FLUID LINE HAVING A WAVE FORM PORTION

Abstract

A fluid line having a wave form portion is furnished. The wave form portion extends at least at a minimum distance along a longitudinal axis of the fluid line. The wave form portion has a wave peak element (18), which itself has, along a peripheral direction extending around the longitudinal axis of the fluid line, a varying distance from the longitudinal axis, the distance including a distance curve in the peripheral direction, the distance curve providing a non-circular contour. A fluid line is thus provided having a wave form portion, which fluid line reduces the pressure drop at the wave form portion.

Claims

1. A fluid line having a wave form portion, wherein the wave form portion extends at least at a minimum distance along a longitudinal axis of the fluid line, wherein the wave form portion has a wave crest element which has a varying distance to the longitudinal axis along a circumferential direction extending around the longitudinal axis of the fluid line, wherein the distance comprises a distance profile in the circumferential direction, wherein the distance profile provides a non-circular contour.

2. The fluid line as claimed in claim 1, wherein the distance in the circumferential direction changes according to a sine function.

3. The fluid line as claimed in claim 1, wherein the wave crest element extends in the circumferential direction only around a partial circumference of the wave form portion.

4. The fluid line as claimed in claim 1, wherein the wave crest element has a maximum distance to the longitudinal axis, wherein a position of the maximum distance in the circumferential direction is arranged diametrically opposite a position of the wave form portion which has the minimum distance to the longitudinal axis.

5. The fluid line as claimed in claim 1, wherein the fluid line has a wave-free wall portion which has a smooth surface along the longitudinal axis, wherein the wave form portion in the circumferential direction comprises a first end region and a second end region, wherein the wave-free wall portion extends between the first and the second end region.

6. The fluid line as claimed in claim 5, wherein the wave-free wall portion is arranged at the minimum distance to the longitudinal axis.

7. The fluid line as claimed in claim 5, wherein the distance of the wave-free wall portion to the longitudinal axis in the circumferential direction is constant.

8. The fluid line as claimed in claim 5, wherein the wave-free wall portion has a neutral axis of the fluid line.

9. The fluid line as claimed in claim 6, wherein the wave-free wall portion in the circumferential direction covers an angle in the range between 0° and 180°.

10. The fluid line as claimed in claim 1, wherein the fluid line has at least one wave-free line portion which extends along the longitudinal axis away from the wave form portion.

11. The fluid line as claimed in claim 1, wherein the wave form portion has a plurality of wave crest elements, wherein in each case a wave trough element is arranged between in each case two wave crest elements, which wave trough element is arranged at the minimum distance to the longitudinal axis.

12. The fluid line as claimed in claim 11, wherein the fluid line has a curve in which the wave form portion is arranged.

13. The fluid line as claimed in claim 12, wherein the wave crest element is arranged on an outer radius of the curve.

14. The fluid line as claimed in claim 12, wherein the wave form portion has the minimum distance on an inner radius of the curve across its entire extent along the longitudinal axis.

15. The fluid line as claimed in claim 1, wherein the distance in the circumferential direction changes according to a square of a sine function.

16. The fluid line as claimed in claim 6, wherein the wave-free wall portion in the circumferential direction covers an angle in the range between 0° and 120°.

17. The fluid line as claimed in claim 6, wherein the wave-free wall portion in the circumferential direction covers an angle in the range between 0° and 80°.

Description

[0030] Further features, details and advantages of the invention arise from the wording of the claims and from the following description of exemplary embodiments on the basis of the drawings. In the drawings:

[0031] FIGS. 1a, b show sectional drawings of a schematic representation of a fluid line having a wave form portion;

[0032] FIG. 2 shows a schematic representation of a fluid line having a bent wave form portion; and

[0033] FIG. 3 shows a diagram with exemplary profiles of the varying distance along the circumferential direction.

[0034] A fluid line is represented schematically in FIG. 1a and is referred to in its entirety by the reference number 10.

[0035] FIG. 1a shows schematic representation of fluid line 10 in a side view. Fluid line 10 extends in the horizontal direction along longitudinal axis 16 and can be formed from an extruded plastic material. Fluid line 10 further comprises a wave form portion 12 which extends at a minimum distance 14 to longitudinal axis 16 along longitudinal axis 16 of fluid line 10. Wave form portion 12 is arranged between two line portions 28 which do not have a wave form. On the contrary, line portions 28 have a smooth wall. In this case, wave form portion 12 is arranged at a position at which a curve should be produced in fluid line 10.

