Electric machine with cooling function

Abstract

For an electric machine (100) having an associated power electronics (150) and a motor housing (105), a motor unit (110) is arranged in the motor housing, on an end side (107) of the motor housing (105) a cooling body (130) is fixed, which has at least one cooling channel (140) open toward the end side (107) in order to be able to cool the end side (107) by means of a cooling liquid flowing along the end side, wherein the cooling body (130) constitutes a receptacle (135) which is separated from the at least one cooling channel (140) in a liquid-tight manner, which is at least section-wise surrounded by the at least one cooling channel (140), and wherein the receptacle (135) is configured for at least partially accommodating the associated power electronics (150).

Description

Technical Field

[0001] This invention relates to an electric motor having associated power electronics and a motor housing, in which a motor unit is arranged, and a cooling element is fixed to one end of the motor housing. Furthermore, this invention also relates to a corresponding cooling element. Background Technology

[0002] An existing technology provides for an electric motor having associated power electronics and a motor housing, in which a motor unit is arranged. In this motor, cooling of the associated power electronics and the motor unit is achieved by a cooling body arranged on the motor housing, particularly by a cooling body arranged on the end side of the motor housing. For this purpose, the cooling body has a liquid-sealed cooling channel separate from the motor housing, through which cooling liquid is guided. Summary of the Invention

[0003] This invention relates to an electric motor having associated power electronics and a motor housing, in which a motor unit is arranged. A cooling body is fixed to an end side of the motor housing, the cooling body having at least one cooling channel open toward the end side to enable cooling of the end side by a cooling liquid flowing along that end side. The cooling body constitutes a liquid-sealed receiving portion separated from the at least one cooling channel, the receiving portion being at least sectionally surrounded by the at least one cooling channel. The receiving portion is configured to at least partially accommodate the associated power electronics.

[0004] A compact motor, which advantageously requires little structural space, can be provided by means of cooling channels that open towards the end sides of the cooling body. Improved cooling of the motor housing is achieved here because the cooling liquid flowing through the cooling body directly contacts the end sides of the motor housing. Furthermore, by using a liquid-sealing method to close the cooling channels towards the end sides of the motor housing, materials used to construct the cooling body can be saved.

[0005] According to one embodiment, at least one cooling channel is provided with multiple cooling sleeves (Kühlnippel).

[0006] Therefore, it is possible to further improve the corresponding cooling function achieved by the cooling body.

[0007] Preferably, at least one cooling channel constitutes multiple cooling tanks.

[0008] Therefore, the surface area formed by the cooling channels for cooling the motor housing can be increased in a simple way and by a simple method.

[0009] Preferably, multiple cooling tanks are fluidly interconnected through multiple connecting channels.

[0010] Therefore, it is possible to easily and uncomplicatedly guide the coolant between adjacent cooling tanks in the cooling channel.

[0011] Multiple cooling sleeves are preferably arranged in multiple cooling tanks.

[0012] Therefore, it is possible to further improve the cooling that can be achieved through the cooling sleeve.

[0013] Preferably, the multiple connecting channels have multiple deflection elements so as to deflect the cooling liquid flowing through the multiple connecting channels from the multiple connecting channels into multiple cooling tanks.

[0014] Therefore, it can be ensured that the cooling liquid flowing from the connecting channel into the cooling tank flows through the cooling tank, so as to increase the corresponding cooling through the cooling liquid.

[0015] According to one embodiment, the cooling body has an inlet opening for introducing coolant into at least one cooling channel and at least one outlet region for allowing coolant to flow out of the at least one cooling channel. The at least one cooling channel spans an angle range of at least 180° between the inlet opening and the at least one outlet region.

[0016] Therefore, a relatively large angular range of the cooling body can be applied in a simple way to achieve the appropriate cooling function.

[0017] According to one embodiment, the coolant is liquid-sealed, particularly by welding, to the motor housing.

[0018] Therefore, it is advantageous to omit the use of additional components, such as seals and suitable fixing mechanisms, which would otherwise be necessary for sealing the cooling element relative to the motor housing and for securing the cooling element to the motor housing. However, it should be noted that the cooling element does not necessarily need to be forcibly, for example, welded to the motor housing. More precisely, suitable seals with corresponding fixing mechanisms can also be used in a simplified implementation.

