Test stand for automotive drivetrains

Abstract

The present invention relates to a test stand (100) for a drivetrain of a motor vehicle (20). The test stand (100) includes a load motor (110) having a motor housing (111) and a motor shaft (112), a load sensor (120), and a mounting module (130). The motor shaft (112) is drivingly connected to a hub (21) of the motor vehicle (20). The load sensor captures the load transmitted from the motor shaft to the hub. The drivetrain test stand (1) comprises an axial side (115) of the motor housing (11) facing the hub (21) and a mounting module (130) connected to each other in a non-rotatable manner, the motor shaft is configured as a hollow shaft (112) through which a shaft is led and which is connected non-rotatably to the hub directly or indirectly, a load sensor is arranged on the axial side (116) of the motor housing (111) opposite the hub, and the hollow shaft can be drivingly connected to the shaft via the load sensor.

Description

Technical Field

[0001] The present invention relates to a test bench for an automotive drive train as described in the generic concept of claim 1.

Background Art

[0002] Transmission test benches or drive train test benches for testing an automotive transmission or the entire automotive drive train are known from the prior art. This type of test bench is typically used for quality control in order to detect functional disorders in the drive train at an early stage by means of a series of load tests. Typical functional disorders are caused, for example, by components with play, such as gears, synchronizer rings, synchronizer bodies, disks of multi-plate clutches, and shafts, which may be excited to deflect or vibrate. In the context of this type of functional test, the acoustic behavior and the quality of shifting are also usually tested. Furthermore, this type of test bench is also used in the development and continuous improvement of automotive drive trains.

[0003] In this context, DE4328537C2 describes a transmission test bench. This transmission test bench comprises a first servo motor functioning as a drive motor and a second servo motor functioning as a brake motor. The drive motor is connected via a clutch to the input shaft of the transmission of the motor vehicle to be tested, and in particular, its rotational speed is controlled by a PC. As a result, it is possible to simulate any rotational speed curve. The brake motor is connected via a further clutch to the output shaft of the transmission of the motor vehicle to be tested. The rotational speed of the brake motor is also controlled via the PC. The rotational speed curve simulated by the PC is the rotational speed curve measured in an actual road test. Thus, the transmission of a motor vehicle can be tested according to DE4328537C2 before being installed in the motor vehicle.

[0004] DE10328461A1 discloses a vehicle test stand comprising one load machine for each drivable wheel of a vehicle. The load machine is connected to the rim of the vehicle's wheel, in this case, directly, for example, via wheel bolts, or indirectly, for example, via a belt drive. As a result, the load machine can drive and brake the drivetrain. The vehicle test stand of DE10328461A1 further includes a frame structure. Through this frame structure, the vehicle and the load machine can be raised and aligned with each other. During the test process, the vehicle is fully supported by the frame structure. As a result, the wheels of the vehicle do not come into contact with the ground.

[0005] However, known automotive test stands have drawbacks, particularly when they are designed to test drivetrains already installed in vehicles, as they require a relatively large footprint and rely on complex and expensive mechanical support structures. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] DE4328537C2 [Patent Document 2] DE10328461A1 [Overview of the project] [Problems that the invention aims to solve]

[0007] The object of this invention is to propose an improved test stand for automobile drivetrains. [Means for solving the problem]

[0008] According to the present invention, this problem is solved by the test stand for an automobile drivetrain described in claim 1. Advantageous embodiments will become apparent from the dependent claims.

[0009] The present invention relates to a test stand for an automobile drivetrain. The test stand includes at least one load motor having a motor housing and a motor shaft, at least one load sensor, and at least one mounting module. The motor shaft is configured to be drive-coupled to a hub of an automobile. The load sensor is configured to capture the load transmitted from the motor shaft to the hub. The test stand according to the present invention is configured such that the axial side of the motor housing facing the hub and at least one mounting module are connected to each other in a non-rotatable manner, the motor shaft is configured as a hollow shaft, and the shaft guided through the hollow shaft is configured to be directly or indirectly connected to the hub in a non-rotatable manner, the load sensor is located on the axial side of the motor housing opposite the hub, and the hollow shaft is drive-coupled to the shaft via the load sensor.

[0010] In other words, the present invention describes a test stand suitable for testing the drivetrain of an automobile. The automobile may similarly be an automobile driven by an electric motor, or an automobile driven in the conventional manner.

