MECHATRONIC CHASSIS DEVICE FOR A MOTOR VEHICLE

Abstract

Disclosed is a mechatronic chassis device (6) for a motor vehicle comprises a housing (7) and at least one functional element (11) in the housing (7). The device is characterized by means (14) for recognizing the ingress of a liquid medium into the housing (7).

Claims

1. A mechatronic chassis device (6) for a motor vehicle, comprising: a housing (7); at least one functional element (11) in the housing (7); and means (14) for recognizing the ingress of a liquid medium (23) into the housing (7).

2. The mechatronic chassis device according to claim 1, wherein the means for recognizing the ingress of the liquid medium (23) comprise a sensor arrangement (14), which can be operated to monitor a filling level of the housing (7) with an electrically conductive medium (22).

3. The mechatronic chassis device according claim 1, comprising a monitoring means (14) having one or more measurement points (22a, 22b, 22c) extending in the housing (7), wherein the one or more measurement points is configured to determine an electrical conductivity.

4. The mechatronic chassis device according to claim 3, wherein each of the the one or more measurement points (22a, 22b, 22c) extends from a measurement point (21a, 21b, 21c, 21d, 21e, 21f, 21g, 21h) on the functional element (11) to the electrically conductive housing (7).

5. The mechatronic chassis device according to claim 1, wherein the at least one functional element present in the housing (7) comprises a printed circuit board (11) configured for controlling and/or supplying energy to a further functional element present in the housing (7) or for signal processing.

6. The mechatronic chassis device according to claim 1, wherein the functional element (11) is divided into at least two areas (15, 16) electrically separated from one another.

7. The mechatronic chassis device according to claim 1, wherein the functional element (11) comprises an edge section on which is arranged at least one of the one or more measurement points (21a, 21b, 21c, 21d, 21e, 21f, 21g, 21h) in a spaced-apart arrangement.

8. The mechatronic chassis device according to claim 1, wherein the housing (7) has a cylindrical shape that extends along a rotation axis (5).

9. The mechatronic chassis device according to claim 1, wherein the functional element (11) is in the form of an essentially flat body fitted essentially perpendicularly to the rotation axis (5) of the housing (7).

10. The mechatronic chassis device according to claim 1, wherein each of the one or more measurement points (21a, 21b, 21c, 21d, 21e, 21f, 21g, 21h) is connected to an electrical voltage source with the interposition of a first series resistor (19), and the housing (7) is connected to the ground potential of the electrical voltage source, with the interposition of a second series resistor (20).

11. The mechatronic chassis device according to claim 1, further comprising a control unit configured to monitor the one or more measurement points (22a, 22b, 22c) for the electrical conductivity by monitoring the electric voltage between individual points of the one or more measurement points (21a, 21b, 21c, 21d, 21e, 21f, 21g, 21h) and the housing (7).

12. The mechatronic chassis device according to claim 1, further comprising a control unit (18) operable to attribute a voltage drop at individual points of the one or more measurement points to below a specifiable threshold value to the event that a medium ingress into the housing (7) has taken place, and to trigger a compensating reaction.

13. The mechatronic chassis device according to claim 1, wherein the one or more measurement points (21a, 21b, 21c, 21d, 21e, 21f, 21g, 21h) are arranged that in the event of medium ingress, if a critical filling level of the housing (7) with the liquid medium (23) is reached, at least one of the one or more measurement points (21a, 21b, 21c, 21d, 21e, 21f, 21g, 21h) is immersed in the medium (23) and in that way an electrical connection between an immersed measurement point (21a, 21b, 21c, 21d, 21e, 21f, 21g, 21h) and the housing (7) is formed.

14. The mechatronic chassis device according to claim 1, wherein the one or more measurement points (21a, 21b, 21c, 21d, 21e, 21f, 21g, 21h) are distributed around a peripheral area of the housing (7), so that regardless of a rotational orientation of the housing (7) and/or a functional element relative to the rotation axis (5), at least one of the one or more measurement points (21a, 21b, 21c, 21d, 21e, 21f, 21g, 21h) will be in a lower area of the housing (7) and can therefore be used for the early recognition of medium ingress into the housing (7).

15. The mechatronic chassis device according to claim 1, wherein the mechatronic chassis device (6) comprises an actuator for one or more of an adjustable roll stabilizer (1), a steering device, a brake device, and/or a sensor.

16. The mechatronic chassis device according to claim 15, comprising an electric motor (8) and a transmission (9) arranged in the housing (7) in addition to the functional element (11).

