Electronic control unit and electric power steering system

Abstract

The present invention relates to an electronic control unit (100) for an electric power steering system (200), the electric power steering system (200) including a housing (210) and an electric motor, the electronic control unit (100) being configured to be disposed inside the housing (210) and electrically connected to the electric motor, wherein the electronic control unit (100) includes at least one power board (30, 40) and a heat sink (50), the at least one power board (30, 40) being attached to the heat sink (50), and thereby the heat sink edge (59) of the heat sink (50) including a groove (51), the groove being arranged for pressing the housing (210) into the groove (51) and thereby securing the heat sink (50) to the housing (210). The invention further relates to an electric power steering system (200).

Description

Technical Field

[0001] This invention relates to an electronic control unit for an electric power steering system and an electric power steering system. Background Technology

[0002] In an electric power steering system, the electronic control unit can be connected to an electric motor to supply power to the electric motor from a source such as a battery. The electric power steering system can assist a driver or a machine in an autonomous vehicle in handling transport equipment (typically steering). The transport equipment can be a car.

[0003] The electric power steering system may further include a torque sensor, a steering shaft, a handle (typically a steering wheel), and a power source. The typical layout and operation of an electric power steering system in a car will be described below.

[0004] The torque sensor can be mounted on the steering shaft. When the steering shaft is rotated by operating the handle, the torque sensor detects the torque applied to the steering shaft by operating the handle. When the torque sensor detects the torque, a torque signal is output from the torque sensor to the electronic control unit. The electronic control unit then drives the electric motor based at least on the torque signal. Optionally, in addition to the torque signal for controlling the drive of the electric motor, the control device may include other data, such as vehicle speed.

[0005] The electronic control unit drives the electric motor by supplying drive current from a power source (such as the car's battery). Then, depending on the car's configuration, the driving force generated by the electric motor is transmitted to the wheels directly or via a gearbox. Therefore, the electric power steering system changes the wheel steering angle by amplifying the torque of the steering shaft using the electric motor. This allows the driver to operate the steering wheel with less force.

[0006] The electronic control unit includes a power board electrically connected to the electric motor. Power is transmitted to the electric motor via this power board. Consequently, the power board generates heat during operation of the electronic control unit. To prevent overheating and damage to the electronic control unit, a heat sink may be disposed inside the electronic control unit and arranged to be in thermal contact with the housing of the electric power steering system or electric motor.

[0007] DE 10 2007 014 645 A1 describes an electrical component for an electric power steering system in a motor vehicle. An electric motor is disposed within a tubular housing made of a thermally conductive material, and includes an electronic control unit for controlling the electric motor and a radiator connected to the housing for dissipating heat from the power components. The radiator is inserted into the tubular housing and has radial edges whose diameter corresponds in size to the inner diameter of the tubular housing.

[0008] In known configurations of heat sinks within the housing, heat generated by the power board inside the electronic control unit can be dissipated through the housing of the electric power steering system or the electric motor. However, it is desirable to further improve the heat dissipation characteristics of the electronic control unit while maintaining the low manufacturing cost of the electronic control unit and the electric power steering system. Summary of the Invention

[0009] Therefore, one object of the present invention is to improve the electronic control unit and electric power steering system known in the prior art for electric power steering systems, and in particular to provide an electronic control unit and electric power steering system for electric power steering systems with improved heat dissipation characteristics, which are also easy to assemble and have low manufacturing costs.

[0010] This problem is solved by the technical solution of the present invention. Therefore, this objective is achieved by the electronic control unit according to the present invention and the electric power steering system according to the present invention. Further details of the present invention are given in the specification and drawings. Thus, the features and details described in conjunction with the electronic control unit of the present invention apply to the electric power steering system, and vice versa, so that disclosures relating to various aspects of the present invention are mutually referenced or may be mutually referenced.

[0011] According to a first aspect of the invention, the problem is solved by an electronic control unit for an electric power steering system, the electric power steering system including a housing and an electric motor, the electronic control unit being configured to be disposed inside the housing and electrically connected to the electric motor, wherein the electronic control unit includes at least one power board and a heat sink, the at least one power board being attached to the heat sink, and wherein at least one peripheral outer surface of the heat sink edge of the heat sink is in direct contact with the inner surface of the housing, such that heat generated by the at least one power board is conducted to the housing via the heat sink.

[0012] The heat generated during the operation of the electronic control unit can be effectively transferred along the outer periphery of the heat sink edge to the inner surface of the housing. Therefore, heat is transferred from the interior of the electronic control unit, which generates heat, to the housing. The housing can have a surface area much larger than the heat sink itself. Therefore, the heat transferred to the heat sink can dissipate more quickly and easily at the housing. Furthermore, for example, the housing can be effectively cooled by ambient air.

[0013] Specifically, the outer diameter of the peripheral outer surface of the heat sink edge can be equal to or approximately equal to the inner diameter of the inner surface of the housing. This approximately includes deviations from a perfectly mathematically identical match due to technical reasons such as manufacturing precision. Therefore, the peripheral outer surface is in close contact with the housing so that heat generated in the at least one power board can be effectively transferred to the housing via the heat sink.

[0014] The electric motor may be specifically arranged inside the housing. The housing may specifically be an electric motor housing, i.e., the casing of the electric motor. The housing may specifically have a tubular shape. The housing may also specifically have a circular or elliptical cross-section. Similarly, the housing may be made of a thermally conductive material. The thermally conductive material may specifically be or include metals, such as aluminum, magnesium, copper, or similar materials.

