Test bench device for measuring a vehicle and system

Abstract

The invention relates to a test bench device (2) for measuring a vehicle (3) in an air flow (200), comprising a work space (10) for accommodating measuring technology (11) and a floor unit (20) for separating the work space (10) from a test space (4) in which the vehicle (3) can be exposed to the air flow (200), with at least one floor element (21) for defining a floor plane (20.1) of the test bench device (2) and at least one receiving element (22) on which a wheel (3.1) of the vehicle (3) can be positioned in order to define a flow area (201) around the wheel (3.1) for the air flow (200) to flow around on the receiving element (22). The invention further relates to a system (1).

Description

[0001] The invention relates to a test bench device for measuring a vehicle in an air flow and a system.

[0002] To realistically examine and measure vehicles on the test track in the wind tunnel, the wheels are rotated using wheel drive units (RAE) of the treadmill scale. The wheels are mounted on steel belts, for example, that operate at the wind speed to be simulated. A treadmill scale is known, for example, from document DE 10 2008 036 315 B4. In this case, the airflow around the floor is influenced by suction openings.

[0003] In addition, however, it is known for the steel belts in treadmill scales to run on air bearings. This air usually escapes laterally under the belts and interacts with the airflow of the vehicle being tested, such as the airflow in the area of ​​the wheels. In addition, there is often a further gap around the RAEs to a subjacent scale cellar that contains the scale's measuring technology. The RAEs belong to the weighed part of the scale, and the turntable surrounding them belongs to the unweighed part. Consequently, the gaps are advantageous in that the weighed and unweighed parts do not come into contact. Furthermore, there should be a certain amount of play between the weighed and unweighed parts to allow relative movement when the weighed and unweighed parts rotate and to avoid frictional contact when they come into contact. This gap may allow foranother air flow from the scale cellar, which interacts with the flow of the vehicle being examined and can influence the measurement.

[0004] From DE 10 2011 106 197 A1 a receiving element in the form of a belt unit for a test bench device is known, in which an extraction unit on the extraction unit is intended to prevent the influence of the air flow around the motor vehicle to be tested by lifting the conveyor belt.

[0005] From CN 1 17 871 021 B a test facility (“wind tunnel test device”) is known in which the boundary layer under the vehicle to be tested is modified by means of a suction device in such a way that fewer disturbing effects occur.

[0006] It is an object of the present invention to at least partially remedy the above-mentioned disadvantages known from the prior art. In particular, it is an object of the present invention to improve a design of a test bench device for measuring a vehicle for measurements with greater accuracy, particularly with regard to air flow.

[0007] The above object is achieved by a test bench device having the features of claim 1, as well as a system having the features of claim 10. Further features and details of the invention emerge from the respective subclaims, the description, and the drawings. Features and details described in connection with the test bench device according to the invention naturally also apply in connection with the system according to the invention, and vice versa, so that with regard to the disclosure of the individual aspects of the invention, reference is always made to each other.

[0008] According to a first aspect of the invention, a test bench device for measuring a vehicle in an air flow is provided. The test bench device has a work space for accommodating measuring equipment and a floor unit for separating the work space from a test space in which the vehicle can be exposed to the air flow. The floor unit comprises at least one floor element for defining a floor plane of the test bench device and at least one receiving element on which a wheel of the vehicle can be positioned in order to define a flow area around the wheel for the air flow to flow around, in particular at the receiving element. The receiving element is mounted in the work space by an air bearing, by means of which the receiving element can be brought to an operating height for measuring the vehicle.The base element and the receiving element are separated by a gap that is in fluid communication with the air bearing, through which at least a partial flow of the air bearing escapes into the gap when the receiving element is raised to the operating height, in particular by activating the air guide. Furthermore, the test bench device has an air guide system through which the partial flow in the gap can be discharged into an air discharge area, in particular outside the flow area.

[0009] The vehicle is, in particular, a motor vehicle and / or an aircraft with a landing gear. The test chamber may preferably comprise a wind tunnel to expose the vehicle to the air flow.

