Inverter-integrated electric compressor and method for manufacturing same

Abstract

The invention provides an inverter-integrated electric compressor which can reduce the weight and production cost of a cover for closing an inverter housing part and can suppress vibration and noise caused by resonance. An electric compressor is provided with a cover (15) that closes an inverter housing section (13). The cover (15) is made of a metal plate. The metal plate is provided with a shell-shaped upper wall part (41), a vertical wall part (42) which is continuously formed with the outer periphery of the upper wall part, and a sealing flange part (46) which continuously extends outwards from the outer periphery of the vertical wall part and is installed on the housing (11). The natural frequency of the cover is shifted from the point of resonance with the starting force of the compression mechanism (4) and the electric motor (2) by adjusting the radius of curvature of an arch part constituting the shell shape of the upper wall part and the angle at which the vertical wall part rises from the sealing flange part.

Description

Technical Field

[0001] The present invention relates to an inverter-integrated electric compressor including a cover for closing an inverter housing portion formed in a casing, and a method for manufacturing the same. Background Art

[0002] Conventionally, in such an inverter-integrated electric compressor, especially an electric compressor constituting a vehicle air conditioning device, the inverter is housed and fixed in an inverter housing (inverter housing) formed in a metal housing, and the inverter housing is sealed with a cover. Here, the cover is usually made of a thin plate of an aluminum die casting because it does not need to be designed to withstand pressure. However, if the vibration of the compression mechanism or motor in the housing is transmitted to the cover, it will vibrate and generate noise.

[0003] In this case, if the frequency of the excitation force of the compression mechanism or the motor is consistent with or close to the natural vibration frequency of the cover, resonance occurs, and there is a problem of increased vibration and noise. Therefore, an electric compressor has been proposed that has a method of forming a groove in the cover to deviate the natural vibration frequency of the cover from the resonance (for example, see Patent Document 1). Prior art literature Patent Literature

[0004] Patent Document 1: Japanese Patent No. 5510490 Summary of the invention Problems to be Solved by the Invention

[0005] However, when aluminum die casting is used to manufacture a shape like that of Patent Document 1, it is difficult to achieve lightweighting, and the height dimension becomes larger when thickening, so it is difficult to design compactly. Furthermore, in the case of aluminum die casting, after casting (die casting) from an aluminum alloy ingot, multiple processes such as heat treatment to eliminate strain and cutting are required, which increases the amount of carbon dioxide emissions and makes it difficult to cope with carbon neutrality. In addition, the structure of Patent Document 1 has the problem that the natural vibration frequency can only be deviated in a low direction.

[0006] The present invention has been made to solve such conventional problems, and its object is to provide an inverter-integrated electric compressor and a method for manufacturing the same that can reduce the weight and production cost of a cover that seals an inverter housing and can also suppress vibration and noise caused by resonance. Means for solving problems

[0007] The inverter-integrated electric compressor of the present invention is characterized in that it comprises: a metal casing with a motor and a compression mechanism built in; an inverter for driving the motor; an inverter storage portion, which is composed of the casing and stores the inverter; and a metal cover, which closes the inverter storage portion, and the cover is composed of a metal plate, which has: a shell-shaped upper wall portion; a longitudinal wall portion, which is continuously formed with the outer periphery of the upper wall portion; and a sealing flange portion, which continuously extends outward from the outer periphery of the longitudinal wall portion and is installed on the casing, and the natural vibration frequency of the cover is deviated from the resonance point with the compression mechanism and the excitation force of the motor by adjusting the curvature radius of the shell-shaped arch portion constituting the upper wall portion and / or the angle at which the longitudinal wall portion stands up from the sealing flange portion.

[0008] The inverter-integrated electric compressor according to claim 2 of the invention is characterized in that, in the above invention, the radius of curvature of the arched portion of the cover has different values ​​in the long-side direction and the short-side direction.

[0009] The inverter-integrated electric compressor according to claim 3 of the invention is characterized in that, in the above invention, the radius of curvature in the long-side direction of the arched portion of the cover is larger than the radius of curvature in the short-side direction.

