Motor vehicle having a windshield and a roof element located above the windshield

Abstract

The invention relates to a motor vehicle (100) having a windshield (102) and a roof element (104) located above the windshield (102), wherein the roof element (104) has a front overhang (106) relative to an upper edge (108) of the windshield (102) of the motor vehicle (100) in the vehicle longitudinal direction (x). At least one through-opening (114) is formed in the underside of the overhang (106).

Description

[0001] Description

[0002] Motor vehicle with a windshield and a roof element arranged above the windshield

[0003] The invention relates to a motor vehicle according to the preamble of claim 1, in particular a motor vehicle that is at least partially autonomous and has a roof element.

[0004] From DE 102021 122 866 A1 a roof module for forming a vehicle roof on a motor vehicle is known, which forms at least one roof skin of the vehicle roof that functions as an outer sealing surface.

[0005] US patent 11,964,616 B2 discloses a roof covering system for a vehicle operating in one or more partially or fully autonomous self-driving modes. The roof covering system is arranged to be positioned above the roof, in particular 10-50 mm above the roof, of the vehicle.

[0006] US patent 2019 / 0248421 A1 discloses a roof-mounted arrangement for an autonomous commercial vehicle. This roof-mounted arrangement includes a lighting assembly.

[0007] From WO 2021 / 186414 A1, an air conditioning system with a housing is known, wherein the air conditioning system can be used in vehicles and has a lighting device.

[0008] From DE 102022 105 578 A1 a flow guidance device for a motor vehicle with at least one flow guidance element is known, wherein a driving wind can be diverted in a predetermined direction by the flow guidance element.

[0009] The invention is based on the objective of providing a motor vehicle with a roof element in which the roof element is used in an aerodynamically efficient manner.

[0010] The problem is solved according to the invention by the features of the independent claims. Further practical embodiments and advantages of the invention are described in connection with the dependent claims. A motor vehicle according to the invention has a windshield and a roof element arranged above the windshield. The roof element projects forward beyond the upper edge of the windshield of the motor vehicle in the longitudinal direction of the vehicle. The motor vehicle is, in particular, an at least partially autonomous vehicle with a plurality of sensors, which are usually arranged in the roof element. In particular, the motor vehicle is a fully autonomous vehicle.

[0011] According to the invention, at least one through-opening is formed in the underside of the overhang.

[0012] The underlying principle of this arrangement is that air accumulating in the "corner area" between the upper edge of the windshield and the underside of the roof element can flow through the opening into the roof element while driving. This optimally utilizes the fluid dynamic properties of the structure and improves the overall aerodynamic characteristics of the vehicle. In other words, the invention is based on the idea that, from an aerodynamic perspective, concave surfaces directly exposed to the airflow should generally be avoided. However, the overhang creates precisely such a concave surface, resulting in increased dynamic pressure.Through the opening, which is preferably located precisely in the area of ​​the roof element, especially in the area of ​​the overhang, where the air accumulates during driving, this air can be "drained" and thus the aerodynamically detrimental stagnation pressure can at least be reduced or even completely avoided or diverted.

[0013] According to one practical embodiment, a passage channel is formed within the roof element, connecting the passage opening to an outlet opening. The outlet opening is oriented rearward in the longitudinal direction of the vehicle within the roof element. In other words, this creates a flow channel extending longitudinally along the vehicle, through which air can flow, particularly while the vehicle is in motion, thus improving the vehicle's aerodynamic properties. Specifically, this embodiment is based on the consideration that a partially high dynamic pressure occurs in the area of ​​the passage opening during driving. A negative pressure arises in the area of ​​the outlet opening, i.e., in the rear region of the roof element when viewed in the direction of travel. These pressure differences advantageously promote airflow through the passage channel.

[0014] Alternatively, multiple passage channels can be arranged within the roof element. These multiple passage channels can either connect to a common opening or each have its own opening. Similarly, the multiple passage channels can also share a common outlet opening or each have its own outlet opening.

[0015] According to another practical embodiment, the passage channel connects the passage opening and the outlet opening without any changes in direction greater than 60°, in particular greater than 40°, preferably greater than 20°. This means that the passage channel preferably has few changes in direction, i.e., curves or inclines, and in particular runs essentially straight. This means that after entering, the air can flow through the passage channel with no or only a very slight change in direction, in particular with changes in direction of less than 10°. This has little effect on the airflow within the passage channel and thus further improves the aerodynamic properties of the vehicle.

