JP2023553306A - electric machine - Google Patents

Abstract

An electric machine for vehicle air conditioning is provided. The electric machine includes a first housing, a second housing, a sealing element, and a plurality of tensioning members. The first housing having a first mating surface is adapted to house an electric motor and the second housing having a second mating surface is adapted to house an inverter assembly. Further, the first mating surface and the second mating surface are complementary and face each other. The sealing element is disposed between the first mating surface and the second mating surface and is adapted to mate the second housing with the first housing. Furthermore, the plurality of tension applying members are provided in holes formed in the first mating surface and the second mating surface when the first housing and the second housing are coupled. [Selection diagram] Figure 6

Description

The present invention relates to an electric machine, and more particularly to a connection between a motor housing and an inverter housing of the electric machine to reduce leakage of electromagnetic noise from the casing of the electric machine.

Generally, the air conditioning circuit of a vehicle is equipped with an electric machine, specifically an electric compressor. Electric compressors include a compression unit for compressing refrigerant, an electric motor that drives the compression unit, and an inverter assembly that drives the electric motor in a controlled manner. Furthermore, respective housings are provided to enclose each part of the electric compressor, and the housings are mechanically coupled to each other by various fasteners. In one embodiment, a motor housing is provided to enclose the electric motor and an inverter housing is provided to enclose the inverter assembly. An electric motor in the compressor allows refrigerant to be drawn into the compression unit through an inlet port formed in the motor housing, and the refrigerant circulates through the motor housing to cool the electric motor. It is supposed to be done. Generally, a motor housing is made of aluminum and has a cylindrical shape and has openings at both ends. Additionally, refrigerant enters the compression unit, is compressed, and exits the electric compressor through a discharge port formed in a rear cover coupled to one end of the motor housing. The other end of the motor housing is an insertion port for the electric motor and is coupled to the inverter housing. Conventionally, the mating portions of each housing are sealed with a gasket to prevent refrigerant leakage. Generally, the gasket disposed between the motor housing and the inverter housing has three layers. For example, a base plate made of a metal material is used as the first layer, and rubber coated on both sides of the base plate forms the second and third layers. The inverter housing also includes high voltage (HV) connector terminals and low voltage (LV) connector terminals. Electromagnetic noise is typically generated by the moving parts of an electric motor within the motor housing. This electromagnetic noise can propagate from the motor housing to the inverter housing if the gasket is a rubber-coated metal gasket. Additionally, this electromagnetic noise propagated from the motor housing can interact with the HV and LV connector terminals. Such interaction of electromagnetic noise with the connector terminals can penetrate into the inverter housing and cause malfunction of the control circuitry enclosed therein.

Therefore, there is a need for an electric machine that includes a mechanism to avoid leakage of electromagnetic noise from its housing. There is also a need for a connection formed between a motor housing and an inverter housing of an electrical machine that reduces leakage paths of electromagnetic noise by connecting it to ground. Additionally, there is a need for an electrical machine with a mechanism to protect the inverter circuit from electromagnetic noise interference.

In the description herein, multiple elements or parameters may be indexed, such as a first element, a second element, etc. In this case, unless otherwise stated, this indexing is only for distinguishing and naming similar but not identical elements. No concept of priority should be inferred from such indexing, as these terms may be interchanged without departing from the invention. Furthermore, this indexing does not imply any order in the installation or use of the elements of the invention.

From the foregoing, one embodiment of the invention herein provides an electric machine, specifically an electric compressor for vehicle air conditioning. The electric machine includes a first housing, a second housing, a sealing element, and a plurality of tensioning members. The first housing having a first mating surface is adapted to house an electric motor and the second housing having a second mating surface is adapted to house an inverter assembly. Further, the first mating surface and the second mating surface are complementary and face each other. The sealing element is disposed between the first mating surface and the second mating surface, and the second housing is adapted to mate with the first housing. Furthermore, the plurality of tension applying members are provided in holes formed in the first mating surface and the second mating surface when the first housing and the second housing are coupled.

Further, the sealing element has a hole for passing the tensioning member that is aligned with the hole formed in the first mating surface and the second mating surface.

In one embodiment, the second housing includes an extension extending radially outward therefrom and at least one of the first and second connectors disposed on a sidewall of the extension.