[0036] Wave form portion 12 has at least partially a wave-shaped wall portion which has at least one wave crest element 18 which extends between a maximum distance 24 to longitudinal axis 16 and minimum distance 14 to longitudinal axis 16. Wave form portion 12 comprises according to figure la a plurality of wave crest elements 18 which are separated from one another by wave trough elements 34. A wave trough element 34 is arranged at minimum distance 14 to longitudinal axis 16. The number of wave crest elements 18 in wave form portion 12 can be adapted to the length of extent or the bending angle of the provided curve. The larger the bending angle of the provided curve, the more wave crest elements 18 can be used.

[0037] The at least one wave crest element 18 extends according to FIG. 1b in a circumferential direction 20, extending around longitudinal axis 16, of fluid line 10. FIG. 1b shows a view of fluid line 10 along longitudinal axis 16. The representation of fluid line 10 corresponds in this case to a section along line A-A from FIG. 1a, wherein longitudinal axis 16 is arranged orthogonally to the sectional surface.

[0038] Along circumferential direction 20, wave crest element 18 has a varying distance 22 to longitudinal axis 16. I.e. if wave crest element 18 is followed along circumferential direction 20, distance 22 of wave crest element 18 to longitudinal axis 16 changes. Various angle positions of the wave crest element 18 along circumferential direction 20, which can also be referred to here as circumferential positions, have different distances 22 to longitudinal axis 16.

[0039] This brings about that wave crest element 18 is formed to have varying flexibility at the various circumferential positions. The local flexibility of wave crest element 18 can thus be adjusted so that it corresponds to the required local flexibility for generating a curve in fluid line 10. Regions which are supposed to form an outer radius of the curve have increased flexibility, in which distance 22 are increased in these regions up to maximum distance 24. The remaining regions in which an inner radius of the curve should be formed have smaller or no increased distances 22 at their circumferential positions.

[0040] In this case, wave crest element 18 comprises a first circumferential position at which wave crest element 18 has maximum distance 24 to longitudinal axis 16. The first circumferential position is diametrically opposite a further circumferential position at which wave crest element 18 has minimum distance 14 to longitudinal axis 16.

[0041] Wave crest element 18 furthermore extends in circumferential direction 20 only around a partial circumference of wave form portion 12. In this case, wave crest element 18 comprises a first end region 30 and a second end region 32. At both end regions 30, 32 of wave crest element 18, varying distance 22 is reduced from maximum distance 24 proceeding in circumferential direction 20 until it corresponds to minimum distance 14 at a circumferential position outside wave crest element 18. Varying distance 22 consequently increases between the two end regions 30, 32 continuously up to maximum distance 24. A circumferential position with a maximum flexibility and a circumferential position with a minimum flexibility lie diametrically opposite one another in circumferential direction 20. When a curve 36 is created in fluid line 10, the flexibility of the circumferential position with maximum distance 24 to longitudinal axis 16 is therefore primarily deformed and the circumferential position with minimum distance 14 to longitudinal axis 16 is deformed to a small degree or not at all.

[0042] The two end regions 30, 32 are connected to one another in circumferential direction 20 outside wave crest element 18 in wave form portion 12 by a wave-free wall portion 26, which can also be referred to as a smooth region. Wave-free wall portion 26 has in this case a smooth wall which has no waves in a direction along longitudinal axis 16 and in circumferential direction 20, rather is formed to be smooth. Moreover, wave-free wall portion 26 is arranged at minimum distance 14 from longitudinal axis 16. The distance of wave-free wall portion 26 to longitudinal axis 16 can furthermore be constant over its entire surface.

[0043] This brings about that, in order to produce a curve in fluid line 10 after a bending process of the wave form portion 12, free wall portion 26 provides a non-corrugated edge surface for the fluid flow arranged in fluid line 10 on an inner radius of the curve. A fluid flow will thus only have a low degree of friction and turbulence on the inner radius of the curve. This avoids an interruption in the fluid flow from wave-free wall portion 26 so that vortices and thus a drop in pressure in fluid line 10 are reduced or avoided.

[0044] FIG. 2 shows fluid line 10, in the case of which wave form portion 12 is bent and provides a curve 36 in fluid line 10. Curve 36 has in this case an outer radius 38 and an inner radius 40. Wave crest elements 18 with wave trough elements 34 therebetween extend in circumferential direction 20 over the region of curve 36 which is arranged on outer radius 38. The plurality of wave crest elements 18 in interaction with wave trough elements 34 are arranged along outer radius 38 and form along longitudinal axis 16 the wave form of wave form portion 12. The region around inner radius 40 of curve 36 is free from wave crest elements 18.

