Motor with separate heat sinks

Abstract

The present invention relates to an electric machine, in particular an electronic commutation machine. The machine has a housing and a control device accommodated in the housing. The control device is configured to control the machine to generate a rotating magnetic field. According to the present invention, the housing has a housing cup and a housing cover surrounding a hollow space. The machine has a bearing cover accommodated in the housing cup, wherein the bearing cover is heat-conductingly connected to the housing cup. The machine also has a cooling plate, which is heat-conductingly connected to the housing cup and at least one component or multiple components of a control unit. The machine has a converter, which includes a semiconductor switch, wherein the semiconductor switch is heat-conductingly connected to the bearing cover. The bearing cover and the cooling plate surround a portion of the hollow space between each other, wherein a control unit and a converter are accommodated in a portion of the hollow space.

Description

Technical Field

[0001] The invention relates to an electric machine, in particular to an electronic commutation machine. The electric machine has a housing and a control device accommodated in the housing. The control device is configured to control the electric machine to generate a rotating magnetic field. Background Art

[0002] Patent document CN 107249965 A discloses an integrated electric power steering device, and patent document JP2017163810A discloses a motor control device. Summary of the invention

[0003] The object of the present invention is to improve an electric machine according to the prior art.

[0004] The above-mentioned object of the invention is achieved by an electric machine as described below: the electric machine has a housing and a control unit accommodated in the housing, wherein the control unit is designed to control the electric machine to generate a rotating magnetic field, wherein the housing has a housing cup and a housing cover surrounding the hollow space, and the electric machine has a bearing cover, wherein the bearing cover is accommodated in the housing cup and is connected to the housing cup in a heat-conducting manner, wherein the electric machine has a converter, which includes a semiconductor switch and which is connected to the bearing cover in a heat-conducting manner, and the electric machine has a cooling plate, which is connected to the housing cup and to at least one component or components of the control unit in a heat-conducting manner, wherein the bearing cover and the cooling plate surround a part of the hollow space between each other, and the control unit and the converter are accommodated in the part of the hollow space, wherein the cooling plate is embedded in the housing cup and the end face of the cooling plate is connected to the housing cup wall of the housing cup in a heat-conducting manner by means of a press connection, wherein the control unit and the converter are electrically connected to each other by means of at least one plug contact, and wherein in this case the components of the control unit and the semiconductor switches of the converter can be cooled independently of each other.

[0005] As described above, according to the present invention, the housing has a housing cup and a housing cover that surround the hollow space. The motor has a bearing cover accommodated in the housing cup, wherein the bearing cover is connected to the housing cup in a heat-conducting manner. The motor also has a cooling plate, which is connected to the housing cup and at least one component or multiple components of the control unit in a heat-conducting manner. The motor has a converter, which includes a semiconductor switch, wherein the semiconductor switch is connected to the bearing cover in a heat-conducting manner. The bearing cover and the cooling plate surround a portion of the hollow space between each other, wherein a control unit and a converter are accommodated in a portion of the hollow space. Components of the control unit, in particular electronic components, such as integrated circuits, capacitors or resistors, are therefore preferably extended into the hollow space formed between the cooling plate and the bearing cover. The semiconductor switch of the converter also extends into the hollow space thus formed, so that the motor can be formed particularly cheaply and compactly. Advantageously, the components of the control unit and the semiconductor switch of the converter can therefore be cooled independently of each other. Advantageously, different temperature levels can thus be generated at different heat sinks, so that compared to a common heat sink for semiconductors of the control unit and of the converter, heat loss from components having a lower temperature than other heat sinks can thus be easily dissipated.

[0006] In a preferred embodiment, the control unit and the converter are each electrically connected to one another by means of at least one plug contact, in particular individually for each phase. Advantageously, the control unit, for example including a printed circuit board, can thus be embedded together with the cooling plate as a compact assembly in the housing cup and connected to the converter by means of the plug contacts. The plug contacts are preferably each designed as cutting-clamping contacts. Thus, a cold weld connection can advantageously be produced.

[0007] In a preferred embodiment, the cooling plate is shrunk into the housing cup, wherein the end face of the cooling plate is connected to the housing cup wall of the housing cup in a heat-conducting manner by means of the squeeze connection thus produced. Advantageously, a friction-locking connection between the cooling plate and the housing cup wall can thus be formed. The machine can thus be produced inexpensively. For this purpose, the housing cup can be heated, for example, in the region in which the cooling plate is to be connected to the housing cup up to the edge of the housing cup, thereby expanding the diameter of the housing cup by heating. In the expanded state of the housing cup, the cooling plate can preferably already be embedded in the hollow space of the housing cup together with the control unit, in particular the circuit carrier comprising the control unit. After the housing cup has been cooled, the housing cup wall is shrunk onto the end face of the cooling plate, so that the cooling plate is fixedly connected to the housing cup in a friction-locking manner by means of the squeeze fit thus produced.