In one embodiment, the plurality of tension applying members are disposed at a peripheral edge of the second mating surface in a region corresponding to at least one of the first and second connectors.

The electric machine includes a plurality of bosses formed on a peripheral edge of the first mating surface and a peripheral edge of the second mating surface on sides corresponding to at least one of the first and second connectors. The boss further includes the hole formed in the boss.

In one embodiment, the holes are formed in the first mating surface and the second mating surface at a predetermined distance apart.

In one embodiment, at least one of the distances between adjacent holes formed in the first mating surface and the second mating surface is less than 30 mm.

Furthermore, the sealing element is a metal gasket coated with rubber.

Furthermore, the plurality of tension applying members are spring pins.

In another embodiment, the electric machine further includes at least two pins formed in the second housing to align the first housing with the second housing.

Other features, details and advantages of the invention can be deduced from the following description of the invention. BRIEF DESCRIPTION OF THE DRAWINGS A more complete understanding of the present invention and its many attendant advantages will be readily attained as the following detailed description is read in conjunction with the accompanying drawings.

1 is a block diagram of an electric machine according to an embodiment of the invention. FIG. 2 is a schematic diagram of a first housing of the electric machine of FIG. 1; FIG. 2 is a sectional view along the longitudinal axis of the electrical machine of FIG. 1; FIG. 2 is a schematic view in a plane perpendicular to the longitudinal axis of the second housing of the electric machine of FIG. 1; FIG. 2 is an exploded view of a second housing containing an inverter assembly of the electric machine of FIG. 1; FIG. 2 is an exploded view of the electric machine of FIG. 1; FIG. 2 is an enlarged cross-sectional view of one of the plurality of tensioning members coupled between the first and second housings of FIG. 1; FIG.

It should be noted that each figure discloses the invention in sufficient detail to carry it into practice and to help more clearly define the invention if necessary. However, the invention should not be limited to the embodiments disclosed herein.

The present invention relates to an electric machine, and more particularly to an electric compressor installed in an air conditioning circuit of a vehicle. Generally, an electric compressor includes a motor housing in which an electric motor is provided and an inverter housing in which an inverter assembly is provided. The motor housing and the inverter housing are coupled to each other to enable a connection between the electric motor and the inverter. Furthermore, the electric motor is connected to a compression unit that compresses the refrigerant flowing inside. A rubber-coated metal gasket is provided between the motor housing and the inverter housing to enable a fluid-tight connection between the motor housing and the inverter housing. Such rubber coatings on the gaskets propagate electromagnetic noise generated by electric motors located within the motor housing. Therefore, such gaskets can propagate electromagnetic noise to the inverter assembly, thereby causing malfunction of the inverter assembly. To avoid this situation, allow for a physical connection between the inverter housing and the motor housing. Such a physical connection interacts with the outer casing of the electrical machine, which is connected to vehicle ground. Therefore, intrusion of electromagnetic noise into the inverter housing is restricted. A further explanation of the arrangement and function of the physical connections described above is provided with reference to the following figures.

FIG. 1 shows a block diagram of an electric machine 100 according to one embodiment of the invention. In this embodiment, the electric machine 100 is an electric compressor, specifically, an electric compressor 100 integrated with an inverter. Electric machine 100 is installed in the refrigerant circuit of a vehicle. Generally, electric machine 100 is installed in a refrigerant circuit of a vehicle and compresses refrigerant flowing therethrough. Electric machine 100 includes a first housing 110 adapted to house an electric motor 112, a second housing 120 adapted to house an inverter assembly 122, and a compression unit 132. and an adapted third housing 130. Further, the first housing 110, the second housing 120 and the third housing 130 are secured together by fastening means (not shown) such as bolts to form a housing of the electric machine 100. In one embodiment, first housing 110, second housing 120, and third housing 130 are formed of metal, specifically die-cast aluminum.

An electric motor 112 provided in the first housing 110 includes a stator and a rotor (not shown in FIG. 1). Further, a rotating shaft 134 is connected to the rotor, and the rotating shaft 134 extends into the third housing 130 and is coupled to the compression unit 132 . A first housing 110, which is a motor housing, is formed in a cylindrical shape with openings at both ends for accommodating an electric motor 112. Furthermore, one end of the first housing 110 is coupled to a third housing 130 that includes a compression unit 132. The other end of the first housing 110 provides an insertion port for an electric motor 112 and is coupled to a second housing 120 that includes an inverter assembly 122 . When electric motor 112 is energized, rotation shaft 134 drives compression unit 132 provided in third housing 130 .

