Electronic assembly with a waterproof connection

Abstract

An electronic assembly (5) comprising electronic elements arranged in an electronic housing (51) and a connecting piece (52) configured to connect the electronic assembly (5) to a motor assembly (10), the electronic housing (51) having an internal compartment (53) independent of the rest of the electronic housing (51) in terms of sealing, the connecting piece being disposed at least partially in this internal compartment (53). Figure for the abbreviation: Fig. 2.

Description

Title of the invention: Electronic assembly comprising a waterproof connection

[0001] The present invention relates to an electronic assembly of an electric machine of a motor vehicle, for example a rotating electric machine, and more particularly an electronic assembly comprising at least one power module and electronic elements.

[0002] The invention also relates to an electrical machine comprising such an electronic assembly.

[0003] More particularly, the invention finds applications in the field of rotating electrical machines such as generators, alternators, alternator-starters, whose voltages are between 10 and 60V, and for example are equal to or greater than 48V.

[0004] Typically, the electric machine comprises an electronic assembly connected to the machine's motor assembly. The connection is made via the bus bars of each assembly. The two bus bars are connected to each other by a connecting piece.

[0005] One disadvantage of this connection system is that it is necessary to seal the connection piece.

[0006] This implies that the electronic assembly cannot be decoupled from the assembly motor without losing sealing, and involves long connections that could be damaged during transport.

[0007] The present invention therefore aims to overcome one or more of the drawbacks of prior art devices by proposing an electronic assembly whose connections are watertight.

[0008] To this end, the present invention proposes an electronic assembly comprising electronic elements arranged in an electronic housing and a connection piece configured to connect the electronic assembly to a motor assembly,

[0009] the electronic housing comprising an internal housing independent of the rest of the electronic housing in terms of sealing, the connection piece being disposed at least in part in this internal housing.

[0010] Such a configuration allows the electronic assembly to be decoupled from the motor assembly without losing its sealing, and without involving long connections that could be damaged during transport.

[0011] The electronic assembly is thus independent of the rest of the electrical machine, and sealed.

[0012] According to one embodiment of the invention, the connecting piece is disposed entirely in the internal housing.

[0013] According to one embodiment of the invention, the connection piece is disposed at the level of a first opening of the electronic housing.

[0014] According to one embodiment of the invention, the first opening leads into the internal housing.

[0015] According to one embodiment of the invention, the connecting piece is screwed onto an internal surface of the housing.

[0016] According to one embodiment of the invention, the screwing is carried out via a second opening formed in the housing, the second opening leading to the outside of the electronic housing.

[0017] According to one embodiment of the invention, the connecting piece includes a sealing system enabling the electronic assembly to avoid being contaminated by dust.

[0018] According to one embodiment of the invention, the second opening of the housing includes a removable closing piece comprising a seal to ensure the sealing of the internal housing when it is closed.

[0019] Other objects, features and advantages of the invention will be better understood and will become more apparent upon reading the description given below, with reference to the accompanying figures, given by way of example and in which:

[0020] - Fig. 1 is a schematic cross-sectional representation of an electrical machine according to one embodiment of the invention,

[0021] - [Fig.2] is a schematic cross-sectional representation of part of a mode of construction of an electrical machine according to the invention,

[0022] - [Fig. 3] is a cross-sectional view of part of the electronic assembly according to the invention.

[0023] Figure 1 illustrates a rotating electrical machine 1 comprising a fixed, polyphase stator 11 surrounding a rotating rotor 12 mounted on a shaft 13 extending along an axis of rotation X. The axis of rotation X is defined as the axis of the rotating electrical machine 1. These elements form the electric motor assembly 10. The electrical machine 1 has an internal space that houses the various functional elements of the machine. The machine has a fixed, metallic casing 14, shown in the following figures, which defines at least part of the internal space of the motor assembly 10 of the electrical machine 1.

[0024] According to one embodiment, the machine 1 includes an electronic assembly 5 comprising at least one electronic power and control module, also called a power inverter, for supplying a polyphase current system to the stator 11.

[0025] According to one embodiment, the electronic assembly 5 comprises power components, as well as an electronic control circuit for said power components. These power components are, in particular, switching elements, such as low thermal resistance transistors such as MOSFETs. These switching elements are, for example, based on gallium nitride (GaN). The electronic assembly 5 also comprises a circuit. All of these components are located in the electronic package 51.

[0026] According to one embodiment, the electronic assembly 5 also includes a plurality of input pins 56 for connecting these switching elements to the stator 11 of the electric machine. These input pins 56 extend only and entirely within the internal space of the electronic module.

[0027] According to one embodiment, the electronic assembly 5 is arranged on one side of an axial end of the electric machine 1. The motor assembly 10 and the electronic assembly 5 are therefore axially successive.

[0028] According to an illustrated embodiment [Fig.2], the electric machine 1 is in a so-called "backpack" configuration, the electronic assembly 5 is carried radially by the electric motor assembly 10. There is a radial plane which passes through both the electric motor assembly 10 and the electronic assembly 5.

[0029] According to one embodiment, the electrical machine 1 can be cooled by oil or by water. The electronic assembly 5 can be water-cooled. The electronic assembly 5 includes a heat sink to cool its internal space, which contains the power components and which heat up when the assembly is operating.