[0015] The at least one power board can be mounted on the heat sink. The at least one power board can be surrounded by the edge of the heat sink. The at least one power board can be provided, in particular, as a printed circuit board. The at least one power board may include electronic components, such as coils and capacitors, for enabling the power board to transmit power from a power source to the electric motor.

[0016] The electronic control unit may further include a logic board. The logic board may, in particular, be provided as a printed circuit board. The logic board need not be attached to the heat sink. Specifically, the logic board may not be attached to the heat sink. During operation of the electronic control unit, the logic board generates less heat than the at least one power board; therefore, it is preferable to attach the at least one power board, which generates more heat during operation of the electronic control unit, to the heat sink.

[0017] Furthermore, the electronic control unit may further include a connector board. For example, the connector board may be made of plastic. The connector board may be formed as a cap for sealing the housing at one end of the housing. The connector board may be provided with a seal for sealing the interior of the housing relative to the outside. The seal may be made of silicone rubber. The connector board may include one, two, three, or more connectors, particularly plug connectors. Electrical contacts may be provided at or inside the plug connectors. The electrical contacts may be made of, for example, a copper alloy to provide high conductivity. One or more of the plug connectors may be configured to contact the control board of the transport device with the logic board. Thus, the torque sensor, other sensors, and / or other electronic control units can be connected to the logic board. These plug connectors can be connected to the at least one power board via a power connector.

[0018] Possibly, the radiator includes a slot arranged for pressing the housing into the slot and thereby securing the radiator to the housing.

[0019] When the housing is pressed into the slot of the radiator, a particularly tight fit of the radiator inside the housing is achieved, and thermal conductivity from the radiator to the housing is also improved. The slot, arranged to press the housing into the slot, can therefore also be configured to thermally connect the radiator to the housing. Furthermore, the total contact surface between the radiator and the housing is further improved, thereby improving the overall thermal conductivity from the radiator to the housing. Moreover, providing a radiator with the slot can be implemented at a relatively low cost when manufacturing the radiator, and pressing the housing into the slot is a relatively simple, quick, and cost-effective way to secure the radiator to the housing of the electric power steering system, particularly within the entire electronic control unit.

[0020] Press-fitting can be performed by pressing the housing into the groove at the outside of the housing. This plastically deforms the housing and brings it into contact with the radiator at the groove. The groove can have, for example, a rectangular, U-shaped, or V-shaped shape. Alternatively, more than one groove can be provided in the radiator to press it together with the housing. For example, the radiator edge can include at least two grooves for pressing the housing into the at least two grooves.

[0021] Possibly, the groove is a peripheral groove, such that it is arranged around at least half of the periphery of the radiator edge, preferably around the entire periphery of the radiator. This allows for particularly simple pressing around the radiator edge and the periphery of the housing, and enables a particularly secure connection between the radiator and the housing.

[0022] Furthermore, it is possible that the groove is arranged between two peripheral outer surfaces of the heat sink edge, thereby directly connecting the heat sink and the housing. Thus, the housing can be pressed into the groove between the two peripheral outer surfaces of the heat sink edge, such that the housing is pressed between the two peripheral outer surfaces. This provides a particularly robust connection between the heat sink and the housing. In particular, the outer diameter of the two peripheral outer surfaces of the heat sink edge can be equal to or approximately equal to the inner diameter of the inner surface of the housing. This approximately includes deviations from mathematical exact equality due to technical reasons such as manufacturing precision. Therefore, the two peripheral outer surfaces are in close contact with the housing, so that heat generated in the at least one power board can be effectively transferred to the housing via the heat sink.

[0023] Furthermore, it is possible that the press-fit housing thermally connects the heat sink to the housing at the groove. This can improve heat conduction from the heat sink to the housing.

[0024] Alternatively, the electronic control unit may include a first power board and a second power board as the at least one power board, with the heat sink sandwiched between the first and second power boards. The first and second power boards may each be configured as redundant power boards, independently supplying power to the electric motor. Both the first and second power boards may be arranged such that each has three-phase power to supply three-phase power to the electric motor. Therefore, the first and second power boards may be arranged together to supply six-phase power to the electric motor. The first power board may be disposed on one side of the heat sink, and the second power board may be disposed on the other side of the heat sink. The first and second power boards may be directly attached to the heat sink using their circuit boards and electronic components. A thermal interface material may be disposed between the first power board and the heat sink, and between the second power board and the heat sink, to thermally attach the corresponding components to each other for better thermal conductivity.

[0025] It is also possible that the electronic components of the first power board and the electronic components of the second power board face the heat sink. Further, it can be specified that the electronic components extend toward the heat sink. In particular, it can be specified that the electronic components extend at least partially inside the heat sink.

[0026] Furthermore, it is possible that the radiator is configured as at least a partially circular heat sink. Specifically, the radiator can be at least a semi-circular heat sink or a fully circular heat sink. The edges of the radiator may have or define the circular shape of the heat sink. The radiator can be a flat plate in the sense that its thickness is less than its diameter or radius.

[0027] Furthermore, the heat sink may include a plurality of thermally conductive surfaces arranged to contact electronic components of the at least one power board. A thermal interface material may be disposed between the electronic components and the thermally conductive surfaces. Thus, the heat generated by the electronic components can be conducted to the heat sink very efficiently.