[0010] The inverter-integrated electric compressor according to claim 4 is characterized in that, in the invention according to claim 1 , the shell shape of the cover is composed of a plurality of arched portions having different curvature radii.

[0011] The inverter-integrated electric compressor according to claim 5 is characterized in that, in each of the above inventions, the vertical wall portion stands at an angle of 30° or more and 75° or less from the sealing flange portion.

[0012] The inverter-integrated electric compressor according to claim 6 is characterized in that, in the inventions according to claims 1 to 4, the height dimension of the cover is 8 mm or more and 20 mm or less.

[0013] The manufacturing method of the inverter-integrated electric compressor of Technical Solution 7 is characterized in that when manufacturing an inverter-integrated electric compressor having a metal casing with a built-in motor and a compression mechanism, an inverter for driving the motor, an inverter storage portion formed by the casing and storing the inverter, and a metal cover that closes the inverter storage portion, the cover is formed by a metal plate, the metal plate having a shell-shaped upper wall portion, a longitudinal wall portion formed continuously with the outer periphery of the upper wall portion, and a sealing flange portion extending continuously outward from the outer periphery of the longitudinal wall portion and installed on the casing, the curvature radius of the shell-shaped arch portion constituting the upper wall portion and / or the angle at which the longitudinal wall portion stands up from the sealing flange portion are adjusted so that the natural vibration frequency of the cover deviates from the resonance point with the excitation force of the compression mechanism and the motor. Effects of the Invention

[0014] According to the invention of Technical Solution 1 and Technical Solution 7, in an inverter-integrated electric compressor having a metal casing with a built-in motor and a compression mechanism, an inverter for driving the motor, an inverter housing portion formed by the casing and housing the inverter, and a metal cover for closing the inverter housing portion, the cover is composed of a metal plate, and the metal plate has a shell-shaped upper wall portion, a longitudinal wall portion formed continuously with the outer periphery of the upper wall portion, and a sealing flange portion extending outward continuously with the outer periphery of the longitudinal wall portion and mounted on the casing. By adjusting the curvature radius of the shell-shaped arch portion constituting the upper wall portion and / or the angle at which the longitudinal wall portion stands from the sealing flange portion, the natural vibration frequency of the cover is deviated from the resonance point with the excitation force of the compression mechanism and the motor, thereby being able to suppress the undesirable condition of cover resonance caused by vibration of the compression mechanism and the motor.

[0015] Thus, the vibration and noise caused by resonance can be greatly reduced. In particular, the cover is made of metal plate, so compared with aluminum die castings, it can be manufactured by stamping steel plates, the number of processes is reduced and energy is saved, so the carbon dioxide emissions can be greatly reduced, which can help environmental issues and reduce production costs. In addition, for aluminum die castings, the natural vibration frequency is deviated by changing the wall thickness, but in the present invention, a metal plate with a substantially constant plate thickness can be formed, and the natural vibration frequency can be deviated, so that lightweight can be achieved. In the case of an air conditioning device for a vehicle, the performance of the vehicle can also be improved. Furthermore, the upper wall portion of the cover made of metal plate is set to a shell shape, and a longitudinal wall portion is formed on its periphery, and then a sealing flange portion is formed, which has the effect of also improving the strength of the cover itself.

[0016] In this case, as in the invention of claim 2, by setting the radius of curvature of the arched portion of the cover to different values ​​in the long-side direction and the short-side direction, the adjustment range of the natural frequency of the cover can be expanded.

[0017] In particular, as in the invention of claim 3, by making the radius of curvature of the arched portion of the cover in the long side direction larger than the radius of curvature in the short side direction, the increase in the height dimension of the cover can be suppressed, and the increase in the overall size of the electric compressor can also be suppressed.

[0018] In addition, even when the shell shape of the cover is composed of a plurality of arched portions having different curvature radii as in the invention of claim 4, it is possible to suppress an increase in the height dimension of the cover and also suppress an increase in the size of the entire electric compressor.

