Vehicle roof rack foot, roof rack equipped therewith, and motor vehicle equipped therewith

Abstract

Vehicle roof rack foot (10, 10'), with - a crossbeam receptacle (30, 30') designed to accommodate a crossbeam (40) of a roof truss (5), - a fastening section (25, 25') designed to be attached to a roof rail (20) or roof channel of a roof (3) of a motor vehicle (1), and - a connecting section (35, 35') connecting the crossbeam receptacle (30, 30') and the fastening section (25, 25'), wherein - the cross member receptacle (30, 30'), the connecting section (35, 35') and the fastening section (25, 25'), viewed in the main direction of travel (F) of the motor vehicle (1), each have an upstream front surface (45-1, 50-1, 55-1) and a downstream rear surface (45-2, 50-2, 55-2), and - wherein the respective front surface (45,-1, 50-1, 55-1) is designed as an arc-shaped section, characterized in that it has a slenderness ratio (λ) such that - the slenderness ratio (λ) of the fastening section (25, 25') is 1.3, where this slenderness ratio (λ) is defined as the quotient of length (I) to thickness (d) of the fastening section (25, 25') in a cross-sectional plane extending in the longitudinal direction (x) and transverse direction (y) of the vehicle, and - the slenderness ratio (λ) of the cross member support (30, 30') is 3.5, where this slenderness ratio (λ) is defined as the quotient of length (I) to thickness (d) of the cross member support (30, 30') in a cross-sectional plane extending in the longitudinal direction (x) and vertical direction (z) of the vehicle.

Description

[0001] The present invention relates to a vehicle roof rack foot according to claim 1, a roof rack equipped therewith according to claim 8 and a correspondingly equipped motor vehicle according to claim 9.

[0002] Roof racks are known for transporting loads on the roofs of motor vehicles. The loads, for example roof boxes, are attached to cross members of the roof racks, which in turn are mounted to roof rails or roof channels of the respective vehicle roofs by means of vehicle roof rack feet. Corresponding examples are known from EP 2 017 129 A2, EP 2 746 108 A1, WO 2010 / 030198 A1, DE 20 2012 012 771 U1 and EP 2 570 304 A1. To reduce the air resistance associated with these known roof racks, an aerodynamic design of the respective cross members is provided, as can be seen from the three aforementioned prior art documents.

[0003] Further vehicle roof rack feet are known from DE 198 11 004 A1, DE 694 06 883 T2, DE 199 00 217 A1, DE 10 2008 052 828 A1 and WO 2016 / 042319 A1.

[0004] Finally, a vehicle roof rack foot is known from DE 28 05 858 A1, with - a crossbeam mount designed to accommodate a crossbeam of a roof truss, - a fastening section designed to be attached to a roof rail or roof channel of a motor vehicle roof, and - a connecting section connecting the crossbeam mount and the fastening section, wherein - the cross member mounting, the connecting section and the fastening section, viewed in the main direction of travel of the motor vehicle, each have an upstream front surface and a downstream rear surface, and - wherein the respective front surface is designed as an arc-shaped section.

[0005] The object of the present invention is to provide means by which the air resistance of a roof rack can be further reduced.

[0006] This problem is solved by a vehicle roof rack base with the features of claim 1. Advantageous embodiments of the invention are contained in the dependent claims.

[0007] The vehicle roof rack foot is initially designed such that its respective front surface is rounded. This reduces the air resistance of the vehicle roof rack foot according to the invention. The term "round" should not be interpreted too narrowly, as it generally refers to an arc-shaped section. Therefore, the crossbeam mount, the connecting section, and the mounting section each have an arc-shaped section on their front surface. The arc length and arc radius of the front surface can be constant or variable when considered across the entire front surface of the crossbeam mount. The same applies to the arc lengths and arc radii of the connecting section and the mounting section, respectively, in the area of ​​the front surface.Furthermore, the arc lengths and / or arc radii of the crossbeam mounting, the connecting section and the fastening section can each be individually, partially or entirely the same or different.

[0008] The vehicle roof rack foot according to the invention is characterized in that it has a slenderness such that - the slenderness ratio of the fastening section is 1.3, where this slenderness ratio is defined as the quotient of length to thickness of the fastening section in a cross-sectional plane extending in the longitudinal and transverse directions of the vehicle, and - the slenderness ratio of the cross member mount is 3.5, where this slenderness ratio is defined as the quotient of length to thickness of the cross member mount in a cross-sectional plane extending in the longitudinal and vertical directions of the vehicle.