[0019] According to one embodiment, the motor housing is provided with a cover that liquid-tightly seals the motor housing and forms an end side of the motor housing.

[0020] Therefore, the motor housing can be sealed in a liquid-tight manner and by a simple method.

[0021] Furthermore, the present invention relates to a cooling body for an electric motor, wherein power electronic devices are associated with the motor and the motor has a motor housing with end sides in which motor units can be arranged. The cooling body has at least one open cooling channel extending longitudinally and can be fixed to the end side of the motor housing such that the end side, extending longitudinally, closes at least one open cooling channel to allow cooling fluid flow through the cooling channel. The cooling body constitutes a liquid-sealed receiving portion separated from the cooling channel, the receiving portion being at least sectionally surrounded by at least one open cooling channel. The receiving portion is configured to at least partially accommodate the associated power electronic devices. Attached Figure Description

[0022] The invention is described in detail below with reference to embodiments shown in the accompanying drawings. Wherein are shown:

[0023] Figure 1 Show along Figure 4 A cross-section of an exemplary motor observed through section line II, the motor having a motor housing on which a cooling element is fixed.

[0024] Figure 2 Show along Figure 4 The motor housing with a cooling element fixed thereon, as observed by section line II-II. Figure 1 A cross-section of an exemplary motor,

[0025] Figure 3 Show along Figure 4 The motor housing with a cooling element fixed thereon, as observed by section line III-III. Figure 1 A cross-section of an exemplary motor,

[0026] Figure 4 Show Figures 1 to 3 An exemplary perspective view of a motor, in which the cooling element is shown in section.

[0027] Figure 5 Show Figures 1 to 4 The cooling body, along its direction Figures 1 to 4 A perspective view of the lower side of the motor housing, and

[0028] Figure 6 Show Figures 1 to 4 The cooling body, along its back Figures 1 to 4 A perspective view taken from the top side of the motor housing. Detailed Implementation

[0029] In the accompanying drawings, elements with the same or similar functions are given the same reference numerals and are described more accurately only once.

[0030] Figure 1 An exemplary motor 100 having a motor housing 105 is shown. The motor housing 105 forms an internal space 106 in which a motor unit 110 is arranged. The motor unit 110 exemplaryly includes a motor shaft 115 rotatably supported in the motor housing 105 by suitable bearing elements. Exemplarily, the rotor shaft 115 is supported in the motor housing 105 by rolling bearings 117, 119, and in particular by ball bearings, and exemplaryly provided is an assembly aid 167, which is preferably removed from the motor after the motor 100 has been assembled accordingly.

[0031] It should be noted that, for the sake of simplicity and clarity in the accompanying drawings, other components of the motor unit 110, such as the rotor and / or stator, are not shown. However, such components or assemblies of the motor unit 110 are well known to those skilled in the art, and thus their detailed illustrations can be omitted.

[0032] Schematic, the motor housing 105 has housing walls 122, 124 formed by an outer wall 122 and an inner wall 124. The housing walls 122, 124 are located in... Figure 1 The lower side of the motor housing 105 is closed by the lower housing flange 125. A cover 120 is preferably provided on the end side 107 opposite the lower housing flange 125 in its axial direction. This cover preferably liquid-tightly seals the motor housing 105 and forms the end side 107 of the motor housing 105.

[0033] According to one embodiment, a cooling body 130 is arranged on an end side 107 of the motor housing 105, the cooling body having at least one cooling channel 140 open toward the end side 107 so that cooling of the end side 107 can be achieved by cooling liquid flowing along the end side. The cooling body 130 preferably constitutes a receiving portion 135 that is liquid-sealed and separated from the at least one cooling channel 140, the receiving portion being at least sectionally surrounded by the at least one cooling channel 140. The receiving portion 135 is preferably configured to at least partially accommodate the associated power electronic device 150.

