Cooling device for electronic control unit

Abstract

The present disclosure relates to an electronic control unit for a motor vehicle, having a first electronic control device, in particular a first equipped circuit board. The electronic control unit additionally has a gas cooling duct for conducting a compressed gas. The gas cooling duct is connected in a thermally conductive fashion to the first electronic control device, and is designed to separate the compressed gas from the first electronic control device. The gas cooling duct has an expansion section in which a flow cross section of the gas cooling duct widens in order to expand and cool the compressed gas in order to cool the first electronic control device.

Claims

1. An electronic control unit for a motor vehicle, comprising: a first electronic control device; a gas cooling duct for conducting a compressed gas, wherein the gas cooling duct: is connected in a thermally conductive fashion to the first electronic control device, is designed to separate the compressed gas from the first electronic control device, and has an expansion section in which a flow cross section of the gas cooling duct widens in order to expand and cool the compressed gas in order to cool the first electronic control device; and a heat sink arranged in the gas cooling duct and connected in a thermally conductive fashion to the first electronic control device, wherein the heat sink has a multiplicity of cooling fins, wherein the multiplicity of cooling fins are oriented in a direction of flow in the gas cooling duct.

2. The electronic control unit according to claim 1, further comprising a second electronic control device, wherein the gas cooling duct is arranged between the first electronic control device and the second electronic control device.

3. The electronic control unit according to claim 2, further comprising a housing, wherein the first electronic control device, the second electronic control device or the gas cooling duct is arranged in the housing.

4. The electronic control unit according to claim 2, wherein the first electronic control device or the second electronic control device has a power component, that is a processor, a graphic processor, a network interface, a microcontroller and/or a memory unit, wherein the power component is connected in a thermally conductive fashion to the gas cooling duct.

5. The electronic control unit according to claim 4, wherein the power component is connected in a thermally conductive fashion to the expansion section or a section downstream of the expansion section.

6. The electronic control unit according to claim 2, wherein the gas cooling duct is fitted onto the first electronic device, or the second electronic control device is fitted onto the gas cooling duct.

7. The electronic control unit according to claim 2, wherein the heat sink is connected in a thermally conductive fashion to the second electronic control device.

8. The electronic control unit according to claim 7, wherein the heat sink is arranged in the expansion section or in a section downstream of the expansion section.

9. The electronic control unit according to claim 7, wherein the heat sink is connected in a thermally conductive fashion to a power component of the first electronic control device or of the second electronic control device.

10. The electronic control unit according to claim 2, wherein the heat sink includes a multiplicity of heat sinks, which are provided for the first electronic control device or for the second electronic control device.

11. The electronic control unit according to claim 10, wherein the multiplicity of heat sinks are provided for a multiplicity of power components of the first electronic control device or of the second electronic control device.

12. The electronic control unit according to claim 2, wherein the gas cooling duct is integrated into a cooling plate or cooling coil which is mounted together with the first electronic control device, the second electronic control device or a housing of the electronic control unit.

13. The electronic control unit according to claim 2, wherein the first electronic control device or the second electronic control device includes a printed circuit board, and wherein the printed circuit board is equipped with a power component on a side which faces the gas cooling duct.

14. The electronic control unit according to claim 1, wherein the gas cooling duct is designed to conduct a compressed air or is or can be connected to a pressure tank.

15. The electronic control unit according to claim 14, further comprising a temperature sensor for measuring a temperature of a power component of the first electronic control device, of a second electronic control device or of the electronic control unit, wherein a gas valve is controlled on the basis of a temperature which is measured by the temperature sensor.

16. The electronic control unit according to claim 14, wherein the pressure tank is a compressed air tank.

17. The electronic control unit according to claim 1, further comprising a gas valve which is arranged in the gas cooling duct for setting a flow rate of the compressed gas.

18. The electronic control unit according to claim 17, wherein the gas valve is arranged upstream of the expansion section or upstream of the gas cooling duct.

