Electric compressor

Abstract

To provide an electric compressor excellent in airtightness of a storage chamber and electromagnetic countermeasures to an inverter while achieving miniaturization.SOLUTION: In an electric compressor of the present invention, a cover 7 is fixed to a housing 1 by fixtures 31a-31f. The housing 1 and the fixtures 31a-31f are made of metal. The cover 7 is formed of a vibration-damping steel plate 70. The vibration-damping steel plate 70 includes a first steel plate 71, a second steel plate 72, and a resin material 73. The cover 7 is fixed to the housing 1, and thereby, the fixtures 31a-31f come into contact with the first steel plate 71. The second steel plate 72 has a second surface 72b facing the housing 1. The second surface 72b has first portions 711-716 and second portions 721-726. A gasket 33 seals between the second portions 721-726 and the housing 1. At least one of the first portions 711-716 is directly brought into contact with the housing 1.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to an electric compressor.

Background Art

[0002] Patent Document 1 discloses a conventional electric compressor. This electric compressor includes a compression mechanism, an electric motor, an inverter, a housing, and a cover. The compression mechanism compresses a fluid. The electric motor drives the compression mechanism. The inverter controls the driving of the electric motor. The housing houses the compression mechanism and the electric motor inside. The cover is fixed to the housing by a plurality of fixtures, and forms a housing chamber for housing the inverter between the cover and the housing.

[0003] The cover is made of an aluminum alloy. The cover has a first surface and a second surface. The first surface faces the outside of the cover. The second surface is located on the opposite side of the first surface and faces the inverter in the housing chamber. A plurality of ribs protruding toward the inverter are provided on the second surface. Further, a plurality of insertion holes are formed in the cover. Each insertion hole penetrates from the first surface to the second surface in the axial direction of the fixture. Each fixture is inserted into each insertion hole.

[0004] In this type of electric compressor, during operation, vibrations generated by the compression mechanism and the electric motor are transmitted to the housing, causing the housing to vibrate. Then, the vibration of the housing is transmitted to the cover, and the vibration of the cover increases the noise during operation. In this regard, in the electric compressor described in Patent Document 1, the rigidity of the cover is improved by each rib, thereby suppressing the vibration of the cover during operation.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, higher quietness is required for an electric compressor. Therefore, in the above conventional electric compressor, it is conceivable to suppress the vibration of the cover during operation by increasing the plate thickness of the cover and making the rigidity of the cover higher. However, in this case, since the cover becomes larger, the electric compressor becomes larger.

[0007] In addition, for an electric compressor, high airtightness with respect to the accommodation chamber is required to protect the inverter from water, dust, etc. Further, for an electric compressor, electromagnetic countermeasures are also required to minimize the influence of external noise on the inverter and to minimize the influence of the noise generated by the inverter on external devices.

[0008] The present invention has been made in view of the above conventional circumstances, and an object to be solved is to provide an electric compressor that achieves miniaturization, has excellent airtightness of the accommodation chamber, and has excellent electromagnetic countermeasures against the inverter.

Means for Solving the Problems

[0009] The electric compressor of the present invention includes a compression mechanism that compresses a fluid, an electric motor that drives the compression mechanism, an inverter that controls the drive of the electric motor, a housing that houses the compression mechanism and the electric motor therein, and a cover that is fixed to the housing by a plurality of fixtures and forms an accommodation chamber that houses the inverter between the cover and the housing, and is an electric compressor, wherein the housing and each of the fixtures are made of metal, the cover is made of a vibration-damping steel plate having a first steel plate, a second steel plate disposed axially spaced apart from the first steel plate with respect to the fixture, and a resin material provided between the first steel plate and the second steel plate, The cover is formed with a plurality of insertion holes that penetrate in the axial direction from the first steel plate to the second steel plate and through which the respective fixtures are inserted. The housing is formed with a plurality of fixing holes that face the respective insertion holes and through which the respective fixtures are inserted and fixed. By fixing the cover to the housing, each of the fixtures abuts against the first steel plate. The second steel plate has a first surface facing the resin material and a second surface located on the opposite side of the first surface in the axial direction and facing the housing when the cover is fixed to the housing. The second surface has a plurality of first portions in which the respective insertion holes open inward and a second portion located outside the respective first portions. The space between the second portion and the housing is sealed by a gasket. At least one of the first portions is in direct contact with the housing.

[0010] In the electric compressor of the present invention, the cover is made of a vibration-damping steel plate. This vibration-damping steel plate has a first steel plate, a second steel plate, and a resin material, and the resin material suppresses the transmission of vibration between the first steel plate and the second steel plate. Therefore, in this electric compressor, when suppressing the vibration of the cover during operation, it is not necessary to excessively increase the plate thickness of the cover.

[0011] Also, in this electric compressor, the second steel plate has a first surface and a second surface, and this second surface faces the housing when the cover is fixed to the housing by the respective fixtures. Further, the second surface has a plurality of first portions in which the respective insertion holes open inward and a second portion located outside the respective first portions. And the space between the second portion and the housing is sealed by a gasket. Therefore, in this electric compressor, it is possible to suitably prevent water, dust, etc. from entering the accommodation chamber from between the second portion and the housing.