[0008] In a preferred embodiment, the housing cover is plugged into the cooling plate by means of a plug connector and / or is clipped into the cooling plate by means of a clip connector. The control unit can thus advantageously be introduced into the hollow space as a preassembled component together with the housing cover when the housing opening is closed. Further preferably, when the control unit is inserted during the closing of the housing cup opening, the control unit can be electrically connected to the converter.

[0009] The housing cover can, for example, have latching noses for latching with the housing cup, which are designed to engage in a positively locking manner in corresponding recesses of the housing cup and to latch there.

[0010] In a preferred embodiment, the housing cover has an outwardly directed plug connector, wherein the plug contacts of the plug connector are electrically connected to the control unit. The aforementioned components of the assembly comprising the housing cover and the control unit with the cooling plate can be plugged, screwed or welded together to produce a preassembled assembly.

[0011] In a preferred embodiment, the cooling plate has a protruding area at the end side and contacts the housing cup wall with the protruding area, in particular in a pressing manner. In this embodiment, the cooling plate can advantageously be pressed into the housing cup. The cooling plate thus advantageously does not need to be shrunk into the housing cup (as described above), so that the control unit can be connected to the housing cup in a simple manner by simply pressing the cooling plate into the housing cup.

[0012] In a preferred embodiment, the housing cover, the cooling plate and the control unit are connected to each other in a particularly rigid manner and together form a structural assembly which can be connected to the housing cup in a particularly detachable manner. Thus, the machine can be provided particularly inexpensively by inserting or pressing the structural assembly into the housing cup.

[0013] In a preferred embodiment, the converter is mechanically and electrically connected to the control unit and / or the cooling plate and is a component of the assembly. Advantageously, the converter, in particular the semiconductor switches of the converter, can therefore also be connected to the housing cup together with the control unit. Electrical connections, in particular output connections of the converter, for example phase connections of the converter connected to the stator coils of the motor stator, can be connected to the connections of the stator coils by means of plug connectors when the assembly is inserted into the housing cup.

[0014] In order to produce a heat-conducting connection with the bearing shield of the electric machine, the semiconductor switch of the converter can be connected to a heat-conducting agent, for example by dispensing, wherein after the structural component is introduced into the hollow space, the semiconductor switch of the converter is pressed onto the bearing shield, so that a heat-conducting layer is formed between the bearing shield and the semiconductor switch, which layer is formed by the heat-conducting agent. The heat-conducting agent is, for example, a heat-conducting paste or a resin filled with particles. The resin filled with particles, in particular filled with ceramic particles, can be hardened by means of ultraviolet radiation after the parts of the machine are assembled. For this purpose, the housing cup can have an opening, for example, through which a UV radiation source can be introduced into the hollow space in the area of ​​the heat-conducting connection.

[0015] The invention also relates to a method for producing an electric machine, wherein the electric machine has a housing cup and a housing cover, which is designed to close a housing opening of the housing cup. In the method, in one step, the bearing cover is inserted into the housing cup and connected to the housing cup in a form-fitting and / or force-fitting and heat-conducting manner.

[0016] In a further step, the cooling plate and the control unit and the converter connected to the control unit are embedded in the housing cup, so that the semiconductor switches of the converter are connected to the bearing cap in a heat-conducting manner. Here or in a further step, the cooling plate (extending parallel to the bearing cap) is connected in the housing cup in a force-fitting and / or form-fitting, heat-conducting manner. The heat-conducting connection is preferably produced by a press fit.

[0017] In a preferred variant of the method, the control unit, the cooling plate and the converter form a component which is connected, in particular rigidly, to the housing cover, wherein the housing opening is closed when the component is inserted into the housing cup. Advantageously, the machine can thus be provided inexpensively.

[0018] Preferably, the cooling plate is connected to the housing cup in a non-positive manner by pressing or shrinking when the assembly is inserted into the housing cup. This advantageously allows a good heat transfer from the cooling plate to the housing cup. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The invention will now be described below with reference to the drawings and further exemplary embodiments. Further advantageous embodiment variants result from the combination of the features described in the preferred embodiments and the drawings.

