Air conduction element for reducing air resistance of a load-carrying vehicle

Abstract

An air conduction element for reducing the air resistance of a load-carrying vehicle having a load space structure. The air conduction element can be externally mounted in the rear region of the load space structure and includes an air conduction duct with a front air inlet opening and a rear air outlet opening, front and rear being in relation to the direction of travel (x). The air inlet opening overlaps the load space structure in the direction of travel (x) and the air outlet opening is arranged behind the load space structure within the cross-sectional contour thereof. The air conduction element has a cover which delimits the air conduction duct. It was therefore the aim to devise an air conduction element which does not increase the dimensions of the load space structure when the vehicle is driving slowly or is at a standstill. For this purpose, the cover is produced from a flexible flat material.

Claims

1. An air conduction element for reducing air resistance of a load-carrying vehicle having a cargo space structure, which can be externally mounted in a rear region of the cargo space structure and comprises an air conduction duct with a front air inlet opening and a rear air outlet opening in a direction of travel (x), wherein the air inlet opening overlaps the cargo space structure in the direction of travel (x) and the air outlet opening is arranged behind the cargo space structure within its cross section contour, wherein the air conduction element comprises a cover which delimits the air conduction duct, wherein the cover is produced from a flexible flat structure, and wherein elastic clasps are arranged in the air inlet opening, running from the cover to the cargo space structure.

2. The air conduction element as claimed in claim 1, wherein the cover is held by spacing elements on the cargo space structure.

3. The air conduction element as claimed in claim 2, wherein the spacing elements engage with the cover and the cargo space structure.

4. The air conduction element as claimed in claim 2, wherein the spacing elements are formed from belts or cables.

5. The air conduction element as claimed in claim 2, wherein the spacing elements are ribs extending in the direction of travel (x).

6. The air conduction element as claimed in claim 5, wherein the ribs are made from the flexible flat structure.

7. The air conduction element as claimed in claim 1, wherein an apron is secured on the cover extending as far as the air outlet opening.

8. The air conduction element as claimed in claim 7, wherein the apron is made from the flexible flat structure.

9. The air conduction element as claimed in claim 1, wherein the cover is formed with an airfoil.

10. The air conduction element as claimed in claim 9, wherein the airfoil is formed by the flexible flat structure.

11. The air conduction element as claimed in claim 10, wherein a pocket is formed in the flexible flat structure open in the direction of travel (x) and/or in the direction of the cargo space structure, which may be filled by the air flow.

12. The air conduction element as claimed in claim 11, wherein the pocket is formed by an upper sail and a lower sail.

13. The air conduction element as claimed in claim 12, wherein the pocket comprises a fill opening which is arranged between the upper sail and lower sail.

14. The air conduction element as claimed in claim 13, wherein the fill opening is held open by struts.

15. The air conduction element as claimed in claim 1, wherein the air conduction duct has a conically tapering section starting at the air inlet opening in the direction of the air outlet opening.

16. The air conduction element as claimed in claim 1, wherein the air conduction duct has a variable cross section in dependence on the position of the cover.

17. The air conduction element as claimed in claim 3, wherein the spacing elements are ribs extending in the direction of travel (x), wherein the ribs are made from the flexible flat structure, and wherein an apron is secured on the cover extending as far as the air outlet opening.

18. The air conduction element as claimed in claim 17, wherein the apron is made from the flexible flat structure, wherein the cover is formed with an airfoil, and wherein the airfoil is formed by the flexible flat structure.

19. The air conduction element as claimed in claim 18, wherein a pocket is formed in the flexible flat structure open in the direction of travel (x) and/or in the direction of the cargo space structure, which may be filled by the air flow, wherein the pocket is formed by an upper sail and a lower sail, wherein the pocket comprises a fill opening which is arranged between the upper sail and lower sail, wherein the fill opening is held open by means of struts; and wherein the air conduction duct has a conically tapering section starting at the air inlet opening in the direction of the air outlet opening.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) For better understanding, the invention shall be explained more closely below with the aid of four figures. There are shown:

(2) FIG. 1: a side view of a load-carrying vehicle with several air conduction elements arranged in the rear region of a load-carrying vehicle;

(3) FIG. 2: an enlarged side view of the air conduction element according to FIG. 1;

(4) FIG. 3: a front view of an air conduction element according to FIG. 2 and

(5) FIG. 4: a top view of an air conduction element according to FIGS. 1 to 3.

DETAILED DESCRIPTION OF THE INVENTION

(6) FIG. 1 shows a side view of a load-carrying vehicle 1 consisting of a tractor unit 1a and a semitrailer 1b releasably attached to it by means of a fifth wheel coupling 23. The semitrailer 1b comprises a cargo space structure 2, in which goods can be transported protected against external factors.

(7) The cargo space structure 2 is formed by a roof wall 2a, two opposite side walls 2b extending in the direction of travel x, a front wall 2d bounding off the cargo space structure 2 from the tractor unit 1a in the direction of travel x and a rear wall 2c. In particular, the rear wall 2c can be provided with swiveling doors (not shown) for loading and unloading.

