Electric compressor

Abstract

An embodiment of the present invention provides an electric compressor comprising: a housing; a compression part provided in the housing; a motor part provided in the housing and driving the compression part; and an inverter part for controlling the motor part, wherein: the inverter part includes a circuit board which is seated on a partition wall of the housing and on which one or more switching elements are mounted, and an insulating metal substrate disposed between the circuit board and the partition wall; and an insulating metal substrate includes one or more bent parts bent toward the circuit board to be coupled to the circuit board.

Description

electric compressor

[0001] The present invention relates to an electric compressor, and more particularly, to an electric compressor in which an insulating metal substrate (IMS) for heat dissipation of a switching element is soldered to a circuit board through a bending portion, thereby enabling easy assembly of the insulating metal substrate without a separate fixing member.

[0002] Automobiles are typically equipped with an air conditioning system to cool and heat the interior. This system includes a compressor that compresses low-temperature, low-pressure gaseous refrigerant drawn from the evaporator into high-temperature, high-pressure gaseous refrigerant and sends it to the condenser.

[0003] Compressors used in these automobiles include mechanical compressors that are driven by the driving force of the engine and electric compressors that use motors driven by electricity. Recently, as electrification in automobiles has accelerated, the use of electric compressors has been increasing.

[0004] Meanwhile, compressors can be divided into reciprocating compressors, which compress the refrigerant through the reciprocating motion of a piston, and rotary compressors, which compress the refrigerant through a rotary motion. Reciprocating compressors include crank compressors, which use a crank to transmit the refrigerant to multiple pistons, and swash plate compressors, which transmit the refrigerant through a rotating shaft equipped with a swash plate. Rotary compressors include vane rotary compressors, which use a rotating rotary shaft and vanes, and scroll compressors, which use an orbiting scroll and a fixed scroll.

[0005] Additionally, active development is underway in electric compressors featuring inverter-type compressors capable of variable motor speed. An example of a conventional inverter-type electric compressor is disclosed in Republic of Korea Patent Publication No. 2023-0017728.

[0006] According to an example of a conventional electric compressor, an electric compressor (10) includes a housing (11), a compression unit (16), an electric motor (17), and an inverter (30). The housing (11) has a motor housing member (12) that accommodates the compression unit (16) and the electric motor (17), and a discharge housing member (13). An inverter cover (25) is coupled to a single wall (12b) of the motor housing member (12), and the inverter cover (25) defines an inverter accommodation chamber (26) by being joined to the single wall (12b).

[0007] An inverter (30) has a circuit board (31) and one or more electrical components (32) mounted on the circuit board (31). The electrical components (32) are placed between the circuit board (31) and a single wall (12b) of a motor housing member (12), and are thermally coupled to the single wall (12b).

[0008] Conventionally, the electrical component (32) is spaced apart from the wall (12b) and the space between them is filled with a gap filler. In this case, there is a disadvantage in that the amount of gap filler applied is large, resulting in high cost.

[0009] The purpose of the present invention is to provide an electric compressor in which an insulating metal substrate (IMS) for heat dissipation of a switching element is soldered to a circuit board through a bending portion, thereby enabling easy assembly of the insulating metal substrate without a separate fixing member.

[0010] The technical problems to be solved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0011] In order to solve the above problem, one embodiment of the present invention provides an electric compressor including a housing; a compression unit provided within the housing; a motor unit provided within the housing and driving the compression unit; and an inverter unit controlling the motor unit; wherein the inverter unit includes a circuit board mounted on a partition wall of the housing and having one or more switching elements mounted thereon; and an insulating metal substrate disposed between the circuit board and the partition wall; wherein the insulating metal substrate includes one or more bending portions bent toward the circuit board and coupled to the circuit board.

[0012] According to an embodiment, the insulating metal substrate may be positioned at a position corresponding to the one or more switching elements.

[0013] According to an embodiment, the circuit board may be provided with one or more insertion holes into which the one or more bending portions are inserted.

[0014] According to an embodiment, the insertion hole may be formed in a slit shape that is relatively narrow in the width direction and relatively long in the length direction.

[0015] According to an embodiment, the insertion holes are formed in a plurality, and the longitudinal direction of some of the insertion holes among the plurality of insertion holes may be different from the longitudinal direction of the remaining insertion holes.

