Junction Assembly Heat Dissipation and Sealing Configuration

Abstract

Disclosed herein is a junction assembly. The junction assembly includes a junction housing configured to support a phase bar assembly. A heat sink contacts at least a portion of the junction housing, and a bus bar is disposed adjacent to the junction housing. At least one fastener attaches the junction housing, the heat sink, and the bus bar relative to one another. At least one heat sink seal is provided at an interface defined between the heat sink and the junction housing.

Description

Technical Field

[0001] (Cross - Reference to Related Applications) This application claims priority to U.S. Patent Application No. 17 / 337,160, filed on June 2, 2021, the entire disclosure of which is incorporated herein by reference.

[0002] This disclosure relates to a heat dissipation configuration for a junction ンア assembly.

Background Art

[0003] Junction ンア assemblies are generally well - known in electric motor (e - motor) applications. Generally, a junction ンア assembly is configured to transmit power from a power electronics unit (PEU) to an e - motor. Since electrical components are sensitive, it is important to maintain a specific sealing configuration (i.e., Ingress Protection (IP) against 69K ingress) between all assemblies and interfaces involved. There are various known methods and configurations to achieve this specific sealing requirement.

[0004] Also, in a junction ンア assembly, heat dissipation is also a problem. In one aspect, mainly, heat dissipation is addressed by arranging a forced fluid circuit for removing heat around the heat - generating components. In these configurations, additional sealing components, pumps, filters, and other components are required. All of these mechanisms increase the cost and complexity of the assembly. Furthermore, the performance of a fluid - type radiator decreases over time due to wear, contamination, and other factors.

[0005] Therefore, there is a general need for an improved assembly that achieves the necessary sealing function while providing heat dissipation.

Summary of the Invention

Problems to be Solved by the Invention

[0006] The present disclosure provides an improved passive heat dissipation configuration for a junction assembly, which also provides the necessary sealing characteristics.

Means for Solving the Problem

[0007] In one aspect, a junction housing configured to support a phase bar assembly is provided. A heat sink is in contact with at least a portion of the junction housing, and a bus bar is disposed adjacent to the junction housing. At least one fastener attaches the junction housing, the heat sink, and the bus bar to each other. At least one heat sink seal is provided at an interface defined between the heat sink and the junction housing.

[0008] In one aspect, the junction housing includes a first junction housing and a second junction housing, and a junction housing seal is disposed between the first junction housing and the second junction housing.

[0009] For example, at least one non-through clinch nut can be disposed on the bus bar, such as by molding with the bus bar, and the at least one non-through clinch nut is configured to engage with at least one fastener. The at least one non-through clinch nut can include two non-through clinch nuts, and the two non-through clinch nuts can be disposed between corresponding phase lead pairs on the bus bar.

[0010] At least one bus bar seal can be disposed at an interface defined between the bus bar and the junction housing.

[0011] To address further thermal and electrical protection, a dielectric coating can be disposed at the interface between the heat sink and at least a portion of the phase bar assembly disposed within the junction housing.

[0012] The heat sink can include at least one recess, and the at least one recess is dimensioned to receive at least one fastener such that, in the mounted state, the at least one fastener is positioned below the upper surface of the heat sink.

[0013] According to one aspect, the junction assembly has an IP69K sealing rating.

[0014] Also disclosed herein is a method of providing heat dissipation for a junction assembly. The method includes disposing a heat sink in contact with at least a portion of a junction housing that supports a phase bar assembly. The method includes providing at least one heat sink seal at the interface between the heat sink and the junction housing and applying a dielectric coating to at least a portion of the interface between the heat sink and the phase bar assembly. The method can further include securing the heat sink to the junction housing and to the bus bar using at least one fastener and at least one nut.

[0015] Further embodiments are described below and in the claims.

[0016] The foregoing summary and the following detailed description will be better understood when read in conjunction with the accompanying drawings that illustrate preferred embodiments of the disclosure.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Mode for Carrying Out the Invention

[0018] In the following description, specific terms are used for convenience only and are not limiting. The terms “front,” “rear,” “upper,” and “lower” indicate directions in the referenced drawings. The terms “inwardly” and “outwardly” refer to the directions toward and away from the parts referenced in the drawings. “Axially” refers to the direction along the axis of the shaft. A reference to a list of items cited as “at least one of a, b, or c” (where a, b, and c represent the items listed) means any one of the items a, b, or c, or a combination thereof. This term includes the words specifically described above, their derivatives, and similar important words.