[0011] The test stand comprises, for this purpose, at least one load motor having a motor housing and a motor shaft. The load motor is advantageously an electric motor. Electric motors have a relatively compact configuration, have a wide rotational speed range, and, advantageously, have maximum torque over a wide rotational speed range, particularly compared to internal combustion engines. Only when reaching the so-called "corner point" in the high rotational speed range does the torque decrease indirectly in proportion to the further increasing rotational speed due to the increasing weakening of the magnetic field.

[0012] Preferably, at least one load motor is configured as a permanently excited synchronous motor. The synchronous motor particularly advantageously includes a relatively large number of pole pairs, for example, 12 or more. This type of synchronous motor is also known as a so-called synchro-torque motor. This allows the load motor to be configured to be relatively compact and short. As a result, the center of gravity of the load motor is located very close to the vehicle chassis, which is an advantage.

[0013] Each load motor is, advantageously, assigned its own inverter. The inverter is configured, for example, three-phase.

[0014] At least one load motor is provided with a motor housing. The load motor can be mounted via the motor housing, for example, on a base or on a device provided for that purpose. Alternatively or additionally, the motor housing is also configured to allow the load motor to be positioned or supported, for example, via its so-called a-side or b-side.

[0015] The motor housing may, for example, be equipped with a water cooling system.

[0016] Finally, at least one load motor may include a motor shaft. The motor shaft provides the torque and rotational speed generated by the load motor. The motor shaft can be driven-coupled to one of the hubs of the vehicle's wheels. As a result, torque and rotational speed can be introduced from the motor shaft to the hub. Both torque and rotational speed represent the mechanical power that can load the drivetrain under test. Therefore, torque and rotational speed represent the load on the drivetrain that occurs during the test.

[0017] In the sense of this invention, a drive coupling is understood to mean a mechanical connection for transmitting mechanical power. Torque and rotational speed can be converted within the range of transmission from the load motor to the hub. That is, the load motor provides, for example, a first rotational speed and a first torque. The first rotational speed and first torque represent a first power. Within the range of transmission of the first power, the first torque can be converted to a second torque, and the first rotational speed can be converted to a second rotational speed. However, the first power remains unchanged by transmission. In other words, the definition of a motor shaft being drive-coupled to a hub, or drive-coupled, does not stipulate that there must be a direct mechanical connection between the motor shaft and the hub, particularly a connection in a non-rotatable state. Rather, the drive coupling may include gears or individual gears or other intermediate elements.

[0018] Furthermore, the test stand includes at least one load sensor. The load sensor is configured to capture the load transmitted from the motor shaft to the hub. This could be, for example, rotational speed, torque, or both.

[0019] Preferably, at least one load sensor is configured as a torque sensor and / or force sensor. The rotational speed of the load motor can also be captured, for example, via its control electronics, particularly an inverter. Therefore, it is advantageous that the load sensor is configured to capture torque or force acting via a lever. From the known rotational speed and the torque thus determined, for example, power or load can be determined.

[0020] Furthermore, the test stand includes at least one mounting module. The at least one mounting module can be non-rotatably connected to the axial side of the motor housing facing the hub, via connecting means provided for this purpose, such as a flange connection. Preferably, the axial side facing the hub is the so-called A side of the load motor. The mounting module is advantageously mounted to the hub of the vehicle, either at the wheel position or like a wheel.

[0021] Preferably, the connection of the mounting module to the motor housing is located radially outward on the outermost radial edges of both the mounting module and the motor housing, particularly in the area occupied by the vehicle's hub. This allows the connection to support relatively larger torques, while allowing the vehicle's hub to remain rotatable relative to the motor housing. There is also no need to introduce torque or rotational speed into the drivetrain via the drive shaft. This advantageously establishes a short and therefore very rigid connection. As a result, vibrations strong enough to disrupt the test process can be avoided during the operation of the test stand. Furthermore, there is the advantage that the common center of gravity of the load motor and the mounting module is very close to the contact point of the mounting module. This avoids further undesirable influences on the test behavior of the drivetrain.