19. A motor vehicle comprising: a pressure tank; an electronic control unit including a first electronic control device; a gas cooling duct for conducting a compressed gas, wherein the gas cooling duct is: connected in a thermally conductive fashion to the first electronic control device, designed to separate the compressed gas from the first electronic control device, and has an expansion section in which a flow cross section of the gas cooling duct widens in order to expand and cool the compressed gas in order to cool the first electronic control device, wherein the gas cooling duct of the electronic control unit is connected to the pressure tank, and wherein the motor vehicle includes a motor and a compressor which is driven by the motor and is connected to the pressure tank; and a heat sink arranged in the gas cooling duct and connected in a thermally conductive fashion to the first electronic control device, wherein the heat sink has a multiplicity of cooling fins, wherein the multiplicity of cooling fins are oriented in a direction of flow in the gas cooling duct.

Description

BRIEF DESCRIPTION OF THE FIGURES

(1) Further details and advantages of the present disclosure are described below with reference to the appended drawings, in which:

(2) FIG. 1 shows an exemplary arrangement with a control unit;

(3) FIG. 2 shows a schematic sectional illustration through an exemplary control unit along the line B-B in FIG. 3;

(4) FIG. 3 shows another schematic sectional illustration through the exemplary control unit along the line A-A in FIG. 2; and

(5) FIG. 4 shows a sectional illustration according to FIG. 3 of a different exemplary control unit.

(6) The embodiments shown in the figures correspond at least partially, with the result that similar or identical parts are provided with the same reference symbols, and for the explanation thereof reference is also made to the description of the other embodiments or figures in order to avoid repetitions.

DETAILED DESCRIPTION

(7) FIG. 1 illustrates an arrangement 10. The arrangement 10 has a motor 12, a compressor 14, a pressure tank 16, a gas valve 18 and an electronic control unit 20. The arrangement 10 can be provided, for example, in a motor vehicle, in particular a utility vehicle, for example a truck or a bus.

(8) An embodiment in which compressed air is used as the compressed gas for cooling the control unit is given below. Other embodiments can use other compressed gases.

(9) The motor 12 drives the compressor 14 to compress ambient air. The motor 12 can be an electric motor or an internal combustion engine. The ambient air heats up during the compression. The compressed air is buffered in the pressure tank 16, for example at a pressure of 8 bar. The compressed air cools in the pressure tank 16. The compressed air in the pressure tank 16 can be used for various applications.

(10) The compressed air from the pressure tank 16 can be directed to the electronic control unit 20 via the gas valve 18. The electronic control unit 20 can actuate the gas valve 18 to open or close. In some embodiments, the gas valve 18 can be a controllable gas valve which can be adjusted in an infinitely variable fashion between an open position and a closed position. The gas valve 18 permits a flow rate of compressed air from the pressure tank 16 to the electronic control unit 20 to be set.

(11) The gas valve 18 can be arranged in a gas cooling duct of the electronic control unit 20, in particular upstream of an expansion section of the gas cooling duct, or upstream of the gas cooling duct.

(12) FIG. 2 shows a section through a gas cooling duct of the control unit 20 according to the line B-B in FIG. 3.

(13) The control unit 20 has a housing 22. A gas cooling duct 24 which is embodied as a compressed air duct is arranged in the housing 22. The gas cooling duct 24 is connected to the pressure tank 16 via the gas valve 18 (see FIG. 1). The gas cooling duct 24 extends between an inlet 26 on the housing 22 and an outlet 28 on the housing 22. When the gas valve 18 is opened (see FIG. 1), compressed air flows through the inlet 26 into the gas cooling duct 24, as characterized by an arrow X. The compressed air flows through an expansion section 24A of the gas cooling duct 24. Finally, the compressed air in the gas cooling duct is diverted through approximately 180, as illustrated by arrows Y. Finally, the compressed air exits the housing 22 through the outlet 28, as illustrated by arrows Z. The compressed air can be output into the surroundings from the outlet 28, for example. The inlet 26 and the outlet 28 are arranged on the same side of the housing 22. Of course, depending on the requirements it is also possible to use other ways of conducting the flow for the gas cooling duct.

