Device for Improving the Electromagnetic Compatibility of Electric/Electronic Devices, Device, and Assembly

Abstract

A device for improving the electromagnetic compatibility of electric/electronic devices includes an electrically conductive spring element that is configured to be arranged between a first electric/electronic device and a second device in a biased manner in order to produce an electric connection between the two devices. The spring element has at least one helical spring with at least two winding sections running in opposite directions. The first electric/electronic device in one embodiment is a controller, and the second device in one embodiment is a brake system or actuator.

Claims

1. A device for improving the electromagnetic compatibility of electrical/electronic units, comprising: an electrically conductive spring element configured to be arranged pre-stressed between a first electrical/electronic unit and a second unit in order to produce an electrical connection between the two units, the spring element including at least one helical spring with at least two winding sections that are oriented in different directions.

2. The device as claimed in claim 1, wherein the winding sections are configured in a coaxial manner with respect to one another in two helical springs.

3. The device as claimed in claim 2, wherein the helical springs are configured as one piece with one another.

4. The device as claimed in claim 2, wherein the helical springs are configured separately and are connected to one another in an electrically conductive manner.

5. The device as claimed in claim 2, wherein the helical springs are connected to one another in a material-bonded manner at least at one spring wire end.

6. The device as claimed in claim 1, wherein the winding sections are configured in an axial manner one behind the other in a helical spring.

7. An electrical/electronic unit, comprising: a printed circuit board that comprises multiple electrical/electronic components and tracks; and at least one device configured to improve the electromagnetic compatibility of the electrical/electronic unit, the device comprising an electrically conductive spring element that is configured to be arranged pre-stressed between the printed circuit board and a second unit, in order to produce an electrical connection between the printed circuit board and the second unit, wherein the spring element includes at least one helical spring with at least two winding sections that are oriented in different directions.

8. An assembly, comprising: a first electrical/electronic unit; a second unit; and at least one device configured to improve the electromagnetic compatibility at least of the first unit, the device comprising an electrically conductive spring element that is held in a pre-stressed manner between the first unit and the second unit, the spring element including at least one helical spring with at least two winding sections that are oriented in different directions.

9. The assembly as claimed in claim 8, wherein the first unit comprises a printed circuit board that comprises multiple electrical/electronic components and tracks, and wherein the at least one helical spring lies in an axial manner at one end against an electrical connection contact of the printed circuit board and at the other end against an electrically conductive contact element of the second unit.

10. The assembly as claimed in claim 9, wherein the electrically conductive contact element of the second unit is an electrically conductive housing or housing part of the second unit.

11. The device as claimed in claim 1, wherein the first electrical/electronic unit is configured as a control unit and the second unit is configured as a brake system or an actuator.

12. The electrical/electronic unit as claimed in claim 7, wherein the electrical/electronic unit is configured as a control unit of a motor vehicle.

13. The assembly as claimed in claim 8, wherein the second unit is configured as one of a brake system, an actuator, an electric motor, an electric pump, a transmission, or a hydraulic block.

Description

[0016] In the drawing:

[0017] FIG. 1 illustrates a simplified sectional view of an advantageous assembly,

[0018] FIGS. 2A to 2D illustrate multiple views of an advantageous device of the assembly, and

[0019] FIGS. 3A and 3B illustrate different views of an alternative embodiment of the device.

[0020] FIG. 1 illustrates a simplified sectional view of an advantageous assembly 1 having a control unit 2 as a first unit and a brake system 3 as a second unit. The brake system 3 comprises an electromagnetic actuator 4 that can be controlled by means of the control unit 2 and in particular is used so as to actuate a valve (not illustrated). For this purpose, the control unit 2 comprises for example an electronic power system 5 that is arranged at least in parts on a printed circuit board 6. The printed circuit board comprises multiple electrically conductive tracks of which at least one terminates in an electrical connection contact 7, for example in the form of a contacting contact surface, or comprises such an electrical connection contact.