[0022] According to the present invention, the motor shaft is further configured as a hollow shaft, and a shaft is provided through which the shaft is guided. This shaft can then be connected to the hub in a non-rotatable manner, either directly or indirectly. Finally, a load sensor is positioned on the axial side of the motor housing opposite the hub, which is preferably the so-called b side, and drives the hollow shaft to this shaft. Thus, a drive connection can be established from the hollow shaft through the load sensor to the shaft located within the hollow shaft, and finally to the hub of the automobile.

[0023] At the same time, the load motor is supported via a mounting module, just like the motor vehicle being tested via its suspension. The mounting module is placed on the base, where the gravity acting on the mounting module is supported. The base can have a particularly high coefficient of friction with respect to the mounting module in order to enable the transmission of high torque from the load motor to the mounting module.

[0024] Furthermore, at least one mounting module can be connected to the base in a frictionally or form-fitting manner. For example, by using a tension belt whose ends are firmly connected to the base to clamp the mounting module over its running surface, the adhesion on the base of the mounting module can be further enhanced. In order to further improve the adhesion on the base of the mounting module, the mounting module can also be arranged on the base, for example, by using bolts that are arranged on the ground and penetrate the mounting module radially from the outside.

[0025] Thus, the present invention describes a very compact test bench for testing the drive train of a motor vehicle, which can directly connect the load motor to the hub of the motor vehicle without an intermediate shaft. This results in the advantage that the required test space is significantly smaller, particularly because a bulky and expensive test bench or a corresponding frame structure is not required to hold the motor vehicle and the load motor and align them with each other. In particular, the complex and time-consuming alignment or adjustment of the drive train or the motor vehicle to the test bench is no longer required. A further substantial advantage of the present invention is that, in the test process using the test bench according to the present invention, the motor vehicle to be tested is supported exclusively by the chassis during the test process, so that, in particular, the characteristics of the chassis of the motor vehicle to be tested are not affected as much as possible. Therefore, advantageously, the chassis-specific characteristics such as the spring deflection behavior, the handling behavior, and similar characteristics can be tested very realistically.

[0026] Advantageously, according to the invention, the test bench includes, for each drivable wheel of the motor vehicle, a respective load motor, a respective load sensor, and a respective mounting module. Thus, the complete drive train of the motor vehicle can be tested in a single test drive.

[0027] According to a preferred embodiment of the invention, at least one mounting module has concentric openings. The hub is accessible from the side facing at least one load motor through the concentric openings. The concentric openings are, in this case, advantageously at least large enough for the hub of the motor vehicle to open completely. Thereby, the shaft guided through the hollow shaft can be directly connected to the hub in a non-rotatable state. For example, the shaft can comprise a plate-shaped end part having a perforated ring corresponding identically to the perforated ring of the hub for this purpose. In particular, the shaft can first be arranged in a non-rotatable state on the hub. Then, the load motor having a hollow shaft can be slid onto the shaft. The mounting module having concentric openings can, in this case, be arranged rotatably, for example, on the axial side of the load motor facing the hub of the motor vehicle. However, other constructive or arrangement forms of at least one mounting module and the shaft are also conceivable.

[0028] According to an alternative preferred embodiment of the present invention, at least one mounting module comprises a radially outer portion and a radially inner portion. The inner portion is rotatably held by the outer portion. The inner portion is configured to be non-rotatably connected to the hub of the vehicle. The outer portion is configured to be non-rotatably connected to the axial side of the motor housing facing the hub. In this case, at least one mounting module is composed of two parts, i.e., the radially inner portion of the mounting module is rotatable relative to the radially outer portion of the mounting module. As a result, even in this case, at least one load motor can be non-rotatably connected to the mounting module, i.e., the outer portion. Therefore, even in this case, at least one load motor can be supported in the mounting module. At the same time, the mounting module can be connected to the hub not only via the load motor and further via a hollow shaft, load sensor, and shaft, but also directly and non-rotatably connected to the hub via the inner portion rotatable relative to the outer portion. This allows the mounting module to be attached to the vehicle like a normal wheel, and then the vehicle, together with the mounted mounting module, can be positioned or aligned in a simple manner, for example, by pushing it. Therefore, the load motor can be easily assembled into the vehicle's drivetrain. However, other configurations or arrangements of at least one mounting module and axle are also possible.

[0029] According to a particularly preferred embodiment of the present invention, the shaft can be connected to the inner portion in a non-rotatable manner. The inner portion is connected to the hub in a non-rotatable manner. Therefore, the load provided by the load motor can be transmitted through the shaft to the inner portion of the mounting module and from there to the vehicle's drivetrain via the hub.