[0028] Therefore, it is possible to arrange the plurality of thermally conductive surfaces at different heights along the thickness of the heat sink to accommodate electronic components of different heights. This allows for the maintenance of design freedom for the at least one power board in terms of its specific electronic components (such as their size and geometry), while still achieving high thermal conductivity from the at least one power board to the heat sink. In other words, the heat sink can be adapted in its form and geometry to the at least one power board, rather than the other way around.

[0029] Alternatively, the heat sink may include a heat sink through-hole, and at least one of the at least one power board may be bolted to the heat sink, the bolt passing through the heat sink through-hole and being fastened in a protrusion extending from the connector board of the electronic control unit. This allows for a simple, reliable, and detachable connection of the at least one power board to the heat sink and further to the connector board. Moreover, by arranging the logic board of the electronic control unit between the at least one power board and the connector board, the logic board of the electronic control unit can thereby be clamped and easily secured between the at least one power board and the connector board.

[0030] Alternatively or additionally, the heat sink may include heat sink holes, and at least one of the at least one power board may be secured to the heat sink by bolts fastened into the heat sink holes. This provides a simple, reliable, and detachable connection between the at least one power board and the heat sink.

[0031] Specifically, when a first power board and a second power board are provided in the at least one power board configuration, the first power board can be attached via the heatsink through-holes and the protrusions in the connector board, while the second power board can be attached via holes in the heatsink. This provides particularly good maintainability because the second power board can be replaced without removing the first power board from the heatsink, and further improves the reliability of the robust connection.

[0032] Furthermore, the heat sink may include a heat sink recess for a second power connector of the electronic control unit, the second power connector extending from the connector plate of the electronic control unit through the heat sink recess inside the heat sink to at least one of the at least one power board. These second power connectors can be used to transfer current from the connector plate that can be connected to the power supply to the at least one power board. The heat sink recess allows for a simple and cost-effective design of the heat sink and the second power connector. The heat sink recess can be designed as a flat slot. The second power connector can be designed as a second power cable or a second power connector. The second power connector can have a flat shape and / or a rectangular shape.

[0033] The term "second" in the context of the second power connector does not necessarily imply the presence of the first power connector as well. However, in a configuration with two power boards (a first power board and a second power board of the at least one power board), a first power connector can be provided for connection to the first power board. The second power connector is then connected to the second power board. Therefore, each of the two power boards can be individually supplied with current for transmitting that current as a drive current to the electric motor.

[0034] Alternatively, the heat sink may include a heat sink cutout extending specifically from the edge of the heat sink into the interior of the heat sink, and a second logic connector extending from the logic board of the electronic control unit through the heat sink cutout to at least one of the at least one power board. The heat sink cutout may have a partially circular shape and / or a partially flat shape. The heat sink cutout allows for a simple and cost-effective design for both the heat sink and the second logic connector.

[0035] The term "second" in the context of the second logic connector does not necessarily imply the presence of a first logic connector. However, in a configuration with two power boards (a first power board and a second power board of the at least one power board), a first logic connector can be provided for connecting the logic board to the first power board. The second logic connector can then be connected to the second power board. Therefore, each of the two power boards can be individually provided with signals or instructions from the logic board for transmitting drive current to the electric motor.

[0036] Therefore, it is possible that a first electric motor connector from one of the power boards extends through the radiator cutout for connection to the electric motor of the electric power steering system. Thus, the number of cutouts or recesses can be reduced, and the electronic control unit can have a compact design. Drive current from the power board in the at least one power board can be transmitted to the electric motor along the electronic control unit through the radiator via the first electric motor connector.

[0037] Similarly, the term "first" in the first electric motor connector does not necessarily imply the presence of a second electric motor connector. However, in a configuration with two power boards (a first power board and a second power board of the at least one power board), a second electric motor can be provided for connecting the second power board to the electric motor. The first electric motor connector can then be connected to the first power board. Thus, each of the two power boards can independently transmit drive current to the electric motor.

[0038] Furthermore, the radiator may include a radiator protrusion that extends beyond the at least one power board and is arranged to rest on the inner edge of the housing of the electric power steering system. With the aid of the radiator protrusion, the end position of the electronic control unit within the housing can be easily detected when the electronic control unit is installed in the housing. This end position is achieved when the protrusion is resting on the inner edge of the housing, and the electronic control unit cannot be further pushed into the housing without using excessive force to bend or damage the protrusion. This provides a defined position where the housing is pressed into the groove, and the pressing can be performed at this defined position whenever the radiator is engaged with the housing, thereby facilitating manufacturing.

[0039] According to a second aspect of the invention, an electric power steering system comprising an electronic control unit according to a first aspect of the invention solves the problem raised in the introduction of this specification, wherein the electric motor of the electric power steering system is electrically connected to the at least one power board by means of at least one electric motor connector, and thereby the housing of the electric power steering system is pressed into a slot of the heat sink of the electronic control unit.

[0040] In a configuration with two power boards (i.e., a first power board and a second power board of the at least one power board), the electric motor can be electrically connected to the first power board via a first electric motor connector and to the second power board via a second electric motor connector. Each of the power boards can supply three-phase current. Therefore, the electric motor can be designed as a six-phase electric motor. Thus, the electric motor can be driven independently by the drive current supplied by either or both of the two power boards. This provides a redundant and fault-resistant design for the electronic control unit and the electric power steering system.

[0041] When the radiator includes a protrusion extending beyond the at least one power board, the protrusion can be positioned on the inner edge of the housing of the electric power steering system. This achieves a defined position of the electronic control unit within the housing and a stable connection between the electronic control unit and the housing.