[0012] Furthermore, in this electric compressor, the housing and each fixture are made of metal. When fixing the cover to the housing, each fixture is inserted into each fixing hole of the housing and fixed to the fixing holes. Also, each fixture abuts against the first steel plate by fixing the cover to the housing. And in this electric compressor, at least one of each first portion in the second steel plate is in direct contact with the housing. That is, at the location where the first portion and the housing are in direct contact, the second steel plate and the housing are in metal contact without an intervening gasket.

[0013] As a result, in this electric compressor, the cover and the housing can be preferably equipotentialized through the fixture. Therefore, in this electric compressor, the influence of external noise on the inverter can be minimized as much as possible, and the influence of the noise generated by the inverter on external devices during operation can be minimized as much as possible. Here, at the location where the first portion and the housing are in direct contact, even if no gasket is interposed, the metal contact between the first portion and the housing preferably seals both sides. For this reason, it is also possible to preferably prevent water, dust, etc. from entering the accommodation chamber from this location.

[0014] Therefore, the electric compressor of the present invention realizes miniaturization, has excellent airtightness of the accommodation chamber, and is excellent in electromagnetic countermeasures against the inverter.

[0015] In the electric compressor of the present invention, it is preferable that each first portion is in direct contact with the housing. In this case, the cover and the housing can be more preferably equipotentialized. Also, it is possible to more preferably prevent water, dust, etc. from entering the accommodation chamber from between the first portion and the housing.

[0016] The cover preferably covers a part of the housing from the outside in a state of being fixed to the housing. In this case, for example, compared with a configuration in which the housing covers a part of the cover from the outside in a state where the cover is fixed to the housing, the formation of the cover and the housing can be facilitated.

[0017] Also, in this case, the second surface may have a third portion that covers the outer peripheral surface of the housing while connecting to the second portion. And it is preferable that the space between the third portion and the housing is sealed by a gasket. Thereby, it is possible to suitably prevent water, dust, etc. from entering the accommodation chamber from between the third portion and the housing.

[0018] In the electric compressor of the present invention, the first steel plate may have a first plate body made of metal and a first plating layer that covers the first plate body. Also, the second steel plate may have a second plate body made of metal and a second plating layer that covers the second plate body. And it is preferable that the first plating layer and the second plating layer have corrosion resistance. In this case, since the first steel plate, the second steel plate, and thus the cover are less likely to corrode, the durability of the cover can be increased.

Advantages of the Invention

[0019] The electric compressor of the present invention achieves miniaturization, has excellent airtightness of the accommodation chamber, and is excellent in electromagnetic countermeasures against the inverter.

Brief Description of the Drawings

[0020]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0021] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The electric compressor of the embodiment is mounted on a vehicle (not shown) and constitutes a refrigeration circuit of a vehicle air conditioner.

[0022] As shown in FIG. 1, the electric compressor of the embodiment includes a housing 1, an electric motor 3, a compression mechanism 5, a cover 7, and an inverter 9. The housing 1 has a first housing 11 and a second housing 13.

[0023] In the present embodiment, the vertical direction and the front-rear direction of the electric compressor are defined by the respective arrows shown in FIG. 1. These vertical direction and front-rear direction are orthogonal to each other. And in FIGS. 2 and subsequent figures, the vertical direction and the front-rear direction are defined corresponding to FIG. 1. Note that these directions are an example for convenience of explanation, and the posture of the electric compressor is appropriately changed corresponding to the vehicle or the like on which it is mounted.

[0024] As shown in FIG. 1, the first housing 11 is made of an aluminum alloy. The first housing 11 has a bottom wall 11a, a first side wall 11b, and a second side wall 11c. The bottom wall 11a is located at the front portion of the first housing 11 and extends in the radial direction of the electric compressor. The first side wall 11b is continuous with the bottom wall 11a and extends in a cylindrical shape rearward in the axial direction of the electric compressor from the bottom wall 11a. With these bottom wall 11a and first side wall 11b, the first housing 11 forms a bottomed cylindrical shape with an open rear. A plurality of bolt holes 112 are formed in the first side wall 11b. Each bolt hole 112 opens at the rear end of the first side wall 11b and extends forward within the first side wall 11b. Note that in FIG. 1, one of the plurality of bolt holes 112 is shown.

[0025] Inside the first housing 11, a motor chamber 150 is formed by a bottom wall 11a and a first side wall 11b. The motor chamber 150 sucks refrigerant gas from outside the housing 1 through a suction port (not shown) formed in the first side wall 11b. That is, in this electric compressor, the motor chamber 150 also functions as a suction chamber for refrigerant gas. The refrigerant gas is an example of the "fluid" in the present invention. Further, a support portion 15 protruding into the motor chamber 150 is formed on the bottom wall 11a. A drive shaft 29 is rotatably supported on the support portion 15 via a bearing 17.

[0026] The second side wall 11c is continuous with the bottom wall 11a on the side opposite to the first side wall 11b and extends cylindrically forward in the axial direction of the electric compressor from the bottom wall 11a. The second side wall 11c has a front end face 110 located at the front end.