[0016] According to an embodiment, the bending portion may include an insert portion that is inserted into the insertion hole and soldered to the circuit board.

[0017] According to an embodiment, the bending portion may further include a stopper that is supported by contacting one surface of the circuit board around the insertion hole.

[0018] According to an embodiment, the circuit board is provided with a fastening hole through which a fastening member for fastening the circuit board to the housing passes, and the insertion hole may have a cross-sectional area smaller than the fastening hole.

[0019] According to an embodiment, the one or more bends may be soldered to the circuit board at a position spaced apart from the one or more switching elements by a minimum creepage distance.

[0020] According to an embodiment, a gap filler may be filled between the one or more switching elements and the insulating metal substrate.

[0021] According to an embodiment, the bulkhead may be provided with a heat exchanger at a position facing the insulating metal substrate.

[0022] According to an embodiment, the heat exchanger may be formed to protrude toward the circuit board.

[0023] According to an embodiment, the heat exchanger may be formed to protrude toward the motor unit.

[0024] According to an embodiment, a gap filler may be filled between the insulating metal substrate and the heat exchanger.

[0025] According to an embodiment, the switching element may include one or more first switching elements arranged along a first direction, and one or more second switching elements arranged along a second direction different from the first direction, and the bending portion may include a first bending portion arranged between the first switching elements and the second switching elements that are most closely adjacent to each other, a second bending portion arranged on an opposite side of the first bending portion with the one or more first switching elements interposed therebetween, and a third bending portion arranged on an opposite side of the first bending portion with the one or more second switching elements interposed therebetween.

[0026] According to an embodiment, the switching element includes a lead wire soldered to the circuit board so as to be electrically connected to the circuit board, and the insulating metal substrate can be arranged to cover all of the lead wires of the switching element.

[0027] According to an embodiment, the insulating metal substrate includes a main body portion and an extension portion extending from the main body portion, and the extension portion can cover the lead wire of the switching element.

[0028] According to the present invention, an insulating metal substrate (IMS) is disposed between the switching element and the housing, so that the insulating metal substrate disperses heat from the switching element toward the housing, thereby enabling heat dissipation of the switching element. Ultimately, the insulating metal substrate can improve the insulation and heat dissipation properties of the switching element.

[0029] In particular, since the insulating metal substrate is soldered to the circuit board through the bending portion, the insulating metal substrate can be easily assembled without a separate fixing member. In other words, the insulating metal substrate and the circuit board can be integrated.

[0030] Additionally, when the bending portion has a step, the insulating metal substrate can be assembled while maintaining a certain distance from the switching element.

[0031] Additionally, the insulating metal substrate shields all of the lead wires of the switching elements, thereby insulating them from the bulkhead of the motor housing.

[0032] The effects of the present invention are not limited to the effects described above, and should be understood to include all effects that can be inferred from the detailed description of the present invention or the composition of the invention described in the claims.

[0033] FIG. 1 is an exploded perspective view of an electric compressor according to one embodiment of the present invention, with the inverter unit separated.

[0034] Figure 2 is a perspective view of the circuit board and the insulating metal substrate in Figure 1 viewed from different directions.

[0035] Figure 3 is a partial cross-sectional view of Figure 2 when combined.

[0036] Figure 4 is a back view of the circuit board of Figure 1.

[0037] Figure 5 is a rear perspective view of the insulating metal substrate of Figure 1.

[0038] Figure 6 is a front view of the insulating metal substrate of Figure 1.

[0039] Figure 7 is an enlarged view of part A of Figure 5.

[0040] Fig. 8 is a cross-sectional view schematically illustrating the structure between the circuit board and the housing in the combined state of Fig. 1.

[0041] Hereinafter, a preferred embodiment of the electric compressor of the present invention will be described with reference to the attached drawings.

[0042] In addition, the terms described below are terms defined in consideration of the functions in the present invention, and may vary depending on the intention or custom of the user or operator. The examples below do not limit the scope of the present invention, but are merely exemplary matters of the components presented in the claims of the present invention.