[0010] The measurement technology can comprise one or more sensors for measuring the vehicle, in particular a vehicle reaction to an air flow in the test chamber. For example, the measurement technology can comprise a scale, preferably in the form of a multi-component scale. The working chamber can be formed, for example, by an opening and / or a cavity in a floor of the test chamber. In particular, the working chamber can form a scale cellar.

[0011] The floor element can, for example, comprise a floor covering, particularly in the form of a floor plate, to form the floor level. The work space is preferably arranged below the floor unit, so that the vehicle with the measuring equipment can be positioned above the work space.

[0012] The receiving element can form a standing surface for the wheel. The standing surface can be supported by the air bearing. The air bearing can comprise at least one air bearing, in particular for each wheel of the vehicle. The air bearing is preferably arranged in the working space. The receiving element can delimit the working space and / or be flush with the floor element. The operating height can be understood in particular as a height of the standing surface in relation to the floor surface and / or the working space. For example, the operating height can be defined by the standing surface being flush with the floor surface or having a predetermined distance from the floor surface. The mounting of the receiving element by the air bearing can preferably be understood to mean that the receiving element can be supported by the air bearing during operation of the test stand device by an air cushion generated by the air bearing.It can be provided that the receiving element rests on a bearing element of the air bearing in a deactivated state of the test stand device.

[0013] The partial flow can comprise an air flow from the air bearing that escapes the air cushion. For example, the partial flow at the air bearing can be directed laterally at least partially or completely toward the gap. The fluid communication connection can be formed, in particular, by an air duct and / or a free space. The gap can preferably be connected to the air bearing via the fluid communication connection.

[0014] For example, the gap can surround the air bearing so that the partial flow can escape into the gap.

[0015] The air discharge region differs, in particular, spatially from the flow-around region. For example, the air discharge region can comprise a region which is at a distance from the flow-around region, by means of which an influence on the air flow in the flow-around region is prevented or almost prevented. The discharge of the partial flow can be carried out actively or passively by the air duct system. For example, active discharge of the partial flow can comprise suction. Passive discharge of the partial flow can, for example, comprise guiding, i.e. in particular deflecting, the partial flow through one or more air ducts within the air duct system.

[0016] Within the scope of the present invention, it has been recognized that a partial flow of an air bearing can influence the measurement of the vehicle through lateral longitudinal vortices in the flow around the wheel if the partial flow reaches the flow around the wheel. The partial flow can therefore be discharged by the air guidance system, in particular to prevent any influence on the flow around the wheel. This consequently makes it possible to use an air bearing for a test bench device in which contact between a weighed and unweighed part, e.g. through seals, is not possible without changing the measurement result when measuring the vehicle. The air bearing can therefore achieve a high level of accuracy when measuring the vehicle and at the same time at least partially prevent the partial flow of the air bearing from reducing this accuracy again.In addition, the air guidance system can also prevent an air flow from the working area from entering the flow area around the wheel.

[0017] In a test stand device according to the invention, it can preferably be provided that the receiving element is designed as a drive belt by means of which the wheel of the vehicle can be driven. The drive belt has, in particular, a flat extension. Advantageously, the drive belt can have a closed or almost closed surface. The drive belt can be a steel and / or plastic belt, for example. The standing surface for the wheel can be formed by a run of the drive belt. Furthermore, the drive belt can be mounted on at least two rollers. One of the rollers can form a drive roller which is operatively connected to a drive, e.g. in the form of an electric motor. The drive belt can create a stable standing surface for the vehicle. The air cushion can advantageously be formed by a surface below the drive belt.The gap can also allow the drive belt to move relative to the floor element without contact.