[0030] According to a particularly preferred embodiment of the present invention, the shaft is a component of the inner portion of at least one mounting module. Advantageously, the shaft and the inner portion may even be integrally formed. Thus, the load motor can be centered and aligned, for example, during assembly in a mounting module or automobile, by being guided along the shaft using its hollow shaft. The shaft guided through the hollow shaft is then connected to a load sensor on side b of the load motor. As a result, a drive connection exists from the load motor to the hub via the load sensor.

[0031] According to a particularly preferred embodiment of the present invention, rotation of the inner portion relative to the outer portion can be blocked. Blocking can be done, for example, by moving a bolt or slide provided for this purpose, or by positioning a clamping element such that relative movement of the outer portion relative to the inner portion is blocked. This provides the advantage that the vehicle can move under its own power and be easily positioned and aligned for testing. For example, a correspondingly lockable mounting module can be attached to each wheel of the vehicle under test. The vehicle can then travel from the mounting location of the mounting module to the testing location within a test venue, for example, a large hall.

[0032] According to a further preferred embodiment of the present invention, a pneumatic tire is placed on at least one mounting module. In this case, the mounting module on the base exhibits support behavior that closely corresponds to the support behavior that occurs during normal driving of the vehicle. This improves the quality of the test because the behavior of the drivetrain under test conditions more closely resembles the behavior of the drivetrain during normal driving of the vehicle.

[0033] Preferably, pneumatic tires, which are also approved for road use by automobiles, are placed on the mounting module.

[0034] According to an alternative preferred embodiment of the present invention, a rubber coating is placed on at least one mounting module. The rubber coating also allows the mounting module to be supported on the base in a relatively realistic manner. However, in this case, unlike with pneumatic tires, it is not necessary to separately select and attach an appropriate pneumatic tire to the mounting module each time. Instead, the rubber coating can be firmly and permanently placed on the mounting module.

[0035] According to a further preferred embodiment of the present invention, the hollow shaft is provided with a rotary union for introducing a coolant and a passage for the coolant to flow through the hollow shaft. Thus, the rotor can be cooled from the inside during the operation of the load motor.

[0036] According to a further preferred embodiment of the present invention, at least two axially spaced bearings are arranged radially between the hollow shaft and the shaft to receive lateral or axial forces. This ensures that, in particular, the weight of at least one load motor is absorbed by the bearings provided for this purpose and does not act on the load sensor. Thus, only the torque to be captured acts on the load sensor. As a result, the measurement accuracy of the load sensor is improved. In this case, the bearings function only to receive lateral or axial forces because there is no relative rotation between the shaft and the hollow shaft.

[0037] According to a further preferred embodiment of the present invention, the test stand further comprises at least one motor support configured to support the inclination moment of at least one load motor. The load motor is connected to the mounting module only via the axial side, preferably side a, and is supported exclusively via the mounting module. Thus, a relatively small inclination moment acts on the load motor due to the common center of gravity of the load motor and the mounting module being close to the contact point of the mounting module. Nevertheless, this can adversely affect the test. This inclination moment is advantageously absorbed by the motor support. In this case, the motor support can be positioned below the motor housing, for example, on the axial side of the motor housing opposite the hub, preferably in the area of ​​side b of the motor housing, to support the load motor from below. Similarly, it is also conceivable to mount the motor support so that it holds the load motor from above, i.e., so that the load motor rests on the motor support. In the latter case, the motor support can be configured, for example, as a cable, particularly as a wire cable, for cost-effective and simple purposes.

[0038] When a motor support holds a load motor from above, the motor support may include a compensating element, particularly one positioned in the power flow and containing a spring to which pre-tension can be applied. In this case, advantageously, the inclination moment to be compensated, or the force to be compensated in correspondence with the inclination moment, can be set via the settable pre-tension of the spring. This ensures that the inclination moment is not overcompensated.