[0042] The electric power steering system may further include a torque sensor, a steering shaft, a handle (specifically a steering wheel), and a power source. The electric power steering system may further have an arrangement for operating the vehicle and can be arranged for operating the vehicle as described in the introductory section of this specification.

[0043] Further advantages, features, and details of the invention are described below, with reference to the accompanying drawings which illustrate embodiments of the invention in detail. Thus, features derived from the claims and features mentioned in the specification (whether considered individually or in any combination) may be essential to the invention. Attached Figure Description

[0044] The accompanying diagram shows:

[0045] Figure 1 An exploded view of the bottom perspective of an embodiment of an electronic control unit according to a first aspect of the present invention;

[0046] Figure 2 for Figure 1 An exploded view of the top-side perspective of the electronic control unit;

[0047] Figure 3 for Figure 1 and 2 Detailed side-view perspective diagrams of the two power boards and logic board of the electronic control unit;

[0048] Figure 4 A detailed illustration of a side perspective view of the assembled logic board and connector board;

[0049] Figure 5 A detailed illustration of a side perspective view of the assembled logic board, the connector board, and the assembled first power board;

[0050] Figure 6 for Figure 1 and 2 A detailed side-view perspective of the heat sink of the electronic control unit;

[0051] Figure 7 For assembly Figure 6 Radiator and Figure 5 A detailed side perspective view illustrating the process of assembling the logic board, the connector board, and the first power board together.

[0052] Figure 8 The logic board and the connector board assembled together, the first power board assembled together, and Figure 6 Detailed illustration of the side perspective view of the heat sink components;

[0053] Figure 9 for Figure 1 and 2 A side perspective view of the electronic control unit 100 in its assembled state;

[0054] Figure 10 For assembly Figure 9 A side perspective view illustrating the process of an embodiment of the electronic control unit and the electric power steering system of the present invention; and

[0055] Figure 11 For crossing Figure 10 A cross-sectional view of the electric power steering system in which the electronic control unit is internally assembled. Detailed Implementation

[0056] Figure 1 An exploded view of the bottom perspective of an electronic control unit 100 according to an embodiment of the present invention is shown. The bottom side of the components of the electronic control unit 100 is illustratively illustrated in this bottom perspective view.

[0057] Figure 2 Show Figure 1 The electronic control unit 100 is different in that Figure 2 From the top perspective view. According to this top perspective view, the top side of the components of the electronic control unit 100 is illustratively shown.

[0058] As from Figure 1 and 2 As can be seen, the electronic control unit 100 includes two power boards 30 and 40, namely a first power board 30 and a second power board 40. Power boards 30 and 40 can also be referred to as power stages. The two power boards 30 and 40 are arranged to supply power to the electric power steering system 200 (see...). Figure 10 and 11 The electric motor (not shown) is supplied with drive current. For this purpose, the first power board 30 is connected to a first electric motor connector 80 that can be electrically connected to the electric motor. Furthermore, for this purpose, the second power board 40 is connected to a second electric motor connector 90 that can be electrically connected to the electric motor.

[0059] Furthermore, the electronic control unit 100 includes a connector board 10. The connector board 10 includes a plurality of (three in this particular embodiment) plug connectors 11.1, 11.2, and 11.3. In this particular embodiment, the first plug connector 11.1 and the second plug connector 11.2 have internal electrical contacts (not shown). These electrical contacts may be made of, for example, a copper alloy to allow for good conductivity. These electrical contacts are arranged as a first signal connector 15.1 and a second signal connector 15.2. The signal connectors 15.1 and 15.2 extend from the plug connectors 11.1 and 11.2 on the top side of the connector board 10 to the bottom side of the connector board 10.

[0060] The electronic control unit 100 also includes a logic board 20. The logic board 20 is arranged to control two power boards 30 and 40, or in other words, to control the operation of the electronic control unit 100, or even further, to control the transmission of drive current to the electric motor. For this purpose, signal connectors 15.1 and 15.2 are connected to the logic board 20. Furthermore, the logic board 20 is connected to the first power board 30 via a first logic connector 70. Additionally, the logic board 20 is connected to the second power board 40 via a second logic connector 60.

[0061] A signal plug (not shown) can be attached to plug connectors 11.1 and 11.2 for supplying signals from sensors such as torque sensors or other units of another electronic control unit such as a transportation device (not shown) (e.g., an automobile) to logic board 20. Using these signals (e.g., torque detected by the torque sensor or the speed of the transportation device), logic board 20 can control the drive current via two power boards 30 and 40.

[0062] The connector board 10 further includes a third plug connector 11.3. This third plug connector 11.3 internally includes additional electrical contacts. These electrical contacts are configured as first power connectors 16.1, 16.2 and second power connectors 17.1, 17.2. The first power connectors 16.1, 16.2 are longer than the second power connectors 17.1, 17.2, so that they can be connected to their respective power boards 30, 40 at corresponding distances from the connector board 10. In this embodiment, the first power connectors 16.1, 16.2 and the second power connectors 17.1, 17.2 are configured as metal strips.

[0063] A power plug (not shown) can be connected to a third plug connector 11.3 to provide power to the first power connectors 16.1, 16.2 and the second power connectors 17.1, 17.2. The power plug can be attached to a power source, such as a battery (not shown) of a transport device. The power supply is arranged as a three-phase power supply. Connector board 10 can also be referred to as a power and logic connector board because it provides power connections and logic or signal processing connections to the corresponding boards 20, 30, 40 of the electronic control unit 100.