[0027] Further, six fixing holes 19 are formed in the second side wall 11c. Each fixing hole 19 is arranged at a predetermined interval in the circumferential direction of the second side wall 11c so as to correspond to insertion holes 75a to 75f described later with respect to the second side wall 11c. Each fixing hole 19 opens to the front end face 110 of the second side wall 11c and extends rearward inside the second side wall 11c. Although detailed illustration is omitted, a thread groove is formed on the inner peripheral surface of each fixing hole 19. Also, in the second side wall 11c, the portion where each fixing hole 19 is formed is formed with a thicker wall than other portions in the second side wall 11c. In FIG. 1 etc., one of the six fixing holes 19 is shown. Also, if there are a plurality of fixing holes 19, the number thereof can be designed appropriately.

[0028] The second housing 13 is also made of an aluminum alloy. The second housing 13 has a rear wall 13a and a third side wall 13b. The rear wall 13a is located at the rear end of the second housing 13 and extends in the radial direction of the electric compressor. A discharge port (not shown) is formed in the rear wall 13a.

[0029] The third side wall 13b is continuous with the rear wall 13a and extends forward from the rear wall 13a. The rear wall 13a and the third side wall 13b form the second housing 13 into a bottomed cylindrical shape with an open front.

[0030] The second housing 13 is disposed behind the first housing 11, and the front end of the third side wall 13b is in contact with the rear end of the first side wall 11b of the first housing 11. The first housing 11 and the second housing 13 are fastened to each other by inserting a plurality of bolts 111 into bolt holes 112 and fixing them to the bolt holes 112. Thereby, the first housing 11 and the second housing 13 are integrated. Although detailed illustration is omitted, a discharge chamber is formed in the second housing 13, and this discharge chamber communicates with a discharge port. Note that the first and second housings 11 and 13 can also be formed of a metal other than an aluminum alloy. Also, in FIG. 1, one of the plurality of bolts 111 is illustrated.

[0031] The electric motor 3 is housed in the motor chamber 150 of the first housing 11. The electric motor 3 has a stator 25, a rotor 27, a drive shaft 29, and a connection portion (not shown). The stator 25 is fixed to the inner peripheral surface of the first side wall 11b in the motor chamber 150. The stator 25 has a coil (not shown). The rotor 27 is disposed inside the stator 25. The drive shaft 29 is fixed to the rotor 27 and rotates integrally with the rotor 27. The connection portion is connected to a cluster block.

[0032] The compression mechanism 5 is housed behind the electric motor 3 within the first housing 11. As the compression mechanism 5, a known scroll type compression mechanism is adopted. The compression mechanism 5 has a fixed scroll fixed to the inner peripheral surface of the first side wall 11b and a movable scroll arranged opposite to the fixed scroll. The movable scroll is connected to the drive shaft 29 in a power transmissible manner and is rotatable by the drive shaft 29. The fixed scroll and the movable scroll mesh with each other to form a compression chamber therebetween. The compression chamber communicates with the discharge chamber. Note that the illustrations of the fixed scroll, the movable scroll, and the compression chamber are all omitted. Also, as the compression mechanism 5, a vane type compression mechanism or the like may be adopted.

[0033] As shown in FIGS. 1 and 2, the cover 7 is arranged in front of the housing 1, more specifically, in front of the second side wall 11c of the first housing 11. The cover 7 is formed by subjecting a vibration damping steel plate 70 to press working. That is, the cover 7 is made of the vibration damping steel plate 70.

[0034] As shown in FIGS. 3 and 4, the vibration damping steel plate 70 is composed of a first steel plate 71, a second steel plate 72, and a resin plate 73. The resin plate 73 is an example of the "resin material" in the present invention. In the vibration damping steel plate 70, the first steel plate 71 and the second steel plate 72 are arranged spaced apart in the front-rear direction. And the resin plate 73 is arranged between the first steel plate 71 and the second steel plate 72.

[0035] The first steel plate 71 is composed of a first plate body 710a and a first plating layer 710b. The second steel plate 72 is composed of a second plate body 720a and a second plating layer 720b. The first plate body 710a and the second plate body 720a are made of steel. The first plate body 710a and the second plate body 720a are formed with the same plate thickness. The first plating layer 710b and the second plating layer 720b are formed of a zinc-nickel alloy. Thereby, the first plating layer 710b and the second plating layer 720b have corrosion resistance.

[0036] In the first steel plate 71, the entire first plate body 710a is covered by the first plating layer 710b. Similarly, in the second steel plate 72, the entire second plate body 720a is covered by the second plating layer 720b. Thereby, the first steel plate 71 and the second steel plate 72 have corrosion resistance. Note that the first plating layer 710b and the second plating layer 720b may be formed of other metals as long as they have corrosiveness.

[0037] The first steel plate 71 has a first surface 71a facing the outside and a second surface 71b located on the opposite side of the first surface 71a and facing the resin plate 73. The second steel plate 72 has a first surface 72a facing the resin plate 73 and a second surface 72b located on the opposite side of the first surface 72a and facing the outside. Here, the first surface 71a constitutes the outer surface of the vibration damping steel plate 70, and thus the outer surface of the cover 7. And the second surface 72b constitutes the inner surface of the cover 7. That is, the first surface 71a faces the rear of the cover 7, and the second surface 72b faces the first housing 11.