[0034] The power electronic device 150 is schematically formed from a plurality of electrolytic capacitors (“Elkos”), and for convenience of description, is referred to below as “electrolytic capacitor 150”. In the electrolytic capacitor 150, each individual electrolytic capacitor is schematically and individually provided with reference numeral 151.

[0035] Preferably, the electrolytic capacitor 150 is fixed to a corresponding retainer 152 arranged in the receiving portion 135. The retainer 152 is preferably constructed in the pattern of a stamped grid, to which the electrolytic capacitor 150 is preferably welded. The retainer 152 is schematically fixed in the receiving portion 135, wherein suitable thermal paste can be provided in the areas between the electrolytic capacitor 150 and the coolant 130, respectively. Schematally, thermal paste, indicated by reference numeral 154, is provided in the area between the electrolytic capacitor 151 and the coolant 130 located in the receiving portion 135.

[0036] According to one embodiment, the electrolytic capacitor 150 is part of the electronic unit 160 of the motor 100. Suitable electronic units that can be used to implement the electronic unit 160 and are electrically connected to the electrolytic capacitor 150 are well known to those skilled in the art, and therefore, for the sake of brevity and clarity of the drawings, detailed illustrations of the electronic unit 160 are omitted herein, especially since the electronic unit 160 itself is not part of the present invention.

[0037] Schematic, the electronic unit 160 is arranged in a housing cover 165, which forms an internal space 168 for accommodating the electronic unit 160. Preferably, the housing cover 165 is connected to the motor housing 105, for example, by a suitable fastening mechanism, such as bolts.

[0038] A cooling element 130 is preferably arranged in the area between the housing cover 165 and the motor housing 105. Preferably, the cooling element 130, the housing cover 165, and the motor housing 105 are releasably connected to each other via a suitable fixing mechanism, such as bolts. Here, the cooling element 130 is as follows: Figure 1 As shown, it is fluid-tightly connected to the motor housing 105 by suitable sealing elements, especially sealing rings 172 and 174.

[0039] However, it should be noted that a permanent connection between the cooling element 130 and the motor housing 105, especially a permanent connection between the cooling element 130 and the cover 120 on the end side 107, is also feasible. Such a permanent connection can be achieved, for example, by welding.

[0040] Sealing ring 172 schematically seals the coolant 130 in a liquid-tight manner relative to the outer wall 122 of the motor housing 105, while sealing ring 174 seals the coolant 130 in a liquid-tight manner toward the cover 120, as shown in the region of rotor shaft 115, which exemplarily extends through the coolant 130 through an opening 139 in the coolant 130. Here, rotor shaft 115 preferably extends through the coolant 130 in its axial direction.

[0041] According to one embodiment, the cooling body 130 has an inlet opening 131 to allow cooling liquid to be introduced into the cooling body 130 or into at least one cooling channel 140 of the cooling body 130. For this purpose, an inlet pipe 132 is schematically arranged in the region of the inlet opening 131. Furthermore, the cooling body 130 has at least one outlet region (…). Figure 3 (136 in the text) so that coolant can flow out from at least one cooling channel 140. Preferably, at least one cooling channel 140 has an inlet opening 131 and at least one outlet area ( Figure 3 The 136) spans a pre-given angular range, such as in Figure 5 As described in [the text].

[0042] Preferably, a plurality of cooling sleeves 145 are arranged in at least one cooling channel 140. The plurality of cooling sleeves 145 are used to improve the cooling function of the cooling body 130.

[0043] Cooling element 130 is located at the bottom, especially in Figure 5 and Figure 6 Detailed description is provided below. Figure 5 The image shows the cooling element 130 as viewed along the direction of arrow V. Figure 1 The top view from the bottom (in the middle), while Figure 6 The image shows the cooling element 130 as viewed along the direction of arrow VI. Figure 1 (The top view of the middle)

[0044] As described above, the cooling body 130 has at least one outlet area ( Figure 3 136), so that coolant can flow out from at least one cooling channel 140 of the coolant body 130. Here, the outlet area ( Figure 3 (136) can be directly equipped with an export control pipe. Alternatively, the export area ( Figure 3 (136) can be connected to an optional cooling channel 180, which is constructed in the housing walls 122, 124 of the motor housing 105.