[0064] The first power connectors 16.1 and 16.2 are connected to the second power board 40, and the second power connectors 17.1 and 17.2 are connected to the first power board 30. Thus, the first power board 30 is supplied with three-phase current, and the second power board 40 is supplied with three-phase current. The electronic control unit 100 is thus configured with six phases, and the electric motor can be configured as a six-phase electric motor. When one of the two power boards 30 and 40 fails due to an error, the other power board can ensure the safe and reliable operation of the electric motor by transmitting drive current to the electric motor. Therefore, it prevents unintended loss of steering function due to an error in one of the power boards 30 and 40, and prevents accidents and injuries that may occur to the driver and passengers of the transport equipment.

[0065] As from Figure 1 and 2 As can be further seen, the heat sink 50 is arranged between the first power board 30 and the second power board 40. The heat sink 50 is thus sandwiched between the two power boards 30 and 40. In this embodiment, the heat sink 50 is made of die-cast aluminum. The heat sink 50 enables the dissipation of heat generated in the two power boards 30 and 40. For this purpose, the heat sink 50 is connected to the housing 210 of the electric power steering system 200, which will be explained in more detail later.

[0066] Furthermore, the connector plate 10 includes a vent opening 13 and a venting element (not shown) for closing the vent opening 13. When the electronic control unit 100 is inserted into the housing 210 (which will also be explained in more detail later), the venting element provides pressure compensation to the interior of the housing 210 from the environment. Further, the connector plate 10 includes a seal 12. In this particular embodiment, the seal 12 is made of silicone rubber. When the electronic control unit 100 is inserted into the housing 210, the seal 12 seals the electronic control unit 100 relative to the environment inside the housing 210.

[0067] Figure 3 The logic board 20, the first power board 30, and the second power board 40 are shown in more detail in an exploded view. The logic board 20 includes first electronic components 21, which are exemplarily named 21.1, 21.2, and 21.3. Further, the first power board 30 includes second electronic components 31, which are exemplarily named 31.1, 31.2, and 31.3. Additionally, the second power board 40 includes third electronic components 41, which are exemplarily named 31.1, 31.2, and 31.3.

[0068] The first electronic component 21 may be a coil, a capacitor, at least one computing unit (such as a processor), and other electronic components for enabling computational operations based on received signals and for enabling logical communication between the logic board 20 and the two power boards 30, 40. The second and third electronic components 31, 41 may be coils, capacitors, and other electronic components for enabling the respective power boards 30, 40 to transfer power from the power source to the electric motor, as will be explained further later.

[0069] The logic board 20, the first power board 30, and the second power board 40 are shown with their respective top and bottom sides, for example, they are arranged within the electronic control unit 100. Thus, the largest of the second electronic components 31.1, 31.2, and 31.3 on the bottom side of the first power board 30 is shown facing the largest of the third electronic components 41.1, 41.2, and 41.3 on the second power board 40. These large electronic components 31 and 41 generate a large amount of heat, and with this arrangement, the heat sink 50 can receive the second and third electronic components 31 and 41 to achieve good thermal conductivity, so as to effectively remove heat from the two power boards 30 and 40 via the heat sink 50 and the housing 210.

[0070] Furthermore, the first power board 30 includes first power board recesses 32.1 and 32.2 for guiding the second power connectors 16.1 and 16.2 through them. Additionally, the first power board 30 includes power board through holes 33.1, 33.2, and 33.3 for guiding bolts 1 through them to secure the heatsink 50 to the connector board 10. These features will be explained in more detail later.

[0071] Figure 4 The assembly of logic board 20 and connector board 10 is shown. A first signal connector 15.1 and a second signal connector 15.2 are connected to logic board 20. In particular, the first signal connector 15.1 and the second signal connector 15.2 include a plurality of pins attached to corresponding pin receiving holes in logic board 20.

[0072] The logic board 20 includes two logic connectors 60 and 70 connected thereto, which serve to enable communication and control of the two power boards 30 and 40 by the logic board 20. Therefore, each of the two logic connectors 60 and 70, i.e., the first logic connector 70 and the second logic connector 60, includes a plurality of electrical connector pins (unnamed). The electrical connector pins of the first logic connector 70 are relatively shorter than those of the second logic connector 60. This is because the first logic connector 70 connects the logic board 20 to the first power board 30, where the distance between the logic board 20 and the first power board 30 is relatively short in the assembled state of the electronic control unit 100. However, the distance between the logic board 20 and the second power board 40, connected by the second logic connector 60, is relatively long because the first power board 30 and the heat sink 50 are arranged between the logic board and the second power board, as in, for example... Figure 10 This can be seen in the assembled state of the electronic control unit 100.

[0073] Electrical connector pins are inserted into corresponding connector pin holes (not labeled) inside the logic board 20. Connector pin holes for the corresponding electrical connector pins are arranged at two opposite ends of the logic board 20. Thus, the first logic connector 70 and the second logic connector 60 are arranged at two opposite ends of the logic board 20. Further, the logic board 20 includes connection pin holes (not labeled) for corresponding first connection pins (not labeled) of the first logic connector 70 and for corresponding second connection pins (not labeled) of the second logic connector 60. The two logic connectors 60 and 70 are securely fastened to the logic board 20 by means of the connection pins.

[0074] Electrical connector pins are arranged in the logic connector housings 71 and 61 of the first logic connector 70 and the second logic connector 60. In this particular embodiment, the second logic connector housing 61 consists of two separate parts. This design is chosen due to the long extension of the electrical connector pins. The first part of the second logic connector housing 61 includes connection pins for corresponding connection pin holes of the logic board 20, and the second part of the second logic connector housing 61 includes connection pins for fixing to corresponding connection pin holes of the second power board 40. Furthermore, the first logic connector housing 71 includes connection pins for fixing to corresponding connection pin holes of the first power board 30.