The compression unit 132 provided in the third housing 130 includes a fixed scroll and an orbiting scroll for compressing the refrigerant flowing therein. In one embodiment, the fixed scroll is fixedly and integrally formed with the third housing 130. The orbiting scroll is rotatably connected to an eccentric pin formed by a rotating shaft 134 extending from the first housing 110. The orbiting scroll is adapted to compress refrigerant in a compression space defined between the fixed scroll and the orbiting scroll when the rotating shaft 134 is rotated by the electric motor 112. That is, the refrigerant in the compression space is compressed by the orbiting motion of the orbiting scroll relative to the fixed scroll. Furthermore, a suction port 136 for sucking refrigerant into the electric machine 100 is formed integrally with the first housing 110 . Refrigerant drawn through the suction port 136 of the first housing 110 flows past the electric motor 112 to cool or absorb heat generated by the electric motor 112 and into the third housing 130 for the compression process. You can enter. The compressed refrigerant then exits the electrical machine 100 through a discharge port 150 integrally formed with the third housing 130.

An inverter assembly 122 housed in a second inverter housing 120 is adapted to drive the electric motor 112 in a controlled manner. Inverter assembly 122 includes a plurality of electronic components mounted on a circuit board to perform the necessary operations. Electric power is supplied to the circuit board from an external power source such as a vehicle battery. The circuit board is shown in FIG. Additionally, a hermetic terminal 142 is provided on the end wall of the second housing 120 and is adapted to couple with the electric motor 112. Inverter assembly 122 generates controlled inputs for electric motor 112 and routes such inputs to electric motor 112 via hermetic terminals 142 . Additionally, the input generated at inverter assembly 122 may control the speed of electric motor 112.

FIG. 2 shows a schematic diagram of the first housing 110 of the electric machine 100 of FIG. Electric motor 112 is not shown in FIG. In one embodiment, the first housing 110 includes an annular wall 208 extending a distance so that it is formed as a cylinder. Additionally, first housing 110 includes a first mating surface 202 defined at its A-side longitudinal end. In one embodiment, the first housing 110 is hollow and cylindrical, and its inner circumferential surface defines an opening on the A side. Furthermore, the first housing 110 has openings on both sides for coupling with the second housing 120 and the third housing 130, respectively. In one embodiment, the opening formed on the A side of the first housing 110 is adapted to line up with the second housing 120, and the opening formed on the B side of the first housing 110 is adapted to align with the second housing 120. It is lined up with the housing 130 of No. 3. Furthermore, the third housing 130 is mechanically coupled to the opening defined on the B side of the first housing 110 by any connecting means. The connecting means may be a plurality of threads and bolts. In one embodiment, the electric motor 112 is inserted into the first housing 110 through an opening defined on the A side thereof.

Additionally, the suction port 136 projects from the annular wall 208 of the first housing 110, as shown in FIG. In one embodiment, the first housing 110 may further include an attachment mechanism on its outer surface that allows the electric machine 100 to be attached to a vehicle body.

Further, at least two positioning holes 210A, 210B are provided on the outer and/or inner periphery of the first mating surface 202 at a predetermined distance apart. These holes are for receiving any connection means such as locating pins, thereby allowing efficient positioning between the first housing 110 and the second housing 120. Specifically, the positioning holes 210A and 210B are provided at opposing positions on the periphery of the first mating surface 202 with the central axis of the first housing 110 interposed therebetween.

First housing 110 further includes a plurality of holes 204A-D formed in first mating surface 202 at a predetermined distance apart. In one embodiment, a plurality of holes 204A-D are formed in the periphery of first mating surface 202. According to this embodiment, as shown in FIG. 2, a plurality of bosses 206A-D are provided on the outer peripheral surface of the opening. That is, the plurality of bosses 206A-D are formed on the outer surface of the first housing 110 around the periphery of the opening defined in the first housing 110. Further, a plurality of holes 204A-D are formed in these plurality of bosses 206A-D.