17. An adjustable roll stabilizer (1) for a motor vehicle, comprising: two stabilizer sections (4a, 4b) configured to be coupled to wheel suspensions (3a, 3b) of associated wheels (2a, 2b) of the motor vehicle; and the mechatronic chassis device (6) according to, claim 15 with which the stabilizer sections (4a, 4b) can be rotated relative to one another about a rotation axis (5) in order to influence a rolling behavior of the motor vehicle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Below, the invention is explained in greater detail with reference to the attached drawing. From this, further advantageous effects of the invention emerge. The drawings show:

[0031] FIG. 1: A schematic view of an adjustable roll stabilizer,

[0032] FIG. 2: A mechatronic chassis device in the form of an actuator for an adjustable roll stabilizer, represented schematically in section,

[0033] FIG. 3: A sensor arrangement for a mechatronic chassis device as described with reference to FIG. 2, viewed schematically,

[0034] FIG. 4: The sensor arrangement as in FIG. 3, after a medium has entered,

[0035] FIG. 5: The sensor arrangement as in FIG. 3, indicating an area particularly at risk from the ingress of a medium,

[0036] FIG. 6: A schematic representation of a further example of a circuit arrangement.

DETAILED DESCRIPTION

[0037] First, to make clear the preferred field of application of the invention, FIG. 1 shows a simplified schematic view of an adjustable roll stabilizer 1. The adjustable roll stabilizer 1 is part of a chassis (not shown completely), of a motor vehicle (not shown). A wheel 2a on the left and a wheel 2b on the opposite side of the vehicle, on the right, are connected by respective wheel suspensions 3a on the left and 3b on the right to a body of the motor vehicle (not shown here for representational reasons). Each of the wheel suspensions 3a, 3b is coupled by respective coupling means in the form of a pendulum support (no more of which is shown here) to an end of an associated stabilizer section 4a on the left and a stabilizer section 4b on the right. The two stabilizer sections 4a, 4b are connected to one another in the middle of the vehicle by an actuator 6.

[0038] In a manner known as such, the adjustable roll stabilizer 1 is mounted to rotate about a rotation axis 5 relative to the vehicle body (mountings not shown). The actuator, here shown in simplified form as a cylindrical body, comprises a housing 7 in which, among other things, an electric motor and a multi-stage planetary transmission drivingly connected thereto are arranged. Via the motor-transmission unit the stabilizer sections 4a, 4b are in driving connection with one another. When the electric motor is at rest the two stabilizer sections 4a, 4b are connected solidly with one another by the actuator 6. By operating the electric motor, depending on the rotation direction of the electric motor the stabilizer sections 4a, 4b can be rotated relative to one another around the rotation axis 5. In that way, in a manner known as such the adjustable roll stabilizer 1 can be adjusted.

[0039] FIG. 2 shows a schematic, simplified sectioned view of an actuator 6, which can be used in an adjustable roll stabilizer 1 as explained with reference to FIG. 1. Accordingly, the housing 7 of the actuator 6 extends essentially as a cylindrical body along the rotation axis 5. The left-hand stabilizer section 4a is connected rotationally fixed to the housing 7 of the actuator 6. The right-hand stabilizer section 4b is connected to a drive element which is mounted by way of a roller bearing so that it can rotate relative to the housing 7 of the actuator 6, and which forms a drive output side of the motor-transmission unit in the housing 7. In a manner known as such the housing 7 contains an electric motor 8 which has a drive output shaft coaxial with the rotation axis 5. By these means the electric motor 8 drives an in this case three-stage planetary transmission 9, which on its output side is drivingly connected to the right-hand stabilizer section 4b. Correspondingly, by operating the electric motor 8 the multi-stage planetary transmission is driven, so that thereby the right-hand stabilizer section 4a can be rotated about the rotation axis 5 relative to the left-hand stabilizer section 4b (which is immobilized on the housing).

[0040] On a side of the electric motor 8 facing away from the planetary transmission 9 there is fixed to the housing 7 a bearing disk 10, among other things as a bearing for the motor shaft of the electric motor 8.

[0041] In the housing 7 of the actuator 6, besides the electric motor 8 and the multi-stage planetary transmission 9 there is a further important functional element in the form of a printed circuit board 11. The printed circuit board 11 is a board for holding electronic components, which in a general way serve for energy supply, for signal processing and for the control of the actuator 6. It should be pointed out expressly that its representation in FIG. 2 is purely schematic and in particular that it can also be positioned elsewhere inside the housing 7 and/or that it can have other dimensions or be otherwise designed.

[0042] In the example shown, a power module 13 is arranged on the printed circuit board 11 and the printed circuit board 11 is in contact with a heat sink 12, which during operation performs a passive cooling function in order to prevent overheating of electronic components. It is understood that the printed circuit board 11 is connected to at least one on-board electrical network of the associated motor vehicle in order to be supplied with a necessary system voltage, and that the printed circuit board 11 is electrically connected to the electric motor 8 and if necessary to other components such as sensors accommodated in the housing 7.

