EMC-FILTER FOR SUPPRESSING NOISE SIGNALS

Abstract

The invention which relates to an EMC filter for the suppression of interference signals addresses the problem of specifying a solution with which reworking expenditures of an inverter board are reduced and, additionally, installation space restriction as well as reduction of development and production costs are attained. This problem is resolved thereby that in an EMC filter module at least one core of a choke with a winding is disposed on a first mounting board, that at least one of the capacitors is disposed on the first mounting board, that the first mounting board comprises at least two contact means and that the first mounting board of the EMC filter module is disposed with its contact means on a main board of an inverter and is electrically connected thereto.

Claims

1.-10. (canceled)

11. An EMC filter for suppressing interference signals, comprising at least one choke, at least one core and several capacitors, wherein in an EMC filter module at least one core of a choke with a winding is disposed on a first mounting board, that at least one of the capacitors is disposed on the first mounting board, that the first mounting board comprises at least two contact means and that the first mounting board of the EMC filter module is disposed with its contact means on a main board of an inverter and is electrically connected thereto.

12. An EMC filter according to claim 11, further comprising a second mounting board disposed in the EMC filter module and that the core is disposed between the first mounting board and the second mounting board.

13. An EMC filter according to claim 12, wherein the second mounting board is disposed parallel to the first mounting board.

14. An EMC filter according to claim 12, wherein between the first mounting board and the second mounting board a connection means is disposed and wherein the core of the choke is disposed between the first and the second mounting board and is disposed on the connection means.

15. An EMC filter according to claim 12, wherein on a surface of the first mounting board and/or on a surface of the second mounting board at least partially a copper layer is disposed forming conductor tracks.

16. An EMC filter according to claim 12, wherein on the copper layer of the first mounting board and/or of the second mounting board forming conductor tracks capacitors are disposed.

17. An EMC filter according to claim 11, wherein as contact means noses or lugs are disposed on the first and/or the second mounting board or solder lugs or contact plugs or clip contacts or threaded contacts.

18. An EMC filter according to claim 12, wherein between the first and the second mounting board a core of a common mode choke is disposed or two cores of two differential mode chokes.

19. An EMC filter according to claim 15, wherein at least between a copper layer forming conductor tracks of the first mounting board and a copper layer forming conductor tracks of the main board a solder connection is disposed establishing an electrical connection.

20. An EMC filter as in claim 11, wherein the first mounting board is disposed with its orientation perpendicular to the main board.

21. An EMC filter as in claim 13, wherein between the first mounting board and the second mounting board a connection means is disposed and wherein the core of the choke is disposed between the first and the second mounting board and is disposed on the connection means.

22. An EMC filter according to claim 13, wherein on a surface of the first mounting board and/or on a surface of the second mounting board at least partially a copper layer is disposed forming conductor tracks.

23. An EMC filter according to claim 14, wherein on a surface of the first mounting board and/or on a surface of the second mounting board at least partially a copper layer is disposed forming conductor tracks.

24. An EMC filter as in claim 12, wherein the first mounting board is disposed with its orientation perpendicular to the main board.

25. An EMC filter as in claim 13, wherein the first mounting board is disposed with its orientation perpendicular to the main board.

26. An EMC filter as in claim 14, wherein the first mounting board is disposed with its orientation perpendicular to the main board.

27. An EMC filter as in claim 15, wherein the first mounting board is disposed with its orientation perpendicular to the main board.

28. An EMC filter as in claim 16, wherein the first mounting board is disposed with its orientation perpendicular to the main board.

29. An EMC filter as in claim 17, wherein the first mounting board is disposed with its orientation perpendicular to the main board.

Description

[0042] Further details, characteristics and advantages of implementations of the invention are evident based on the subsequent description of embodiment examples with reference to the associated drawing. Therein depict:

[0043] FIG. 1: an exemplary circuit configuration of a passive EMC filter according to prior art using as an example an EMC filter circuit with common mode choke,

[0044] FIG. 2: a schematic diagram of a structural unit for actuating an inverter, comprised of a main board and an EMC filter module according to the invention, and

[0045] FIG. 3: a perspective representation of an exemplary embodiment of an EMC filter module according to the invention with two mounting boards and a common mode choke.

[0046] FIG. 1 shows an exemplary circuit configuration of a passive EMC filter 1 according to prior art that is connected to an inverter 2. The EMC filter circuit 1 implemented as a passive filter comprises an input 3, at which, for example, a voltage of 400 V can be applied and comprises chokes L.sub.1 4 and L.sub.2 5 in feed lines HV+ and HV which, in the case of a common mode choke, are realized through the windings L.sub.1 4 and L.sub.2 5 disposed on a common core.