[0039] According to a further preferred embodiment of the present invention, the test stand further includes at least one support plunger. The support plunger is adjustable in three spatial directions and / or rotatable around three axes. The support plunger is configured to support a mounting module. Alternatively, the test stand further includes at least one hexapod-type actuator device. The actuator device is configured to adjust the hub in three spatial directions and / or rotate around three axes. Thus, by appropriately operating the support plunger along the vertical axis, for example, rough terrain during the vehicle's journey can be simulated. Similarly, almost all other possible base effects, particularly in relation to the steering motion of the vehicle's steerable wheels, can also be simulated via the support plunger. The hexapod-type actuator device preferably engages with the vehicle's hub and can similarly simulate rough terrain during the journey and almost all other possible base effects. The hexapod-type actuator device, as its name suggests, includes six actuators. These can be configured, for example, as hydraulic cylinders. Therefore, it becomes possible to conduct tests on the drivetrain, especially those that are closer to real-world conditions.

[0040] The present invention will be described below illustratively based on embodiments shown in the drawings. [Brief explanation of the drawing]

[0041] [Figure 1] This is a schematic diagram illustrating a test stand and a vehicle under test, both known in the prior art for testing the drivetrain of an automobile. [Figure 2] This is an illustrative schematic diagram of possible embodiments of a test stand according to the present invention for an automobile drivetrain and an automobile under test. [Figure 3] This is a schematic diagram illustrating details of possible embodiments of a test stand according to the present invention. [Figure 4] This is a schematic diagram illustrating further possible embodiments of the test stand according to the present invention. [Figure 5] This is a schematic diagram illustrating yet another possible embodiment of the test stand according to the present invention. [Figure 6] This is a schematic diagram illustrating yet another possible embodiment of the test stand according to the present invention. [Figure 7] This is a schematic diagram illustrating possible embodiments of the mounting module according to the present invention. [Figure 8] This is a schematic diagram illustrating yet another possible embodiment of the test stand according to the present invention. [Modes for carrying out the invention]

[0042] Identical objects, functional units, and similar components are shown with the same reference numerals throughout the figures. These objects, functional units, and similar components are constructed to be identical in terms of their technical features unless otherwise stated, either expressly or implicitly, in the description.

[0043] Figure 1 illustrates, schematicly, a test stand 10 and a vehicle 20 under test, known in the prior art for testing the drivetrain of a vehicle 20. In this case, the drivetrain is already fully mounted on the vehicle 20. The known test stand 10 comprises two load units 11. Each of these load units 11 is connected to the hubs 21 of the drivable wheels of the vehicle 20 via a connecting shaft 12. However, a test stand of the same type 10 having four load units 11 is also known, particularly for all-wheel drive vehicles. Each load unit 11 comprises a terminal box 14 located on an electric drive motor 13. The terminal box 14 houses cables that supply electrical energy to the electric drive motor 13. Each drive motor 13 is located on a frame 15. The frame 15 is laterally adjustable to accommodate different vehicle type track widths. The vehicle 20 is typically lifted onto a support element 16 and placed thereon by a lifting device, such as a crane. Each support element 16 has a bearing for fixing to the wheel hub. The structure and spatial requirements of the known test stand 10 are relatively large. Because the wheels are not attached to the hub 21 of the automobile 20, the automobile 20 cannot move to the test position on the test stand 10 by itself or by pushing.

[0044] Figure 2 illustrates, in an illustrative and schematic manner, the test stand 100 according to the present invention for the drivetrain of a vehicle 20 and the vehicle 20 under test. As can be seen, the test stand 100 according to the present invention comprises two load motors 110 that can be directly mounted on the hub 21 (not shown in Figure 2) of the vehicle 20. This makes the test stand 100 according to the present invention substantially more compact and cost-effective than known test stands 10. In particular, it eliminates the need for complex alignment of the load unit 11 or load motors 110 relative to the vehicle 20. Furthermore, the vehicle 20 can be moved under its own power to the required test position using the test wheels 130. In addition, a particular advantage of the test stand 100 according to the present invention is that, due to its structure, it does not require a space-consuming frame 15.