[0018] Furthermore, in a test bench device according to the invention, it can advantageously be provided that the drive belt has a drive direction along which the drive belt can be moved relative to the wheel when driving the wheel, wherein the gap extends parallel to the drive direction along the drive belt, in particular so that the partial flow can be discharged to the air discharge region on an end face of the wheel. It can be provided that the strand moves along the drive direction. The end face of the wheel can in particular be formed by an outer side of the wheel. Furthermore, the end face can be aligned perpendicular to a vehicle axis when the wheel is mounted on the vehicle. In particular, the flow region can be formed on the end face. The gap can preferably extend circumferentially around the drive belt.Especially on the sides of the drive belt that are parallel to the drive direction, the distance between the gap and the wheel can be small if the drive belt is narrow. Without the air guidance system to discharge the partial flow in the gap, the airflow around the wheel could be significantly affected in this area. Furthermore, the space for the air bearings below the drive belt can be open on the sides parallel to the drive direction. The air guidance system can prevent the partial flow from escaping there.

[0019] Within the scope of the invention, it is further conceivable for the floor unit to have a plurality, preferably four, receiving elements in the form of drive belts for driving a respective wheel of the vehicle, each of which is surrounded by the floor element and a gap between the floor element and the respective receiving element, wherein the air guidance system is designed to discharge partial flows, preferably from an air bearing assigned to the respective receiving element, in each gap, in particular into the air discharge area. The air discharge area can comprise a plurality of connected or unconnected sub-areas into which the partial flows are discharged. For example, it can be provided that the air guidance system directs each partial flow into a separate sub-area or all partial flows into the same area. Furthermore, it can be provided that the floor unit has a central belt which runs beneath the vehicle.For example, the test bench device can be designed as a five-belt system comprising four drive belts and a central conveyor belt. The central belt can be used to simulate the air flow beneath the vehicle, particularly during travel. The central belt can also be supported by an air bearing and / or have a gap, particularly a circumferential one, through which air can escape from the working space. Preferably, the air guidance system is designed to discharge a further partial flow into the air discharge area in the gap of the central belt.

[0020] Furthermore, in a test bench device according to the invention, it can advantageously be provided that the air guidance system for discharging the partial flow has a suction device for generating a pressure difference between the gap and the air discharge region. For this purpose, the suction device can advantageously be arranged between the gap and the air discharge region. The suction device can comprise a suction pump for generating the pressure difference. The suction device can preferably be arranged in the working space. Furthermore, the suction device can be connected to one or more lines of the air discharge system to establish a fluid communication connection between the suction device and the gap. The partial flow can be actively discharged by the suction device. Furthermore, the proportion of the discharged partial flow in the air quantity in the gap can be increased as a function of the pressure difference.Thus, the suction device can be used to control the discharge of the partial flow. For example, a control unit of the test bench device can be configured to control the suction device for the discharge of the partial flow in order to coordinate the discharge of the partial flow with a measurement process for measuring the vehicle.

[0021] Preferably, in a test bench device according to the invention, it can be provided that the air guidance system for discharging the partial flow has a guide element which extends along the gap, i.e. in particular along at least a section of the gap, in order to guide the partial flow in the direction of the air discharge region. Preferably, the guide element can be designed as a separate component and arranged in the gap. For example, the guide element can be retrofitted in a modular manner for the floor element. The guide element can, for example, comprise a guide plate, in particular in the form of a baffle. The guide element can advantageously protrude at least partially or completely into the gap in order to at least partially close the gap. In particular, the guide element can thus reduce a cross-section of an opening in the gap to the flow-around region and thereby deflect the partial flow.This can significantly reduce the amount of air flowing from the air bearing into the flow area. The guide element can preferably be arranged in one plane and / or parallel to the base element. However, it is also conceivable for the guide element to be arranged at least partially overlapping the receiving element in order to cover the gap, in particular completely. For this purpose, the guide element can be arranged obliquely to a floor plane formed by the base element. Furthermore, it can be provided that the receiving element is arranged below a floor plane of the base element and the guide element is arranged flat with the base element, i.e. in particular flush with the floor plane. By arranging the receiving element below the base element, the guide element can cover the receiving element and at the same time form a flat floor surface with the base element.An air duct through which the partial flow can be discharged can be formed or formed through the guide element. For example, the guide element can be attached to the base element and at least partially cover the gap. The partial flow can be guided below the guide element. The guide element thus enables passive discharge of the partial flow. This allows the partial flow to be easily directed away from the flow area and toward the air discharge area.