[0020] Figure 1 An exemplary embodiment of an electric machine is shown, the electrical components of which are compactly combined in a component assembly, wherein a cooling plate for cooling a control unit extends parallel to the bearing shield and the electrical components of the control unit are arranged in a cavity between the cooling plate and the bearing shield.

[0021] Figure 2An exemplary embodiment of a method for producing an electric machine is shown, in which electrical components of the machine are plugged into the housing cup of the machine before being inserted into the housing cup and subsequently introduced as a compact assembly into the housing cup, wherein the housing cup can thereby be closed.

[0022] Figure 3 An exemplary embodiment of a method for producing an electric machine is shown, in which a preassembled assembly comprising a housing cover, a control unit and a converter is connected to a housing cup and an opening of the housing cup is closed in the process. DETAILED DESCRIPTION

[0023] Figure 1 An embodiment of an electric motor 1 is shown. The electric motor 1 has a rotor 2, in particular a rotor of permanent magnet construction, and a stator 3, the stator comprising stator coils. The electric motor 1 also has a housing 4, which comprises a housing cup 5 and a housing cover 6. The housing cup 5 surrounds a hollow space 7, in which the rotor 2, the stator 3 and a converter for energizing the stator and a control unit for controlling the converter are accommodated. In this embodiment, the converter comprises a circuit carrier 12, which is connected to power semiconductors 16 and 17, in particular semiconductor switches, such as field effect transistors. In this embodiment, the control unit 14 comprises a circuit carrier, which is connected to a processing unit 15, in particular a microcontroller or a microprocessor, for electrically controlling the electric motor 1.

[0024] The electric machine 1 further comprises a bearing cover 11 which is accommodated in the hollow space 7 and is shrunk into the housing cup 5. The electric machine 1 further comprises a cooling plate 13 which is accommodated in the hollow space 7 and is shrunk into the housing cup 5. Both the bearing cover 11 and the cooling plate 13 are therefore heat-conducting, being connected to the housing cup 5 in a heat-conducting manner via the end side 22 of the cooling plate 13 or the end side 25 of the bearing cover 11.

[0025] The control unit, in particular its components which generate heat loss, such as processing unit 15 , is connected to cooling plate 13 in a thermally conductive manner and can conduct the heat loss via a circuit carrier of control unit 14 to cooling plate 13 .

[0026] In this exemplary embodiment, the converter comprises a circuit carrier 12, for example a ceramic circuit carrier, which is connected in a heat-conducting manner to the bearing cover 11. The semiconductor switches 16 and 17 can thus conduct the lost heat via the circuit carrier 12 (especially in a slug-down arrangement) to the bearing cover 11, from which the lost heat 40 can be dissipated via the end face 25 of the bearing cover 11 to the housing cup 5.

[0027] In this embodiment, the bearing shield 11 has a recess for a rotor bearing 38, in which the rotor bearing 38 is arranged. In this embodiment, the rotor 2 comprises a rotor shaft 41, which protrudes through a recess in the bearing shield 11 and through a recess in the circuit carrier 12. In this embodiment, the circuit carrier of the control unit 14 and the circuit carrier 12 of the converter enclose between each other a portion 35 of the hollow space 7 extending along the longitudinal axis 10 of the electric machine 1 over the longitudinal section 9. In this embodiment, the longitudinal axis 10 extends coaxially with respect to the longitudinal extension of the rotor shaft 41. In this embodiment, the control unit has a rotor position sensor 18, in particular a Hall sensor, an AMR sensor (AMR=Anisotrope-Magneto-Resistive) or a GMR sensor (GMR=Giant-Magneto-Resistive), which is connected to the circuit carrier of the control unit 14 and is opposite to the end of the rotor shaft 41 and can therefore detect the rotor position of the rotor 2.

[0028] Electrical components, in particular electrical components, connected to the circuit carrier of the control unit 14 and the converter 12 extend into the portion 35 of the hollow space 7 formed on the longitudinal section 9. The electrical components connected to the circuit carrier 12 of the converter and the electrical components connected to the circuit carrier of the control unit 14 therefore extend toward each other, in particular along the longitudinal axis 10. In this embodiment, the circuit carrier 12 of the converter and the circuit carrier of the control unit 14 are mechanically connected to each other by means of a connecting element in the form of a tab, one of which 34 is shown as an example. The control unit, in particular the circuit carrier of the control unit 14, is electrically connected to the circuit carrier 12 of the converter and thus to the converter by means of connecting wires. The converter can thus receive control signals from the control unit, in particular the processing unit 15, via the connecting wires. One of the connecting wires, which is configured as a plug contact 20, is shown as an example. The connecting wire leads into a socket configured as a mating plug contact 19, which is electrically connected to the circuit carrier 12 of the converter. The circuit carrier of the control unit 14 can thus be plugged together with the cooling plate 13 for connection to the converter.