[0019] Furthermore, as in the invention of claim 5, by adjusting the rising angle of the vertical wall portion from the sealing flange portion within a range of 30° to 75°, the natural frequency of the cover can be effectively shifted from the resonance point.

[0020] In addition, as in the invention of claim 6, by setting the height dimension of the cover to a range of 8 mm to 20 mm, the second moment of area of ​​the cover is adjusted, and the natural frequency can be effectively shifted from the resonance point. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic cross-sectional view of an inverter-integrated electric compressor according to an embodiment of the present invention (Example 1). Figure 2 Is closed Figure 1 A top view of a cover of an inverter housing portion of an electric compressor. Figure 3 yes Figure 2 A side view of the long side direction of the cover. Figure 4 yes Figure 2 A side view of the short side of the hood. Figure 5 yes Figure 2 Rear view of the hood. Figure 6 yes Figure 2 CC line section view. Figure 7 yes Figure 5 BB line cross-sectional view. Figure 8 This is a plan view of a cover according to another embodiment of the present invention for sealing an inverter housing portion of an electric compressor (Example 2). Fig. 9 yes Figure 8 A side view of the long side direction of the cover. Fig.10 yes Figure 8 A side view of the short side of the hood. Fig.11 yes Figure 8 Rear view of the hood. Fig.12 yes Figure 8 DD line cross-sectional view of the hood. Fig.13 yes Figure 8 EE line cross-sectional view of the hood. Fig.14 yes Figure 8 FF line cross-sectional view of the hood. DETAILED DESCRIPTION

[0022] Hereinafter, embodiments of the present invention will be described in detail based on the drawings. Example 1

[0023] Figure 11 is a schematic cross-sectional view of an inverter-integrated electric compressor 1 to which an embodiment of the present invention is applied. The electric compressor (inverter-integrated electric compressor) 1 of the embodiment is a so-called horizontal inverter-integrated scroll electric compressor, which is used, for example, in a refrigerant circuit constituting an air conditioning device for an electric vehicle, sucks in a refrigerant as a working fluid of the air conditioning device, compresses it, and then discharges it to a discharge pipe. The inverter-integrated electric compressor 1 includes a three-phase electric motor 2 as a motor of the present invention, an inverter 3 for operating the electric motor 2, and a scroll compression mechanism 4 as a compression mechanism driven by the electric motor 2.

[0024] In the embodiment, the electric compressor 1 comprises: a cylindrical stator housing 7, on the inside of which an electric motor 2 and a center plate 6 are housed; an inverter housing 8, which is mounted on an end wall 7A on one end side of the stator housing 7 and on the inside of which an inverter 3 is housed; and a rear housing 9, which is mounted on an open end surface on the other end side of the stator housing 7.

[0025] The stator housing 7 , the inverter housing 8 , and the rear housing 9 are all made of metal (in the embodiment, they are made of aluminum, except for a cover 15 described later), and are integrally joined to form a housing 11 of the electric compressor 1 of the embodiment.

[0026] The stator housing 7 includes a motor chamber 12 for housing the electric motor 2, and one end face of the motor chamber 12 is substantially closed by the end wall 7A of the stator housing 7. The other end face of the motor chamber 12 of the stator housing 7 is open, and after the electric motor 2 is housed in the motor chamber 12 through the opening, the center plate 6 is housed through the same opening. In addition, a sub-bearing 16 is attached to the inner surface (motor chamber 12 side) of the end wall 7A, and the sub-bearing 16 is used to rotatably support one end of the drive shaft 14 of the electric motor 2.

[0027] The center plate 6 is opened on the side opposite to the electric motor 2 (the other end side), and after accommodating the movable scroll member 22 of the scroll compression mechanism 4, the rear housing 9 to which the fixed scroll member 21 of the scroll compression mechanism 4 is fixed is fixed to the opening of the stator housing 7, thereby closing the opening.

