 according to the invention provided with the shrink tube 2 on an outside. The shrink tube 2 is applied so that it forms the surface that is in contact with the screen during wire drawing. The screen support rod 10 is made from CFC and advantageously provided as a wound CFC tube. Thus, the support tube can be configured particularly light with good bending stiffness. Furthermore, a telescoping rod 3 is provided that is supported axially displaceable in a bearing in the support tube 1. The telescoping rod 3 is advantageously provided as a metal tube, in particular made from aluminum or aluminum alloy.

(7) In order to draw a continuous screen 11 in a paper machine the screen 11 is initially arranged by plural screen support rods 10 adjacent to the paper machine as a screen loop. Thus, the telescoping rod 3 is extended and its free end is attached at a desired position at the frame of the paper machine. The opposite end of the support tube 1 is supported at the frame, at the building or by a building crane. When the continuous screen is arranged in the desired shape of the screen loop the support tube 1 with the screen is moved towards the paper machine so that the telescoping rod 3 is slid into the support tube 1. Thus, the screen is arranged laterally adjacent to the rollers of the paper machines that will support the screen. Subsequently the screen is pulled laterally onto the rollers in the paper machine. Thus, the screen slides over the surface of the screen support rod 10. Since this surface is formed by the smooth shrink tube 2, the sensitive screen is protected against being damaged.

(8) The support tube 1 can be provided with metal head pieces 5 at respective ends of the support tube wherein the head pieces are advantageously attached in the support tube 1 by a press fit. The head pieces 5 protect and reinforce the edge of the support tube 1. Furthermore, the head pieces facilitate receiving the screen support rod 10 in a holder or at a building crane. Additionally, one of the head pieces 5 can be configured so that the telescoping rod 3 is guided and/or supported therein when the telescoping rod 3 is pushed out of the support tube 1.

(9) Additionally, the illustrated embodiment includes two sliding bushings 4 which are advantageously made from POM and configured as rings. The sliding bushings 4 function as supports for the telescoping rod 3 in the support tube 1 and facilitate an axial displacement of the telescoping rod 3. POM is a suitable material since it has a high level of stiffness and dimensional stability combined with a low friction coefficient. The sliding bushings 4 are advantageously pressed into the telescoping rod 3.

(10) The shrink tube 2 is advantageously made from hard PVC which forms a smooth and abrasion resistant surface. The shrinking temperature is typically in a range of 50 to 100 degrees C. In particular the shrink tube 2 can be made from plural annular sections which are applied to the support tube 1 adjacent to each other.

(11) FIG. 2 illustrates how the shrink tube 2 is applied to the support tube 1 to practice the invention. Initially the expanded shrink tube is pulled over the support tube 1 at room temperature RT. Thereafter, the shrink tube 2 is heated, for example, by a hot air blower so that the shrink tube contracts and is fixed at the support tube 1. Thus, the shrink tube forms a surface that comes in contact with the screen during drawing and over which the screen is drawn.

(12) FIG. 3 schematically illustrates how the sliding bushings 4 can be attached at the telescoping rod 3. Initially the sliding bushings 4 are heated above room temperature RT so that they expand slightly and can be slid onto the telescoping rod 3 into the desired position. The sliding bushings 4 contract during cooling so that they are fixed on the telescoping rod 3 by a press fit. This facilitates a safe and reliable support for displacing the telescoping rod 3 in the support tube 1 which requires little installation space and adds little additional weight.

(13) FIG. 4 shows the assembly of the head piece 5 in the support tube 1. The metal head pieces are cooled low enough so that they can be inserted into the support tube 1. When the head pieces heat up to room temperature RT again, they expand and are fixed in the support tube 1 by a press fit. The head pieces 5 reinforce and protect the edges of the support tube 1 against being damaged. Additionally, the head pieces can support the telescoping rod 3 during linear displacement or facilitate attaching or receiving the support tube 1 at a frame, at a building or at a building crane.

REFERENCE NUMERALS AND DESIGNATIONS

(14) 1 support tube 2 shrink tube 3 telescoping rod 4 sliding bushing 5 head piece 10 screen support rod 11 screen RT room temperature