(14) In the expansion section 24A, a flow cross-sectional area of the gas cooling duct 24 becomes larger. The pressure of the compressed air is reduced when it flows through the expansion section 24A. This brings about cooling of the expanding compressed air in the expansion section 24A. The cooling and cooled compressed air flows through a plurality of heat sinks 30, 32 and 34, which each have a multiplicity of cooling fins. The heat sink 30 projects partially into the expansion section 24A. The heat sinks 32 and 34 are arranged downstream of the expansion section 24A. The cooling fins of the heat sinks 32, 34 and 36 are oriented in a direction of flow in the gas cooling duct 24. When there is a flow through the cooling fins, the compressed air which is cooled by the expansion cools the cooling fins of the heat sinks 30, 32 and 34. The heat sinks 30, 32 and 34 are connected in a thermally conductive fashion to corresponding power components 36, 38 and 40.

(15) The power components 36, 38 and 40 are arranged outside the gas cooling duct 24. This is indicated in FIG. 2 by the contours of the power components 36, 38 and 40 which are illustrated only by dots. The power components 36, 38 and 40 can heat up during operation of the electronic control unit 20. The conduction away of heat from the power components 36, 38 and 40 takes place via the heat sinks 30, 32 and 34.

(16) The power components 36, 38 and 40 are, in particular those components of the electronic control unit 20 which can heat up during the operation of the electronic control unit 20 to such an extent that they require cooling. The power components 36, 38 and 40 can be embodied, for example, as a processor, graphic processor, microcontroller, network interface and/or memory unit.

(17) In some embodiments, a greater or smaller number of power components can be connected in a thermally conductive fashion to the gas cooling duct 24.

(18) FIG. 3 shows by way of example how the power components 36, 38 and 40 are connected in a thermally conductive fashion to the heat sinks 30, 32 and 34. In the illustrated embodiment, the gas cooling duct 24 is fitted with the expansion section 24A onto the power components 36, 38 and 40.

(19) An equipped circuit board 42 has a printed circuit board 44 and the power components 36, 38 and 40. The equipped circuit board 42 is arranged in such a way that the power components 36, 38 and 40 extend from the printed circuit board 44 in the direction of the gas cooling duct 24. In other words the printed circuit board 44 is equipped with the power components 36, 38 and 40 on a side which faces the gas cooling duct 24. Cooling of the heat sinks 30, 32 and 34 by means of the expanding compressed air therefore brings about cooling of the power components 36, 38 and 40.

(20) The gas cooling duct 24 separates the compressed air from the equipped circuit board 42. It is therefore possible to prevent the equipped circuit board 42 from entering into contact with impurities in the compressed air such as, for example, particles of dust or oil droplets.

(21) The power components 36, 38 and 40 are connected, in particular in a thermally conductive fashion, to the expansion section 24A or to a section of the gas cooling duct 24 downstream of the expansion section 24A. This permits the cooling performance by means of the expanding compressed air to be generated precisely where it is needed to cool the power components 36, 38 and 40.

(22) The air which is heated by the heat sinks 30, 32, 34 exits the electronic control unit, for example without increased pressure, through the outlet 28. It goes without saying that not only are the power components 36, 38 and 40 cooled but also the entire equipped circuit board 42, by the cooling gas cooling duct 24.

(23) The electronic control unit 20 can additionally have a temperature sensor 46. The temperature sensor 46 measures a temperature of the electronic control unit 20, in particular of the equipped circuit board 42 and/or of the power components 36, 38 and 40. On the basis of a temperature measurement by the temperature sensor 46, the electronic control unit 20 can control the gas valve 18 (see FIG. 1). For example, the electronic control unit 20 can control the gas valve 18 in such a way that a temperature between 20 C. and 40 C. as measured by the temperature sensor 46 remains. In particular, the gas valve 18 can be opened if the temperature of the electronic control unit 20 exceeds an upper threshold value. The gas valve 18 can be closed if the temperature of the electronic control unit 20 undershoots a lower threshold value. In some embodiments, a flow rate can additionally or alternatively be set by the gas valve 18 in a stepless fashion. It is also possible for a plurality of temperature sensors to be provided.