[0075] As can be seen from the figure, the logic board 20 includes cutouts at its edges for protrusions 18.1, 18.2, and 18.3, which protrude from the connector board 10 toward the logic board 20 and extend beyond it. These protrusions 18.2 and 18.3 enable the heat sink 50 to be fastened to the connector board 10, thereby clamping the logic board 20 and the first power board 30 between the heat sink 50 and the connector board 10, as will be explained later. The protrusions 18.2 and 18.3 may have molded holes internally. The molded holes may have pre-drilled threads for bolts 1 or be threaded by self-tapping screws or screws 1.

[0076] The first power connectors 17.1 and 17.2 extend from the connector board 10 through a cutout (not marked) at the edge of the logic board 20 toward the first power board 30. Furthermore, the second power connectors 16.1 and 16.2 extend from the connector board 10 toward the second power board 40 close to the logic board 20 and the first power connectors 17.1 and 17.2.

[0077] Figure 5 The assembly of the first power board 30, logic board 20, and connector board 10 is shown.

[0078] The first electric motor connector 80 includes three first phase pins 82.1, 82.2, and 82.3 for electrical connection with the electric motor of the electric power steering system 200. The three first phase pins 82.1, 82.2, and 82.3 are received within a first electric motor connector housing 81. The first electric motor connector housing 81 includes connection pins (not labeled) for connection with corresponding connection pin holes (not labeled) in the first power board 30. Further, the three first phase pins 82.1, 82.2, and 82.3 include, at their ends opposite to the ends for connection with the corresponding electric motor pins (not shown) of the electric motor, a plurality of first power board connection pins (not shown) for electrical connection with the first power board 30.

[0079] The first logic connector 70 is connected to the first power board 30. Furthermore, the second power connectors 16.1 and 16.2 are guided through the first power board recesses 32.1 and 32.2 of the first power board 30.

[0080] The first electric motor connector 80 is arranged adjacent to the second logic connector 60 so that they can be aligned as follows: Figure 6 The heat sink cutout 53 shown in the heat sink 50 extends together. The first electronic component 31 of the first power board 30 extends toward the heat sink 50 to be disposed on the top side of the first power board 30.

[0081] Figure 6 The radiator 50 is shown in more detail from its underside. A radiator edge 59 surrounds the radiator 50. The radiator 50, particularly the radiator edge 59, includes a groove 51 for pressing the housing 210 of the electric power steering system 200 into the groove 51. Thus, the housing 210 is mechanically secured to the radiator 50 and ultimately to the electronic control unit 100. Furthermore, the radiator 50 is thermally connected to the housing 210 so that heat generated by the two power boards 30, 40 can be dissipated along the housing 210 via the radiator 50, which has a much larger surface area for dissipation. Additionally, the surface area of ​​the housing 210 can be thermally connected to the environment so that the housing 210 is cooled, or in other words, can exchange heat with the environment.

[0082] The groove 51 is a peripheral groove 51, arranged around the periphery of the heat sink edge 59. The heat sink edge 59 further includes two peripheral outer surfaces 58.1 and 58.2, and the peripheral groove 51 is disposed between the peripheral outer surfaces 58.1 and 58.2. The two peripheral outer surfaces 58.1 and 58.2 of the heat sink edge 59 are configured to contact the inner surface 211 of the housing 210, as shown from... Figure 7 As can be seen, the outer diameters of the peripheral outer surfaces 58.1 and 58.2 are equal to or approximately equal to the inner diameter of the inner surface 211 of the shell 210.

[0083] The following will refer to Figure 7 and 8 Further explanation of the structure of radiator 50, Figure 7 This illustrates the process of assembling the heat sink 50, logic board 20, and connector board 10 together with the first power board 30. Figure 8 Showing according to Figure 7 Components of the process. Figure 7 and Figure 8 The top side of the radiator 50 is shown, while Figure 6 The bottom side of the radiator 50 is shown.

[0084] The heat sink 50 is configured as a circular heat dissipation plate, wherein the heat sink 50 includes a heat sink cutout 53. The heat sink cutout 53 extends from the heat sink edge 59 into the interior of the heat sink 50. The second logic connector 60 and the first electric motor connector 80 extend through the heat sink cutout 53 in the assembled state where the heat sink 50 is attached to the first power board 30, as shown in Figure 9 It can be seen in the image.

[0085] Furthermore, the heat sink 50 includes a plurality of thermally conductive surfaces 52 on its bottom and top sides for attaching the thermally conductive surfaces 52 to the first power board 30 and the second power board 40, particularly the first electronic component 31 and the second electronic component 41, by means of a thermal interface material (not shown). Figure 6 and Figure 8 The thermally conductive surfaces 52.1 and 52.2 on the bottom side and the thermally conductive surface 52.3 on the top side are exemplarily labeled. Figure 8 In the assembled state, the first electronic component 31 of the first power board 30 is in direct contact with the thermally conductive surfaces 52.1 and 52.2 on the bottom side of the heat sink 50 via a thermal interface material. The thermally conductive surfaces 52.1 and 52.2 on the bottom side are arranged at different heights along the thickness of the heat sink 50, and thus can be adapted to or attached to first electronic components 31 of different sizes or heights. This can also be applied to the top side, so that the thermally conductive surface 52 on the top side of the heat sink 50 can be arranged at different heights along the thickness of the heat sink 50. Thus, the first electronic component 31 effectively transfers heat to the heat sink 50.