[0047] While the first capacitance 6 denoted C.sub.1 is disposed between the lines HV+ and HV directly at the input of the passive EMC filter circuit 1 and before chokes L.sub.1 4 and L.sub.2 5, the second capacitance 7 denoted C.sub.2 is disposed after chokes L.sub.1 4 and L.sub.2 5 at the output of the EMC filter circuit 1 and consequently at the input of the inverter 2.

[0048] A third capacitance 8 denoted C.sub.3 is disposed between the line HV and ground potential. A fourth capacitance 9 denoted C.sub.4 is disposed between the line HV+ and ground potential.

[0049] As is conventional in prior art, it is provided that the inverter 2 generates the electrical control signals that are necessary for operating an electric motor, not shown, which, for example, drives a refrigerant compressor.

[0050] This known circuit configuration is also comprised in the EMC filter module 10 according to FIG. 2 and implemented according to the invention in module architecture. Alternatively, instead of a common core 11 or choke core of a common mode choke, two cores 11 of two differential mode chokes can be disposed.

[0051] FIG. 2 shows a schematic depiction of a structural unit for actuating an electric drive motor, not shown, by the inverter 2, which unit is comprised of a main board 12 for the inverter 2 and an EMC filter module 10 according to the invention. On the main board 12 the components of the inverter 2 are applied that are necessary, for example, for the control of the operating mode of a motor in an air-conditioning compressor. These components are not explicitly shown in FIG. 2.

[0052] The main board 12 can be implemented in the customary manner as a single- or multi-layer circuit board. In the example the main board 12 comprises several copper layers 13 with which the necessary electrical connections for the components of the inverter 2 are provided in the form of conductor tracks.

[0053] In contrast to the conventional prior art, the components required for the EMC filter 1 are not disposed on the main board 12 but rather on an EMC filter module 10 according to the invention.

[0054] The EMC filter module 10 comprises at least one first mounting board 14 which can be implemented, for example, as a single- or a multi-layer circuit board. On this first mounting board 14 a core 11, for example for a common mode choke, is disposed. On this core 11 the windings 16a of the first choke L.sub.1 4 and the windings 16b of the second choke L.sub.2 5 are disposed. In FIG. 2 this arrangement, comprised of a core 11 and a winding 16, is only depicted by example with a single winding 16 instead of both windings 16a and 16b. This representation does not limit the invention to this implementation.

[0055] The invention provides in addition that on the first mounting board 14 the capacitors C.sub.1 6 to C.sub.4 9 necessary for the EMC filter circuit 1 are disposed. Alternatively, also only a portion of these capacitors C.sub.1 6 to C.sub.4 9 can be required and/or be disposed on the first mounting board 14.

[0056] It is provided for the first mounting board 14 to comprise contact means 17 with which an electrical connection can be established to the conductor tracks 13 of the main board 12. In an implementation these contact means 17 can be implemented in the form of a nose or lug that project from the mounting board 14.

[0057] To receive or to apply electrical contact of the EMC filter module 10 in or to the main board 12, the latter is provided with corresponding notches into which the nose- or lug-shaped contact means 17 can be inserted. To establish an electrical connection between a conductor track 13 of the first mounting board 14 and a conductor track 13 of the main board 12, a solder connection 18 can be provided. In this way an electrically conductive as well as also mechanically stable connection is provided between the first mounting board 14 of the EMC filter module 10 and the main board 12.

[0058] The contact means 17 can alternatively be carried out by a person of skill in the art such that an electrically conductive connection between the first mounting board 14 and the main board 12 is established across solder lugs, contact plugs, clip contacts or threaded contacts. A mechanically stable connection can also be obtained in these cases. In all cases, alternatively, additional means for a sound and stable securement of the EMC filter module 10 on the main board 12 can be provided.

[0059] In an embodiment of the EMC filter module 10 it can be provided that two cores 11 are disposed on the first mounting board 14. This can be the case, for example, in an implementation of the EMC filter module 10 with two differential mode chokes L.sub.1 4 and L.sub.2 5.

[0060] In a further embodiment is provided to dispose, for example parallel to the first mounting board 14, a second mounting board 15. In this case the core 11 of a common mode choke, for example, is disposed between the mounting boards 14 and 15.