[0045] Figure 3 illustrates, in an exemplary and schematic manner, the details of a possible embodiment of the test stand 100 according to the present invention. A load motor 110 configured as an electric motor 110 can be seen. The load motor 110 comprises a motor housing 111 and a motor shaft 112 configured as a hollow shaft 112. The electric motor 110 or load motor 110, according to this example, is a permanently excited synchronous torque motor 110 having a liquid-cooled motor shaft 112. According to this example, the motor shaft 112 configured as a hollow shaft 112 comprises a rotary union, not shown in Figure 3. Glycol can be introduced into the rotary union as a coolant. The glycol flows through the hollow shaft 112 through holes in the hollow shaft 112, also not shown, and cools the hollow shaft 112. The synchronous torque motor is configured as a synchronous motor and comprises, for example, 12 permanent pole pairs. This relatively large number of pole pairs gives the load motor 110 a relatively high torque, even when applied at relatively low current strengths. This embodiment further offers the advantage that the load motor 110 has a relatively large radial width compared to its axial length. This type of electric motor 110 is also known as a so-called "torque motor (Torque-Motoren)". According to this example, the inverter 117 is located directly on the motor housing 111. However, alternatively, the inverter 117 can be located spaced apart from the motor housing 111. Furthermore, a load sensor 120 configured as a torque sensor 120 and a mounting module 130 can be seen. In this case, the load sensor is located on the axial side 116 of the load motor 110 opposite the hub 21, i.e., the so-called b side of the load motor 110. The load motor 110, load sensor 120, and mounting module 130 together represent a possible embodiment of the test stand 100 according to the present invention. The automobile 20 can only be seen in part. For ease of viewing, only the hub 21, vibration damper 22, and wheel linkage mechanism 23 of the automobile 20 can be seen in Figure 2.

[0046] As can be seen, the additional shaft 113 is guided through the hollow shaft 112. The additional shaft 113 has a plate-shaped end component 113' at its end facing the hub 21 of the vehicle 20. Through the plate-shaped end component 113', the shaft 113, in this example, abuts flat against the hub 21 and is connected to the hub 21 in a non-rotatable manner via a flange connection. For this purpose, the mounting module 130 has a concentric opening 131. The hub 21 is accessible from the side facing the load motor 110 through the concentric opening 131. The shaft 113 is drive-coupled to a load sensor 120 at its end opposite to the hub 21. The load sensor 120 itself is also drive-coupled to the hollow shaft 112. Thus, there is a drive-coupled connection from the motor shaft 112 to the hub 21 via the load sensor 120 and the additional shaft 113. Since the hub 21 is an end member of the drivetrain of the automobile 20, there is also a drive connection to the drivetrain of the automobile 20. As a result, the drivetrain can be tested under load. A load sensor 120 is drivably positioned between the hollow shaft 112 and the shaft 113, so that the load sensor 120 can detect the load transmitted from the load motor 110 to the hub 21, or the torque transmitted to the hub 21. Furthermore, to compensate for angular and radial offsets, a compensating coupling 121 is drivably provided between the load sensor 120 and the hollow shaft 112. The load motor 110 is further connected to the mounting module 130 in a non-rotatable manner via a flange connection on its axial side 115 facing the hub 21, which in this example is the so-called a side of the load motor 110.

[0047] In this case, the load motor 110 is non-rotatably connected to the radial outer portion 135 of the mounting module 130. The radial inner portion 136 is rotatably held by the outer portion 135. The inner portion 136 has a concentric opening 131. With this configuration, the mounting module 130 is held to the hub 21 only indirectly via the load motor 110. During the test operation, the load motor 110 is supported via the outer portion 135 of the mounting module 130 so that a load can be introduced to the hub 21. A pneumatic tire 138 is also placed on the mounting module 130. In this example, the pneumatic tire 138 is also approved for road operation of the automobile 20. The automobile 20 stands on the pneumatic tire 138 during the test process. This results in test behavior of the automobile 20's drivetrain that is always very close to reality.

[0048] Figure 4 illustrates, in an illustrative and schematic manner, a further possible embodiment of the test stand 100 according to the present invention. In this case, the test stand 100 of Figure 4 differs from the test stand 100 of Figure 3 in the configuration of the mounting module 130. In this example, a rubber coating 139 is placed on the mounting module 130 instead of a pneumatic tire 138. The rubber coating 139 similarly makes it possible to support the mounting module 130 on the base in a relatively realistic manner. However, in this case, in contrast to the pneumatic tire 138, it is not necessary to separately select an appropriate pneumatic tire 138 each time and attach it to the mounting module 130. Instead, the rubber coating 139 can be firmly and permanently placed on the mounting module 130.