[0028] In addition, a through hole 17 is opened in the center plate 6 for inserting the other end of the driving shaft 14 of the electric motor 2, and a main bearing 18 is installed in the center plate 6 on the side of the scroll compression mechanism 4 of the through hole 17. The main bearing 18 supports the other end of the driving shaft 14 on the side of the scroll compression mechanism 4 so that it can rotate.

[0029] The electric motor 2 is composed of a stator 25 on which a coil is wound and fixed to the inner side of the peripheral wall of the stator housing 7, and a rotor 23 that rotates inside the stator 25. For example, a direct current from a battery (not shown) of a vehicle is converted into a three-phase alternating current by an inverter 3, and power is supplied to the coil of the stator 25 of the electric motor 2, so that the rotor 23 is rotationally driven. The drive shaft 14 is fixed to the rotor 23.

[0030] In addition, the stator housing 7 is formed with a suction port 30, and the refrigerant sucked from the suction port 30 flows into the center plate 6 after passing through the motor chamber 12 of the stator housing 7, and is sucked by the suction portion 37 on the outside of the scroll compression mechanism 4. Thus, the electric motor 2 is cooled by the sucked refrigerant. In addition, the following structure is formed: the refrigerant compressed by the scroll compression mechanism 4 is discharged from the discharge chamber 27 described later through the discharge port 20 formed in the rear housing 9 to the discharge piping of the refrigerant circuit not shown outside the housing 11.

[0031] The scroll compression mechanism 4 is composed of the fixed scroll 21 and the movable scroll 22. The fixed scroll 21 is integrally provided with a disc-shaped mirror plate 23 and a spiral wrap 24 formed of an involute shape or a curve similar thereto and erected on the surface (one surface) of the mirror plate 23, and is fixed to the rear housing 9 with the surface of the mirror plate 23 on which the wrap 24 is erected as the center plate 6 side. A discharge hole 26 is formed in the center of the mirror plate 23 of the fixed scroll 21, and the discharge hole 26 is connected to the discharge chamber 27 in the rear housing 9. In the figure, "28" is an opening discharge valve provided on the back side (the other surface) side of the mirror plate 23 of the discharge hole 26.

[0032] The movable scroll 22 is a scroll that performs an orbital rotation motion relative to the fixed scroll 21, and is integrally provided with a disk-shaped mirror plate 31, a spiral wrap 32 formed of an involute shape or a curve similar thereto and erected on the surface (one surface) of the mirror plate 31, and a boss 33 protrudingly formed at the center of the back surface (the other surface) of the mirror plate 31. The movable scroll 22 is arranged such that the wrap 32 is protruded in the direction of the fixed scroll 21, the wrap 32 and the wrap 24 of the fixed scroll 21 are opposed to each other, face each other and mesh, and a pressure chamber 34 is formed between each wrap 24, 32.

[0033] That is, the wrap 32 of the movable scroll 22 is opposed to the wrap 24 of the fixed scroll 21, and meshes with each other in such a manner that the front end of the wrap 32 contacts the surface of the mirror plate 23, and the front end of the wrap 24 contacts the surface of the mirror plate 31, and an eccentric portion 36 eccentrically provided from the axis at the other end of the drive shaft 14 is engaged with the boss 33 of the movable scroll 22. Furthermore, if the drive shaft 14 rotates together with the rotor 23 of the electric motor 2, the movable scroll 22 does not rotate on its own, but performs an orbital rotation motion relative to the fixed scroll 21.

[0034] The movable scroll 22 revolves eccentrically relative to the fixed scroll 21, so the eccentric direction and contact position of each wrap 24, 32 move while rotating, and the pressure chamber 34 that sucks the refrigerant from the suction portion 37 on the outside moves inward while gradually shrinking. As a result, the refrigerant is compressed and finally discharged from the discharge hole 26 in the center to the discharge chamber 27 via the discharge valve 28.

[0035] exist Figure 1 38 is a circular thrust plate. The thrust plate 38 is used to divide the back pressure chamber 39 formed between the back side of the mirror plate 31 of the movable scroll 22 and the center plate 6 and the suction portion 37 on the outside of the scroll compression mechanism 4, and is located on the outside of the boss 33 and sandwiched between the center plate 6 and the movable scroll 22.