[0038] The resin plate 73 is formed by molding a resin having viscoelasticity into a plate shape. The resin plate 73 is formed to be thinner than the first steel plate 71 and the second steel plate 72. The resin plate 73 is adhered to the second surface 71b of the first steel plate 71 and also adhered to the first surface 72a of the second steel plate 72. In this way, the resin plate 73 is located between the first steel plate 71 and the second steel plate 72 and fixed to the first steel plate 71 and the second steel plate 72. As a result, in the vibration damping steel plate 70, the first steel plate 71, the resin plate 73, and the second steel plate 72 are integrated with the resin plate 73 sandwiched between the first steel plate 71 and the second steel plate 72. In FIGS. 3 and 4, for ease of explanation, the plate thicknesses of the first steel plate 71, the second steel plate 72, and the resin plate 73, including the thicknesses of the first plating layer 710b and the second plating layer 720b, are exaggerated in the illustration. Also, in FIG. 1, the illustration of the first steel plate 71, the second steel plate 72, and the resin plate 73 is omitted.

[0039] As shown in FIGS. 1, 2, and 5, the cover 7 has a main body portion 7a, an edge portion 7b, and a peripheral wall portion 7c. The main body portion 7a is located inside the edge portion 7b and protrudes forward from the edge portion 7b. In other words, in the cover 7, the portion that protrudes forward is the main body portion 7a.

[0040] The edge portion 7b is located outside the main body portion 7a and is connected to the main body portion 7a. And the edge portion 7b extends outward from the main body portion 7a in the radial direction of the cover while surrounding the main body portion 7a in the circumferential direction. Thereby, the edge portion 7b surrounds the main body portion 7a from the outside.

[0041] As shown in FIG. 5, insertion holes 75a to 75f are formed in the edge portion 7b. The insertion holes 75a to 75f are arranged at a predetermined interval in the circumferential direction of the edge portion 7b. The insertion holes 75a to 75f penetrate the edge portion 7b in the front-rear direction. That is, the insertion holes 75a to 75f extend from the first steel plate 71 through the resin plate 73 to the second steel plate 72.

[0042] The peripheral wall portion 7c is connected to the outermost side of the edge portion 7b, that is, the outer edge of the edge portion 7b. The peripheral wall portion 7c extends in a cylindrical shape rearward from the edge portion 7b along the outer edge of the edge portion 7b. Thereby, the peripheral wall portion 7c has a standing wall shape rising from the edge portion 7b. Also, as shown in FIG. 1, the peripheral wall portion 7c is formed to have a larger diameter than the second side wall 11c of the first housing 11.

[0043] As shown in FIG. 5, in the cover 7, the second surface 72b of the second steel plate 72 has first portions 711 to 716, second portions 721 to 726, third portions 731 to 736, and fourth portions 741 to 746.

[0044] The first portions 711 to 716 are each located at a portion that becomes the edge portion 7b on the second surface 72b. As shown by the broken lines in FIG. 5, the first portions 711 to 716 are each formed larger than the insertion holes 75a to 75f. And in the first portion 711, the insertion hole 75a opens to the inside. Similarly, in the first portion 712, the insertion hole 75b opens to the inside, and in the first portion 713, the insertion hole 75c opens to the inside. Also, in the first portion 714, the insertion hole 75d opens to the inside, in the first portion 715, the insertion hole 75e opens to the inside, and in the first portion 716, the insertion hole 75f opens to the inside. Thus, the first portions 711 to 716 each form an annular shape surrounding the insertion holes 75a to 75f from the outside.

[0045] The second portions 721 to 726 are portions that become the edge portion 7b on the second surface 72b and are located at positions outside the first portions 711 to 716. Specifically, the second portion 721 is located between the first portion 711 and the first portion 712 in the circumferential direction of the edge portion 7b, the second portion 722 is located between the first portion 712 and the first portion 713 in the circumferential direction of the edge portion 7b, and the second portion 723 is located between the first portion 713 and the first portion 714 in the circumferential direction of the edge portion 7b. Also, the second portion 724 is located between the first portion 714 and the first portion 715 in the circumferential direction of the edge portion 7b, the second portion 725 is located between the first portion 715 and the first portion 716 in the circumferential direction of the edge portion 7b, and the second portion 726 is located between the first portion 716 and the first portion 711 in the circumferential direction of the edge portion 7b.

[0046] Thus, in the portion that becomes the edge portion 7b on the second surface 72b, the first portions 711 to 716 and the second portions 721 to 726 are alternately located in the circumferential direction of the edge portion 7b.

[0047] Parts 3 (731 - 736) are located at the portion that becomes the peripheral wall portion 7c on the second surface 72b and are connected to the second parts 721 - 726. Specifically, part 3 (731) is located at the outer peripheral side of the second part 721 in the peripheral wall portion 7c and is connected to the second part 721. Part 3 (732) is located at the outer peripheral side of the second part 722 in the peripheral wall portion 7c and is connected to the second part 722. Part 3 (732) is located at the outer peripheral side of the second part 722 in the peripheral wall portion 7c and is connected to the second part 722. Part 3 (733) is located at the outer peripheral side of the second part 723 in the peripheral wall portion 7c and is connected to the second part 723. Part 3 (734) is located at the outer peripheral side of the second part 724 in the peripheral wall portion 7c and is connected to the second part 724. Part 3 (735) is located at the outer peripheral side of the second part 725 in the peripheral wall portion 7c and is connected to the second part 725. And part 3 (736) is located at the outer peripheral side of the second part 726 in the peripheral wall portion 7c and is connected to the second part 726.