[0045] Greater flexibility of the material of fluid line 10 by means of wave crest elements 18 is thus provided on outer radius 38 of curve 36 than on inner radius 40 of curve 36. This brings about that the material on outer radius 38 of curve 36 can be stretched along longitudinal axis 16 without a large degree of effort. By varying distance 22 in circumferential direction 20, the flexibility of the material which is provided by wave crest elements 18 is reduced up to end regions 30, 32 of wave crest elements 18.

[0046] As a result of this, the local stretching of wave form portion 12 is likewise reduced at these positions. I.e., along circumferential direction 20, the material of fluid line 10 is subject to a varying degree of stretching depending on distance 22 of wave crest element 18. No stretching of the material is performed any more at inner radius 40 of curve 36. Neutral axis 42 of fluid line 10 is arranged at this position.

[0047] Wave-free wall portion 26 is neither compressed nor stretched at neutral axis 42. A slight stretching of wave-free wall portion 26 which is facilitated with the start of end regions 30, 32 as a result of the increase in the flexibility of wave form portion 12 is performed in the direction of wave crest elements 18.

[0048] As a result of this, vortices in a fluid flow which flows through fluid line 10 and through curve 36 are avoided. As a result of the avoidance of vortices in the fluid flow, a drop in pressure in the fluid flow is furthermore reduced or even avoided.

[0049] FIG. 3 shows a diagram 44 that plots the difference of the local distance of a circumferential position of a wave crest element 18 to minimum distance 14 against the circumferential angle in circumferential direction 20. The difference is standardized to the maximum difference, i.e. the difference between maximum distance 24 and minimum distance 14. The circumferential angle is represented here from 0° to 180°, wherein it is assumed that, in the case of a circumferential angle of 180°, the circumferential position of wave crest element 18 is arranged with maximum distance 24. The distance profile in circumferential direction 20 provides a non-circular contour. Starting from the 0° position, diagram 44 shows the distance profile in circumferential direction 20 and in the opposite direction to circumferential direction 20. I.e. that diagram 44 only shows half a rotation around the longitudinal axis in circumferential direction 20 or counter to circumferential direction 20.

[0050] A first distance profile 46 of wave crest element 18 in circumferential direction 20 is sinusoidal in this case, wherein the minimum distance is present between an angle range between 0° and 40° and the sinusoidal profile begins from the angle position 40°. I.e. wave-free wall portion 26 or smooth region covers, in circumferential direction 20, an angle between 0° and 180°, preferably between 0° and 120°, further preferably between 0° and 80°. The maximum of first distance profile 46 is arranged in the case of angle position 180°.

[0051] A second distance profile 48 has a form which corresponds to the square of a sine. Second distance profile 48 initially rises to a lesser extent than first distance profile 46. In the case of larger circumferential angles, the gradient of second distance profile 48 is, however, larger than the gradient of first distance profile 46 so that second distance profile 48 at the 180° position also has maximum distance 24.

[0052] The two distance profiles 46,48 merely show examples of varying distance 22 along circumferential direction 20 of a wave crest element 18. Other profiles of the distance are consequently not ruled out and can likewise be applied. In particular, in circumferential direction 20, the angle range of wave-free wall portion 26 or of wave crest element 18 can be formed to be larger or smaller than explained in this exemplary embodiment.

[0053] The invention is not restricted to one of the embodiments described above, but rather can be modified in various ways.

[0054] All of the features and advantages which proceed from the claims, the description and the drawing, including constructive details, spatial arrangements and method steps, can be essential to the invention both on their own and in the wide range of combinations.

LIST OF REFERENCE NUMBERS

[0055] 10 Fluid line

[0056] 12 Wave form portion

[0057] 14 Minimum distance

[0058] 16 Longitudinal axis

[0059] 18 Wave crest element

[0060] 20 Circumferential direction

[0061] 22 Varying distance

[0062] 24 Maximum distance

[0063] 26 Wall portion

[0064] 28 Line portion

[0065] 30 First end region

[0066] 32 Second end region

[0067] 34 Wave trough element

[0068] 36 Curve

[0069] 38 Outer radius

[0070] 40 Inner radius

[0071] 42 Neutral axis

[0072] 44 Distance/angle diagram

[0073] 46 First distance profile

[0074] 48 Second distance profile