阅读说明：本技术 具有塑料波纹软管的液体管线 (Liquid line with plastic corrugated hose ) 是由 Z·杰尼塞克 P·瓦尼基 于 2021-03-31 设计创作，主要内容包括：本发明涉及一种在有效可生产性方面通过高过程可靠性和高质量可靠性改善了的液体管线(1),所述液体管线包括至少一个波纹软管(2)和至少一个连接件(3),该连接件用于将液体管线(1)连接至另一部件,其中,波纹软管(2)和连接件(3)由塑料制成并且经由至少一个焊接连接部(4)彼此连接,其中,焊接连接部(4)藉由激光焊接方法制成,其中,焊接连接部(4)至少在高达液体管线(1)中的限定的工作压力下是密封的,其中,在连接件(3)中形成有止挡件(5),该止挡件限定波纹软管(2)在连接件(3)中的轴向端部位置。(The invention relates to a liquid line (1) which is improved in terms of effective producibility by means of high process reliability and high quality reliability and which comprises at least one bellows (2) and at least one connection piece (3) for connecting the liquid line (1) to another component, wherein the bellows (2) and the connection piece (3) are made of plastic and are connected to one another via at least one welded connection (4), wherein the welded connection (4) is produced by a laser welding method, wherein the welded connection (4) is sealed at least up to a defined working pressure in the liquid line (1), wherein a stop (5) is formed in the connection piece (3) which defines an axial end position of the bellows (2) in the connection piece (3).)

1. A liquid line (1), in particular for a cleaning appliance in a vehicle, comprising at least one bellows hose (2) and at least one connection piece (3) for connecting the liquid line (1) to another component,

wherein the corrugated hose (2) and the connecting piece (3) are made of plastic and are connected to each other via at least one welded connection (4);

wherein the welded connection (4) is produced by a laser welding method;

wherein the welded connection (4) is sealed at least up to a defined operating pressure in the liquid line (1);

wherein a stop (5) is formed in the connecting piece (3), which stop defines the axial end position of the corrugated hose (2) in the connecting piece (3).

2. The liquid line (1) as claimed in claim 1, characterized in that the connecting piece (3) has a tube section (6) which engages around the end section (7) of the corrugated hose (2) radially on the outside, wherein the welded connection (4) is formed between the tube section (6) and the end section (7) of the corrugated hose (2).

3. Liquid line (1) according to claim 2, characterised in that the bellows (2) has an outer diameter (Da), wherein the end section (7) is calibrated to a defined calibration diameter (Dk) < (Da).

4. The fluid line (1) according to claim 3, characterized in that the calibration is effected thermally.

5. The liquid line (1) as claimed in at least one of claims 3 or 4, characterized in that the calibration diameter (Dk) is selected such that the end section (7) is received into the pipe section (6) by press fit.

6. The liquid line (1) as claimed in at least one of claims 2 to 5, characterized in that the end section (7) comprises at least three corrugations of the corrugated hose (2).

7. The liquid line (1) as claimed in at least one of the preceding claims, characterized in that the stop (5) has a profile which is formed in a substantially completely complementary manner to the corresponding end of the bellows hose (2) over the entire radial extent of the profile.

8. The liquid line (1) according to at least one of the preceding claims, characterized in that the bellows (2) has, in cross section, alternating outer (8) and inner (9) bulges, which end in the region of the extended profile of the inner bulge (9) on the stopper side, in particular at a radially inner low point of the inner bulge (9).

9. The liquid line (1) as claimed in at least one of the preceding claims, characterized in that the connecting piece (3) has a guide element (10) which engages axially into the bellows (2) at the end side.

10. The fluid line (1) as claimed in claim 9, characterized in that the guide element (10) is formed at least on the end side in a tapering or radially inwardly inclined or curved manner on the bellows side.

Technical Field

The invention relates to a liquid line having a corrugated hose made of plastic.

Background

Liquid lines with corrugated hoses made of plastic are known and widely spread. For example, liquid lines of the type mentioned are used for conducting washing liquid in motor vehicle cleaning systems. During production, the corrugated hose is cut to length according to the required dimensions and provided at its end side with corresponding connections/pipe connections in order to quickly connect the liquid line with further components and assemblies, such as nozzles, pumps, containers, etc. Such a connection must be hydraulically sealed to such an extent that the connection permanently withstands the operating pressure in the liquid line, which is usually up to 5 bar.