[0048] Parts 4 (741 - 746) are located at the portion that becomes the peripheral wall portion 7c on the second surface 72b and are located at the outer peripheral side of the first parts 711 - 716. Specifically, part 4 (741) is located at the outer peripheral side of the first part 711 in the peripheral wall portion 7c, part 4 (742) is located at the outer peripheral side of the first part 712 in the peripheral wall portion 7c, and part 4 (743) is located at the outer peripheral side of the first part 713 in the peripheral wall portion 7c. Also, part 4 (744) is located at the outer peripheral side of the first part 714 in the peripheral wall portion 7c, part 4 (745) is located at the outer peripheral side of the first part 715 in the peripheral wall portion 7c, and part 4 (746) is located at the outer peripheral side of the first part 716 in the peripheral wall portion 7c.

[0049] In this way, in the portion that becomes the peripheral wall portion 7c on the second surface 72b, parts 3 (731 - 736) and parts 4 (741 - 746) are alternately located in the circumferential direction of the peripheral wall portion 7c.

[0050] As shown in Fig. 1, the cover 7 is disposed behind the second side wall 11c of the first housing 11 with the second surface 72b facing the second side wall 11c. And the edge 7b of the cover 7 is fastened to the second side wall 11c by the fixing bolts 31a to 31f shown in Fig. 2. In this way, the cover 7 is fixed to the housing 1. Details regarding the fixing of the cover 7 to the housing 1 will be described later.

[0051] The fixing bolts 31a to 31f are an example of the "fasteners" in the present invention. The fixing bolts 31a to 31f all have the same configuration. Hereinafter, the fixing bolt 31a shown in Fig. 4 will be described as an example. The fixing bolt 31a is made of metal and extends in the front-rear direction in the axial direction. That is, the axial direction of the fixing bolt 31 is parallel to the axial direction of the electric compressor.

[0052] The fixing bolt 31a has a head 310 and a threaded portion 311. The head 310 is located at the front end of the fixing bolt 31a. The head 310 is formed to have a larger diameter than the insertion holes 75a to 75f. The threaded portion 311 is integral with the head 310 and extends rearward in the axial direction from the head 310. The threaded portion 311 is formed to have a smaller diameter than the insertion holes 75a to 75f.

[0053] As shown in Fig. 1, when the edge 7b of the cover 7 is fixed to the second side wall 11c, the peripheral wall portion 7c is located outside the second side wall 11c. And the peripheral wall portion 7c covers a part of the second side wall 11c from the outside.

[0054] Moreover, an accommodation chamber 8 is formed between the cover 7 and the bottom wall 11a of the first housing 11. The accommodation chamber 8 is surrounded by the second side wall 11c and is blocked at the front by the main body portion 7a of the cover 7.

[0055] Also, as shown in FIGS. 1 and 3, between the cover 7 and the second side wall 11c, more specifically, between the second portions 721 to 726 of the second surface 72b and the front end surface 110 of the second side wall 11c, and between the third portions 731 to 736 of the second surface 72b and the outer peripheral surface of the second side wall 11c, are sealed by a gasket 33. The gasket 33 is formed by solidifying a liquid gasket 33a applied to the second surface 72b.

[0056] On the other hand, as shown in FIG. 4, between the first portions 711 to 716 of the second surface 72b and the front end surface 110 of the second side wall 11c, and between the fourth portions 741 to 746 of the second surface 72b and the outer peripheral surface of the second side wall 11c, there is no gasket 33.

[0057] The inverter 9 has a circuit board 9a and a plurality of semiconductors 9b provided on the circuit board 9a. The inverter 9 is housed in the housing chamber 8 with the circuit board 9a fixed to the bottom wall 11a. The inverter 9 has lead wires (not shown) connected to the circuit board 9a connected to the stator 25 through a cluster block and a connection portion. Thereby, the inverter 9 and the electric motor 3 are connected so as to be energizable. Also, the inverter 9 is connected to be energizable to a battery (not shown) of the vehicle.

[0058] In the electric compressor configured as described above, DC power is supplied from the battery to the inverter 9. Then, the inverter 9 converts the DC power into AC power and supplies the AC power to the electric motor 3 to control the drive of the electric motor 3. In the electric motor 3 to which the AC power is supplied, the rotor 27 and the drive shaft 29 rotate. Thereby, the compression mechanism 5 is driven. Thus, in the compression mechanism 5, the refrigerant gas sucked from the suction port is compressed and the compressed refrigerant gas is discharged from the discharge port.

[0059] And in this electric compressor, the cover 7 is fixed to the housing 1 as follows. First, as a preparation step, the cover 7 is prepared. Next, a coating step is performed, and a liquid gasket 33a is applied to a portion that becomes the edge 7b on the second surface 72b of the second steel plate 72.