[0049] Figure 5 illustrates, in an exemplary and schematic manner, yet another possible embodiment of the test stand 100 according to the present invention. The test stand 100 of Figure 5 differs from the test stand 100 of Figure 4 in only the configuration of the mounting module 130. According to this example, the mounting module 130 does not have a radially inner portion 136 which would be held in a rotatable manner by a radially outer portion 135. Instead, the mounting module 130 of Figure 5 has only one concentric opening 131. Furthermore, in the test stand 100 of Figure 5, two axially spaced bearings 137 are positioned radially between the hollow shaft 112 and the shaft 113 to receive lateral and axial forces. This allows the lateral force generated by the gravity of the load motor to be supported without acting on the load sensor 120. This improves the measurement accuracy of the load sensor 120.

[0050] Figure 6 illustrates, in an exemplary and schematic manner, yet further possible embodiment of the test stand 100 according to the present invention. In this case, the test stand 100 of Figure 6 differs from the test stand 100 of Figure 3 in the configuration of the mounting module 130. According to the embodiment of Figure 6, the mounting module 130 comprises a radially outer portion 135 and a radially inner portion 136. The inner portion 136 is held via a shaft 113 and a load motor 110. However, the mounting module 130 does not have a concentric opening 131. Instead, the inner portion 136 of the mounting module 130 is non-rotatably connected to the hub 21 on one side and non-rotatably connected to the shaft 113 on the other side. In addition, the mounting module 130 comprises a block device 132. The block device 132 allows the inner portion 136 to rotate relative to the outer portion 135 with the load motor 110 attached, by displacing the outer portion 135 in the direction of the load motor 110, thereby preventing it from being located in a plane common to the inner portion 136, and consequently preventing the block device 132 from exerting a blocking effect between the inner portion 136 and the outer portion 135. The block device 132 blocks rotation only when the inner portion 136 and the outer portion 135 are in a single plane together with the block device. This provides the advantage that the automobile 20 can move under its own power and, correspondingly, can be easily positioned and aligned for testing.

[0051] Figure 7 illustrates, in an illustrative and schematic manner, a possible embodiment of the mounting module 130 according to the present invention for a test stand 100. The mounting module 130 in Figure 7 differs from the mounting module 130 in Figure 6 in the following respects: the load motor 110 (not shown in Figure 7) is not mounted on the shaft 113, so the blocked block device 132 can be seen. The inner portion 136 cannot be rotated relative to the outer portion 135, so in this state the automobile 20 can move under its own power.

[0052] Figure 8 illustrates, in an exemplary and schematic manner, yet another possible embodiment of the test stand 100 according to the present invention. The test stand 100 of Figure 8 differs from the test stand 100 of Figure 6 in the following respects: on the one hand, the presence of a motor support 118 that engages with the motor housing 111 from above and receives the inclination moment of the load motor 110, which otherwise must be supported in the mounting module 130. In this example, the motor support 118 is a wire cable 118 mounted in a suitable structure on the test stand 100. In this example, the motor support 118 further includes a compensation element 119. The compensation element 119 includes a spring to which a pre-tension can be applied, and through the set pre-tension of the spring, it precisely supports the inclination moment of the load motor 110. On the other hand, the test stand 110 of Figure 8 also differs from the test stand 100 of Figure 6 in the presence of a support plunger 133 that is adjustable in three spatial directions and rotatable around three axes (each represented by an arrow). The mounting module 130 can be supported on the support plunger 133 during the test process. During the test process, by correspondingly operating the support plunger 133, for example, the uneven base during the driving of the automobile 20 is simulated. Similarly, almost all other possible base effects are simulated, particularly in relation to the steering motion of the steerable wheels of the automobile 20. [Explanation of Symbols]

[0053] 10 Test benches 11 Load Units 12 Connecting shaft 13 Drive motor 14 Terminal Box 15 frames 16 Support elements 20 Automobiles 21 Hubs 22 Vibration damper 23 Wheel linkage mechanism 100 test benches 110 Load motors, electric motors, permanently excited synchronous motors 111 Motor Housing 112 Motor shaft, hollow shaft 113 axis 113' Plate-shaped end piece 115 Axial side facing the hub 116 The axial side opposite the hub 117 Inverter 118 Motor support section, wire cable 119 Compensation elements 120 Load sensors, torque sensors 121 Coupling 130 Mounting Modules 131 Concentric openings 132 Blocking device 133 Support plunger 135 Radial outer portion 136 Inner portion in the radial direction 137 Bearing 138 pneumatic tires 139 Rubber coating