[0019] Referring to FIG. 1, an assembly including an e-motor 5 and a PEU 6 is disclosed. As shown in FIG. 1, a junction ンア assembly 10 is also disclosed. In one aspect, the junction ンア assembly 10 includes a plurality of phase bar assemblies 15. As shown in FIG. 1, only one visible phase bar assembly 15 is shown. In one aspect, each phase bar assembly 15 includes a phase bar body 16 that generally extends between the e-motor 5 and the PEU 6.

[0020] In one aspect, the first spacer 18 is provided on the side where the e-motor 5 is located, and the second spacer 20 is provided on the side where the PEU 6 is located. The spacers 18, 20 can be formed of a conductive metal such as copper. The spacers 18, 20 can bring about an improvement in electrical connection. Further, by using the spacers 18, 20, the ンア accessibility, assemblability, removability, and reassemblability with respect to each component of the junction assembly 10 can be improved. As shown in FIG. 2, the spacer 18 extends between the phase bar body 16 and at least one phase lead 38a. By providing a gap, for example, in the vertical direction, with the spacers 18, 20, the design of the phase bar body 16 can be improved. Also, the spacer 18 enables uniform surface contact around the boundary surface of the phase lead 38a.

[0021] The holding part 22 is provided generally for fixing the phase-bar assembly 15. As shown in FIG. 1, the holding part 22 may include a first or lower holding body 22a and a second or upper holding body 22b. A fixing element such as a dowel or other fastener can be used to fix the first holding body 22a to the second holding body 22b.

[0022] Also, a junction housing 24 that generally surrounds the holding part 22 is provided. The junction housing 24 can include a first or lower junction housing 24a and a second or upper junction housing 24b. In one aspect, the first holding body 22a, the second holding body 22b, the first junction housing 24a, and the second junction housing 24b are all fixed to each other.

[0023] In one aspect, a plurality of fasteners 26 extend between a first junction housing 24a and a second junction housing 24b. In one embodiment, these fasteners 26 can be bolts. The plurality of bolts 26 can include at least nine bolts that connect or secure the first junction housing 24a to the second junction housing 24b. These bolts 26 provide a force that compresses a junction - housing seal 29 provided in a peripheral region at the interface between the first junction housing 24a and the second junction housing 24b, as shown in FIG. 4. In one aspect, a groove 27 sized to receive the junction - housing seal 29 is formed in the lower surface of the junction housing 24b.

[0024] Fastening elements 32, 33 can be provided to fix the heat sink 30 to the bus bar 34. In one aspect, the bus bar 34 is a bus bar ring of an e - motor. In one aspect, the fastening elements include a nut 32 and a bolt 33 configured to mate with the nut 32. In one aspect, the nut 32 is a non - through clinch nut. As shown in FIG. 4, the bolt 33 extends completely through the junction housings 24a, 24b such that these bolts extend completely through both end faces of the junction housings 24a, 24b. In one aspect, the fastening elements 32, 33 include exactly two bolts 33 and exactly two nuts 32.

[0025] As best shown in FIG. 3, in one aspect, the heat sink 30 has a generally rectangular outer shape. As shown in FIG. 2, in one aspect, the height of the heat sink 30 exceeds the height of the junction housings 24a, 24b. In one aspect, the assembly disclosed herein relies entirely on the heat sink 30 for heat dissipation and does not require a cooling fluid.

[0026] The two non-through clinch nuts 32 can also be assembled to the bus bar 34 or overmolded onto the bus bar 34, and the bus bar 34 can be formed of plastic. To ensure a strong connection between the bolt 33 and the heat sink 30, a seal 35 such as an O-ring seal can be provided. In one aspect, a recess 31 sized to receive at least a portion of the bolt 33 is formed in the heat sink 30. As shown in FIG. 4, this configuration allows the fully installed bolt 33 to be fully inserted and seated within the heat sink 30.

[0027] A heat sink seal 28 can be provided at the interface between the second junction housing 24b and the heat sink 30. By fixing the bolt 33 with the non-through clinch nut 32, the heat sink seal 28 can be compressed, further ensuring the sealing function of the heat sink seal 28.

[0028] A bus bar seal 36 can be further provided around the bus bar 34 to provide a sealed interface between the bus bar 34 and the first junction housing 24a. The bus bar seal 36 can be disposed within a groove 37 formed in the bus bar 34. Other configurations or retention configurations of the bus bar seal 36 can be provided. As shown in the figure, the three seals 28, 29, 36 are in contact with the junction housings 24a, 24b.