[0060] Next, an assembling step is performed. In the assembling step, the cover 7 is disposed in front of the second side wall 11c with the second surface 72b facing the second side wall 11c of the first housing 11. Then, the edge 7b is brought into contact with the front end surface 110 of the second side wall 11c together with the liquid gasket 33a. Also, at this time, in the cover 7, the insertion holes 75a to 75f are aligned while being opposed to the respective fixing holes 19 of the first housing 11 in the front-rear direction. Thus, the assembling step is completed. Before the assembling step is completed, the circuit board 9a of the inverter 9 is fixed to the bottom wall 11a of the first housing 11.

[0061] Next, a fixing step is performed. In the fixing step, as shown in FIG. 2, with respect to the insertion hole 75a, the threaded portions 311 of the fixing bolts 31a to 31f are inserted from the front side of the cover 7, that is, from the side of the first steel plate 71. Then, each threaded portion 311 is screwed into the fixing hole 19. Taking the fixing bolt 31a as an example for specific explanation, as shown in FIG. 4, in the fixing bolt 31a, the threaded portion 311 is inserted from the insertion hole 75a into the fixing hole 19 of the first housing 11. Then, the threaded portion 311 is screwed into the fixing hole 19. Also, by screwing the threaded portion 311 into the fixing hole 19 in this way, in the fixing bolt 31a, the head 310 abuts against the first steel plate 71 around the insertion hole 75a.

[0062] Thus, by fixing the fixing bolts 31a to 31f to the respective fixing holes 19, the fixing step is completed. As a result, as shown in FIG. 1, the edge 7b of the cover 7 is fastened and fixed to the second side wall 11c in a state of being pressed against the front end surface 110 of the second side wall 11c from the front. And by fixing the edge 7b to the second side wall 11c in this way, the peripheral wall portion 7c of the cover 7 covers a part of the outer peripheral surface of the second side wall 11c from the outside.

[0063] Here, in this electric compressor, before the liquid gasket 33a applied to the second surface 72b in the coating process solidifies, the assembling process and the fixing process are completed. Taking the periphery of the insertion hole 75a on the second surface 72b as an example, as shown in FIG. 4, the liquid gasket 33a applied around the insertion hole 75a on the second surface 72b is drawn into the fixing hole 19 together with the threaded portion 311 of the fixing bolt 31a during the process of screwing the threaded portion 311 of the fixing bolt 31a into the fixing hole 19. As a result, in this electric compressor, there is almost no liquid gasket 33a around the insertion hole 75a on the second surface 72b, that is, in the first portion 711. Also, there is almost no liquid gasket 33a in the fourth portion 741 connected to the first portion 711. The same applies to the first portions 712 to 716 and the fourth portions 742 to 746.

[0064] On the other hand, as shown in FIG. 3, on the second surface 72b, in the second portions 721 to 726, there will be a liquid gasket 33a between the front end surface 110 of the second side wall 11c. Here, as described above, due to the fixing process, the edge portion 7b is fixed to the second side wall 11c in a state of being pressed against the front end surface 110 of the second side wall 11c from the front. Therefore, a part of the liquid gasket 33a existing between the second portions 721 to 726 and the front end surface 110 of the second side wall 11c will protrude into the third portions 731 to 736 connected to the second portions 721 to 726. For this reason, there will also be a liquid gasket 33a between the third portions 731 to 736 of the second surface 72b and the outer peripheral surface of the second side wall 11c. Also, a part of the liquid gasket 33a applied to the second surface 72b will protrude inside the second side wall 11c, that is, into the accommodation chamber 8.

[0065] Then, as the liquid gasket 33a solidifies to form the gasket 33, in this electric compressor, between the second portions 721 to 726 of the second surface 72b and the front end surface 110 of the second side wall 11c, and between the third portions 731 to 736 of the second surface 72b and the outer peripheral surface of the second side wall 11c are sealed by the gasket 33. On the other hand, there will be no gasket 33 between the first portions 711 to 716 and the front end surface 110 of the second side wall 11c, and between the fourth portions 741 to 746 and the outer peripheral surface of the second side wall 11c.

[0066] Also, as shown in FIGS. 3 and 4, in this electric compressor, the cover 7 is made of a vibration-damping steel plate 70. And in the vibration-damping steel plate 70, the resin plate 73 absorbs vibration energy between the first steel plate 71 and the second steel plate 72. Therefore, in this electric compressor, although the housing 1 inevitably vibrates during operation, in the cover 7, the transmission of vibration between the first steel plate 71 and the second steel plate 72 is suppressed. For this reason, in this electric compressor, even if vibration is transmitted from the housing 1 to the cover 7 during operation, the cover 7 is less likely to vibrate. Thus, in this electric compressor, when suppressing the vibration of the cover 7 during operation, it is not necessary to excessively increase the plate thickness of the cover 7.

[0067] Also, in this electric compressor, between the second portions 721 to 726 of the second surface 72b and the front end surface 110 of the second side wall 11c are sealed by the gasket 33. Further, between the third portions 731 to 736 of the second surface 72b and the outer peripheral surface of the second side wall 11c are also sealed by the gasket 33. Thereby, in this electric compressor, it is possible to preferably prevent water, dust, etc. from entering the accommodation chamber 8 between the second portions 721 to 726 and the front end surface 110 of the second side wall 11c, and between the third portions 731 to 736 and the outer peripheral surface of the second side wall 11c.