Claims

1. A test stand (100) for the drivetrain of an automobile (20), comprising at least one load motor (110) having a motor housing (111) and a motor shaft (112), at least one load sensor (120), and at least one mounting module (130), wherein the motor shaft (112) is configured to be driven-coupled to a hub (21) of the automobile (20), and the load sensor (120) is connected to the motor shaft (112) It is configured to capture the load transmitted to the hub (21), A test stand (100) characterized in that the axial side (115) of the motor housing (111) facing the hub (21) and the at least one mounting module (130) are configured to be connected to each other in a non-rotatable manner, the motor shaft (112) is configured as a hollow shaft (112), and the shaft (113) guided through the hollow shaft (112) is configured to be connected directly or indirectly to the hub (21) in a non-rotatable manner, the load sensor (120) is located on the axial side (116) of the motor housing (111) opposite to the hub (21), and the hollow shaft (112) is drivable to the shaft (113) via the load sensor (120).

2. The test stand (100) described in claim 1, A test stand (100) characterized in that at least one mounting module (130) has a concentric opening (131), and the hub (21) is accessible from the side facing the at least one load motor (110) through the concentric opening (131).

3. A test stand (100) according to claim 1, The at least one mounting module (130) comprises a radially outer portion (135) and a radially inner portion (136), The inner portion (136) is held in a rotatable manner by the outer portion (135), The inner portion (136) is configured to be connected to the hub (21) of the automobile (20) in a non-rotatable manner. The test stand (100) is characterized in that the outer portion (135) is configured to be connected in a non-rotatable manner to the axial side (115) of the motor housing (111) that faces the hub (21).

4. A test stand (100) according to claim 3, The test stand (100) is characterized in that the shaft (113) can be connected to the inner portion (136) in a non-rotatable manner.

5. A test stand (100) according to claim 4, The test stand (100) is characterized in that the shaft (113) is a component of the inner portion (136) of the at least one mounting module (130).

6. A test stand (100) according to any one of claims 3 to 5, A test stand (100) characterized in that it is possible to block the rotation of the inner portion (136) relative to the outer portion (135).

7. A test stand (100) according to any one of claims 1 to 6, A test stand (100) characterized in that a pneumatic tire (138) is placed on at least one mounting module (130).

8. A test stand (100) according to any one of claims 1 to 6, A test stand (100) characterized in that a rubber coating (139) is placed on at least one mounting module (130).

9. A test stand (100) according to any one of claims 1 to 8, A test stand (100) characterized in that at least one mounting module can be connected to a base by friction or geometry.

10. A test stand (100) according to any one of claims 1 to 9, A test stand (100) characterized in that at least one load motor (110) is configured as a permanently excited synchronous motor (110).

11. A test stand (100) according to any one of claims 1 to 10, The hollow shaft is equipped with a rotary union for introducing a coolant, and is also equipped with a flow path for the coolant to flow through the hollow shaft, characterized in that of a test stand (100).

12. A test stand (100) according to any one of claims 1 to 11, A test stand (100) characterized in that at least two axially spaced bearings (137) are arranged between the hollow shaft (112) and the shaft (113) in the radial direction for receiving axial and / or lateral forces.

13. A test stand (100) according to any one of claims 1 to 11, A test stand (100) characterized in that at least one load sensor (120) is configured as a torque sensor and / or force sensor.

14. A test stand (100) according to any one of claims 1 to 12, The test stand (100) is further characterized by comprising at least one motor support portion (118) configured to support the inclination moment of at least one load motor (110).

15. A test stand (100) according to any one of claims 1 to 12, The test stand (100) further includes at least one support plunger (133), the support plunger (133) being adjustable in three spatial directions and / or rotatable about three axes, and the support plunger (133) being configured to support the aforementioned mounting module (130), or The test stand (100) further comprises at least one hexapod-type actuator device, the actuator device configured to adjust the hub in three spatial directions and / or rotate around three axes.

16. A test stand (100) according to any one of claims 1 to 15, The test stand (100) is characterized by including a load motor (110), a load sensor (120), and a mounting module (130) for each of the drivable wheels of the automobile (20).

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