[0043] For the connection of the printed circuit board 11 to an on-board electrical network of the motor vehicle, and also for signal transmission to the motor vehicle, the housing 7 has to be connected thereto. Correspondingly, at least in one area (not indicated here) the housing 7 has an opening. Even when careful sealing of such an opening is attempted, over the lifetime of the actuator 6 it cannot be excluded that under the action of severe environmental influences such as spray-water, moisture in the form of water will make its way into the housing 7. Water can also find its way in, in the area of the rotary bearing of the right-hand stabilizer section 4b relative to the housing 7. Particularly having regard to the perfect functioning of electronic components inside the housing 7, especially the printed circuit board 11, it is desirable to recognize the ingress of a liquid medium into the housing 7 at an early stage. A possible solution for this is described with reference to FIGS. 3 to 5 shown below.

[0044] FIG. 3 shows a sensor arrangement 14 which, according to the invention, can be used with an actuator 6 as described with reference to FIG. 2 for enabling the ingress of a liquid medium into the housing 7 of the actuator 6 to be recognized in an advantageous manner. To assist explanation FIG. 3 shows, on the left, a schematic circuit diagram and on the right a schematic sectioned representation of the housing 7 of the actuator 6 with a printer circuit board 11 inside it, these two representations corresponding functionally with one another (since they relate to the same situation) and consequently being explained conjointly below.

[0045] On the right in the figure, which reproduces a section through the housing 7 of an actuator along the rotation axis 5, it can be seen that the housing 7 has, in projection along the rotation axis 5, a circular outer contour (corresponding to the cylindrical basic shape of the housing as explained in connection with FIG. 2). Inside the housing 7 there is a printed circuit board 11 which is essentially in the form of a flat body fitted in a position perpendicular to the rotation axis 5. Thus, the printed circuit board 11 extends essentially transversely to the rotation axis 5 and has a circular outer contour, at least in part. In the example embodiment shown the printed circuit board 11 is not in contact with the housing 7 at any point.

[0046] The printed circuit board 11 is divided into two electrically separated areas 15 and 16 by electrical separation means 25. One area corresponds to a first switching area 15 of the printed circuit board 11, which in turn is supplied from a first on-board network 26 of the motor vehicle. The other area corresponds to a second switching area 16, which in turn is supplied by a second on-board network 27 of the motor vehicle. Thus, the first switching area 15 and the second switching area 16 are operated at different voltage levels, which makes the electrical separation 25 on the printed circuit board 11 necessary in order to avoid a short-circuit between the two on-board networks.

[0047] The housing 7 of the actuator 6 consists of an electrically conductive material, a metal. As can be seen on the right in FIG. 3, along an edge section of the printed circuit board 11 extending peripherally close to the housing there are arranged in its second switching area 16 eight measurement points 21a, 21b, 21c, 21d, 21e, 21f, 21g and 21h a distance apart from one another. From each of these measurement points 21a to 21h there extends a measuring distance as far as the electrically conductive housing 7, by means of which a filling level of the housing with an electrically conductive medium can be monitored. For this, refer now to the left part of FIG. 3. This shows schematically a circuit with which the arrangement shown on the right of the figure can be used as a sensor arrangement. Represented schematically, a number of measurement points, of which as an example (abbreviated) only the measurement points 21a, 21b are indexed. From each of these measurement points 21a, 21b a measurement distance 22a, 22b (etc.) extends to the housing 7. The measurement points 21a, 21b (etc.) are connected via a high-resistance series resistor 19 to a voltage supply 17. On the other hand, the housing 7 is connected via a resistor 20 to the ground potential of the electric voltage supply 17. This also corresponds to the ground potential of the first on-board network 26 and the second on-board network 27.

[0048] A control unit 18 (microcontroller) measures the voltage existing at the measurement points 21a, 21b (etc.) and is therefore able to attribute a voltage drop at one of the measurement points to below a specifiable threshold value, to the event that a medium has succeeded in entering the housing 7, and if necessary, trigger a compensation reaction. This will be explained with reference to FIG. 4.

[0049] FIG. 4 shows the sensor arrangement whose structure has already been explained with reference to FIG. 3. Otherwise than shown in the FIG. 3 representation, a not inconsiderable amount of water has entered the housing 7 and has collected in a lower area of the housing 7, as indicated by the water-line 24. A measurement point 21c at the bottom of the figure in this installed position of the printed circuit board 11 is therefore immersed in the collected water below the water-line 24, which is an undesired situation. On the left of FIG. 4, this is illustrated simply by the ingress of medium 23 in the form of a water droplet. The result of the ingress of the medium 23 is that in this case the measurement distance 22c has a substantially higher electrical conductivity, which is detected directly by the control unit 18, leading to the conclusion that there has been an ingress of medium.