FIG. 3 shows a cross-sectional view of the electrical machine 100 of FIG. 1 in a plane perpendicular to the longitudinal axis of the electrical machine 100. Second housing 120 includes a base plate 302 and a peripheral wall 306 extending from an outer edge of base plate 302 to define a space for receiving inverter assembly 122 . In one embodiment, the base plate 302 is contoured to accommodate the electronic components 320 of the inverter assembly 122.

Further, as shown in FIG. 3, second housing 120 includes an extension portion 316 that extends radially outwardly from the outer diameter of first housing 110. As shown in FIG. In one embodiment, the base plate 302 of the second housing 120 includes a lower portion 308A that is complementary to the opening provided in the first housing 110 and an upper portion 308B that forms the sidewall 304 of the extension portion 316. Additionally, the lower portion 308A of the second housing 120 is annular in shape and adapted to mate with the first housing 110.

In one embodiment, the hermetic terminal 142 is provided on the lower portion 308A of the base plate 302 of the second housing 120, as shown in FIGS. 1 and 4. Inverter assembly 122 and electric motor 112 are electrically connected via hermetic terminals 142 . The lower portion 308A of the second housing 120 includes a second mating surface 310 that is complementary to and opposite the first mating surface 202 of the first housing 110.

Further, second mating surface 310 includes a plurality of holes 312A-D provided thereon. In one embodiment, the plurality of holes 312A-D formed in the second mating surface 310 are complementary to the plurality of holes 204A-D formed in the first mating surface 202. Additionally, a plurality of bosses 314A-D are provided on the second mating surface 310. In one embodiment, a plurality of bosses 314A-D are provided at the periphery of second mating surface 310.

As shown in FIGS. 3 and 4, second housing 120 further includes at least two connectors 318A-B on sidewall 304 of extension portion 316. As shown in FIGS. The two connectors 318A-B include at least a first connector 318A and a second connector 318B for providing electrical energy and signals to the inverter assembly 122. In one embodiment, the first connector 318A is a high voltage terminal and the second connector 318B is a low voltage terminal.

As shown in FIGS. 3 and 5, inverter assembly 122 further includes a plurality of electronic components 320 attached to circuit board 138 for control operations. As shown in FIG. 5, circuit board 138 is positioned within the receiving space of the inverter assembly and secured to base plate 302 with a plurality of bolts/screws 228. First connector 318A and second connector 318B are electrically connected to electronic components 320 provided on circuit board 138 of inverter assembly 122 via bus bars and/or wires. In one example, high voltage terminal 318A provides high voltage to an inverter designed with electronic component 320. Such an inverter converts high voltage DC power into three-phase AC power and transmits the power to an electric motor 112 provided in the first housing 110. Additionally, low voltage terminal 318B provides low voltage DC power to a control unit designed using electronic component 320. The control unit controls the electric motor 112, such as the rotation speed and number of rotations of the rotor, and turning the electric motor 112 on and off.

In a preferred embodiment, the plurality of bosses 206A-D, 314A-D are arranged around the periphery of the first mating surface 202 of the first housing 110 and the periphery of the second mating surface 310 of the second housing 120. Formed on the side corresponding to 318A-B. In one embodiment, bosses 206A-D formed on first mating surface 202 are complementary to bosses 314A-D formed on second mating surface 310.

FIG. 6 is an exploded view of the electrical machine 100 of FIG. 1 showing the connection between the first housing 110 and the second housing 120. As mentioned above, the first mating surface 202 of the first housing 110 is complementary to and adapted to mate with the second mating surface 310 of the second housing 120. Furthermore, a sealing element 402 is provided between the first mating surface 202 and the second mating surface 310. Sealing element 402 constitutes a fluid-tight connection between first housing 110 and second housing 120. In one embodiment, sealing element 402 is a gasket comprised of three layers. Among these three layers, for example, the first layer is made of a metallic material, and the rubber coated on both sides of the first layer forms the second and third layers. Sealing element 402 contacts first mating surface 202 and second mating surface 310 when first housing 110 and second housing 120 are coupled.