[0029] As shown in FIG. 5, the bus bar 34 is provided with a plurality of phase leads 38a, 38b, 38c. The plurality of phase leads 38a, 38b, 38c can correspond to the U, V, W phase leads from the e-motor 5. The plurality of phase leads 38a, 38b, 38c are generally arranged at a wider interval than a known bus bar assembly, whereby the non-through clinch nut 32 can be arranged between corresponding pairs of the phase leads 38a, 38b, 38c. With this configuration, the number of bolt connections is reduced, and since the bolted joints do not directly pass through the phase leads 38a, 38b, 38c, the electrical resistance is reduced. As shown in FIG. 5, the plurality of phase leads 38a, 38b, 38c have no holes or discontinuities, but may be required in other configurations for accommodating the non-through clinch nut 32 or the bolt 33.

[0030] In one aspect, in order to provide further thermally conductive surface contact, rifling of the heat sink 30 is provided for contact with the phase bar assembly 16. One skilled in the art will understand from the present disclosure that fins, grooves, or other structures for heat dissipation can be provided on the heat sink 30 to further improve the heat dissipation capacity of the heat sink 30.

[0031] Also, the attachment of the heat sink 30 to the non-through clinch nut 32 can be configured to compress the heat sink seal 28 to further improve the overall sealing configuration of the assembly. In one aspect, the heat sink 30 includes a groove 39 sized to receive the heat sink seal 28. In one aspect, the groove 39 is formed on the lower surface of the heat sink 30.

[0032] In one aspect, a dielectric coating 40 is applied to the outer surfaces of the phase bar assembly 16 and the first spacer 18 to impart additional heat dissipation capabilities. The dielectric coating 40 can be adhered to the heat sink 30 by various manufacturing methods. In one aspect, the dielectric coating 40 has abrasion resistance so that an unintentional leakage path for the current flowing through the phase bar assembly 16 does not occur.

[0033] As shown in FIG. 2, the dielectric coating 40 can be provided at the interface between the heat sink 30 and the phase bar assembly 16 and the first spacer 18. The dielectric coating 40 can provide additional heat conduction and electrical insulation protection. The dielectric coating 40 can provide an additional heat path for the heat generated in the phase bar assembly 16 to be transferred to the heat sink 30 via the e-motor lead 38a while providing electrical insulation between the phase bar assemblies 16. As shown in FIG. 2, the heat sink 30 is in contact with at least one phase bar assembly 16.

[0034] In one aspect, the heat sink seal 28 is disposed between the heat sink 30 and the radial surface of the junction housing 24b. In one aspect, the junction housing seal 29 can also be disposed between the radial surfaces of the first junction housing 24a and the second junction housing 24b. In one aspect, the bus bar seal 36 can be disposed between the axial surface of the junction housing 24a and the bus bar 34. Those skilled in the art will understand that, based on the present disclosure, it is possible to rearrange, reposition, or modify any one or more of these seals according to a specific application.

[0035] In addition, in one aspect, the heat sink seal 28 and the junction housing seal 29 are formed as O-rings, gaskets, or other types of rubber seals having generally elliptical or circular cross-sections. In one aspect, the bus bar seal 36 can include at least one sealing body and at least one sealing leg. The exact type and configuration of the seal can vary.

[0036] In one aspect, the bus bar 34 is of a small size, and thus the non-through clinch nut 32 and the groove 37 for the bus bar seal 36 overlap each other in an axially extending plane.

[0037] Also disclosed herein is a method of providing heat dissipation for a junction assembly. The method includes disposing a heat sink 30 in contact with at least a portion of the junction housings 24, 24a, 24b that support the phase bar assembly 15. The method includes providing at least one heat sink seal 28 at the interface between the heat sink 30 and the junction housing 24b, and applying a dielectric coating 40 to at least a portion of the interface between the heat sink 30 and the phase bar assembly 15. In one aspect, the dielectric coating 40 is particularly applied at the interface between the heat sink 30 and the phase bar body 16 and the spacer 18 within the junction housing. In an additional step of the method, any one or more of the features disclosed herein may be included.

[0038] Although the embodiments have been described in detail in this way, it will be understood and will be apparent to those skilled in the art that many physical changes can be made without changing the concepts and principles of the invention embodied in the embodiments, only some of which are illustrated in the detailed description of the disclosure.

[0039] Moreover, numerous embodiments incorporating only a part of the preferred embodiments are possible, and it should be understood that with respect to these parts, the concepts and principles of the present invention embodied in the embodiments are not changed.

[0040] Accordingly, all of the present embodiment and the optional configurations are to be regarded as illustrative and / or explanatory in all respects and not restrictive, and the scope of the present disclosure is indicated not by the foregoing specification but by the appended claims, and accordingly, all alternative embodiments and modifications to the present embodiment that fall within the scope of the purpose of the claims and their equivalents are to be included in the claims.

