Method and device for cutting wound hoses

Abstract

A method for cutting a wound hose (1), made from mutually engaging windings (11, 12, 13, 14) of a metallic tape (2), with the wound hose (1) being welded in a predetermined axial area (10) and then cut within the area (10) essentially in a plane (6) extending radially, with the wound hose (1) being axially compressed in the predetermined area prior to welding such that in the area (10) a mutual contacting of the windings (11, 12, 13, 14) occurs. The welding is performed along a predetermined number of windings (11-14) in the area (10), and the welding energy required for welding the windings is introduced via the area of the winding hose into it. Additionally, an accordingly produced wound hose (1) is provided and a device suitable for its production.

Claims

1. A method for cutting a wound hose (1) comprising mutually engaging windings (11, 12, 13, 14) of a metallic tape (2), the method comprising: radially clamping a wound hose (1) on each side of a predetermined axial area (10) by a pair of electrodes, axially compressing together the mutually engaging windings (11, 12, 13, 14) of the wound hose (1) by the pairs of electrodes clamping the wound hose in the predetermined axial area prior to welding, so that in the predetermined axial area (10) a mutually contacting area of windings (11, 12, 13, 14) occurs, welding the wound hose (1) along the mutually contacting area of the windings in the predetermined axial area (10) by the two of the pair of electrodes with the cooperating electrodes of each said pair being embodied to engage about the wound hose, and then cutting the wound hose within said predetermined axial area (10) essentially in a plane (6) extending in a radial direction using a cutting equipment, wherein the welding is performed along a predetermined number of the mutually engaging windings (11, 12, 13, 14), and welding energy required for welding the mutually engaging windings (11-14) is supplied by the predetermined axial area (10) of the wound hose (1) to said predetermined axial area.

2. The method according to claim 1, further comprising performing the welding of the wound hose (1) by capacitor discharge-welding.

3. The method according to claim 2, further comprising each of the two pairs of electrodes being used for the radial clamping of the wound hose and axially applying a compression force to the mutually engaging windings of the wound hose in the predetermined axial area which is located between the two pairs of the electrodes.

4. The method according to claim 3, further comprising using the pairs of electrodes (20, 20; 21, 21) for further compressing of the wound hose (1) after melting of the metallic tape (2) during welding.

5. The method according to claim 3, wherein the electrodes (20, 20; 21, 21) are annular.

6. The method according to claim 1, wherein the predetermined number of windings (11-14) is greater than or equal to 2.

7. The method according to claim 6, wherein the laser beam and/or the wound hose (1) are automatically positioned in reference to one another.

8. The method according to claim 7, wherein the automatic positioning is carried out with an optic device.

9. The method according to claim 1, wherein a width of the predetermined axial area (10) is greater than a width of the welding zone.

10. The method according to claim 1, wherein the cutting device utilizes a laser beam or is a mechanical cutter.

11. The method according to claim 10, wherein the cutting device with the laser beam is provided, and the wound hose (1) is moved in reference to the laser beam.

12. The method according to claim 10, wherein the cutting device with the laser beam is provided, and the laser beam is moved in reference to the wound hose (1).

13. The method according to claim 1, wherein the wound hose is clamped at two edges of the predetermined axial area (10) in order for it to be compressed.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Additional features and advantages of the present invention are discernible from the following description of exemplary embodiments based on the drawing, here showing:

(2) FIG. 1 shows a first cut with the application of the method according to the invention; and

(3) FIG. 2 shows a second cut with the application of the method according to the invention.

(4) FIG. 3 shows a schematic end view of the wound hose with the electrodes being moved toward the position in which they will come into contact with the jacket area.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(5) FIGS. 1 and 2 show the application of the method according to the invention based on an example of a wound hose 1, with its jacket area 3 being formed by a spiral-shaped wound metallic tape 2. In the following, a winding is understood as a single complete revolution of the metallic tape 2 about the (longitudinal) axis 4 of the wound hose 1. FIG. 1 explicitly marks a number of windings 11, 12, 13, 14. Here, the first winding 11 (virtually) begins at the point 7 and ends at the point 8. The second winding 12 begins at the point 8 and ends at the point 9, etc. The metallic tape 2 and/or the windings define a groove 5, which is variable in its width (here also called joint), which also extends spirally and/or over the jacket area 3 and is symbolized in the figures by parallel lines at the edges of the windings. The connection of the metallic tape 2 at its edges is realized by a relatively loose mutual engagement of the neighboring windings. Since the connection is relatively loosely, the joint 5 is variable in its width over the jacket area 2, as already mentioned.

(6) In order to cut the wound hose 1 to a desired length, according to the invention the wound hose 1 is clamped at both sides of the axial point 6 (cf. FIG. 2), at which the cutting shall occur. Then, the axial area 10 is axially compressed between the points, at which the wound hose 1 is clamped, by impinging it with an axially acting force F to block such that in this area 10 a defined mutual contacting occurs of the individual windings 11, 12, 13, 14, resulting in the spirally circumferential joint 5 being constantly minimal in its width and subsequently it can be welded with good quality.