[0009] The air resistance of the vehicle roof rack foot according to the invention is thereby advantageously further reduced when viewed in the main direction of travel.

[0010] According to a preferred embodiment, the respective front surface of the cross member receptacle, connecting section and fastening section is larger than their respective rear surface, so that the air resistance of the vehicle roof rack foot is further reduced.

[0011] In principle, the respective rear surfaces of the crossbeam receptacle, the connecting section, and / or the fastening section can be round. Here, too, the term "round" should not be interpreted too narrowly and generally refers to an arc-shaped section. Thus, the crossbeam receptacle, the connecting section, and the fastening section each have an arc-shaped section on their respective rear surfaces. The arc length and arc radius of the rear surface can be constant or variable when considered across the entire rear surface of the crossbeam receptacle. The same applies to the arc lengths and arc radii of the connecting section and the fastening section, respectively. Furthermore, the arc lengths and / or arc radii of the crossbeam receptacle, the connecting section, and the fastening section can be the same, partially, or entirely the same or different on their respective rear surfaces.

[0012] According to a preferred embodiment, at least one rear surface is designed to be flat. This advantageously forms a flow-damping separation edge, further reducing the air resistance of the vehicle roof rack base according to the invention when viewed in the main direction of travel. Furthermore, a vehicle roof rack base designed according to the invention is quieter in operation, i.e., when a suitably equipped motor vehicle is in motion, than comparable devices known from the prior art.

[0013] Advantageously, the front surface of the fastening section, the front surface of the cross member receptacle, and / or the front surface of the connecting section are rounded and each have a radius of curvature R. According to a preferred embodiment, the following relationship essentially applies: 10≤R≤40

[0014] This radius of curvature R can be, but does not necessarily have to be, the same for the aforementioned components. Particularly advantageously, the radius of curvature of the crossbeam mounting is essentially 10 mm and the radius of curvature of the base is essentially 40 mm.

[0015] According to a further preferred embodiment, the vehicle roof rack foot is characterized in that the front surface has a radius of curvature R and the vehicle roof rack foot has a length l such that 0.15≤R / I≤0.4

[0016] This ratio may, but does not necessarily have to, be the same for the fastening section, the crossbeam mounting and / or the connecting section.

[0017] The vehicle roof rack foot is advantageously characterized by the fact that the front surface has a width b and the radius of curvature R essentially with the following relationship. 0.45≤R / b≤0.5

[0018] This ratio can, but does not necessarily have to, be the same for the fastening section, the crossbeam receptacle, and / or the connecting section. Particularly advantageously, the ratio R / b of the crossbeam receptacle is essentially 0.45 and that of the fastening section is essentially 0.5.

[0019] According to a preferred embodiment, the mounting section, the crossbeam receptacle, and / or the connecting section taper downstream from their respective front surfaces. The taper, that is, the ratio of the length of the aforementioned components at point x, where the taper begins, to their width d at that point, is essentially characterized by the following relationship: 1≤x / d≤3

[0020] This ratio can, but does not necessarily have to, be the same for the fastening section, the crossbeam receptacle, and / or the connecting section. Particularly advantageously, the ratio x / d of the crossbeam receptacle is essentially 3 and that of the fastening section is essentially 1.

[0021] The aforementioned task is also solved by a roof rack with a vehicle roof rack base of the type previously disclosed. The advantages mentioned above apply accordingly.

[0022] The aforementioned problem is also solved by a motor vehicle equipped with a roof rack of the type disclosed above. The advantages mentioned above apply accordingly.

[0023] The following is a detailed, non-prejudicative, and in particular limiting, description of exemplary embodiments of the present invention with reference to the accompanying figures. Fig. Figure 1 shows a section of a motor vehicle according to the invention with a roof rack according to the invention shown in a perspective oblique view. Fig. Figure 2 shows a first embodiment of a vehicle roof rack foot according to the invention in a perspective oblique view from the front. Fig. Figure 3 shows a second embodiment of a vehicle roof rack foot according to the invention in a perspective view from below.

[0024] The following is made with reference to Fig. Sections 1 to 3 provide a detailed, non-prejudicative, and in particular limiting, description of exemplary embodiments of the present invention. Identical elements are designated with identical reference numerals unless otherwise indicated.