The wall of the corrugated hose is formed in cross section as outer and inner bulges alternating in sequence. With this construction, the corrugated hose is flexible and pressure resistant and furthermore has a high resistance to buckling. On the other hand, for the same reason, reliable sealing remains challenging when connecting to other components.

DE 10322972 a1, for example, discloses a defined solution for producing a tensile and pressure-tight connection. According to said document, the bellows is sealed in the connection with an O-ring and is fixed by means of a separate fastening ring. However, improvements are considered necessary due to the use of a large number of parts and the consequent high expenses in terms of logistics, assembly and quality control, as well as long production cycles and high material costs.

CN 110594516 a discloses a pipeline consisting of a plastic corrugated hose and a plastic plug connector, in which case the corrugated hose is connected with the plug connector via a welded connection produced by a laser welding process. The plug connector is made of a laser-transparent plastic and has a tubular section for this purpose. The corrugated tube is introduced into the tubular section and welded with the tubular section around the radially outer side with a laser beam.

However, the proposed solution requires specific measures to be taken with respect to the tool in order to bring the bellows and the plug connector into the desired position relative to each other and to hold them securely during welding, which results in a relatively high production outlay and a relatively long production cycle. Especially for small diameter pipelines, process reliability and result continuity need to be improved.

Disclosure of Invention

Against this background, the object of the invention is to provide an improved liquid line which makes it possible in particular to achieve effective producibility with high process reliability and high quality reliability.

This object is achieved by a liquid line having the combination of features as claimed in claim 1. Further developments and further exemplary embodiments of the invention result from the dependent claims as well as from the following description and the drawings.

Drawings

The details and advantages of the present invention will be described in more detail below based on examples. In the drawings:

figure 1 schematically shows a partial view of a fluid line,

figure 2 shows an embodiment of the liquid line in an axial cross-section through the connection,

figure 3 shows the connection piece in plan view and in axial section,

fig. 4 shows an enlarged view of the profile of the stop.

List of reference numerals:

1 liquid line

2 corrugated hose

3 connecting piece

4 welded joint

5 stop piece

6 pipe section

7 end section

8 outer protrusion

9 inner projection

10 guide element

11 receiving space

12 Flange

13 side surface

14 inner inclined plane

15 tapering section

16 connecting pipe

17 laser beam

Da outer diameter

Di inner diameter

Dk calibrated diameter

A central axis

Detailed Description

Fig. 1 shows, by way of example, a part of a liquid line 1 according to the invention, by way of example of a cleaning agent line of a cleaning appliance for a motor vehicle.

The connector 3 is fastened to one side of the corrugated hose 2 in a hydraulically sealed manner and serves for the quick attachment of the liquid line 1 to a unit, assembly or another component.

As will be explained in more detail in connection with the subsequent fig. 2, the connecting piece 3 is laser welded directly to the corrugated hose 2. For this purpose, the connecting element 3 must be made of a plastic material that is transparent to laser light. It is entirely feasible to provide both components from the same base material that is permeable to laser light, wherein a suitable colorant, such as for example carbon black, is mixed into the base material of the corrugated hose 2 in order to reduce or eliminate its penetration.

Fig. 2 shows one end of the fluid line 1 according to fig. 1 in an axial section.

In the exemplary embodiment shown, the connecting element 3 is designed with a connecting piece 16 and is substantially rotationally symmetrical with respect to the center axis a. However, further embodiments (e.g. designed with receiving cavities instead of nipples, extending at an angle instead of straight, etc.) are still equally permissible in the present invention.

On the bellows side, the connection piece 3 has a tube section 6 into which the bellows 2 engages with a separately prepared end section 7.

The pipe section 6 has a defined/prescribed inner diameter Di. The corrugated hose 2 is configured in cross section in the form of an alternating sequence of outer and inner bulges 8, 9, which smoothly transition into each other and have an outer diameter Da > Di.

The end section 7 of the bellows 2 is thus calibrated according to a defined calibration diameter Dk < Da. For a reliable pressure-tight connection, the end section 7 should preferably comprise at least 3 corrugations of the corrugated hose 2. The calibration diameter Dk is selected here such that the end section 7 is received into the pipe section 6 by press fit. Such a calibration can be carried out thermally particularly efficiently and quickly by means suitable for the purpose. Here, the radially outer peaks of the outer projections 8 are plastically deformed and flattened at a defined temperature. In addition to the reduction in diameter, this advantageously also results in an enlarged contact surface between the corrugated hose 2 and the pipe section 6.