[0036] In addition, reference numeral 48 denotes a centrifugal oil separator installed in the discharge chamber 27 of the rear housing 9 (housing 11). The oil separator 48 separates the lubricating oil mixed in the refrigerant discharged from the scroll compression mechanism 4 to the discharge chamber 27, and the refrigerant is discharged to the discharge pipe toward the discharge port 20.

[0037] An oil storage chamber 44 is formed in the rear housing 9 below the oil separator 48, and the oil separated from the refrigerant by the oil separator 48 flows into the oil storage chamber 44 from the lower end of the oil separator 48. In the figure, 43 is a back pressure passage formed from the rear housing 9 to the center plate 6, and has a throttle hole 50. The discharge pressure adjusted by the pressure reduction in the throttle hole 50 of the back pressure passage 43 is configured to be supplied to the back pressure chamber 39 together with the oil in the oil storage chamber 44 separated by the oil separator 48.

[0038] The pressure (back pressure) in the back pressure chamber 39 generates a back pressure load that presses the movable scroll 22 toward the fixed scroll 21. The back pressure load overcomes the compression reaction force from the pressure chamber 34 of the scroll compression mechanism 4 and presses the movable scroll 22 toward the fixed scroll 21, maintaining the contact between the wraps 24 and 32 and the mirror plates 31 and 23, and compressing the refrigerant in the pressure chamber 34.

[0039] On the other hand, the inverter case 8 includes: a case body 10, which forms an inverter storage section 13 inside; and a cover 15 of the present invention, which closes an opening of one end surface of the case body 10. The inverter 3 is stored in the inverter storage section 13, and after the inverter 3 is stored in the inverter storage section 13, the cover 15 is attached to the case body 10.

[0040] exist Figure 1In the figure, reference numeral 40 denotes a sealing pin which passes through the partition wall 7A, has one end connected to the coil of the stator 25 of the electric motor 2 housed in the motor chamber 12 , and has the other end electrically connected to the inverter 3 housed in the inverter housing 13 .

[0041] Next, refer to Figure 2 to Figure 7 The shape of the cover 15 of this embodiment will be described. Figure 1 The cross section of the cover 15 is Figure 2 The cover 15 used in the present invention is formed by stamping (without cutting) a metal plate of a predetermined thin thickness dimension composed of a surface-treated steel plate. The cover 15 includes: Figure 1 The upper wall portion 41 is a shell-shaped upper wall portion 41 as shown in the figures; the vertical wall portion 42 is continuously formed with the outer periphery of the upper wall portion 41; and the sealing flange portion 46 continuously extends outward from the outer periphery of the vertical wall portion 42.

[0042] In addition, reference numeral 47 denotes a threaded hole formed in the sealing flange portion 46. Figure 1 The cover 15 is attached to the case body 10 by pressing the open end surface of the case body 10 as shown, inserting screws (not shown) into the threaded holes 47 and screwing them into the case body 10 .

[0043] Furthermore, the curvature radius R1 ( Figure 1 ) and the radius of curvature R2 in the short side direction ( Figure 6 ) are different, and the relationship of R1>R2 is achieved (the curvature radius R1 of the arched portion in the long side direction is greater than the curvature radius R2 in the short side direction). That is, for example, the curvature radius R1 in the long side direction is set to 430 mm, and the curvature radius R2 in the short side direction is set to 405 mm. In addition, the height dimension of the cover 15 is set to a range of 8 mm or more and 20 mm or less, and is set to 17 mm in the embodiment.

[0044] In addition, the angle X1 at which the vertical wall portion 42 rises from the sealing flange portion 46 is set to a range of 30° to 75°, and is set to 45° in the embodiment. In addition, the rising angle X1 is defined in the present invention as follows: Figure 7 As shown, the angle formed by the line L1 extending inward from the sealing flange portion 46 and the vertical wall portion 42 is shown.