[0016] In a practical embodiment, the through-channel has, at least in some sections, a constant cross-section or a cross-section that widens or narrows in the direction of flow. The term "direction of flow" as used in the invention refers to the direction of the air flowing through the through-channel. This means that the air preferably flows into the through-channel through the opening and exits the through-channel through the outlet opening. The different channel cross-sections allow the through-channel to be adapted to the specific aerodynamic requirements of the vehicle. For example, a narrowing channel cross-section can achieve a higher flow velocity within the through-channel, which can have a positive effect on the vehicle's aerodynamics.

[0017] According to another practical embodiment, louvers are arranged in the passage channel. The louvers serve to prevent rainwater from entering the passage channel, particularly in the area of ​​the passage opening and / or the outlet opening. Especially in the case of an outlet opening open from above, the louvers are preferably arranged in the area of ​​the outlet opening in such a way that rainwater flows from louver to louver.

[0018] According to another practical embodiment, the forward projection in the longitudinal direction of the vehicle has a length of at least 5 cm, preferably at least 10 cm, and more preferably at least 15 cm. Regardless of the aforementioned lengths, the bumper of the motor vehicle always forms the foremost point of the motor vehicle.

[0019] Alternatively or additionally, an angle between the vehicle window and the overhang has a value of less than 90°, preferably less than 85° and more preferably less than 80°.

[0020] In such embodiments, the through-channel has proven to be particularly advantageous, as it allows a sufficient amount of air, which would otherwise collect between the upper edge of the windscreen and the underside of the roof element, to be "drained".

[0021] A practical further development stipulates that at least one heat exchanger element must be arranged within the flow channel. This heat exchanger element can be, for example, a heat exchanger in the sense of an (engine) radiator for cooling a vehicle's drive motor, an air conditioning condenser, for cooling the vehicle's interior, or – if two or more heat exchanger elements are arranged within the flow channel – both.

[0022] If two or more heat exchanger elements are arranged within the flow channel, they are preferably arranged in parallel (side by side) or in series (one after the other) within the flow channel. Alternatively, each heat exchanger element can be located in its own separate flow channel.

[0023] Alternatively or additionally, further units can be arranged in the passageway, where permeation by air flowing through the passageway is advantageous.

[0024] This embodiment offers the additional advantage of improved component packaging, in addition to the efficient use of air flowing through the passageway for cooling. For example, an engine radiator in the vehicle's engine compartment can be eliminated if it is arranged within the passageway as described above. This allows for greater flexibility in the arrangement of other components in the engine compartment. Furthermore, the front of the vehicle can have a larger, closed surface area than if the engine radiator were installed in the engine compartment and exposed to airflow. A larger, closed surface area at the front of the vehicle can also have a beneficial effect on the vehicle's aerodynamics.

[0025] According to another practical embodiment, a fan is arranged within the passageway. The fan assists the air flowing through the passageway to ensure sufficient cooling of the heat exchanger element located within it. This design has proven particularly advantageous when the vehicle is traveling at low speeds.

[0026] In one practical embodiment, one or more lines of the at least one heat exchanger element are routed through one or more pillars of the vehicle. These lines may, for example, be refrigerant lines of the heat exchanger element designed as an air conditioning condenser, and / or they may be air lines and / or air ducts that direct the cooled air into the vehicle's interior, provided an additional heat exchanger element is installed in the roof structure. Alternatively or additionally, the lines may be coolant lines that are routed through the one or more pillars of the vehicle into the engine compartment to cool the vehicle's drive engine.Alternatively or additionally, one or more lines can also convey warm air from the vehicle's interior and heated coolant from the engine compartment to the respective heat exchanger element. The one or more pillars of the vehicle could be, for example, an A-pillar, B-pillar, and / or C-pillar.

[0027] To achieve efficient airflow, the through-opening and / or the outlet opening, according to a practical embodiment, extends at least half the width of the vehicle. In particular, a single through-opening and / or outlet opening is at least 25 mm wide, preferably at least 50 mm wide, and especially at least 100 mm wide. The number of through-openings is preferably selected such that one or more through-openings extend over at least half the width of the vehicle. It is also possible to have only one through-opening, which extends at least half the width of the vehicle, for example, at least 1000 mm, if the vehicle width is a maximum of 2000 mm.