[0045] Schematic, an optional cooling channel 180 is constructed within the housing walls 122, 124 defining the internal space 106, between the outer wall 122 and the inner wall 124. Here, the inner wall 124 exemplarily has radially outwardly extending ribs 126, which preferably extend spirally or coiledly around the inner wall 124 and thus constitute the optional cooling channel 180, preferably spirally or coiled. Alternatively, the ribs 126 may also be constructed on the outer wall 122 and extend radially inward.

[0046] Preferably, the optional cooling channel 180, which is spiral or coiled, has an outlet opening 108 in the region of the lower housing flange 125. An outlet fitting 109 is exemplarily arranged in the region of the outlet opening 108 to allow coolant to flow out from the optional cooling channel 180. By providing the optional cooling channel 180, effective cooling of the motor housing 105 and thus the motor unit 110 disposed therein can be achieved.

[0047] Figure 2 Regarding Figure 1 A view showing the rotor shaft 115 rotated approximately 90° is shown. Figure 1 The motor 100. As described above, the motor 100 includes a cooling element 130 disposed between the housing cover 165 and the motor housing 105.

[0048] and Figure 1 compared to, Figure 2 Suitable fixing mechanisms 210 (schematically constructed according to the bolt pattern) and 220 (also schematically constructed according to the bolt pattern) are shown. Bolt 210 preferably releasably fixes housing cover 165 to cooling body 130, and bolt 220 preferably releasably fixes cooling body 130 to motor housing 105.

[0049] However, it should be noted that alternative fixing mechanisms, such as clips, can also be used. Furthermore, bolts with nuts can be used instead of bolts alone, and so on.

[0050] Figure 3 Regarding Figure 1 A view showing the rotor shaft 115 rotated approximately 30° is shown. Figure 1 The motor 100. As described above, the motor 100 includes a cooling element 130 disposed between the housing cover 165 and the motor housing 105.

[0051] and Figure 1 compared to, Figure 3 An outlet region 136 of the coolant 130 is shown, which is used to allow coolant to flow out from at least one cooling channel 140 of the coolant 130. For this purpose, the outlet region 136 forms an outlet opening 137. As shown above... Figure 1 As mentioned above, the outlet opening 137 can be directly equipped with a suitable outlet pipe, for example... Figure 1 The outlet pipe 109 is provided so that the cooling liquid can be directly discharged from the cooling body 130.

[0052] However, according to one embodiment, the outlet opening 137 is connected to the transition channel 310. Figure 1An optional cooling channel 180 is connected, which is constructed in the housing walls 122, 124 of the motor housing 105. Therefore, coolant can be guided from the cooling channel 140 of the coolant body 130 via the transition channel 310 to the housing walls 122, 124, and can flow there through the optional cooling channel 180 to reach… Figure 1 The outlet opening 108 is as described above.

[0053] also, Figure 3 An exemplary phase conductor 320 is shown, which leads from the motor unit 110 to the electronics unit 160 and electrically connects them to each other. The phase conductor 320 is exemplary led from the internal space 106 to the housing cover 165 via a conductor guide element 330. The conductor guide element 330 is preferably fluid-tightly connected to the end face 107 or cover 120 of the motor housing 105.

[0054] Figure 4 It shows Figures 1 to 3 The motor 100 has a cooling body 130 schematically cut perpendicular to the axis of rotation of the rotor shaft 115. Figure 4 The corresponding section lines II, II-II, and III-III are shown, along which the following is achieved Figures 1 to 3 A cross-sectional view. In particular, Figure 4 Show Figures 1 to 3 The structure has at least one cooling passage 140 that is open to the cover 120 facing the motor housing 105.

[0055] Cooling element 130 has Figures 1 to 3 At least one cooling channel 140 is provided, preferably having multiple groove-like structures 510, which are referred to hereinafter as "cooling channels 510" for simplicity. These cooling channels 510 are fluidly connected to each other via a plurality of associated connecting channels 520. Schematically, for the sake of simplicity and clarity in the figures, the cooling channel 510 comprises six cooling channels, wherein typically only a single cooling channel is provided with a reference numeral 510. These six cooling channels 510 are connected by five connecting channels 520, wherein, for the sake of simplicity and clarity in the figures, only a single connecting channel is representatively provided with a reference numeral 520. Here, the connecting channel 520 connects two adjacent cooling channels 510 in the circumferential direction of the cooling body 130.