[0045] Here, if the curvature radii R1 and R2 of the arched portion of the shell-shaped upper wall portion 41 are increased, the natural vibration frequency of the cover 15 becomes lower, and if the curvature radii R1 and R2 are reduced, the natural vibration frequency becomes higher. In addition, if the rising angle X1 of the vertical wall portion 42 is reduced, the connection with the upper wall portion 41 becomes smooth, so the natural vibration frequency of the cover 15 becomes higher, and if the rising angle X1 is increased, the natural vibration frequency becomes lower.

[0046] Therefore, in the embodiment, by adjusting the curvature radius R1 of the arched portion in the long-side direction and the curvature radius R2 of the arched portion in the short-side direction of the upper wall portion 41 of the cover 15, and the rising angle X1 of the vertical wall portion 42, the natural vibration frequency (mainly the primary natural vibration frequency) of the cover 15 is designed to deviate from the frequency of the excitation force of the compression mechanism 4 and the electric motor 2, which are the vibration sources of the electric compressor 1. In other words, the natural vibration frequency of the cover 15 is deviated from the resonance point with the excitation force of the compression mechanism 4 and the electric motor 2.

[0047] In addition, the frequency of the excitation force of the compression mechanism 4 and the electric motor 2 changes according to the operating state, so in this embodiment, the natural vibration frequency of the cover 15 is set to a range higher than the frequency of the excitation force (the frequency range of the excitation force generated in the operating state from low speed to high speed). For example, if the frequency range of the excitation force of the compression mechanism 4 and the electric motor 2 is 1100 Hz to 2000 Hz, the curvature radii R1 and R2 and the rising angle X1 are adjusted so that the natural vibration frequency of the cover 15 becomes 2100 Hz.

[0048] Thus, the undesirable situation that the cover 15 resonates due to the vibration of the compression mechanism 4 and the electric motor 2 can be suppressed, and the vibration and noise caused by the resonance of the cover 15 can be greatly reduced. In particular, the cover 15 is made of metal plate, so compared with aluminum die castings, it can be manufactured by stamping processing of surface-treated steel plates, the number of processes is reduced and energy is saved, so it is also possible to achieve a significant reduction in production costs and carbon dioxide emissions. In addition, for aluminum die castings, the natural vibration frequency is deviated by changing the wall thickness, but in the present invention, the natural vibration frequency of the cover 15 can be deviated by molding a metal plate with a substantially constant plate thickness, and a significant weight reduction can also be achieved. Furthermore, by making the upper wall portion 41 of the cover 15 made of metal plate into a shell shape, forming a longitudinal wall portion 42 on its outer periphery, and then forming a sealing flange portion 46, the strength of the cover 15 itself is also improved, and deformation caused by collision is also suppressed.

[0049] In addition, as in the embodiment, if the radius of curvature of the arched portion of the cover 15 is set to different values ​​in the long-side direction (R1) and the short-side direction (R2), it is possible to expand the adjustment range of the natural vibration frequency of the cover 15. In particular, as in this embodiment, by making the radius of curvature R1 in the long-side direction of the arched portion of the cover 15 larger than the radius of curvature R2 in the short-side direction, it is possible to suppress the increase in the height dimension of the cover 15, and also suppress the increase in the overall dimension of the electric compressor 1.

[0050] Furthermore, by adjusting the angle X1 at which the vertical wall portion 42 rises from the sealing flange portion 46 within a range of 30° to 75°, the natural vibration frequency of the cover 15 can be smoothly deviated from the resonance point. In addition, as in the embodiment, by setting the height dimension of the cover 15 within a range of 8 mm to 20 mm, the second moment of area of ​​the cover 15 can be obtained, and the natural vibration frequency can be effectively deviated from the resonance point. Example 2

[0051] Next, refer to Figure 8 to Figure 14 Another embodiment of the present invention is described. Figure 1 to Figure 7 The parts indicated by the same reference numerals have the same or similar functions. Figure 8 One side of line L2 ( Figure 8 The curvature radius R1 of the arched portion in the long side direction ( Fig.12 ) and the radius of curvature R2 in the short side direction ( Fig.13 ) is the same, on the other side of line L2 ( Figure 8 On the upper side of the arch portion), the curvature radius R1 of the arch portion in the long side direction is different from the curvature radius R2 in the short side direction, and the relationship is R1>R2 (the curvature radius R1 of the arch portion in the long side direction is greater than the curvature radius R2 in the short side direction).