[0022] Within the scope of the invention, it is further conceivable for the air guidance system for discharging the partial flow to have an air duct for directing the partial flow in the direction of the air discharge region, with at least one deflection for influencing a direction of the partial flow, in particular wherein the air duct is at least partially formed by the guide element. For example, the guide element can form a wall of the air duct. The air duct can be part of a line system of the air guidance system. In this case, the guide element can form one side of the air duct, for example. It is conceivable for the air discharge region to be provided in the working space, in particular in a lower part of the working space. The deflection can deflect the partial flow away from the upper region in order to avoid influencing the flow area.

[0023] Preferably, in a test bench device according to the invention, it can be provided that the air duct has a duct section which defines a guide direction for guiding the partial flow parallel to the floor unit, in particular wherein the duct section has an air outlet for guiding the partial flow into the test chamber at a predefined distance from the wheel. It can be provided that a deflection is provided in a flow direction before and / or after the duct section. The predefined distance can prevent the partial flow from reaching the flow area directly. For example, the distance can be dimensioned such that the partial flow does not generate any air turbulence in the flow area. The distance can therefore lead the partial flow into the test chamber. As a result, the air guidance system in the work chamber can be designed to be compact and the available installation space can be used, e.g.be used for measurement technology.

[0024] Preferably, in a test bench device according to the invention, the guide element can be provided with a curvature by which the partial flow can be deflected toward the working chamber. For example, the guide element with the curvature can be designed as a guide baffle. The curvature can preferably comprise a partial circle, e.g., in the form of a quarter circle. If the air discharge area is provided in the working chamber, the guide element with the curvature can already be sufficient to deflect the partial flow from the flow-around area and direct it to the air discharge area. Thus, the guidance of the partial flow can be achieved in a simple manner.

[0025] According to a further aspect of the invention, a system is provided. The system comprises a vehicle, a workspace for accommodating measurement equipment, and a test space in which the vehicle can be exposed to the air flow. Furthermore, the system comprises a test bench device according to the invention for measuring the vehicle in an air flow.

[0026] Thus, a system according to the invention offers the same advantages as those already described in detail with reference to a test bench device according to the invention. For measuring the vehicle, the vehicle can be mounted on receiving elements of the test bench device.

[0027] Further advantages, features, and details of the invention will become apparent from the following description, which describes exemplary embodiments of the invention in detail with reference to the drawings. The features mentioned in the claims and in the description may be essential to the invention individually or in any combination. They show schematically: Fig. 1 an air bearing of a test stand device according to the invention with a wheel of a vehicle in a side view, Fig. 2 to 4 exemplary designs of an air guidance system of the test bench device in a front view, and Fig. 5 a system according to the invention with the test bench device and the vehicle.

[0028] In the following description of some embodiments of the invention, the same reference numerals are used for the same technical features even in different embodiments.

[0029] Fig. Figure 1 shows a side view of a first exemplary embodiment of a receiving element 22 of a test bench device 2 according to the invention. A wheel 3.1 of a vehicle 3 is positioned on the receiving element 22 in an air flow 200 in order to perform a measurement process for the vehicle 3, in particular the wheel 3.1 in the air flow 200.

[0030] The test bench device 2 is designed for measuring a vehicle 3 in the air flow 200 with a working space 10 for accommodating a measuring technology 11. A system 1 according to the invention with the test bench device 2 and the vehicle 3 is shown by way of example in Fig. 5. The test bench device 2 comprises a floor unit 20 for separating the work space 10 from a test space 4, in which the vehicle 3 can be exposed to the air flow 200. For this purpose, the floor unit 20 has at least one floor element 21 for defining a floor plane 20.1 of the test bench device 2 and several, here four, receiving elements 22 on which the wheels 3.1 of the vehicle 3 are positioned. Furthermore, a central belt 23 is arranged below the vehicle 3, by means of which a relative movement of the vehicle 3 to the floor plane 20.1 can be simulated.