[0086] In addition, the radiator 50 includes radiator through holes 54.1, 54.2, and 54.3, as shown in... Figure 10 From the bottom side and in Figure 11 As can be seen from the top side, the first power board 30 is secured by bolts 1, which pass through the radiator through-hole 54 and are fastened in the protrusions 18.1 and 18.2 of the connector board 10. The bolts 1 further pass through the power board through-holes 33.1, 33.2, and 33.3 of the first power board 30, as shown in the figure.

[0087] Furthermore, the heat sink 50 includes a heat sink recess 55 for guiding the second power connectors 16.1, 16.2 of the connector board 10 through it. This allows the second power connectors 16.1, 16.2 to be connected to the second power board 40 when the heat sink 50 is attached to the first power board 30.

[0088] Furthermore, the heat sink 50 includes heat sink protrusions 57.1, 57.2, and 57.3, which, in the assembled state of the electronic control unit 100, protrude from the heat sink 50 beyond the two power boards 30 and 40, as shown in... Figure 10As can be seen in the image. These radiator protrusions 57.1, 57.2, and 57.2 can be arranged to be placed on the inner edge 212 inside the housing 210 of the electric power steering system 200.

[0089] The heat sink 50 also includes heat sink holes 56.1, 56.2, and 56.3 on its top side. The second power board 40 can be fastened to the heat sink 50 by means of bolts 1 in the heat sink holes 56.1, 56.2, and 56.3. The heat sink holes 56.1, 56.2, and 56.3 may have pre-drilled threads or be threaded by self-tapping screws or screws 1.

[0090] Figure 9 The electronic control unit 100 is shown in an assembled state. A second power board 40 is attached to a heat-conducting surface 52 on the top side of a heat sink 50 via a second electronic component 41 on its bottom side. A second electric motor connector 90 includes three second electrical phase pins 92.1, 92.2, and 92.3 arranged in a second electric motor connector housing 91. The second electric motor connector housing 91 includes additional connection pins for connection to a sixth connection pin hole in the second power board 40.

[0091] Furthermore, the three second electrical phase pins 92.1, 92.2, and 92.3 include, at their ends opposite to the ends for connecting to the corresponding electric motor pins (not shown) of the electric motor, a plurality of second power board connection pins for electrical connection to the second power board 40. Furthermore, the second electric motor connector housing 91 includes a second electric motor connector housing through-hole for guiding the bolt 1 through it to connect the second power board 40 to the heat sink holes 56.1 and 56.3 of the heat sink 50 via the second electric motor connector housing 91.

[0092] Another bolt 1 is guided through a corresponding through hole in the second power board 40 to connect to the heat sink holes 56.2 and 56.4 of the heat sink 50. Here, the second power board 40 is attached to the top side of the heat sink 50 via its bottom side. The second power board 40 also includes second power board recesses 42.1, 42.2, and 42.3 through which the first electrical phase pins 82.1, 82.2, and 82.3 of the first electric motor connector 80 are guided.

[0093] All bolts 1 are tightened to secure the second power board 40 to the heat sink 50, and the heat sink 50 to the connector board 10. The heat sink 50 is thus sandwiched between the first power board 30 and the second power board 40. The logic board 20 is sandwiched between the first power board 30 and the heat sink 50. Electrical phase pins 82.1, 82.2, 82.3, 92.1, 92.2, 92.3 extend out of the second power board 40 and specifically extend beyond the heat sink protrusions 57.1, 57.2, 57.3 so that they can be connected to the motor pins of the electric motor. After the electronic control unit 100 is inserted into the housing 210, a venting element can be inserted into the vent opening 13.

[0094] Figure 10 The process of inserting the electronic control unit 100 into the housing 210 of the electric power steering system 200 is shown. Radiator protrusions 57.1, 57.2, and 57.3 act as guides during this process.

[0095] Figure 11 A cross-section is shown through a portion of the electric power steering system 200 having a housing 210. The housing 210 is not yet pressed into the groove 51 of the radiator 50. However, the pressing operation is indicated by an arrow marking the direction of the force F during the pressing operation. As a result, the housing 210 plastically deforms and extends into the groove 51 of the radiator 50. The radiator 50 and the housing 210 thus become attached to each other and thermally coupled.

[0096] Furthermore, the peripheral outer surfaces 58.1 and 58.2 of the heat sink 50 are attached to the inner surface 211 of the housing 210 to achieve thermal coupling and enable the heat sink 50 to dissipate the heat generated by the two power boards 30 and 40 attached to the heat sink 50 into the environment through the housing 210. In addition, the heat sink protrusions 58.1, 58.2, and 58.3 can be arranged to be placed on the inner edge 212 inside the housing 210.

[0097] The housing 210 is further sealed by a peripheral seal 12 of the connector plate 10 of the electronic control unit 10 abutting against the inner surface 211 of the housing 210. The connector plate 10 is thus designed as a cap for the housing 210. Furthermore, as can be seen in this cross-section, the first electrical phase pins 82.1, 82.2, and 82.3 are electrically connected to the electric motor pins of the electric motor of the electric power steering system 200.