[0052] in addition, Figure 8 The line L2 is located on or near the axis of the drive shaft 14 when the cover 15 is mounted on the housing body 10. That is, in the case of this embodiment, on the lower side of the line L2, for example, the curvature radius R1 in the long side direction and the curvature radius R2 in the short side direction are both set to 510 mm, and on the upper side of the line L2, for example, the curvature radius R1 in the long side direction is set to 1900 mm, and the curvature radius R2 in the short side direction is set to 510 mm. In addition, it is effective that the curvature radii R1 and R2 are greater than 300 mm and less than 2000 mm.

[0053] Thus, in the long side direction of the cover 15 of this embodiment, the curvature radius R1 of the arched portion is different on the lower side and the upper side of the line L2. This is a composite shape of a rotational curved surface and a circular parabola. In addition, the height dimension of the cover 15 is set to a range of 8 mm or more and 20 mm or less, and is set to 11 mm in the embodiment.

[0054] Furthermore, in this embodiment, the angle X1 at which the vertical wall portion 42 rises from the sealing flange portion 46 is set to a range of 30° to 75°, and is set to 60° in this embodiment. In addition, this rising angle X1 is also defined as follows in this embodiment: Fig.14 As shown, the angle formed by the line L1 extending inward from the sealing flange portion 46 and the vertical wall portion 42 is shown.

[0055] Furthermore, in this embodiment, the curvature radius R1 of the arched portion in the long-side direction and the curvature radius R2 of the arched portion in the short-side direction of the upper wall portion 41 of the cover 15, as well as the rising angle X1 of the vertical wall portion 42 are adjusted, and the natural vibration frequency (mainly the primary natural vibration frequency) of the cover 15 is designed to deviate from the frequency of the excitation force of the compression mechanism 4 and the electric motor 2, which are the vibration sources of the electric compressor 1. In other words, the natural vibration frequency of the cover 15 is deviated from the resonance point with the excitation force of the compression mechanism 4 and the electric motor 2.

[0056] That is, in this embodiment, the natural vibration frequency of the cover 15 is also set to a range higher than the frequency of the excitation force of the compression mechanism 4 and the electric motor 2. For example, if the frequency range of the excitation force of the compression mechanism 4 and the electric motor 2 is set to the above-mentioned 1100 Hz to 2000 Hz, the curvature radii R1 and R2 and the rising angle X1 are adjusted so that the natural vibration frequency of the cover 15 becomes 2200 Hz, thereby suppressing the undesirable situation that the cover 15 resonates due to the vibration of the compression mechanism 4 and the electric motor 2, and greatly reducing the vibration and noise caused by the resonance of the cover 15.

[0057] In particular, as in this embodiment, by setting the curvature radius R1 of the arched portion in the long-side direction of the shell-shaped cover 15 to two different curvature radii R1 (510 mm and 1900 mm in the embodiment) bounded by the line L2, it is possible to suppress the increase in the height dimension of the cover 15 and the increase in the overall size of the electric compressor 1, compared with the case where the entire length is set to 510 mm. In addition, the longitudinal wall portion 42 in the long-side direction can be retained, and the sealing performance with the inverter housing 8 at this portion can be maintained.

[0058] In addition, in the above-mentioned embodiments, both the curvature radii R1 and R2 of the arched portion of the upper wall portion 41 of the cover 15 and the rising angle X1 of the longitudinal wall portion 42 are adjusted, but the natural vibration frequency of the cover 15 can also be deviated from the resonance point with the compression mechanism 4 and the excitation force of the electric motor 2 by adjusting only any one of them.