[0029] The connecting element 34 is also designed as a plug element for this purpose. The control unit and the converter can thus be inserted as a preassembled, in particular plug-in assembly into the hollow space 7 of the housing cup 5 through the housing cup opening 8 .

[0030] In this embodiment, the circuit carrier of the control unit, in particular the control unit 14, has plug connectors 21 and 23, in particular sockets, pointing toward the housing cover 6 and each projecting into the hollow space surrounded by the housing cover 6. In this embodiment, the housing cover 6 has a plug connector 26 integrally formed on the housing cover 6, which includes plug contacts, one of which 27 is shown as an example. The plug contact 27 is introduced through the housing cover 6 into the hollow space surrounded by the housing cover 6 and can be introduced into the plug connector 21 there. In this embodiment, the cooling plate 13 is connected to the housing cover 6 by means of a mechanical plug connector 33, which is in particular detachable. The housing cover 6 can thus be plugged in a simple manner not only electrically but also mechanically to the circuit carrier of the control unit 14 and the cooling plate 13. In this embodiment, the plug connector 33 is electrically and mechanically connected to the circuit carrier 25, in particular an EMC filter (EMC=electromagnetic compatibility).

[0031] Therefore, after being plugged into the cooling plate 13 and the circuit carrier of the control unit 14, and after the circuit carrier 12 of the converter is further plugged into the control unit, in particular the circuit carrier of the control unit 14, the housing cover 6 can be introduced into the hollow space 7 of the housing cup 5 through the housing cup opening 8 as a pre-assembled structural component.

[0032] Figure 2 shows the connection Figure 1 1 and the method steps of the bearing cap 11 and the housing cup 5 are shown in FIG. For this purpose, the housing cup 5 is heated by means of heat radiation 29 over a longitudinal section 28 along the longitudinal axis 10 from the connection point of the bearing cap 11 and the housing cup 5 to the housing cup edge of the housing cup 5. The housing cup 5 is thus expanded in this region along the longitudinal section 28, so that its diameter increases after heating. The bearing cap 11 can then be introduced into the housing cup 5 without friction in the region of the longitudinal section 28. After the housing cup 5 has cooled over the longitudinal section 28, the housing cup 5, in particular the housing cup wall, shrinks onto the bearing cap 11 and is pressed against the end side of the bearing cap 11, so that a press fit can be produced.

[0033] Figure 3 Shown for production Figure 1 An exemplary embodiment of method steps for an electric machine 1 is shown in FIG. Figure 3 The figure shows a preassembled assembly 32, which comprises a housing cover 6, a control unit 14 plugged into the housing cover 6 and comprising a circuit carrier and a cooling plate 13, and a converter plugged into the control unit, the converter comprising a circuit carrier 12. In this embodiment, the circuit carrier 12 of the converter is welded to power semiconductors, in particular semiconductor switches 36 and 37, which are connected to the power semiconductors. Figure 1Unlike the one shown in FIG. 1 , the semiconductor switches 36 and 37 do not extend into the hollow space formed on the longitudinal section 9 between the circuit carrier 12 of the converter and the circuit carrier of the control unit 14, but extend from the circuit carrier 12 of the converter toward the bearing cover 11. The semiconductor switches 36 and 37 are thus connected to the bearing cover 11 in a heat-conducting manner by means of slug-up technology.

[0034] Figure 2 The bearing cap 11 shown in Figure 3 1 ' is shown as a bearing cap 11' that is shrunk into the housing cup 5. A heat conducting agent 30, in particular a heat conducting paste or a heat conducting adhesive, is applied to the bearing cap 11, in particular opposite the semiconductor switches 36 and 37. The component 32 can thus be inserted into the housing cup 5 through the housing cup opening 8 until the semiconductor switches 36 and 37 are placed on the bearing cap 11. The housing cup 5 is then closed by the housing cover 6.

[0035] The housing cup 5 can be heated by means of heat radiation 29 before being joined to the assembly 32 in a longitudinal section 31 which extends from the connection point of the cooling plate 13 along the longitudinal axis 10 to the edge of the housing cup. The cooling plate 13 can thus shrink into the housing cup 5 after being inserted into the hollow space 7 of the housing cup 5 and after the housing cup 5 has cooled. Figure 3 Unlike what is shown in FIG. 1 , the cooling plate 13 can be pressed into the housing cup 5 .