Sealing element 402 further includes holes 404A-D formed in its periphery. In one embodiment, the holes 404A-D are aligned with holes 204A-D, 312A-D formed in the first mating surface 202 of the first housing 110 and the second mating surface 310 of the second housing 120. lined up in

Electric machine 100 further includes a plurality of tensioning members 406A-D. The plurality of tension applying members 406A-D are inserted into holes 204A-D, 312A-D formed in the first mating surface 202 and the second mating surface 310 when the first housing 110 and the second housing 120 are coupled. It is set in the. In one embodiment, the plurality of tensioning members 406A-D are spring pins. Furthermore, the plurality of tension applying members 406A-D are made of metal material.

In one embodiment, the plurality of tensioning members 406A-D are disposed around the periphery of the second mating surface 310 in an area corresponding to at least one of the first connector 318A and the second connector 318B. . As shown in FIGS. 4 and 6, holes 312A-D and tensioning members 406A-D inserted therein are connected to connectors 318A-B and the interior of second mating surface 310 where electromagnetic noise is generated. It is placed in the area between.

In another embodiment, the plurality of tensioning members 406A-D are adapted to elastically deform along their radial direction, and this deformation is such that the plurality of tensioning members 406A-D and when inserted into the holes 204A-D, 312A-D formed in the second mating surface 310. In one embodiment, the outer diameter of the plurality of tensioning members 406A-D is equal to or greater than the inner diameter of the holes 204A-D, 312A-D. When the diameters of the holes 204A-D, 312A-D are the same as the diameters of the plurality of tension applying members 406A-D, the plurality of tension applying members 406A-D can be easily inserted into the holes 204A-D, 312A-D. The plurality of tensioning members 406A-D need to be elastically deformed radially along them so as to be able to do so. In this example, one end of a plurality of tensioning members 406A-D is inserted into holes 312A-D formed in second mating surface 310. Thereafter, the plurality of tension applying members 406A to D provided in the holes 312A to D of the second mating surface 310 are passed through the holes 404A to D formed in the sealing member 402 to close the sealing member 402. Disposed on the second mating surface 310 of the second housing 120 . Further, when coupling the first housing 110 to the second housing 120 to form the casing of the electric machine 100, the other ends of the plurality of tension applying members 406A-D are connected to the first mating surface 202. into the holes 204A to 204D formed in the. When a plurality of tension applying members 406A to 406D are provided between the first housing 110 and the second housing 120, the tension applying members 406A to 406D cause the first housing 110 and the second housing 120 to physical contact between them is possible. Furthermore, the main body of the second housing 120 is connected to the ground of the vehicle. When the plurality of tension applying members 406A-D enable physical contact between the first housing 110 and the second housing 120, electromagnetic noise generated by the electric motor 112 of the first housing 110 is transmitted to the second housing 110. is connected to ground via the housing 120 of.

Providing the plurality of tension applying members 406A to 406D in areas corresponding to the connectors 318A to 318B between the first housing 110 and the second housing 120 prevents electromagnetic noise from propagating to the connectors 318A to 318B. can be prevented. This prevents interaction between electronic components 320 provided in inverter assembly 122 and electromagnetic noise.

FIG. 7 shows an enlarged cross-sectional view of one of the plurality of tensioning members 406A-D secured between the first housing 110 and the second housing 120. Additionally, the plurality of tensioning members 406A-D are made of metallic materials with high electrical conductivity and EMC/EMI shielding properties, such as copper, iron, steel, and aluminum. In one embodiment, tension application members 406A-D each include a cylindrically extending pin body with a longitudinal slit formed therein. Furthermore, both ends of the pin body are provided with sloped surfaces. This surface allows for easy insertion of tensioning members 406A-D into holes 204A-D, 312A-D when first housing 110 and second housing 120 are assembled. In one embodiment, one of the distances between adjacent tensioning members 406A-D of the plurality of tensioning members 406A-D is less than 30 mm. In another embodiment, as shown in FIG. 6, at least two solid metal pins 408 are inserted into locating holes 410A and 410B formed in second housing 120. This is to arrange the first housing 110 and the second housing 120 in line. Furthermore, the positioning holes 410A-B formed in the second housing 120 are complementary to the positioning holes 210A-B formed in the first housing 110.