[0031] Each of the receiving elements 22 is further, as in Fig. 1, is mounted in the working space 10 by an air bearing 12. The air bearing 12 allows the respective receiving element 22 to be brought to an operating height 13 for measuring the vehicle 3. Furthermore, the receiving element 22 is designed as a drive belt, by which the wheel 3.1 of the vehicle 3 can be driven. The drive belt has a drive direction 22.1, along which the drive belt can be moved relative to the wheel 3.1 when driving the wheel 3.1.

[0032] As in the Fig. 2 to 4 in a front view, a flow area 201 of the wheel 3.1 for the air flow 200 to flow around is defined on the receiving element 22. It is further shown that the base element 21 and the receiving element 22 are spaced apart by a gap 31. The gap 31 extends parallel to the drive direction 22.1 along the drive belt, so that the partial flow 202 can be discharged to the air discharge area 32 on one end face of the wheel 3.1. The gap 31 is preferably provided circumferentially around the receiving element 22. The gap 31 is in fluid communication with the air bearing 12, via which at least a partial flow 202 of the air bearing 12 escapes into the gap 31 when the receiving element 22 is brought to the operating height 13.

[0033] In order to prevent the partial flow 202 from completely entering the flow area 201 and thereby influencing the measurement of the vehicle 3, the test bench device 2 has an air guidance system 30 through which the partial flow 202 in the gap 31 can be discharged into an air discharge area 32 outside the flow area 201.

[0034] As in Fig. 2, the air guidance system 30 for discharging the partial flow 202 can have a suction device 33 for generating a pressure difference between the gap 31 and the air discharge area 32. For example, the air discharge area 32 can be provided in the working space 10. The suction device 33 can therefore be designed to direct the partial flow 202, for example, into the working space 10.

[0035] Furthermore, the air guidance system 30 for discharging the partial flow 202 may comprise a guide element 34 which is arranged in the gap 31 in order to guide the partial flow 202 in the direction of the air discharge area 32. In Fig. 2, the guide element 34 is arranged such that the guide element 34 guides the partial flow 202 to the suction device 33. For this purpose, the guide element 34 is further shaped such that the guide element 34 protrudes beyond the receiving element 22. As a result, the partial flow 202 can be almost completely suctioned off. In the present exemplary embodiment, the guide element 34 is arranged obliquely to the floor plane 20.1 for this purpose. Furthermore, the air guidance system 30 has an air duct 35 for guiding the partial flow 202 in the direction of the air discharge area 32 and / or the suction device 33 with at least one deflection 35.1 for influencing a direction of the partial flow 202. The air duct 35 is at least partially formed by the guide element 34.

[0036] In particular, if the receiving element 22 is located at least partially or completely below the floor plane 20.1 and / or below the floor element 21, the guide element 34 can, as an alternative to an inclined position of the guide element 34, also be arranged flat, ie in particular flush in the floor plane 20.1, with the floor element 21 in order to nevertheless at least partially cover the receiving element 22.

[0037] As in the Fig. 3 and Fig. 4, the guide element 34 can also enable the partial flow 202 to be discharged into the air discharge area 32 without the suction device 33. Thus, the guide element 34 forms with the base element 21 in the embodiment according to Fig. 3 the air duct 35 with a duct section 35.2, which defines a guide direction 35.3 for guiding the partial flow 202 parallel to the floor unit 20. The duct section 35.2 has an air outlet 36 for guiding the partial flow 202 into the test chamber 4 at a predefined distance from the wheel 3.1. According to the embodiment according to Fig. 4, the guide element 34 has a curvature 37, by means of which the partial flow 202 can be passively deflected in the direction of the working chamber 10.

[0038] Thus, the air guidance system 30 is particularly designed to discharge partial flows 202 in each of the gaps 31 around the receiving elements 22 and preferably in a gap 31 around the central band 23 into the air discharge area 32.