[0059] In addition, in each embodiment, the natural vibration frequency of the cover 15 is set to a range higher than the frequency of the excitation force of the compression mechanism 4 and the electric motor 2, but the present invention is not limited thereto, and the natural vibration frequency of the cover 15 may be set to a range lower than the frequency of the excitation force of the compression mechanism 4 and the electric motor 2. In this case, although temporary resonance occurs at the time of starting / stopping, the occurrence of resonance can be suppressed as a whole.

[0060] Furthermore, in the above-mentioned embodiment 2, the composite shape of the rotating curved surface and the circular parabola is described, but in the case where the shell shape of the cover 15 is composed of multiple arched portions with different curvature radii, multiple spherical shells can also be independently constructed on the upper wall portion 41, and they can be smoothly connected with curved surfaces such as hyperbolic paraboloids and cylindrical surfaces.

[0061] In addition, the scroll electric compressor is used as an example in the embodiment, but it can also be applied to other compression forms of the inverter integrated electric compressor. In addition, the shapes and values ​​shown in each embodiment are not limited to these, and various changes can be made without departing from the scope of the present invention. Description of reference numerals:

[0062] 1: inverter-integrated electric compressor; 2: electric motor (motor); 3: inverter; 4: scroll compression mechanism (compression mechanism); 7: stator housing; 8: inverter housing; 10: housing body; 11: housing; 13: inverter storage portion; 15: cover; 41: upper wall portion; 42: longitudinal wall portion; 46: sealing flange portion.

Claims

1. An inverter-integrated electric compressor, characterized in that: The inverter-integrated electric compressor comprises: a metal housing in which a motor and a compression mechanism are built; An inverter is used to drive the motor; an inverter storage portion is composed of the housing and stores the inverter; and a metal cover, closing the inverter storage portion, The cover is formed of a metal plate, and the metal plate has: a shell-shaped upper wall portion; a longitudinal wall portion formed continuously with the outer periphery of the upper wall portion; and a sealing flange portion extending continuously outward from the outer periphery of the longitudinal wall portion and mounted on the outer shell, By adjusting the radius of curvature of the shell-shaped arched portion constituting the upper wall portion and / or the angle at which the vertical wall portion rises from the sealing flange portion, the natural vibration frequency of the cover is deviated from the resonance point with the excitation force of the compression mechanism and the motor.

2. The inverter-integrated electric compressor according to claim 1, characterized in that: The radius of curvature of the arched portion of the cover has different values ​​in the long side direction and the short side direction.

3. The inverter-integrated electric compressor according to claim 2, characterized in that: The radius of curvature of the arched portion of the cover in the long side direction is greater than the radius of curvature in the short side direction.

4. The inverter-integrated electric compressor according to claim 1, characterized in that: The shell shape of the cover is composed of a plurality of arched portions with different curvature radii.

5. The inverter-integrated electric compressor according to any one of claims 1 to 4, characterized in that: The vertical wall portion rises at an angle of not less than 30° and not more than 75° from the sealing flange portion.

6. The inverter-integrated electric compressor according to any one of claims 1 to 4, characterized in that: The height dimension of the cover is not less than 8 mm and not more than 20 mm.

7. A method for manufacturing an inverter-integrated electric compressor, characterized in that: The inverter-integrated electric compressor comprises: a metal housing in which a motor and a compression mechanism are built; an inverter for driving the motor; an inverter storage portion, formed by the housing, storing the inverter; and a metal cover, closing the inverter storage portion. The manufacturing method of the inverter-integrated electric compressor is as follows: The cover is formed by a metal plate, and the metal plate includes: a shell-shaped upper wall portion; a vertical wall portion formed continuously with the outer periphery of the upper wall portion; and a sealing flange portion extending continuously outward from the outer periphery of the vertical wall portion and mounted on the outer shell, The natural vibration frequency of the cover is deviated from the resonance point with the excitation force of the compression mechanism and the motor by adjusting the curvature radius of the shell-shaped arched portion constituting the upper wall portion and / or the angle at which the vertical wall portion rises from the sealing flange portion.

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