Claims

1. An electric motor (1), comprising a housing (4) and a control unit (14) accommodated in the housing (4), wherein the control unit (14) is configured to control the electric motor (1) to generate a rotating magnetic field, in, The housing (4) comprises a housing cup (5) and a housing cover (6) which surround the hollow space (7), and the electric machine (1) comprises a bearing cover (11). The bearing cover (11) is accommodated in a housing cup (5) and is connected to the housing cup (5) in a heat-conducting manner, the electric machine (1) has a converter (12), the converter includes semiconductor switches (16, 17, 36, 37), and the semiconductor switches (16, 17, 36, 37) are connected to the bearing cover (11) in a heat-conducting manner, The electric machine (1) has a cooling plate (13) which is heat-conductingly connected to the housing cup (5) and to at least one component or multiple components of the control unit (14). The bearing cover (11) and the cooling plate (13) surround a portion (35) of the hollow space (7) between each other, and a control unit (14) and a converter (12) are accommodated in the portion (35) of the hollow space (7). The cooling plate (13) is embedded in the housing cup (5). The end face (22) of the cooling plate (13) is connected to the housing cup wall of the housing cup in a heat-conducting manner by means of an extrusion connection. The control unit (14) and the converter (12) are electrically connected to one another by means of at least one plug contact (19, 20). And wherein in this case components of the control unit and semiconductor switches (16, 17) of the converter can be cooled independently of one another.

2. The electric machine (1) according to claim 1, characterized in that Each phase of the converter (12) is electrically contacted with a control unit (14) by means of plug contacts (19, 20).

3. The electric machine (1) according to claim 1 or 2, characterized in that The plug contact is designed as a cutting and clamping contact.

4. The electric machine (1) according to claim 1 or 2, characterized in that The housing cover (6), the cooling plate (13) and the control unit (14) are connected to one another and together form a preassembled component which is detachably connected to the housing cup (5), wherein the converter and the control unit can be electrically connected by means of the at least one plug contact when the preassembled component is inserted.

5. The electric machine (1) according to claim 4, characterized in that The converter (12) is mechanically and electrically connected to a control unit (14) and / or a cooling plate (13) and is a component of the preassembled assembly.

6. The electric machine (1) according to claim 1 or 2, characterized in that The press connection is produced by means of constriction (29).

7. The electric machine (1) according to claim 1 or 2, characterized in that The press connection is produced by pressing in.

8. The electric machine (1) according to claim 1 or 2, characterized in that The housing cover (6) is plugged into the cooling plate (13) by means of a plug connector (21, 33) and / or is clipped into the cooling plate (13) by means of a clip connector.

9. The electric machine (1) according to claim 1 or 2, characterized in that The cooling plate (13) has a convex area on the end face (22) and contacts the wall of the housing cup (5) in a pressing manner with the convex area.

10. Method for producing an electric machine (1), wherein the electric machine comprises a housing cup (5) and a housing cover (6), the housing cover being designed to close a housing opening of the housing cup, In one step, the bearing cover (11) is inserted into the housing cup (5) and connected to the housing cup (5) in a form-fitting and / or force-fitting and heat-conducting manner, In a further step, the cooling plate (13) and the control unit (14) and the converter (12) connected to the control unit (14) are embedded in the housing cup (5) in such a way that the semiconductor switches (16, 17, 36, 37) of the converter (12) are connected to the bearing cover (11) in a heat-conducting manner. The cooling plate (13) is connected to the housing cup (5) in a force-fitting and / or form-fitting manner and in a heat-conducting manner in a manner extending parallel to the bearing cover (11). The end face (22) of the cooling plate (13) is connected to the housing cup wall of the housing cup in a heat-conducting manner by means of a press connection. The converter is electrically connected to the control unit (14) by means of plug contacts (19, 20) before or during insertion into the cooling plate (13) and the control unit (14), And wherein in this case components of the control unit and semiconductor switches (16, 17) of the converter can be cooled independently of one another.

11. The method according to claim 10, characterized in that The control unit (14), the cooling plate (13) and the converter (12) form a subassembly (32) which is connected to the housing cover, so that the housing cup opening (8) is closed when the subassembly (32) is inserted into the housing cup (5).

12. The method according to claim 10 or 11, characterized in that: The cooling plate (13) is connected to the housing cup (5) in a force-fitting manner by pressing in or shrinking (29) when the component (32) is inserted into the housing cup (5).

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