[0039] The above explanation of the embodiments describes the present invention exclusively by way of examples. Of course, individual features of the embodiments can be freely combined with one another, provided they are technically feasible, within the scope of protection defined by the patent claims, without departing from the scope of the present invention. List of reference symbols 1 system 2 test bench device 3 vehicles 3.1 Wheel 4 Experimental room 10 work space 11 Measurement technology 12 Air bearings 13 Operating height 20 floor unit 20.1 Ground level 21 Floor element 22 receiving element 22.1 Drive direction 23 Middle Band 30 Air duct system 31 gap 32 Air discharge area 33 Suction device 34 Guide element 35 Air duct 35.1 Deflection 35.2 Canal section 35.3 Direction of guidance 36 Air outlet 37 Curvature 200 air flow 201 Flow area 202 Partial flow

Claims

[1] Test stand device (2) for measuring a vehicle (3) in an air flow (200), comprising a working space (10) for accommodating a measuring device (11) and a floor unit (20) for separating the working space (10) from a test space (4) in which the vehicle (3) can be exposed to the air flow (200), with at least one floor element (21) for defining a floor plane (20.1) of the test stand device (2) and at least one receiving element (22) on which a wheel (3.1) of the vehicle (3) can be positioned in order to define a flow area (201) around the wheel (3.1) for the air flow (200), wherein the receiving element (22) is mounted in the working space (10) by means of an air bearing (12), by means of which the receiving element (22) can be brought to an operating height (13) for measuring the vehicle (3), wherein the base element (21) and the receiving element (22) are spaced apart by a gap (31) which is in fluid communication with the air bearing (12), via which at least a partial flow (202) of the air bearing (12) escapes into the gap (31) when the receiving element (22) is brought to the operating height (13), wherein an air guidance system (30) is provided, by means of which the partial flow (202) in the gap (31) can be discharged into an air discharge region (32) outside the flow-around region (201). [2] Test stand device (2) according to claim 1, characterized by that the receiving element (22) is designed as a drive belt by which the wheel (3.1) of the vehicle (3) can be driven. [3] Test stand device (2) according to claim 1 or 2, characterized bythat the drive belt has a drive direction (22.1) along which the drive belt is movable relative to the wheel (3.1) when driving the wheel (3.1), wherein the gap (31) extends parallel to the drive direction (22.1) along the drive belt, so that the partial flow (202) can be discharged to the air discharge area (32) on one end face of the wheel (3.1). [4] Test stand device (2) according to one of the preceding claims, characterized by that the floor unit (20) has a plurality of receiving elements (22) in the form of drive belts for driving a respective wheel (3.1) of the vehicle (3), which are each surrounded by the floor element (21) and a gap (31) between the floor element (21) and the respective receiving element (22), wherein the air guidance system (30) is designed to discharge partial flows (202) in each gap (31) into the air discharge area (32). [5] Test stand device (2) according to one of the preceding claims, characterized by that the air guidance system (30) for discharging the partial flow (202) has a suction device (33) for generating a pressure difference between the gap (31) and the air discharge area (32). [6] Test stand device (2) according to one of the preceding claims, characterized by that the air guidance system (30) for discharging the partial flow (202) has a guide element (34) which extends along the gap (31) in order to guide the partial flow (202) in the direction of the air discharge area (32). [7] Test stand device (2) according to one of the preceding claims, characterized by that the air guidance system (30) for discharging the partial flow (202) has an air duct (35) for directing the partial flow (202) in the direction of the air discharge area (32) with at least one deflection (35.1) for influencing a direction of the partial flow (202), wherein the air duct (35) is at least partially formed by the guide element (34). [8] Test stand device (2) according to one of the preceding claims, characterized by that the air duct (35) has a duct section (35.2) which defines a guide direction (35.3) for guiding the partial flow (202) parallel to the floor unit (20), wherein the duct section (35.2) has an air outlet (36) for guiding the partial flow (202) into the test chamber (4) at a predefined distance from the wheel (3.1). [9] Test stand device (2) according to one of the preceding claims, characterized by that the guide element (34) has a curvature (37) by means of which the partial flow (202) can be deflected in the direction of the working space (10). [10] System (1) comprising a vehicle (3), a work space (10) for accommodating measuring equipment (11), a test chamber (4) in which the vehicle (3) can be exposed to the air flow (200), and a test bench device (2) according to one of the preceding claims for measuring the vehicle (3) in an air flow (200).

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