Consequently, the subsequent solder connections 4, 4', 4 ″ can be realized more reliably and more widely. The calibration together with the press fit used additionally results in the bellows 2 in the region of the future welded connections 4, 4', 4 ″ reliably bearing against the inner wall of the pipe section 6 over the entire circumference without any air gap. This makes it possible to reduce the precision requirements for the orientation and focusing of the laser beam 17, whereby the welding tool can be designed more simply and cheaply.

In order to position the bellows 2 in a defined axial position with high precision and reproducibly in a positive manner relative to the connecting piece 3 and without additional measuring and orienting outlay for the welding process, a stop 5 is formed in the connecting piece.

In this way, it is then only necessary to insert the bellows 2 into the pipe section 6 until the bellows abuts against the stop 5 and thereby forcibly reaches its desired axial end position. Thereby significantly reducing assembly errors and monitoring costs. Thus, in production, the corrugated hose 2 can be used as a rice item, which is provided with a connector 3 at one end and only then is measured and cut at the other end. The resulting length tolerance can thus be halved compared to a method in which the corrugated hose is first cut to a defined length and only then the connectors are provided at both ends.

In order to further increase the accuracy with which the bellows 2 is positioned, the stop is formed with a profile in cross-section which is formed over its entire extent so as to be substantially complementary to the corresponding end of the bellows 2. In this way, the axial contact surface between the bellows 2 and the connector 3 extends over the entire radial extension of the bellows wall. The adverse effect of angular tolerances and other cutting errors in the cutting off of the corrugated hose 2 on the accuracy of the axial positioning of the corrugated hose in the connecting piece 3 is therefore significantly reduced or even completely eliminated. For further details regarding the stop 5, reference may be made in particular to fig. 4.

In order to eliminate the effect of cutting errors during the severing of the corrugated tube 2 on the welded connection 4 ″ closest to the end and, in addition, to facilitate the introduction of the end portion 7 into the tube portion 6, the corrugated tube 2 should preferably be terminated or cut or severed within the extension distribution region/extension course (Verlauf) of the inner bead 9. It is particularly preferred that the cut-out/profile or end of the bellows should pass through the radially inner low point of the inner protrusion 9, as illustrated in fig. 2.

In order to further simplify the assembly of the corrugated hose 2 in the connection piece 3, to stabilize the position of the end section 7 and to avoid possible buckling or skewing of the corrugated hose in the connection piece, the connection piece is equipped with a guide element 10. In the preferred embodiment shown, the guide element is in the form of a tubular projection which is coaxial with the pipe section 6 and which engages axially into the bellows 2 or the end section 7 on one side. In the radial direction, a receiving space 11 is thus formed between the guide element 10 and the pipe section 6, in which receiving space the end section 7 of the corrugated hose 2 can be reliably received in a protected manner.

After the introduction of the end section 7 into the pipe section 6 until the stop 5 is reached, the welded connection 4, 4', 4 ″ is produced simultaneously or successively by means of a radial or rotary optical laser technique in the region of the contact surface between the calibrated outer projection 8 of the end section 7 and the inner wall of the pipe section 6.

Fig. 3 serves in particular to show the design of a preferred embodiment of the connecting piece 3. In this case, it is particularly important to mention that the pipe section 6 is provided at its bellows-side end with an internal bevel 14 and that the guide element 10 has a narrowing 15 on one side. These construction elements serve as various lead-in ramps during the assembly or insertion of the corrugated hose 2 into the connection piece 3 and, in addition, facilitate this process. Equivalent solutions such as, for example, different types of bends or rounding are also allowed in the present invention.

The connecting element 3 also has a circumferential collar 12. The flange 12 has two diametrically opposed flattened sides 13. The side surfaces improve the handling when assembling the fluid line 1 at its point of use, gripping, handling and connecting the connecting piece 3, and can also be used effectively for marking products.

Fig. 4 shows a preferred embodiment of the stop element 5 in enlarged detail. It can be seen in particular from this figure that, in cross section, the extent of the stop element 5 follows the extent of the outer bead 8 and the inner bead 9 radially from the outside radially inwards, so that the bellows 2 can be supported axially on the stop element 5 over the entire surface, rather than, for example, only at the cut edges.