[0021] A spring element 8 is supported in an axial manner on the connection contact 7, said spring element lies at the other end against a housing 9 of the actuator 4. The spring element 8 is configured in an electrically conductive manner and consequently produces an electrical connection between the housing 9 and the printed circuit board 5. In this case the spring element 8 is embodied as a helical spring device 10 that is held guided at the side in a housing section 11 of a housing 12 of the control unit 2 and/or of the hydraulic system 3 with the result that the spring element 8 is reliably prevented from buckling even in the case of a high axial load.

[0022] The spring element 8 forms an advantageous device 13 for improving the electromagnetic compatibility in particular of the control unit 2. For this purpose, the spring element 8 is advantageously embodied in such a manner that it renders possible for electromagnetic pulses to be advantageously discharged even in the case of a high-frequency application. For this purpose, the spring element 8 is advantageously embodied as described below.

[0023] FIGS. 2A to 2D illustrate in this regard multiple views of a first exemplary embodiment of the spring element 8. In accordance with this exemplary embodiment, the spring element 8 is formed by two helical springs 14, 15 that are arranged in a coaxial manner with respect to one another. In this case, the helical springs 14, 15 are wound in opposite directions. FIG. 2B illustrates in this case in a single view the inner-lying helical spring 15 and FIG. 2C illustrates the outer-lying helical spring 14. The helical springs are connected to one another at their winding ends for example by means of a weld site 16 in a material-bonded, electrical and mechanical manner. As a consequence, the equivalent electrical circuit diagram illustrated in FIG. 2D is produced. The two helical springs represent in each case inductance L1, L2 that are however oriented in opposite directions. The electrical reactance of the respective helical spring 14, 15 increases to X.sub.L=2.sub.Π f L as the pulse frequency increases. As a consequence, the extent to which the electromagnetic pulses are discharged reduces as the pulse frequency increases and an increased number of interference signals are unintentionally output via the metal components. By virtue of the fact that two helical springs 14, 15 are provided, the winding sections 17, 18 of which are embodied or wound in opposite directions, the reactance reduces without additional electronic components being required for this purpose because the induced currents flow in opposite directions. A current pulse induces in the windings in each case a voltage that in the advantageous embodiment of the device 13 is oriented in the opposite direction with the result that the resulting voltage is less than the individual voltage and also consequently the resulting impedance. In the theoretical ideal case of identical coils, the induction voltages of the inductances L1 and L2 increase in a reciprocal manner. Optionally more than two helical springs 14, 15 are arranged in a coaxial manner with respect to one another in order to increase the number of inductances that are oriented in opposite directions and as a consequence to improve the power of the device 13. A side effect of the automated production process is that the spring of the device 13 is less inclined or not inclined at all to become disoriented or hooked in. The coaxial arrangement of the helical springs 14, 15 necessitates different winding diameters, as a result of which different spaces through which a magnet field flows are produced with the result that the coils comprise different inductances. A resulting apparent resistance is therefore still present but it is less than that of an individual helical spring 14, 15.

[0024] In accordance with an alternative exemplary embodiment, as illustrated in FIGS. 3A and 3B, the winding sections 17, 18 that are oriented in different directions in a single helical spring 19 are realized. The winding sections 17, 18 are in this case embodied in an axial manner one behind another in the helical spring 19. This produces the equivalent circuit diagram illustrated in FIG. 3B in which the inductances L1 and L2 are connected in series.

[0025] In the case of the present exemplary embodiment, it is ensured as a result of the winding radii or winding diameters being identical that the inductances L1 and L2 are identical. However, it is not possible to provide full compensation as a result of the series connection.

[0026] It is preferred that at least one spring end of the spring element 8 is embodied so that it can be fixed on the printed circuit board 5 by means of a SMD soldering process. In accordance with a further exemplary embodiment (not illustrated here) the winding direction of the windings or winding sections advantageously changes more than only twice, with the result that the helical spring 19 comprises for example 3 winding sections that comprise different winding directions lying one behind the other.