[0056] Schematic, the first cooling tank 510 is arranged in Figure 1 The area of ​​the inlet nozzle 132 or inlet opening 131. From this area, the cooling channel 140 extends circumferentially around the cooling body 130. Figures 1 to 3The receiving portion 135 extends toward the outlet opening 137 in the outlet region 136. Here, the at least one cooling channel 140 preferably spans an angle range of at least 180° and schematically spans an angle range of approximately 270°. However, this angle range can be determined according to specific conditions. Figures 1 to 3 The motor unit 110 or cover 120 of the motor housing 105 in the motor housing 105 can be modified or constructed according to the application.

[0057] Figure 5 from Figures 1 to 4 An directional view of the motor housing 105 shows Figures 1 to 4 The cooling element 130, or rather its lower side. Here, Figure 5 Special Note Figure 4 The angle range 540 between the inlet opening 131 and the outlet area 136. The angle range 540 is exemplarily approximately 270°, as in... Figure 4 As described in [the text].

[0058] Furthermore, as in Figure 4 As described herein, at least one cooling channel 140 of the cooling body 130 has according to Figures 1 to 3 Multiple cooling sleeves 145. Furthermore, the at least one cooling channel 140 preferably has a cooling groove 510, which is fluidly interconnected by multiple connecting channels 520. Preferably, the multiple cooling sleeves 145 are arranged in the cooling groove 510.

[0059] For example, a single cooling tank of cooling tank 510 is indicated by reference numeral 512, in which a plurality of cooling sleeves 145 are arranged, for example, a cooling sleeve indicated by reference numeral 146. The cooling tank 512 is schematically connected to another cooling tank, which is schematically indicated by reference numeral 514, via a connecting channel of a plurality of connecting channels 520, which is indicated by reference numeral 522.

[0060] According to one embodiment, the multiple connecting channels 520 have multiple deflecting elements 530 to deflect cooling liquid flowing through the multiple connecting channels 520 into the cooling tank 510. This ensures that the cooling liquid is directed into the cooling tank 510 and flows there around the multiple cooling sleeves 145. Exemplarily, the deflecting elements 530, indicated by reference numeral 532, are provided on the connecting channels 522.

[0061] According to one embodiment, the cooling body 130 further has a plurality of through openings 550. The plurality of through openings 550 are used to accommodate a plurality of associated wire guiding elements (…). Figure 3(330 in the text), the conductor guiding element can be used to guide the respective phase conductors from... Figures 1 to 3 The motor unit 110 is led to Figures 1 to 3 The electronic unit 160. Schematic, a single through-hole of a plurality of through-holes 550 is representatively indicated by reference numeral 558, said through-hole being used to accommodate... Figure 3 The wire guiding element 330.

[0062] Figure 6 from Figures 1 to 3 Viewed from the direction of the housing cover 165. Figures 1 to 5 The cooling body 130, or its upper side, as described above, includes a structure for housing... Figures 1 to 3 The electrolytic capacitor 150 has a receiving portion 135. Furthermore, the cooling body 130 preferably has a plurality of cooling surfaces 610 on its upper side, which are preferably used for cooling the associated power semiconductor. For this purpose, the cooling surfaces 610 are provided with heat-dissipating elements according to one embodiment, wherein, for the sake of brevity and clarity in the drawings, a representative individual heat-dissipating element is designated 612. These heat-dissipating elements 612 are used to achieve a tight thermal connection between the associated power semiconductor and the cooling body 130 and thus ensure proper heat dissipation. Schematably, the heat-dissipating element 612 has a direct-bonded copper-substrate (“DBC substrate”), which preferably carries the associated power semiconductor and is connected to the cooling body 130 via a suitable thermally conductive medium, such as thermal paste, thermally conductive adhesive, and / or thermally conductive film. Alternatively, instead of a suitable thermally conductive medium, a brazing connection may also be provided between the DBC substrate and the cooling body 130 for heat transfer.