(8) In the rear region 3 of the cargo space structure 2 are located one air conduction element 4 each on the roof wall 2a and on the side walls 2b. Each of the three air conduction elements 4 has an air conduction duct 5 oriented in the direction of travel x with an air inlet opening 6 located in the direction of travel x and an air outlet opening 7 situated at the opposite end. The air outlet opening 7 should be formed with a larger cross section as compared to the air conduction duct 5 and also the air inlet opening 6. This accomplishes a diffuser effect with a decreased speed of the air flowing through the air conduction element 4 while at the same time increasing its pressure. The air outlet opening 7 furthermore lies inside the cross section contour of the cargo space structure 2 and thus in a region in which a negative pressure is formed during driving operation. The orientation of the air outlet opening 7 lies basically in the same plane as the direction of travel x.

(9) The air conduction elements 4 in the representation of FIG. 1 are in a raised position with respect to the cargo space structure 2, that is, during fast driving of the load-carrying vehicle 1.

(10) In the representations of FIG. 2 and FIG. 3, the air conduction element 4 is shown in detail with a cover 8 formed as an airfoil 16, wherein the cover 8 is made from a flexible flat structure 9 and the airfoil 16 is blown open after going beyond the required air speed. The cover 8 preferably has an upper sail 21 and a lower sail 22, which are joined together at the end opposite the direction of travel x and thereby form a pocket 18. At the end of the pocket 18 situated in the direction of travel x the upper sail 21 is folded down by as much as 180 and thereby forms an onflow edge 24, which in turn is connected to the lower sail 22. For the greater portion of the width of the cover 8 a fill opening 19 is situated between the onflow edge 24 and the lower sail 22, through which air flows into the pocket 18 and stiffens the cover 8 in the side regions by a back pressure effect.

(11) In order to ensure a lifting of the cover 8 especially when wet and when the flexible flat structure 9 is clinging to the cargo space structure 2, the fill openings 19 may be held open by struts 20. These should be made of a flexible material, such as plastic or wire, and should engage with the upper sail 21 and the lower sail 22 on both sides of the fill opening 19.

(12) Furthermore, a lifting of the cover 8 may be improved by supporting the onflow edge 24 of the cover 8 by means of elastic clasps 15 with respect to the cargo space structure 2 and thereby holding open the air inlet opening 6 at least partly. For reasons of clarity, only three elastic clasps 15 are indicated in FIG. 3; in practice, however, a plurality of elastic clasps 15 should be arranged distributed over the entire width of the fill opening 19.

(13) In the representation of FIG. 3, the upper sail 21 and the lower sail 22 are each connected to the cargo space structure 2. However, it would likewise be possible to join together the upper sail 21 and the lower sail 22 in lateral end sections 8a of the cover 8 and then join the respective end section 8a to the cargo space structure 2 as a single layer.

(14) Between lower sail 22 and roof wall 2a it is possible to provide ribs 13 as spacing elements 10 running substantially in the direction of travel x, being advisedly made also of a flexible flat structure 9. The ribs 13 thereby enable a vertical movement of the cover 8 between a lowered and a raised position. The ribs 13 also serve for the fastening of the cover 8 to the cargo space structure 2. In place of or in addition to the ribs 13, belts 11 may also be used as spacing elements 10, which can support extremely high loads and furthermore are not subject to twisting.

(15) The spacing element 10 may also alternatively be formed as a cable 12, which is preferably arranged in the region of the air inlet opening 6. The cable 12 provides lower air resistance, but only enables a pointlike bearing of the load as compared to a rib 13 extending in a line.

(16) The difference in level of the air conduction duct 5 between the air inlet opening 6 and the air outlet opening 7 is bridged by means of the apron 14, which is arranged on the cover 8. The apron 14 is also made from a flexible flat structure 9 and thereby allows the vertical movement of the cover 8.

(17) FIG. 4 shows an air conduction element 4 in top view, wherein the cover 8 has a conically tapering section 17 opposite the direction of travel x. This serves to build up a back pressure beneath the cover 8 and thereby assist the raising of the cover 8.

LIST OF REFERENCE SYMBOLS

(18) 1 Load-carrying vehicle 1a Tractor unit 1b Semitrailer 2 Cargo space structure 2a Roof wall 2b Side wall 2c Rear wall 2d Front wall 3 Rear region of cargo space structure 4 Air conduction element 5 Air conduction duct 6 Air inlet opening 7 Air outlet opening 8 Cover 8a Lateral end section 9 Flexible flat structure 10 Spacing element 11 Belt 12 Cable 13 Rib 14 Apron 15 Elastic clasps 16 Airfoil 17 Conical section 18 Pocket 19 Fill opening 20 Struts 21 Upper sail 22 Lower sail 23 Fifth wheel coupling 24 Onflow edge x Direction of travel