[0068] In addition, in this electric compressor, the first housing 11 and each of the fixing bolts 31a to 31f are made of metal. When fixing the edge 7b of the cover 7 to the second side wall 11c, each of the fixing bolts 31a to 31f is fixed to each fixing hole 19 of the second side wall 11c by screwing the screw portion 311 into the fixing hole 19. That is, by fixing the edge 7b to the second side wall 11c, in each of the fixing bolts 31a to 31f, the screw portion 311 contacts the second side wall 11c. Further, each of the fixing bolts 31a to 31f has a head 310 that abuts against the first steel plate 71 around the insertion holes 75a to 75f, respectively.

[0069] And as described above, in this electric compressor, there is no gasket 33 between the first portions 711 to 716 and the front end face of the second side wall 11c. Therefore, when the edge 7b is fixed to the second side wall 11c, each of the first portions 711 to 716 directly abuts against the front end face 110 of the second side wall 11c. That is, in the first portions 711 to 716, the second steel plate 72 and the second side wall 11c are in metal contact without the intervention of the gasket 33.

[0070] As a result, in this electric compressor, it is possible to preferably equalize the electric potential between the cover 7 and the first housing 11 through each of the fixing bolts 31a to 31f. Therefore, in this electric compressor, the influence of external noise on the inverter 9 can be minimized as much as possible, and the influence of the noise generated by the inverter 9 on external devices during operation can be minimized as much as possible. Here, even if the gasket 33 is not interposed between the first portions 711 to 716 and the front end face 110 of the second side wall 11c, the metal contact between the first portions 711 to 716 and the front end face 110 of the second side wall 11c preferably seals the space between them. Therefore, it is possible to preferably prevent water, dust, etc. from entering the accommodation chamber 8 from this location.

[0071] Therefore, the electric compressor of the embodiment realizes miniaturization, has excellent airtightness of the accommodation chamber 8, and is excellent in electromagnetic countermeasures against the inverter 9.

[0072] In particular, in this electric compressor, when fixing the cover 7 to the housing 1, the assembling process and the fixing process are completed before the liquid gasket 33a applied to the second surface 72b in the coating process solidifies. For this reason, by utilizing the screwing of the threaded portions 311 of the fixing bolts 31a to 31f into the respective fixing holes 19 and the fluidity of the liquid gasket 33a before solidification, the liquid gasket 33a can be made to be substantially absent from the first portions 711 to 716. As a result, in this electric compressor, it is not necessary to perform masking on the first portions 711 to 716 during the coating process so that the liquid gasket 33a is not applied to the first portions 711 to 716. For this reason, in this electric compressor, the coating process can be easily performed.

[0073] Also, by completing the assembling process and the fixing process before the liquid gasket 33a solidifies, the liquid gasket 33a protruding from the second portions 721 to 726 can preferably seal between the third portions 731 to 736 and the outer peripheral surface of the second side wall 11c by means of the gasket 33.

[0074] In addition, in this electric compressor, since the edge portion 7b of the cover 7 is fixed to the second side wall 11c, the peripheral wall portion 7c of the cover 7 is configured to cover a part of the outer peripheral surface of the second side wall 11c from the outside. As a result, for example, when the cover 7 is fixed to the second side wall 11c and the peripheral wall portion 7c enters the inside of the second side wall 11c, compared with a configuration in which the peripheral wall portion 7c is covered from the outside by the second side wall 11c, in this electric compressor, it is possible to facilitate the formation of the cover 7 and the second side wall 11c. Furthermore, since the peripheral wall portion 7c covers a part of the outer peripheral surface of the second side wall 11c from the outside, in this electric compressor, it is possible to easily provide the gasket 33 between the peripheral wall portion 7c and the second side wall 11c.

[0075] In addition, in this electric compressor, the first steel plate 71 and the second steel plate 72 of the vibration-damping steel plate 70 each have first and second plating layers 710b and 720b. As a result, since the first steel plate 71 and the second steel plate 72, and thus the cover 7, have corrosion resistance, the durability of this electric compressor is also high. Further, since the first steel plate 71 and the second steel plate 72 can be smoothed by the first and second plating layers 710b and 720b, respectively, it is possible to firmly fix the first steel plate 71 and the second steel plate 72 and the resin plate 73.

[0076] As described above, the present invention has been described with reference to the embodiments. However, the present invention is not limited to the above embodiments, and it goes without saying that the present invention can be appropriately modified and applied without departing from the gist thereof.

[0077] For example, in the electric compressor of the embodiment, each of the first portions 711 to 716 is in direct contact with the front end surface 110 of the second side wall 11c. However, the present invention is not limited to this, and at least one of the first portions 711 to 716 may be configured to be in direct contact with the front end surface 110 of the second side wall 11c.

[0078] Further, in the electric compressor of the embodiment, the gasket 33 between the peripheral wall portion 7c and the second side wall 11c may be omitted.

[0079] In addition, in the electric compressor of the embodiment, the fixing bolts 31a to 31f are used as the "fixing tool" in the present invention. However, the present invention is not limited to this, and a metal rivet or the like may be used as the "fixing tool" in the present invention.

[0080] In addition, in the electric compressor of the embodiment, the first steel plate 71 has a first plate body 710a and a first plating layer 710b, and the second steel plate 72 has a second plate body 720a and a second plating layer 720b. However, the present invention is not limited to this, and the first steel plate 71 and the second steel plate 72 may each be composed only of the first plate body 710a and the second plate body 720a formed of an alloy of zinc and aluminum.