[0043] To clearly explain the present invention, irrelevant parts have been omitted, and the same reference numerals are used throughout the specification to refer to identical or similar components. Throughout the specification, when a part is said to "include" a certain component, unless specifically stated otherwise, this does not mean that other components may be included, but rather that other components may be included.

[0044] Furthermore, components represented as "~bu" throughout the specification may be two or more components combined into a single component, or a single component may be further subdivided into two or more components with more detailed functions. Furthermore, each component described below may, in addition to its own primary function, additionally perform some or all of the functions performed by other components. Furthermore, some of the primary functions of each component may be exclusively performed by other components.

[0045]

[0046] First, let us briefly look at the configuration of an electric compressor (1) according to one embodiment of the present invention with reference to FIG. 1.

[0047] The electric compressor (1) of the present invention largely includes a housing (10), a motor section, a compression section, and an inverter section (20).

[0048] The housing (10) forms the exterior of the electric compressor (1), and in this embodiment, is composed of a front housing (motor housing, 12) and a rear housing (14).

[0049] The motor unit is provided within the front housing (12) and provides power for the compression unit to compress the refrigerant. Although not shown, the motor unit may include a rotor coupled to a rotating shaft rotatably installed at the center of the front housing (12) and a stator fixed to the front housing (12) and positioned radially outside the rotor. In addition, the stator may include a stator core and a coil wound around the stator core.

[0050] The compression unit is provided within the rear housing (14), and although not shown, may include a rotating scroll coupled to a rotating shaft via an eccentric bush, and a fixed scroll forming a compression chamber in which refrigerant is compressed together with the rotating scroll. In this way, since the compression unit is connected to the motor unit via the rotating shaft, the rotational force generated in the motor unit can be transmitted to the rotating scroll of the compression unit via the rotating shaft. However, the present invention is not limited thereto, and it is obvious that other types of compression units may be used.

[0051] The inverter unit (20) is arranged on one side of the housing (10), but is arranged on the opposite side of the compression unit with respect to the motor unit. The inverter unit (20) is electrically connected to the motor unit, and supplies power to the motor unit and controls its operation through power and control signals transmitted from the outside. Specifically, the stator forms an electromagnetic field by the power supplied from the inverter unit (20), and as the rotor rotates by the electromagnetic field formed by the stator, a rotational force for driving the compression unit is generated.

[0052] At this time, the motor unit and the inverter unit (20) can be electrically connected by a connecting pin. Since a 3-phase motor is used in this embodiment, three connecting pins may be provided, each connected to the 3 phases, in order to supply 3-phase power from the inverter unit (20) to the motor unit. The three connecting pins are electrically connected to the 3-phase coils of the stator, respectively, and are electrically connected to the circuit board (300) of the inverter unit (20) by penetrating the front housing (12). Specifically, each of the three connecting pins passes through the partition wall (12a) of the front housing (12) and then to the circuit board (300) to be electrically connected to the circuit board (300). To this end, a through hole for the connecting pin to pass through may be formed in each of the partition wall (12a) of the front housing (12) and the circuit board (300).

[0053]

[0054] Hereinafter, the inverter unit (20) will be examined in detail with reference to FIGS. 1 to 8. The inverter unit (20) may include an inverter cover (100), a first fastening member (200), a circuit board (300), a second fastening member (400), and an insulating metal substrate (500).

[0055] The inverter cover (100) is coupled to one side of the housing (10), specifically, the front housing (12), and serves to protect the inverter unit from external impact or dust by covering the circuit board (300). The inverter cover (100) is coupled to the front housing (12) by a first fastening member (200) to be described later, and for this purpose, a first fastening hole (110) is formed in the inverter cover (100) for the first fastening member (200) to pass through. Although not limited thereto, in the present embodiment, the inverter cover (100) is formed by a pressed metal plate.

[0056] The first fastening member (200) is for fastening the inverter cover (100) to the housing (10), and may be, for example, a fastening bolt. The first fastening member (200) is fastened to the front housing (12) by passing through the first fastening hole (110) of the inverter cover.