As noted above, the outer diameter of the plurality of tensioning members 406A-D is equal to or greater than the inner diameter of the holes 204A-D, 312A-D. As a result, the coefficient of friction between the outer barrel of the plurality of tensioning members 406A-D and the inner wall of the holes 204A-D, 312A-D may be high, thereby causing the plurality of tensioning members 406A-D are held inside the holes 204A-D, 312A-D. To insert a plurality of tension applying members 406A-D into respective holes 204A-D, 312A-D provided in first housing 110 and second housing 120, both ends of the members are inserted into the holes. The member is deformed along its radial direction so that it can be inserted. In one embodiment, tensioning members 406A-D each have a length of 14 mm. In one embodiment, the portions of the pin bodies of the plurality of tension application members 406A-D that are inserted into the holes 204A-D provided in the first housing 110 are inserted into the holes 312A-D provided in the second member 120. It is larger than the part inserted into D.

All the above-mentioned embodiments are only for illustrating the invention, and there may be more embodiments and combinations thereof. Therefore, the invention should not be limited only to the embodiments described above.

100 Electric machine 110 First housing 112 Electric motor 120 Second housing 122 Inverter assembly 130 Third housing 132 Compression unit 134 Rotating shaft 136 Suction port 138 Circuit board 142 Airtight terminal 150 Discharge port 208 Annular shape of first housing Wall of 202 First mating surface of first housing 204A-D Hole of first mating surface 206A-D Boss of first mating surface 210A,B Positioning hole of first housing 228 Bolt/screw 302 Second Base plate of the housing 304 Side wall of the extension 306 Peripheral wall of the second housing 308A Lower portion of the base plate 308B Upper portion of the base plate 310 Second mating surface of the second housing 312A-D Holes in the second mating surface 314A-D Second mating surface boss 316 Second housing extension 318A First connector 318B Second connector 320 Electronic component 402 Sealing element 404A-D Sealing element hole 406A-D Tension application member 408 Pin 410A, B Positioning hole of second housing

Claims (10)

An electric machine (100),
a first housing (110) having a first mating surface (202) and adapted to house an electric motor (112);
a second housing (120) having a second mating surface (310) and adapted to house an inverter assembly (122), the first mating surface (202) and the second housing (120) having a second mating surface (310); a second housing (120) having complementary mating surfaces (310) and facing each other;
a sealing element (402) disposed between the first mating surface (202) and the second mating surface (310), wherein the second housing (120) is connected to the first housing; (110); a sealing element (402) adapted to be coupled with (110);
When the first housing (110) and the second housing (120) are coupled, holes (204A-D, a plurality of tension application members (406A to D) provided in the tension application members (312A to D);
An electric machine (100) comprising: the tension, wherein the sealing element (402) is aligned with the holes (204A-D, 312A-D) formed in the first mating surface (202) and the second mating surface (310); The electric machine (100) of claim 1, having holes (404A-D) for passing application members (406A-D). The second housing (120) includes an extension (316) extending radially outwardly therewith and first and second connectors (318A) provided on the sidewalls (304) of the extension (316). , 318B). 318B). The plurality of tension applying members (406A to 406D) are arranged in a region of the periphery of the second mating surface (310) corresponding to at least one of the first and second connectors (318A, 318B). An electric machine (100) according to claim 3, wherein the electric machine (100) is provided with: formed on the side corresponding to at least one of the first and second connectors (318A, 318B) of the peripheral edge of the first mating surface (202) and the peripheral edge of the second mating surface (310). Claim 3, further comprising a plurality of bosses (206A-D, 314A-D), and the holes (204A-D, 312A-D) are formed in the bosses (206A-D, 314A-D). Electrical machine (100) as described. 6. The method of claim 1, wherein the holes (204A-D, 312A-D) are formed in the first mating surface (202) and the second mating surface (310) at a predetermined distance. Electrical machine (100) according to any one of the claims. at least one of the distances between the adjacent holes (204A-D, 312A-D) formed in the first mating surface (202) and the second mating surface (310) is less than 30 mm; Electric machine (100) according to any one of claims 1 to 6. Electric machine (100) according to any of the preceding claims, wherein the sealing element (402) is a rubber-coated metal gasket. An electric machine (100) according to any preceding claim, wherein the plurality of tensioning members (406A-D) are spring pins. Claim further comprising at least two pins (408) formed in the second housing (120) to align the first housing (110) with the second housing (120). The electric machine (100) according to any one of 1 to 9.

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