[0050] It is clear that the situation shown on the right in FIG. 4 is only an example. If the orientation of the housing 7 or the installed position of the printed circuit board 11 are different (in each case relative to the rotation direction around the rotation axis 5) it can happen that as a result of gravity the liquid medium collects near a different measurement point when the latter is in the lower part of the housing 7. Correspondingly, as explained with reference to FIGS. 3 and 4, the sensor arrangement 14 enables the ingress of a medium to be detected largely regardless of the orientation of the printed circuit plate.

[0051] As a supplement, FIG. 5 is intended to make clear that in the boundary area, i.e. in the area of the electrical separation 25 between the first and second switching areas 15, 16, monitoring for medium contact is particularly important. Since in the example embodiment shown the areas on the printed circuit board 11 in which, owing to limited space, contacts to two different on-board networks (first on-board network 26, second on-board network 27) are comparatively small, in this region monitoring for medium ingress (medium ingress 23 in the form of the water droplet indicated) plays a particularly important part since a bridging-over between the on-board networks can have harmful effects not only on the actuator 6 but also on the vehicle as a whole and its on-board networks and components connected thereto.

[0052] FIG. 6 shows a schematic representation of another example of a circuit arrangement, which can be used for a sensor arrangement 14 of a mechatronic chassis device as described earlier. This representation shows that the structure is basically the same as described for FIGS. 3 and 5. Accordingly components with the same function are given the same indexes and, to avoid repetitions, do not require further description. Thus, in what follows, specifically the features that are different will be discussed. These suggest a preferred implementation in a vehicle.

[0053] In FIG. 6 the printed circuit board 11 is indicated by a square. It is shown that features inside the square (indexes 15, 16, 17, 18, 19, 20) are structurally associated with the printed circuit board. An exception is the housing 7 which, to clarify its additionally perceived electrical function relating to the invention (namely as the ground conductor within the sensor arrangement), is also shown inside the square but which structurally surrounds the printed circuit board 11 (see FIGS. 2 to 5).

[0054] From FIG. 6 it can also be seen that the first switching area 15 of the printed circuit board 11 is associated with a first on-board network 26 and the second switching area 16 of the printed circuit board 11 is associated with a second on-board network 27. The first switching area 15 is operated at a first voltage 29 and the second switching area 16 is operated at a second voltage 30. The second voltage 30, for example, is many times higher than the first voltage 29. Correspondingly, on the printed circuit board 11 the switching areas 15 and 16 are electrically separated from one another by the electrical separation means 25, namely in order to avoid any cross-talk between the first switching area 15 and the second switching area 16.

[0055] The two onboard networks, the first one 26 and the second one 27, with which the switching areas 15 and 16 are respectively associated and which are supplied by them with voltage, are associated with the vehicle 28. In other words, the on-board networks 26 and 27 are vehicle-specific voltage supplies arranged in the structure of the vehicle containing the actuator 6. Correspondingly the vehicle has two on-board networks 26 and 27 with different voltage levels. As FIG. 6 makes clear, the ground potentials of the two on-board networks 26 and 27 on the vehicle (on the body side) are (electrically) connected with one another. Within the actuator 6, in particular on the printed circuit board 11, in contrast the grounds are separated. From the deliberately chosen electrical separation of the on-board networks on the printed circuit board 11, which however are connected on the body side (vehicle 28) there arises a particular need to avoid electrical cross-talk between the areas 15 and 16 during the operation of the actuator 6, particularly in order to prevent adverse effects on the vehicle-specific on-board networks. The invention contributes to this advantageously.

[0056] In an entirely general sense, the above-described voltage monitoring at the measurement distances 22a to 22h can take place during the ongoing operation of the actuator 6. Since the arrangement of the measurement points on the printed circuit board 11 constitutes a comparatively simple measure, in the manner described effective monitoring of the housing for the ingress of media can be realized by relatively simple means.

INDEXES

[0057] 1 Adjustable roll stabilizer [0058] 2a; 2b Left wheel: Right wheel [0059] 3a; 3b Left wheel suspension; Right wheel suspension [0060] 4a; 4b Left stabilizer section; Right stabilizer section [0061] 5 Rotation axis [0062] 6 Actuator [0063] 7 Housing [0064] 8 Electric motor [0065] 9 Multi-stage planetary transmission [0066] 11 Printed circuit board [0067] 12 Heat sink [0068] 13 Power module [0069] 14 Sensor arrangement [0070] 15 First switching area [0071] 16 Second switching area [0072] 17 Voltage supply [0073] 18 Control unit (microcontroller) [0074] 19 Resistor [0075] 20 Resistor [0076] 21a; 21b; . . . 21h Measurement point (a to h) [0077] 22a; 22b, 22c Measurement distance [0078] 23 Medium that has entered (electrically conductive, water) [0079] 24 Water-line [0080] 25 Electrical separation [0081] 26 First on-board network [0082] 27 Second on-board network [0083] 28 Vehicle (body side) [0084] 29 First voltage [0085] 30 Second voltage