[0057] As illustrated in FIG. 1, a circuit board (PCB; 300) on which one or more switching elements (350) are mounted is mounted on a partition wall (12a) of a front housing (12). The partition wall (12a) of the front housing (12) separates a space where a motor unit is placed and a space where a circuit board (300) is placed, and serves to support the circuit board (300). Since the space where the circuit board (300) is placed is open, it is covered by an inverter cover (100). The circuit board (300) is joined to the front housing (12) by a second fastening member (400) to be described later, and for this purpose, a second fastening hole (310) is formed in the circuit board (300) for the second fastening member (400) to pass through.

[0058] The second fastening member (400) is for fastening the circuit board (300) to the housing (10), and may be, for example, a fastening bolt. The second fastening member (400) is fastened to the front housing (12) by penetrating the second fastening hole (310) of the circuit board.

[0059] In this embodiment, the switching element (350) is composed of a plurality of switching elements, and the plurality of switching elements (350) are mounted on one surface facing the front housing (12) of the circuit board (300). The switching element (350) may be a Mosfet, an IGBT, etc., and may be mounted on the surface of the circuit board (300) as an SMD type element. The switching element (350) includes a lead wire (352) that extends from the main body and is soldered to the circuit board (300) so as to be electrically connected to the circuit board (300). The heat generated from the switching element (350) can be cooled by a low-temperature, low-pressure refrigerant that is introduced into the space where the motor unit is placed. Specifically, the heat generated from the switching element (350) is transferred to the partition wall (12a) of the front housing (12) and cooled by the low-temperature, low-pressure refrigerant that comes into contact with the partition wall (12a).

[0060] At this time, in order to improve the insulation and heat dissipation characteristics of the switching element (350), in the present invention, an insulated metal substrate (IMS; Insulated Metal Substrate, 500) is disposed between the circuit board (300) and the partition wall (12a) of the front housing (12). The insulated metal substrate is generally composed of a metal base plate covered with a thin dielectric layer. The insulated metal substrate (500) is disposed between the switching element (350) and the partition wall (12a) of the front housing (12), so as to disperse the heat of the switching element (350) toward the front housing (12), thereby enabling heat dissipation of the switching element (350). To this end, the insulated metal substrate (500) is disposed at a position corresponding to a plurality of switching elements (350). That is, the shape of the insulated metal substrate (500) may vary depending on the arrangement of the switching elements (350), and the insulated metal substrate (500) is formed in a shape that can cover all of the plurality of switching elements (350).

[0061] In particular, the insulating metal substrate (500) is arranged to cover all of the lead wires (352) of the switching element (350). To this end, as illustrated in FIGS. 4 to 6, the insulating metal substrate (500) may include a main body (510) and an extension portion (530) extended from the main body (510) to cover the lead wires (352) of the switching element (350). In this way, the insulating metal substrate (500) shields all of the lead wires (352) of the switching element (350), thereby enabling insulation from the partition wall (12a) of the front housing.

[0062] As illustrated in Fig. 1, a heat exchange unit (12b) may be provided on the bulkhead (12a) of the front housing (12) at a position facing the insulating metal substrate (500). In the present embodiment, the heat exchange unit (12b) is formed to protrude toward the circuit board (300). However, this is not limited thereto, and the heat exchange unit (12b) may also be formed to protrude toward the motor unit, i.e., in the opposite direction to the circuit board (300). Accordingly, the heat of the switching element (350) is transferred to the heat exchange unit (12b), and the heat transferred to the heat exchange unit (12b) can be effectively cooled by the low-temperature, low-pressure refrigerant contained inside the heat exchange unit (12b).

[0063] At this time, the insulating metal substrate (500) is floating between the switching element (350) and the heat exchanger (12b). Therefore, when assembling the inverter unit, the insulating metal substrate (500) must first be fixed to the front housing (12) using a separate fixing member, and then the circuit board (300) must be assembled. In this case, the assembly process is complicated. Therefore, to solve this problem, the insulating metal substrate (500) of the present invention includes one or more bending portions (520) that are bent from the main body (510) toward the circuit board (300) and coupled to the circuit board (300). Accordingly, after the insulating metal substrate (500) and the circuit board (300) are integrated, the integrated insulating metal substrate (500) and the circuit board (300) can be assembled together to the front housing (12) using the second fastening member (400). Therefore, the insulating metal substrate (500) can be easily assembled without a separate fixing member.