[0028] Further practical embodiments of the invention are described below in connection with the drawings. They show:

[0029] Fig. 1 shows a schematic side view of a motor vehicle according to a first embodiment of the invention; and

[0030] Fig. 2 shows a schematic side view of the motor vehicle according to a second embodiment of the invention.

[0031] In the figures, identical or equivalent components are always marked with the same reference symbols. The vehicle's longitudinal direction (x-direction) is marked with x and the vehicle's vertical direction (z-direction) with z.

[0032] Figure 1 shows a first embodiment of a motor vehicle 100 according to the invention.

[0033] The motor vehicle 100 has a windshield 102 and a roof element 104 arranged above the windshield 102. The roof element 104 in turn has a projection 106 towards the front in the longitudinal direction (x-direction) of the vehicle 100 relative to an upper edge 108 of the windshield 102.

[0034] The motor vehicle 100 is, in particular, a motor vehicle 100 that is at least partially autonomous. In the illustrated embodiment, the motor vehicle 100 is a small van. However, it goes without saying that the invention is not limited to such types of motor vehicles. Rather, the invention can also be applied to other types, such as, but not limited to, sedans and / or coupes as well as station wagons.

[0035] Sensors 110 and / or cameras 112 are arranged in the overhang 106 of the roof element 104. These sensors and / or cameras provide driving and environmental information for the motor vehicle 100, and in particular for the at least semi-autonomous and especially the fully autonomous operation of the motor vehicle 100. Both the sensors 110 and the cameras 112 are only schematically symbolized by rectangles in the figures. An angle α spans between the windshield 102 and the overhang 106, in particular the underside of the overhang 106. This angle α has a value of less than 90°, in particular less than 85°, preferably less than 80°. Furthermore, the overhang 106 has a length of at least 5 cm, preferably at least 10 cm, and preferably at least 15 cm in the longitudinal direction x of the vehicle, either alternatively or additionally.

[0036] Furthermore, a through-opening 114 is formed in the underside of the overhang 106. The through-opening 114 serves to "drain" air that accumulates during driving in the area of ​​the upper edge 108 of the windshield 102 and the underside of the overhang 106. The resulting reduction in dynamic pressure has a beneficial effect on the aerodynamic properties of the motor vehicle 100.

[0037] Furthermore, the roof element 104 has an outlet opening 116. The through-opening 114 and the outlet opening 116 are connected to each other by a through-channel 118. In particular, the two openings 114 and 116 are fluidically connected. This means that the air accumulating in front of the through-opening 114 flows into the through-channel 118 during travel, through it to the outlet opening 118, and then out of the through-channel 118 at the rear of the overhang 106.

[0038] The through-opening 114 and / or the outlet opening 116 extends at least over half the width of the motor vehicle 100. In particular, individual through-openings 114 and / or outlet openings 116 are at least 25 mm wide, preferably at least 50 mm wide and preferably at least 100 mm wide.

[0039] In order to favorably influence the flow velocity of the air flowing through the passage channel 118, the passage channel 118 has at least in some areas a channel cross-section Q that narrows or widens in the direction of flow S.

[0040] For example, and with reference to Fig. 1, the through-channel 118 has a widening channel cross-section Q in the region of the through-opening 114, preferably viewed in the flow direction S after the through-opening 114. The channel cross-section Q then narrows in the flow direction S towards the outlet opening. Fig. 2 shows a second embodiment of the motor vehicle 100 according to the invention in a schematic side view.

[0041] The motor vehicle 100 also has a windshield 102 and a roof element 104. The roof element 104 has the overhang 106 already explained with reference to Fig. 1.

[0042] Likewise, a passage channel 118 is formed within the roof element 104, connecting a passage opening 114 with an outlet opening 116. The passage opening 114 is also formed on the underside of the overhang 106 in the area of ​​an upper edge 108 of the windshield 02.

[0043] The difference from the embodiment shown in Fig. 1 is that a heat exchanger element 120 is arranged within the passage 118. The heat exchanger element 120 shown in Fig. 2 is an engine radiator for a drive motor 122 of the motor vehicle 100, which is represented schematically by a rectangle. The air flowing through the passage 118 cools a coolant that is transported by means of lines 124 through the roof element 104 and / or one or more columns 126 of the motor vehicle 100 from the drive motor 122 to the heat exchanger element 120 and back. The aforementioned lines 124 are shown schematically by a line in Fig. 2.