[0063] Furthermore, according to one embodiment, a plurality of axial protrusions 620, 630 are optionally constructed on the upper side of the cooling body 130, the axial protrusions being referred to hereinafter also as "cooling domes". A plurality of first cooling domes 620 (wherein, for the sake of simplicity and clarity of the drawings, a single cooling dome is typically indicated only by reference numeral 622) schematically form an externally interrupted cooling dome ring on the upper side of the cooling body 130. Similarly, a plurality of second cooling domes 630 (wherein, for the sake of simplicity and clarity of the drawings, a single cooling dome is typically indicated only by reference numeral 632) constitute an internal cooling dome ring. The plurality of cooling domes 620, 630 are preferably used for support. Figures 1 to 3 The corresponding circuit board of the electronic unit 160. Therefore, the circuit board can be effectively cooled by the multiple cooling domes 620, 630, and in particular, specific components arranged on the circuit board, such as driver modules and central processing units (“CPUs”), can be effectively cooled.

Claims

1. An electric motor (100) having associated power electronics (150) and a motor housing (105) in which a motor unit (110) is arranged, wherein a cooling body (130) is fixed on an end side (107) of the motor housing (105), the cooling body having at least one cooling channel (140) open toward the end side (107) for cooling the end side (107) by a cooling liquid flowing along the end side, wherein the cooling body (130) constitutes a receiving portion (135) liquid-sealed and separated from the at least one cooling channel (140), the receiving portion being at least segmentally surrounded by the at least one cooling channel (140), and wherein the receiving portion (135) is configured to at least partially accommodate the associated power electronics (150).

2. The motor according to claim 1, characterized in that, The at least one cooling channel (140) is provided with a plurality of cooling sleeves (145).

3. The motor according to claim 2, characterized in that, The at least one cooling channel (140) constitutes a plurality of cooling tanks (510).

4. The motor according to claim 3, characterized in that, The plurality of cooling tanks (510) are fluidly connected to each other via a plurality of connecting channels (520).

5. The motor according to claim 3, characterized in that, The plurality of cooling sleeves (145) are arranged in the plurality of cooling tanks (510).

6. The motor according to claim 4, characterized in that, The multiple connecting channels (520) have multiple deflection elements (530) to enable the cooling liquid flowing through the multiple connecting channels (520) to be deflected from the multiple connecting channels (520) into the multiple cooling tanks (510).

7. The motor according to any one of claims 1 to 6, characterized in that, The cooling body (130) has an inlet opening (131) and at least one outlet region (136), the inlet opening being able to introduce cooling liquid into the at least one cooling channel (140), and the outlet region being able to allow cooling liquid to flow out from the at least one cooling channel (140), wherein the at least one cooling channel (140) spans an angle range of at least 180° between the inlet opening (131) and the at least one outlet region (136).

8. The motor according to any one of claims 1 to 6, characterized in that, The cooling body (130) is liquid-sealed to the motor housing (105).

9. The motor according to any one of claims 1 to 6, characterized in that, The motor housing (105) is provided with a cover (120) that liquid-tightly seals the motor housing (105) and forms an end side (107) of the motor housing (105).

10. The motor according to any one of claims 1 to 6, characterized in that, The cooling body (130) is connected to the motor housing (105) by welding.

11. A cooling body (130) for an electric motor (100), power electronics (150) associated with the electric motor and the electric motor having a motor housing (105) with an end side (107) in which a motor unit (110) can be arranged, wherein the cooling body (130) has at least one open cooling channel (140) extending longitudinally therein and can be fixed to the end side (107) of the motor housing (105) such that the end side (107) extends longitudinally therein to close the at least one open cooling channel (140) so that a flow of cooling liquid can be directed through the cooling channel (140), wherein the cooling body (130) constitutes a liquid-sealed accommodating portion (135) separated from the cooling channel (140), the accommodating portion being at least segmentally surrounded by the at least one open cooling channel (140), and wherein the accommodating portion (135) is configured to at least partially accommodate the associated power electronics (150).

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