[0064] Since a gap is formed between the switching element (350) and the insulating metal substrate (500), as illustrated in FIG. 8, a first gap filler (620) can be filled between the switching element (350) and the insulating metal substrate (500). The first gap filler (620) has insulating properties and fills the gap between the switching element (350) and the insulating metal substrate (500), thereby effectively controlling heat by minimizing heat transfer interference from air or foreign substances, and transferring heat from the switching element (350) to the insulating metal substrate (500).

[0065] In addition, since a gap is formed between the insulating metal substrate (500) and the heat exchange unit (12b), as illustrated in Fig. 8, a second gap filler (640) can be filled between the insulating metal substrate (500) and the heat exchange unit (12b). The second gap filler (640) has the same characteristics as the first gap filler (620) and serves to transfer heat from the insulating metal substrate (500) to the heat exchange unit (12b).

[0066] In this way, heat is effectively transferred from the switching element (350) to the heat exchanger (12b) through the first and second gap fillers (620, 640), so that heat dissipation of the switching element (350) can be effectively achieved. In the case of a general gap filler, a curing time is required in the form of a liquid, but in the case of having the structure of the insulating metal substrate (500) as described above, room temperature and general curing are possible.

[0067] Specifically, the circuit board (300) is provided with one or more insertion holes (320) into which one or more bending parts (520) are inserted, and the bending parts (520) are soldered after passing through the insertion holes (320) of the circuit board. At this time, in order to secure a space for arranging the switching elements, it is preferable that the insertion holes (320) be formed to have a smaller cross-sectional area than the fastening holes (310). In the present embodiment, the insertion holes (320) are formed in a slit shape that is relatively narrow in the width direction and relatively long in the length direction.

[0068] In this embodiment, both the bending portion (520) and the insertion hole (320) are formed in multiple numbers. At this time, it is preferable that the longitudinal direction of some of the insertion holes (320) be formed differently from the longitudinal direction of the remaining insertion holes.

[0069] Specifically, the bending portion (520) includes an insertion portion (522) that is inserted into the insertion hole (320) and soldered to the circuit board (300), and a stopper (524) that is supported by contacting one surface of the circuit board (300) around the insertion hole (320). The stopper (524) is bent and extended from the main body (510), and the insertion portion (522) is further extended from the stopper (524). The insertion portion (522) has a size that can be inserted into the insertion hole (320), and the stopper (524) has a size that cannot be inserted into the insertion hole (320). Accordingly, a step is formed between the insertion portion (522) and the stopper (524), and the stopper (524) serves to stop the circuit board (300) by contacting one surface of the circuit board (300) without passing through the insertion hole (320). Therefore, the insulating metal substrate (500) can be assembled while maintaining a certain distance from the switching element (350).

[0070] At this time, the bending portion (520) is soldered to the circuit board (300) at a position spaced apart from the switching element (350) by a minimum creepage distance. The creepage distance is defined as the shortest distance along the surface of the insulating material between two conductive objects. Therefore, the shortest distance from the switching element (350) along the surface of the insulating metal substrate (500) to the circuit board (300) corresponds to the creepage distance, and the position at which the bending portion (520) is soldered is set so that this creepage distance satisfies a minimum value or more. Referring to FIG. 4, it can be seen that in order to satisfy the minimum creepage distance, a plurality of insertion holes (320) into which a plurality of bending portions (520) are inserted are provided at a certain distance from the switching element (350) that is located closest to them, respectively.

[0071] Specifically, in the present embodiment, the plurality of switching elements (350) include one or more first switching elements (350a) arranged along a first direction, and one or more second switching elements (350b) arranged along a second direction different from the first direction. That is, one or more first switching elements (350a) are arranged in a row in the first direction, and one or more second switching elements (350b) are arranged in a row in the second direction. In one embodiment, the first switching elements (350a) and the second switching elements (350b) may be arranged perpendicular to each other.

[0072] In this case, the plurality of bending portions (520) may include a first bending portion (520a) positioned between the closest adjacent first switching elements (350a) and second switching elements (350b), a second bending portion (520b) positioned on the opposite side of the first bending portion (520a) with one or more first switching elements (350a) therebetween, and a third bending portion (520c) positioned on the opposite side of the first bending portion (520a) with one or more second switching elements (350b) therebetween.