[0081] In addition, in the electric compressor of the embodiment, masking may be performed on the first portions 711 to 716 during the coating process.

[0082] In the electric compressor of the embodiment, the refrigerant gas is used as the "fluid" in the present invention. However, it is not limited thereto, and air, oxygen, etc. may also be used as the "fluid" in the present invention.

[0083] In addition, this specification includes the following inventions. (Appendix 1) A compression mechanism for compressing a fluid, An electric motor for driving the compression mechanism, An inverter for controlling the drive of the electric motor, A housing for housing the compression mechanism and the electric motor therein, An electric compressor comprising a cover fixed to the housing by a plurality of fixtures and forming a housing chamber for housing the inverter between the cover and the housing, The housing and each of the fixtures are made of metal, The cover is made of a vibration-damping steel plate having a first steel plate, a second steel plate disposed axially spaced from the first steel plate with respect to the fixture, and a resin material provided between the first steel plate and the second steel plate, A plurality of insertion holes are formed in the cover, penetrating in the axial direction from the first steel plate to the second steel plate, and each of the fixtures is inserted therethrough, A plurality of fixing holes are formed in the housing, facing the respective insertion holes and fixing the respective fixtures while being inserted therethrough, Each of the fixtures abuts against the first steel plate by fixing the cover to the housing, The second steel plate has a first surface facing the resin material and a second surface located on the opposite side of the first surface in the axial direction and facing the housing when the cover is fixed to the housing, The second surface has a plurality of first portions each having an insertion hole opening therein and a second portion located outside each of the first portions, Between the second part and the housing, it is sealed by a gasket. An electric compressor, characterized in that at least one of the first parts is in direct contact with the housing. (Appendix 2) The electric compressor according to Appendix 1, wherein each of the first parts is in direct contact with the housing. (Appendix 3) The electric compressor according to Appendix 1 or 2, wherein the cover covers a part of the housing from the outside in a fixed state to the housing. (Appendix 4) The second surface has a third part that covers the outer peripheral surface of the housing from the outside while connecting to the second part. The electric compressor according to Appendix 3, wherein between the third part and the housing, it is sealed by the gasket. (Appendix 5) The first steel plate has a first plate body made of metal and a first plating layer covering the first plate body. The second steel plate has a second plate body made of metal and a second plating layer covering the second plate body. The electric compressor according to any one of Appendices 1 to 4, wherein the first plating layer and the second plating layer have corrosion resistance.

Industrial Applicability

[0084] The present invention can be used in an air conditioner of a vehicle or the like.

Explanation of Reference Numerals

[0085] 1... Housing 3... Electric motor 5... Compression mechanism 7... Cover 8... Accommodation chamber 9... Inverter 31a~31f... Fixing bolts (fasteners) 33... Gasket 70... Vibration damping steel plate 71... First steel plate 72... Second steel plate 72a... First surface 72b…Second side 73…Resin plate (resin material) 75a~75f…Insertion holes 710a…First board body 710b…First plating layer 711~716…First part 720a…Second board body 720b…Second plating layer 721…726…Second part 731…736…Third part

Claims

1. A compressor mechanism for compressing a fluid, an electric motor for driving the compressor mechanism, an inverter for controlling the drive of the electric motor, a housing for accommodating the compressor mechanism and the electric motor therein, an electric compressor comprising a cover fixed to the housing by a plurality of fixtures and forming an accommodation chamber for accommodating the inverter between the cover and the housing, wherein the housing and each of the fixtures are made of metal, the cover is made of a vibration-damping steel plate having a first steel plate, a second steel plate disposed axially spaced apart from the first steel plate with respect to the fixtures, and a resin material provided between the first steel plate and the second steel plate, a plurality of insertion holes are formed in the cover, penetrating in the axial direction from the first steel plate to the second steel plate, and through which each of the fixtures is inserted, a plurality of fixing holes are formed in the housing, facing the respective insertion holes and through which each of the fixtures is inserted and fixed, each of the fixtures abuts against the first steel plate by fixing the cover to the housing, the second steel plate has a first surface facing the resin material and a second surface located on the opposite side of the first surface in the axial direction and facing the housing when the cover is fixed to the housing, the second surface has a plurality of first portions each having an inner opening of the respective insertion hole and a second portion located outside each of the first portions, a gasket seals between the second portion and the housing, at least one of the first portions directly abuts against the housing, characterized in that the electric compressor.

2. The electric compressor according to claim 1, wherein each of the first portions directly abuts against the housing.

3. The electric compressor according to claim 1 or 2, wherein the cover covers a part of the housing from the outside in a state of being fixed to the housing.

4. The second surface has a third portion that covers the outer peripheral surface of the housing from the outside while connecting to the second portion, the electric compressor according to claim 3, wherein a gasket seals between the third portion and the housing.

5. The first steel plate has a first plate body made of metal and a first plating layer covering the first plate body, the second steel plate has a second plate body made of metal and a second plating layer covering the second plate body, the electric compressor according to claim 1 or 2, wherein the first plating layer and the second plating layer have corrosion resistance.

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