(7) Within the scope of the embodiment of the invention shown, the following process occurs for the welding. According to the illustration in FIG. 1 the device used for the welding process of the wound hose 1 comprises two pairs of electrodes 20, 20 and/or 21, 21, with the cooperating electrodes of each pair each being embodied approximately as half circles, as shown in FIG. 3. The electrodes 20, 20 and/or 21, 21 are made to approach each other in pairs in the radial direction in reference to the wound hose 1 until they come into contact with the jacket area 3. This is symbolized by the arrows P in FIG. 1.

(8) Subsequently the electrodes 20, 20 and/or 21, 21 are axially displaced in pairs in reference to each other, which is symbolized by appropriate arrows P in FIG. 2. When the electrodes 20, 20 and/or 21, 21 contact the wound hose 1 in a force-fitting fashion, this way the wound hose 1 is axially compressed in the above-mentioned area 10, which has already been pointed out.

(9) Subsequently the electrodes 20, 20, 21, 21 are connected via a switch 22, to the capacitor symbolically shown with the reference character C, charged with electric energy, in order to execute the welding process, known per se (capacitor discharge-welding or capacitor pulse welding). Here, the semi-circular electrodes 20, 20 and/or 21, 21 complement each other to form a continuous electrode over the circumference of the wound hose 1 such that in the area 10 between the electrodes 20, 20; 21, 21 the welding of the windings of the wound hose 1 occurs in the area of the spirally circumferential joint 5.

(10) The actual number of windings of the wound hose 1 being welded depends on the axial distance of the electrodes 20, 20; 21, 21. In FIG. 2 the resulting circumferential welding seam is symbolized by a thick, continuous line 5.

(11) Unlike the illustration according to FIG. 1 and FIG. 2, the scope of the invention includes to provide separately designed devices for the axial compression of the wound hose 1 and for the subsequent introduction of the welding energy, i.e. devices for clamping and compressing the wound hose on the one side and separate devices for introducing the welding energy (particularly electrodes) on the other side.

(12) The invention is however not limited in any way to the application of capacitor discharge welding and/or capacitor pulse welding. For example after the compression of a wound hose 1 in the area 10, similar to FIG. 2, here an impingement with ultrasound energy can occur in the above-mentioned area as well, in order to perform friction welding. Preferably, in this context the above-mentioned separate devices are used for compressing the wound hose, on the one hand, and other devices for impinging the wound hose with ultrasound energy in the compressed area 10, which is not explicitly shown in the figures.

(13) It has proven particularly advantageous and sufficient to weld the joint 5 along two windings 11, 12, and to cut the wound hose 1 in the middle 6 of the two windings 11, 12 (in reference to the axial direction). Then a sufficiently long section 10 develops with a precisely defined and even joint 5, and a clean subsequent cutting is possible without any projecting ends. At both ends of the cutting line securely fixed hose ends remain, which are not unraveling.

(14) Due to the compression of the wound hose 1, which has occurred, a relatively large amount of material is available for welding in the joint 5 in the area 10. This particularly relates to mutually interlocking profiles; the folded profile (agraffe profile) cannot be completely pushed together, due to the given geometry. The above-mentioned effect shows advantageous effects, however.

(15) Finally, the wound hose 1 is cut at the predetermined point in a plane extending radially through the center 6 (thus perpendicular in reference to the jacket area 3 and also perpendicular in reference to the axis 4 of the wound hose 1). The cutting occurs advantageously by a laser, alternatively by a mechanical cutting device.

(16) According to FIGS. 1 and 2 the device according to the invention for cutting a wound hose according to the method described here is embodied as follows: A welder is provided for welding the wound hose in a predetermined axial area along a predetermined number of windings. The welder particularly comprise the electrodes 20, 20 and/or 21, 21, the capacitor C, the switch 22, and/or selective connection means for an electric connection of the capacitor C to the electrodes, as well as appropriate electric charging means for the capacitor C, and furthermore actuators for the electrodes 20, 20; 21, 21. These additional means are not explicitly shown in FIGS. 1 and 2.

(17) Further, a cutting device is provided for cutting the wound hose within the predetermined area in a radial plane. This cutting device comprises for example a laser device (not shown). A clamping device is provided for the axial compression of the wound hose in the above-mentioned area, which engage the wound hose and compress it to block such that the individual windings come to contact each other in this area. In the present case, the clamping device coincides with parts of the welding device, i.e. with the electrodes 20, 20 and/or 21, 21. The invention is however not limited to such an embodiment, as already mentioned repeatedly.

REFERENCE CHARACTERS

(18) 1 wound hose

(19) 2 metallic tape

(20) 3 jacket area

(21) 4 axis of the wound hose

(22) 5 groove, joint

(23) 5 welding seam

(24) 6 middle of the area, cutting point, radial plane

(25) 7 point (start/end of winding)

(26) 8 point (start/end of winding)

(27) 9 point (start/end of winding)

(28) 10 axial area of the winding hose

(29) 11 winding

(30) 12 winding

(31) 13 winding

(32) 14 winding

(33) 20 electrode

(34) 20 electrode

(35) 21 electrode

(36) 21 electrode

(37) 22 switch

(38) C capacitor

(39) F force

(40) P direction of motion

(41) P direction of motion