[0025] In Fig. Figure 1 shows a motor vehicle 1 according to the invention with a roof rack 5 according to the invention mounted on a roof 3. The main direction of travel F of the motor vehicle 5 is symbolized by the corresponding arrow. Thus, the front area V or rear area H of the motor vehicle 1 (not shown here) and its right side S or left side B are located according to the directions shown in the figure. Fig. 1 designated position.

[0026] The roof rack 5 has, in a manner known per se, two vehicle roof rack feet 10, 15, which are attached to two spaced-apart roof rails 20 located on the right and left sides of the vehicle S and B respectively (of which only the right roof rail 20, facing the main direction of travel F, is shown). It is understood that attachment to a roof channel (not shown here) is also possible.

[0027] Each vehicle roof rack foot 10 or 10' has a mounting section 25 or 25', a cross member receptacle 30 or 30', and a connecting section 35 or 35' that connects the mounting section 25 or 25' to the cross member receptacle 30 or 30'. The mounting sections 25 and 25' are attached to the roof rail 20 (or the roof channel, not shown) in a manner known per se. The two cross member receptacles 30 and 30' accommodate a cross member 40 in a manner known per se, to which a load (not shown), for example a roof box, can be mounted.

[0028] Fig. Figure 2 shows a first embodiment of a vehicle roof rack foot 10 according to the invention in a perspective oblique view from the front. Starting from the main direction of travel F, this foot is exposed to an airflow (symbolically represented by a streamline v). On the upstream side, the vehicle roof rack foot 10 comprises a front surface 45-1 on the mounting section 25, a front surface 50-1 on the cross member receptacle 30, and a front surface 55-1 on the connecting section 35. On the downstream side, the vehicle roof rack foot 10 comprises a rear surface 45-2 on the mounting section 25, a rear surface 50-2 on the cross member receptacle 30, and a rear surface 55-2 on the connecting section 35.

[0029] Each of the front surfaces 45-1, 50-1, and 55-1 is rounded when viewed in the direction of flow and has a radius of curvature R. Due to the chosen perspective, only the radius of curvature R1 of the front surface 55-1 and the radius of curvature R2 of the back surface 55-2 are visible in this figure. The upstream radius of curvature R1 is larger than the downstream radius of curvature R2, so that the front surface 55-1 is larger than the back surface 55-2. This also applies analogously to the other front surfaces 45-1 and 50-1 and back surfaces 45-2 and 50-2.

[0030] The transition from fastening section 45-1, connecting section 35 towards crossbeam receptacle 50-1 tapers in the z-direction.

[0031] Again Fig. As can also be seen from Figure 2, the maximum length of the crossbeam support 30 is equal to I, while its maximum thickness is equal to d. In the chosen example, the slenderness ratio λ, i.e., the quotient of I to d, is 3.5, while the quotient of R1 to I is 0.1.

[0032] In Fig. Figure 3 shows a second embodiment of a vehicle roof rack foot 10 according to the invention in a perspective view from below. Unlike the one in Fig. In the embodiment shown in Figure 2, the rear surface of the fastening section 45-2, the rear surface 50-2 of the crossbeam receptacle, and the rear surface of the connecting section 55-2 are provided with a sharp edge 45-3, 50-3, and 55-3, respectively, which each act as a shear edge. For these, the respective rounded edges R2 would therefore be theoretically infinitely large. In the embodiment shown here, the slenderness ratio λ is 1.3, while the ratio of R1 to I is 0.4.

[0033] It is understood that deviations from the illustrated embodiments, particularly with regard to their dimensions, for example the length l, the thickness d and the radii of curvature R, may be provided. Thus, according to an advantageous embodiment, the length l of a vehicle roof rack foot 10, 10' can be essentially 145 mm if a rounded rear surface 45-2, 50-2, 55-2 is present; if a rounded rear surface 45-2, 50-2, 55-2 is not present, but rather a chamfered edge 45-3, 50-3, 55-3 is present, the length l is essentially 100 mm, with the maximum thickness being 70 mm in both cases.

[0034] In any case, the fastening sections 25, 25', crossbeam receptacles 30, 30' and connecting sections 35, 35' are designed such that they each have a teardrop shape when viewed along their respective length, with the respective front surface 45-1, 50-1 or 55-2 being round. Furthermore, it is possible to design the respective fastening sections 25, 25', crossbeam receptacles 30, 30' and connecting sections 35, 35 with an asymmetrical profile instead of a symmetrical one.