(24) The conduction of heat between the heat sinks 30, 32 and 34 and the power components 36, 38 and 40 can be improved further by using thermally conducive paste, thermally conductive foils and/or additional heat sinks. In addition, heat sinks can be used, in particular, to bridge a distance between the power components 36, 38 and 40 and the gas cooling duct 24. In this way, it is possible, for example, to compensate for different heights of the power components 36, 38 and 40.

(25) The selected cooling of the electronic control unit 20 permits the electronic control unit 20 to be operated in a cool operating range. Therefore, for example relatively high performance levels and a relatively long service life can be achieved. Furthermore, the proposed cooling system does not require any moving parts such as, for example, fans which can experience wear over time. In addition, the electronic control unit 20 can be embodied in a particularly compact way since no large surfaces are required for cooling by convection. If the electronic control unit 20 is arranged in a driver's cab of a motor vehicle, desired heating of the driver's cab can be reduced or prevented.

(26) FIG. 4 shows a further embodiment with two equipped circuit boards. In addition to the first equipped circuit board 42 as in the embodiment described previously, a second equipped circuit board 48 is provided. In particular, the gas cooling duct 24 is fitted onto the first equipped circuit board 42, and the second equipped circuit board 48 is fitted onto the gas cooling duct 24. The first equipped circuit board 42 and the second equipped circuit board 48 can be connected to one another.

(27) The second equipped circuit board 48 has a printed circuit board 50 and power components 52, 54 and 56. The power components 52, 54 and 56 extend from the printed circuit board 50 in the direction of the gas cooling duct 24. The power components 52, 54 and 56 are connected in a thermally conductive fashion to the heat sinks 30, 32 and 34.

(28) The illustrated sandwich design permits a particularly compact electronic control unit 22, since both an upper side and an underside of the gas cooling duct 24 are used for cooling.

(29) In other embodiments, instead of the equipped circuit board 42 and/or the equipped circuit board 48 another electronic control device can be provided which is cooled by the expanding compressed air.

(30) In some exemplary embodiments, the gas cooling duct 24 can be integrated into a cooling plate or cooling coil which is mounted together with the first electronic control device 42, the second electronic control device 48 (if present) and/or the housing 22 of the electronic control unit 20. It is therefore possible, for example, for a cooling plate or cooling coil to be fitted or mounted with the gas duct 24 directly onto the first electronic control device 42. The cooling plate or cooling coil can also be provided outside a housing of the first electronic control device 42.

(31) Specialists will recognize that the device disclosed here for cooling the electronic control unit 20 is based on an innovative method for cooling an electronic control unit 20. The method can use, for example, the arrangement 10, and is accordingly described by way of example below.

(32) The method for cooling the first and/or second equipped circuit boards 42, 48 comprises feeding a compressed gas, in particular compressed air, into the housing 22. In the housing 22 a defined expansion of the compressed gas takes place in the expansion section 24A. The expansion section 24A is connected in a thermally conductive fashion to the first and/or second equipped circuit boards 42, 48. The gas cools through the expansion. As a result, the first and/or the second equipped circuit boards 42, 48 are cooled.

(33) Before the feeding of the compressed gas, the gas can be compressed, for example, by the compressor 14 (see FIG. 1). In this context, a temperature of the gas can be increased. The compressed gas can cool in the pressure tank 16 before it is fed into the housing 22 of the electronic control unit 20.

(34) The present disclosure is not limited to the embodiments described above. In particular, a multiplicity of variants and refinements are possible which also make use of the concepts and therefore come under the scope of protection.

LIST OF REFERENCE SYMBOLS

(35) 10 Arrangement for cooling 12 Motor 14 Compressor 16 Pressure tank 18 Gas valve 20 Electronic control unit 22 Housing 24 Gas cooling duct 24A Expansion section 26 Inlet 28 Outlet 30 Heat sink 32 Heat sink 34 Heat sink 36 Power component 38 Power component 40 Power component 42 First equipped circuit board (first electronic control device) 44 Printed circuit board 46 Temperature sensor 48 Second equipped circuit board (second electronic control device) 50 Printed circuit board 52 Power component 54 Power component 56 Power component X, Y, Z Direction of air flow