[0098] List of reference numerals

[0099] 10 Connector Board

[0100] 11. Plug Connector

[0101] 12 Seals

[0102] 13 Ventilation openings

[0103] 15 Signal Connectors

[0104] 16 Second Power Connector

[0105] 17 First Power Connector

[0106] 18. Raised section

[0107] 20 Logic Boards

[0108] 21 First Electronic Component

[0109] 30 First Power Board

[0110] 31 Second electronic component

[0111] 32 First power board recess

[0112] 33 Power board through-hole

[0113] 40 Second power board

[0114] 41 Third Electronic Component

[0115] 42 Second power board recess

[0116] 50 radiator

[0117] 51 slots

[0118] 52 Thermally conductive surface

[0119] 53 Radiator Cutout

[0120] 54 Radiator Through Holes

[0121] 55 Radiator recess

[0122] 56 Radiator Holes

[0123] 57. Radiator protrusion

[0124] 58. Surrounding outer surface

[0125] 59. Radiator edge

[0126] 60 Second Logic Connector

[0127] 61 Second Logic Connector Housing

[0128] 70 First Logic Connector

[0129] 71 First Logic Connector Housing

[0130] 80 First Electric Motor Connector

[0131] 81 First Electric Motor Connector Housing

[0132] 82 First phase pin

[0133] 90 Second Electric Motor Connector

[0134] 91 Second Electric Motor Connector Housing

[0135] 92 Second phase pin

[0136] 100 Electronic Control Unit

[0137] 200 Electric Power Steering System

[0138] 210 Housing

[0139] 211 Inner Surface

[0140] 212 Inner Edge

[0141] F force

Claims

1. An electronic control unit (100) for an electric power steering system (200), the electric power steering system (200) including a housing (210) and an electric motor, the electronic control unit (100) being configured to be disposed inside the housing (210) and electrically connected to the electric motor, wherein the electronic control unit (100) includes at least one power board (30, 40) and a heat sink (50), the at least one power board (30, 40) being attached to the heat sink (50), and wherein the heat sink (50) At least one peripheral outer surface (58.1, 58.2) of the heat sink edge (59) is in direct contact with the inner surface (211) of the housing (210) such that heat generated by the at least one power board (30, 40) is conducted to the housing (210) via the heat sink (50), and the heat sink (50) includes a groove (51) arranged for pressing the housing (210) into the groove (51) and thereby securing the heat sink (50) to the housing (210), characterized in that, The electronic control unit (100) includes a first power board (30) and a second power board (40) as at least one power board (30, 40), and a heat sink (50) is sandwiched between the first power board (30) and the second power board (40), wherein the electronic components (31) of the first power board (30) and the electronic components (41) of the second power board (40) face the heat sink (50), wherein the heat sink (50) includes a plurality of thermally conductive surfaces (52) arranged to contact the electronic components (31, 41) of the at least one power board (30, 40), and the plurality of thermally conductive surfaces (52) are arranged at different heights along the thickness of the heat sink (50) to accommodate electronic components (31, 41) of different heights.

2. The electronic control unit (100) according to claim 1, characterized in that, The slot (51) is a peripheral slot, such that the peripheral slot is arranged around at least half of the periphery of the heat sink edge (59) of the heat sink (50).

3. The electronic control unit (100) according to claim 1 or 2, characterized in that, The groove (51) is arranged between two peripheral outer surfaces (58.1, 58.2) of the edge (59) of the radiator, and the two peripheral outer surfaces directly contact the inner surface (211) of the housing (210).

4. The electronic control unit (100) according to claim 1 or 2, characterized in that, The housing (210) subjected to compression thermally connects the heat sink (50) to the housing (210) at the groove (51).

5. The electronic control unit (100) according to claim 1 or 2, characterized in that, The radiator (50) is configured as a heat sink that is at least partially circular.

6. The electronic control unit (100) according to claim 1 or 2, characterized in that, The radiator (50) includes a radiator through-hole (54), and at least one of the at least one power board (30, 40) is fixed to the radiator (50) by a bolt (1) passing through the radiator through-hole (54) and being fastened in a protrusion (18) extending from the connector plate (10) of the electronic control unit (100).

7. The electronic control unit (100) according to claim 1 or 2, characterized in that, The radiator (50) includes a radiator hole (56), and at least one of the at least one power board (40) is fixed to the radiator (50) by a bolt (1) fastened in the radiator hole (56).

8. The electronic control unit (100) according to claim 1 or 2, characterized in that, The heat sink (50) includes a heat sink recess (55) for a second power connector (16) for the electronic control unit (100), the second power connector (16) extending from the connector plate (10) of the electronic control unit (100) through the heat sink recess (55) inside the heat sink (50) to at least one of the at least one power board (40) (30, 40).

9. The electronic control unit (100) according to claim 1 or 2, characterized in that, The heat sink (50) includes a heat sink cutout (53), and a second logic connector (60) extends from the logic board (20) of the electronic control unit (100) through the heat sink cutout (53) to at least one of the at least one power board (40) of the at least one power board (30, 40).

10. The electronic control unit (100) according to claim 9, characterized in that, The radiator cut extends from the edge (59) of the radiator into the interior of the radiator (50).

11. The electronic control unit (100) according to claim 2, characterized in that, The peripheral grooves are arranged around the entire periphery of the radiator (50).

12. An electric power steering system (200), the electric power steering system comprising an electronic control unit (100) according to any one of claims 1 to 11, characterized in that, The electric motor of the electric power steering system (200) is electrically connected to the at least one power board (30, 40) by means of at least one electric motor connector (80, 90), and thereby the housing (210) of the electric power steering system (200) is pressed into the slot (51) of the heat sink (50) of the electronic control unit (100).

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