[0044] Furthermore, to efficiently utilize the effect of the passage channel 118 even at low driving speeds, a fan 128 is arranged within the passage channel 118. This supports the airflow through the passage channel 118 and thus also through the heat exchanger element 120, particularly at low driving speeds.

[0045] Furthermore, louvers 130 are arranged in the area of ​​the outlet opening 116, which prevent rainwater from entering the outlet opening 116, oriented rearward in the longitudinal direction x of the vehicle, and thus from entering the passage channel 118. For clarity, only three louvers 130 are shown in Fig. 2. However, it is self-evident that the application is not limited to exactly three louvers 130 and that any number of louvers 130, adapted in particular to the respective size of the outlet opening 116, can be provided. In all other respects, the embodiment according to Fig. 2 corresponds to the embodiment according to Fig. 1 with regard to structure and function, so reference is made to its description.

[0046] The features of the invention disclosed in the present description, the drawings, and the claims can be essential for realizing the invention in its various embodiments, both individually and in any combination. The invention can be varied within the scope of the claims and taking into account the knowledge of the person skilled in the art. For example, the embodiment described above according to Fig. 2, particularly with regard to the described heat exchanger element 120, the fan 128, and the fins 130, is not to be understood as restricting the invention to considering these three components only together. Rather, it is also possible for only the heat exchanger element 120, without the fan 128, to be arranged within the passage 118.Alternatively, the motor vehicle 100 may be provided with only the heat exchanger element 120 and the fan 128, but without any fins 130 at the outlet opening 116. Likewise, it may be provided with only a heat exchanger element 120 and the fins 130, but without a fan 128.

[0047] Reference symbol list

[0048] 100 motor vehicles

[0049] 102 Windscreen

[0050] 104 roof element

[0051] 106 Overhang

[0052] 108 Top edge of the windshield

[0053] 110 sensors

[0054] 112 cameras

[0055] 114 Passage opening

[0056] 116 Outlet opening

[0057] 118 Through channel

[0058] 120 Heat exchanger element

[0059] 122 Drive motor

[0060] 124 Line

[0061] 126th pillar of the motor vehicle

[0062] 128 fans

[0063] 130 slats a angle between overhang and windshield x vehicle longitudinal direction z vehicle vertical direction

[0064] S Flow direction

[0065] Q Channel cross-section

Claims

Patent claims 1. Motor vehicle (100) with a windscreen (102) and a roof element (104) arranged above the windscreen (102), wherein the roof element (104) has a projection (106) towards an upper edge (108) of the windscreen (102) of the motor vehicle (100) in the longitudinal direction (x) of the vehicle, characterized in that at least one through-opening (114) is formed in the underside of the projection (106).

2. Motor vehicle (100) according to claim 1, wherein a passage channel (118) is formed within the roof element (104) which connects the passage opening (114) with an outlet opening (116), wherein the outlet opening (116) is formed in the roof element (104) oriented towards the rear in the longitudinal direction (x) of the vehicle.

3. Motor vehicle (100) according to claim 2, wherein the passage channel (118) connects the passage opening (114) and the outlet opening (116) without changes in direction greater than 60°, in particular greater than 40°.

4. Motor vehicle (100) according to one of claims 2 or 3, wherein the passage channel (118) has at least in some areas a channel cross-section (Q) that is constant or widens in the direction of flow (S) or narrows in the direction of flow (S).

5. Motor vehicle (100) according to one of the preceding claims, wherein lamellae (130) are arranged in the passage channel (118).

6. Motor vehicle (100) according to one of the preceding claims, wherein the projection (106) in the longitudinal direction (x) of the vehicle has a length of at least 5 cm and / or an angle (a) between the vehicle window (102) and the projection (106) has a value of less than 90°.

7. Motor vehicle (100) according to one of the preceding claims, wherein at least one heat exchanger element (120) is arranged within the passage channel (118).

8. Motor vehicle (100) according to one of claims 2 to 7, wherein a fan (128) is arranged within the passage channel (118).

9. Motor vehicle (100) according to one of claims 7 or 8, wherein one or more lines (124) of the at least one heat exchanger element (120) are guided through one or more columns (126) of the motor vehicle (100).

10. Motor vehicle (100) according to one of the preceding claims, wherein the through-opening (114) and / or the outlet opening (116) extends at least over half the width of the motor vehicle (100).

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