[0073] In response to this, a plurality of insertion holes (320) may also be included, including a first insertion hole (320a) into which a first bending portion (520a) is inserted, a second insertion hole (320b) into which a second bending portion (520b) is inserted, and a third insertion hole (320c) into which a third bending portion (520c) is inserted.

[0074] Accordingly, the insulating metal substrate (500) can be firmly fixed to the circuit board (300) while satisfying the minimum creepage distance.

[0075] The present invention is not limited to the specific embodiments and descriptions described above, and anyone with ordinary skill in the art to which the present invention pertains can make various modifications without departing from the gist of the present invention as claimed in the claims, and such modifications are within the protection scope of the present invention.

[0076] The present invention relates to an electric compressor in which an insulating metal substrate (IMS) for heat dissipation of a switching element is soldered to a circuit board through a bending portion, thereby enabling easy assembly of the insulating metal substrate without a separate fixing member.

Claims

1. Housing; A compression unit provided within the housing; A motor unit provided within the housing and driving the compression unit; and It includes an inverter section that controls the above motor section; The above inverter part, A circuit board mounted on the bulkhead of the housing and having one or more switching elements mounted thereon; and Including an insulating metal substrate disposed between the circuit board and the bulkhead; An electric compressor, characterized in that the insulating metal substrate includes one or more bending portions that are bent toward the circuit board and bonded to the circuit board.

2. In paragraph 1, An electric compressor, characterized in that the insulating metal substrate is arranged at a position corresponding to the one or more switching elements.

3. In paragraph 1, An electric compressor, characterized in that the circuit board is provided with one or more insertion holes into which the one or more bending parts are inserted.

4. In paragraph 3, An electric compressor, characterized in that the above insertion hole is formed in a slit shape that is relatively narrow in the width direction and relatively long in the length direction.

5. In paragraph 4, An electric compressor characterized in that the insertion holes are formed in a plurality, and the longitudinal direction of some of the insertion holes among the plurality of insertion holes is different from the longitudinal direction of the remaining insertion holes.

6. In paragraph 3, An electric compressor, characterized in that the above-mentioned bending portion includes an insertion portion that is inserted into the insertion hole and soldered to the circuit board.

7. In paragraph 6, An electric compressor, characterized in that the above-mentioned bending portion further includes a stopper that is supported by contacting one surface of the circuit board around the insertion hole.

8. In paragraph 3, The circuit board is provided with a fastening hole through which a fastening member for fastening the circuit board to the housing passes. An electric compressor, characterized in that the insertion hole has a smaller cross-sectional area than the fastening hole.

9. In paragraph 1, An electric compressor, characterized in that the at least one bending portion is soldered to the circuit board at a position spaced apart from the at least one switching element by a minimum creepage distance.

10. In paragraph 1, An electric compressor, characterized in that a gap filler is filled between the one or more switching elements and the insulating metal substrate.

11. In paragraph 1, An electric compressor, characterized in that a heat exchanger is provided in the above bulkhead at a position facing the above insulating metal substrate.

12. In paragraph 11, An electric compressor, characterized in that the heat exchanger is formed to protrude toward the circuit board.

13. In paragraph 11, An electric compressor, characterized in that the heat exchanger is formed to protrude toward the motor unit.

14. In paragraph 11, An electric compressor, characterized in that a gap filler is filled between the insulating metal substrate and the heat exchange unit.

15. In paragraph 2, The switching element includes one or more first switching elements arranged along a first direction and one or more second switching elements arranged along a second direction different from the first direction, An electric compressor, characterized in that the bending portion includes a first bending portion arranged between the first switching element and the second switching element that are most closely adjacent to each other, a second bending portion arranged on the opposite side of the first bending portion with the one or more first switching elements interposed therebetween, and a third bending portion arranged on the opposite side of the first bending portion with the one or more second switching elements interposed therebetween.

16. In paragraph 2, The above switching element includes a lead wire soldered to the circuit board so as to be electrically connected to the circuit board, An electric compressor, characterized in that the insulating metal substrate is arranged to cover all of the lead wires of the switching element.

17. In paragraph 16, An electric compressor, characterized in that the insulating metal substrate includes a main body and an extension portion extending from the main body portion, and the extension portion covers the lead wire of the switching element.

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