[0061] The second mounting board 15 also comprises contact means 17 with which it can be electrically wired and mechanically connected to the main board 12, as is already known from the above description regarding the first mounting board 14. On the second mounting board 15, furthermore, capacitors C.sub.1 6 to C.sub.4 9 of the EMC filter module 10 can also be disposed.

[0062] For the mechanical connection of the first and the second mounting board 14 and 15 with one another a connection means 19 is provided. This connection means 19, which is depicted in FIG. 2 by a dashed line, is, for example, implemented as a web or a plate of a non-conducting material such as a synthetic material. The connection means 19 can be secured with the first and the second mounting board 14 and 15, for example, by adhesion, threaded connection, pressing, clamping or welding (plastic welding) and in this manner mechanically stabilize the EMC filter module 10.

[0063] Apart from this task of mechanical stabilization and fixing of the first and the second mounting boards 14 and 15, the connection means 19 is provided for receiving and mechanically fixing the core 11 between the mounting boards 14 and 15. For this purpose the connection means 19 is implemented such that it, for example, can be inserted into the inner diameter of an annular core 11 under form closure and subsequently be fixedly connected with the first and the second mounting board 14 and 15.

[0064] A third task of the connection means 19 when using a common mode choke comprises isolating the two windings 16a and 16b applied on the common core 11. With this isolation an electrical short circuit between the two windings 16a and 16b is avoided and sparks are also prevented from jumping between the two windings 16a and 16b.

[0065] In the case in which the EMC filter module 10 is equipped with two cores 11 for two differential mode chokes, for each core 11 one connection means 19 is utilized in the above described manner. Such an embodiment is not depicted in the Figures.

[0066] FIG. 3 shows a perspective representation of an exemplary embodiment of the EMC filter module 10 according to the invention. The EMC filter module 10 is implemented with a first and a second mounting board 14 and 15, between which the core 11 of a common mode choke with a first winding 16a and a second winding 16b is disposed.

[0067] Between the two mounting boards 14 and 15 a connection means 19 is disposed which is adhered to mounting boards 14 and 15 and fixes the annular core 11. FIG. 3 also shows that on the surface of the first mounting board 14 a copper layer 13 is applied. Through suitable structuring of this copper layer 13 the electrical connections or conductor tracks, necessary for the electrical contacting of the components of the EMC filter module 10, can be generated. In this way, for example, the capacitors 6, 7, 8 or 9 can be disposed on such a surface of the first mounting board 14. In FIG. 3 is depicted by example the first capacitor 6 (C.sub.1) on the first mounting board 14, which in the circuit of FIG. 1 is disposed at the input side between the input terminals HV+ and HV. Further capacitors 7, 8 or 9 can be disposed on the copper layers 13 of the second mounting board 15.

[0068] The first mounting board 14 comprises two nose- or lug-shaped contact means 17a and 17b with which an electrical connection can be established with the main board 12, not shown. The main board 12 is provided with corresponding rectangular openings into which the contact means 17a and 17b can be inserted. An electrical connection is established by soldering the copper layer 13 of the first mounting board 14 to a corresponding copper layer 13 or a conductor track 13 of the main board 12.

[0069] The same applies to the contact means 17c and 17d that are disposed on the second mounting board 15. The contact means 17a and 17b correspond in FIG. 1 to the input-side terminal designations HV+ Input and HV Input of the EMC filter module 10. The contact means 17c and 17d correspond in FIG. 1 to the output-side terminal designations HV+ Output and HV Output of the EMC filter module 10.

LIST OF REFERENCE NUMBERS

[0070] 1 EMC filter (EMC filter circuit) [0071] 2 Inverter [0072] 3 Input (HV+/HV) [0073] 4 First choke L.sub.1, winding L.sub.1 [0074] 5 Second choke L.sub.2, winding L.sub.2 [0075] 6 First capacitor C.sub.1, first capacitance [0076] 7 Second capacitor C.sub.2, second capacitance [0077] 8 Third capacitor C.sub.3, third capacitance [0078] 9 Fourth capacitor C.sub.4, fourth capacitance [0079] 10 EMC filter module [0080] 11 Core, choke core [0081] 12 Main board of inverter [0082] 13 Copper layers, conductor track, conductive path [0083] 14 First mounting board [0084] 15 Second mounting board [0085] 16, 16a, 16b Winding [0086] 17, 17a, 17b, 17c, 17 d Contact means [0087] 18 Solder connection [0088] 19 Connection means