[0030] In the context of the invention, the electronic housing 51 comprises an internal housing 53, illustrated in [Fig. 2], which is independent of the rest of the electronic housing 51 in terms of sealing. More precisely, this housing 53 is open to the outside of the electronic housing 51, but sealed against the rest of the interior of the electronic housing 51. This internal housing 53 forms an interconnection cavity.

[0031] According to one embodiment of the invention, a connecting piece 52 for connecting the electronic assembly 5 to the motor assembly 10 is disposed at least in part in this housing 53, at the level of a first opening 61 of the electronic housing 51.

[0032] According to one relation mode of the invention, the connecting piece 52 is disposed entirely in the internal housing 53.

[0033] The first opening leads into the internal housing 53. The connecting piece 52 is screwed onto an internal surface of the housing 53. The internal surface of the housing is the one in contact with the remaining portion 58 of the interior of the electronic housing 51. The remaining portion 58 of the electronic housing 51 is the part of the housing that is not the internal housing 53.

[0034] This part 52 is screwed into the housing so as to be able to communicate with the rest 58 of the interior of the electronic housing 51. Screwing is made possible by a second opening 71 formed in the housing 53, this second opening 71 leading to the outside of the electronic housing 51. The outside of the housing 51 is considered in contrast to the inside, the electronic components being arranged inside the housing 51.

[0035] The connection between the connecting part 52 and the pins 56 is made through a closing system 62 equipped with a sealing element 63 allowing the electronic assembly 5 to avoid being contaminated by dust caused by screwing.

[0036] According to one embodiment of the invention, the sealing element 63 is formed by a seal 63 disposed between the connecting piece 52 and the edges of the first 61 opening of the electronic housing 51.

[0037] During screwing, the sealing element is compressed between the connecting piece and the edges of the first 61 opening of the electronic housing 51, which makes it possible to achieve sealing of the inside of the electronic housing 51.

[0038] The housing 53 thus makes it possible to protect the inside of the electronic housing 51 from screwing dust.

[0039] As illustrated [Fig. 3], the second opening 71 of the housing 53 includes a removable closing piece 72. This closing piece 72 includes a seal 73 for ensuring the housing is watertight when closed. The seal is positioned so as to be located between a surface of the cover and the surface of the edge of the opening.

[0040] According to one embodiment of the invention, the connection piece 52 is a bus bar allowing the electronic assembly 5 and the motor assembly 10 to be connected.

[0041] According to one embodiment of the invention, the electric machine 1 has both the function of an alternator and an electric motor. More specifically, the electric machine 10 is integrated into a motor vehicle comprising an internal combustion engine (not shown) having an output shaft to which the electric machine 130 is connected by a belt (not shown). The internal combustion engine is intended to drive the wheels of the motor vehicle via its output shaft. Thus, when operating as an alternator, the electric machine supplies electrical energy to the power supply 2 from the rotation of the output shaft. When operating as an electric motor, the electric machine drives the output shaft (in addition to or instead of the internal combustion engine).The electrical machine 10 is, for example, located in a gearbox or in a clutch of the motor vehicle or in place of the alternator.

[0042] According to one embodiment, the power of machine 1 is between 10kW and 50kW.

[0043] According to one embodiment, the electric machine 1 advantageously has an operating voltage of less than 60 Volts, and preferably 48 Volts. Typically, the torque supplied by the electric machine is between 50 N.m and 150 N.m.

[0044] The invention also relates to the use of the electric machine 1 according to the invention in a thermal, electric or hybrid vehicle

[0045] The scope of the present invention is not limited to the details given above and allows for embodiments in many other specific forms without departing from the field of application of the invention. Therefore, the present embodiments should be considered by way of illustration and may be modified without, however, departing from the scope defined by the claims.

Claims

Demands

1. Electronic assembly (5) comprising electronic elements arranged in an electronic housing (51) and a connecting piece (52) configured to connect the electronic assembly (5) to a motor assembly (10), the electronic housing (51) comprising an internal housing (53) independent of the rest of the electronic housing (51) in terms of sealing, the connecting piece being disposed at least in part in this internal housing (53), characterized in that the connecting piece is a bus bar (52) disposed entirely in the internal housing (53) and comprises a sealing system (62) enabling the electronic assembly (5) to avoid being contaminated by dust.

2. Electronic assembly (5) according to claim 1, wherein the connecting piece (52) is disposed at a first opening (61) of the electronic housing (51).

3. Electronic assembly (5) according to any one of claims 1 to 2, wherein the first opening (61) leads into the internal housing (53).

4. Electronic assembly (5) according to any one of claims 1 to 3, wherein the connecting piece (52) is screwed onto an internal surface of the housing (53).

5. Electronic assembly (5) according to claim 4, wherein the screwing is carried out via a second (71) opening formed in the housing (53), the second (71) opening leading outwards from the outside of the electronic housing (51).

6. Electronic assembly (5) according to any one of claims 5 or 6 when it depends on claim 6, wherein the second (71) opening of the housing (53) includes a removable closing piece (72) having a seal (73) to ensure the sealing of the internal housing (53) when closed.

7. Electrical machine (1) comprising an electronic assembly (5) according to any one of claims 1 to 6.

8. Use of the electronic assembly (5) according to any one of claims 1 to 6 in a motor vehicle.

Images