Description of Reference Numerals

[0041] 5 e-motor 6 PEU 10 Junction Assembly 15 Phase Bar Assembly 16 Phase Bar Body 18 e-motor Side Spacer 20 PEU Side Spacer 22, 22a, 22b Holding Portion 24, 24a, 24b Junction Housing 26 Fastener 27 Junction Housing Groove 28 Heat Sink Seal 29 Junction Housing Seal 30 Heat Sink 31 Recess 32 Non-Penetrating Clinch Nut 33 Bolt 34 Bus Bar 35 O-ring Seal 36 Bus Bar Seal 37 Bus Bar Groove 38a, 38b, 38c Multiple Phase Leads 39 Groove 40 Dielectric Coating

Claims

1. A junction assembly, a junction housing configured such that a holding part (22) supports a phase bar assembly, a heat sink in contact with at least a part of the junction housing, a bus bar disposed adjacent to the junction housing, at least one fastener attaching the junction housing, the heat sink, and the bus bar to each other, at least one heat sink seal provided on an interface defined between the heat sink and the junction housing, and comprising a junction assembly.

2. The junction assembly according to claim 1, wherein the junction housing includes a first junction housing and a second junction housing, and a junction housing seal is disposed between the first junction housing and the second junction housing.

3. The junction assembly according to claim 1, further comprising at least one non-through clinch nut disposed on the bus bar, the at least one non-through clinch nut being configured to engage with the at least one fastener.

4. The junction assembly according to claim 3, wherein the at least one non-through clinch nut includes two non-through clinch nuts, and the two non-through clinch nuts are disposed between corresponding phase leads of the bus bar.

5. The junction assembly according to claim 4, wherein the two non-through clinch nuts are molded with the bus bar.

6. The junction assembly according to claim 1, further comprising at least one bus bar seal disposed on a boundary surface defined between the bus bar and the junction housing.

7. The junction assembly according to claim 1, further comprising a dielectric coating disposed on a boundary surface between the heat sink and at least a part of a phase bar assembly disposed within the junction housing.

8. The junction assembly according to claim 1, further comprising an O-ring seal disposed on a boundary surface defined around the at least one fastener and around the heat sink.

9. The heat sink includes at least one recess, and the at least one recess is dimensioned to receive the at least one fastener such that, in the mounted state, the at least one fastener is positioned below the upper surface of the heat sink. The junction assembly according to claim 1.

10. The junction assembly according to claim 1, wherein the at least one fastener extends between opposite end faces of the junction housing.

11. The junction assembly according to claim 1, wherein the bottom surface of the heat sink is in contact with at least one phase bar body disposed inside the junction housing.

12. The junction assembly according to claim 1, wherein the at least one fastener consists of two fasteners.

13. A junction assembly, A junction housing in which a holding part (22) is configured to support a phase bar assembly, including a first junction housing, a second junction housing, and a junction housing seal disposed between the first junction housing and the second junction housing. A heat sink disposed in direct contact with a first side of the junction housing, and at least one heat sink seal disposed in contact with the heat sink and the junction housing. A bus bar disposed in direct contact with a second side of the junction housing, and at least one bus bar seal disposed between the bus bar and the junction housing. At least one nut molded with the bus bar and at least one fastener configured to engage in a mating engagement with the at least one nut, the at least one fastener being configured to attach the junction housing, the heat sink, and the bus bar to each other. A junction assembly comprising the above.

14. The junction assembly according to claim 13, further comprising a dielectric coating disposed at an interface between the heat sink and at least a portion of a phase bar assembly disposed within the junction housing.

15. A method for providing heat dissipation of a junction assembly, the method comprising: Disposing a heat sink in contact with at least a portion of a junction housing in which a holding part (22) is configured to support a phase bar assembly; Providing at least one heat sink seal at an interface between the heat sink and the junction housing; Applying a dielectric coating to at least a portion of the interface between the heat sink and the phase bar assembly; A method comprising. **Claim 16** The method according to claim 15, further comprising fixing the heat sink to the junction housing and to the bus bar using at least one fastener and at least one nut. **Claim 17** The method according to claim 16, wherein the at least one nut is a non-through clinch nut molded with the bus bar. **Claim 18** The method according to claim 17, wherein the at least one nut is disposed between two phase leads in the bus bar. **Claim 19** The method according to claim 15, wherein the junction housing includes a first junction housing and a second junction housing, and the method further comprises disposing at least one junction housing seal between the first junction housing and the second junction housing.

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