[0035] A particularly preferred embodiment of the present invention is characterized by relationships which are essentially distinguished as follows: Rounding radius R1 of the crossbeam mounting 50-1: 20 mm Rounding radius R2 of the fastening section 45-1: 40 mm Thickness d of the crossbeam mounting 50-1: 20 mm Thickness d of the fastening section 45-1: 70 mm Length l of the crossbeam mount 50-1: 75 mm Length l of the fastening section 45-1: 100 mm Slenderness ratio λ of the crossbeam mount 50-1: 3.5 Slenderness ratio λ of the fastening section 45-1: 1.3 Recess x / d of the crossbeam mount 50-1: 3 Retraction x / d of the fastening section 45-1: 1 Reference symbol list 1 motor vehicle 3 roof 5 vehicle roof racks 10, 10' Vehicle roof rack foot 20 roof rails 25, 25' fastening section 30, 30' Crossbeam mounting 35, 35' connecting section 40 crossbeams 45-1 Front surface of the mounting section 45-2 Rear surface of the fastening section 45-3 edge at the fastening section 50-1 Front surface of the crossbeam mount 50-2 Rear surface of the crossbeam mount 50-3 Edge of the crossbeam mount 55-1 Front surface of the connecting section 55-2 Rear surface of the connecting section 55-3 Edge of the connecting section B left side of vehicle F Main direction of travel of the motor vehicle H Rear area R1, R2 Rounding radius S right side of vehicle V Front area d thickness l Length of a vehicle roof rack foot v direction of airflow x, y, z axes of a known, vehicle-specific Cartesian coordinate system λ Slenderness level

Claims

[1] Vehicle roof rack foot (10, 10'), with - a cross member holder (30, 30') which is designed to receive a cross member (40) of a roof rack (5), - a fastening section (25, 25') which is designed to be fastened to a roof rail (20) or a roof channel of a roof (3) of a motor vehicle (1), and - a connecting section (35, 35') connecting the cross member holder (30, 30') and the fastening section (25, 25'), wherein - the cross member receptacle (30, 30'), the connecting section (35, 35') and the fastening section (25, 25'), viewed in the main direction of travel (F) of the motor vehicle (1), each have an upstream front surface (45-1, 50-1, 55-1) and a downstream rear surface (45-2, 50-2, 55-2), and - wherein the respective front surface (45-1, 50-1, 55-1) is formed as an arcuate section, characterized bythat it has a slenderness ratio (λ) such that - the slenderness ratio (λ) of the fastening section (25, 25') is 1.3, wherein this slenderness ratio (λ) is defined as the quotient of length (I) to thickness (d) of the fastening section (25, 25') in a cross-sectional plane extending in the vehicle longitudinal direction (x) and the vehicle transverse direction (y), and - the slenderness ratio (λ) of the cross member holder (30, 30') is 3.5, wherein this slenderness ratio (λ) is defined as the quotient of length (I) to thickness (d) of the cross member holder (30, 30') in a cross-sectional plane extending in the vehicle longitudinal direction (x) and vehicle vertical direction (z). [2] Vehicle roof rack base (10, 10') according to claim 1, characterized by that the respective front surface (45-1, 50-1, 55-1) is larger than the respective rear surface (45-2, 50-2, 55-2). [3] Vehicle roof rack foot (10, 10') according to claim 1 or 2, characterized bythat at least one rear surface (45-2, 50-2, 55-2) is flat. [4] Vehicle roof rack foot (10, 10') according to one of the preceding claims, characterized by that the respective front surface (45-1, 50-1, 55-1) has a rounding radius R with the following relationship: 10≤R≤40 [5] Vehicle roof support base (10, 10') according to one of the preceding claims, characterized by that the respective front surface (45,-1, 50-1, 55-1) has a rounding radius (R) and the vehicle roof carrier foot (10, 10') has a length (I) such that 0.15≤R / I≤0.4 [6] Vehicle roof support base (10, 10') according to one of the preceding claims, characterized by that the respective front surface (45,-1, 50-1, 55-1) has a width (b) and the rounding radius (R) with the following relationship. 0.45≤R / b≤0.5 [7] Vehicle roof support base (10, 10') according to one of the preceding claims, characterized bythat the respective front surface (45,-1, 50-1, 55-1) has a taper x / d with the following relationship: 1≤x / d≤3 [8] Roof rack (5), characterized by a vehicle roof rack foot (10, 10') according to one of the preceding claims. [9] Motor vehicle (1), characterized by a roof rack (5) according to claim 8.

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