JP3804589B2 - Electric compressor - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electric compressor in which a compression mechanism is operated by driving an electric motor.
[0002]
[Prior art]
Conventionally, as an electric compressor used in a vehicle air conditioner, for example, the one shown in FIG. 4 exists.
[0003]
That is, an electric motor unit 102 and a compression mechanism 103 that compresses the refrigerant by the electric motor unit 102 are accommodated in a compressor housing 101 that forms an outline of the electric compressor 100. A motor drive circuit 104 for driving the electric motor unit 102 is housed and attached to the outside of the compressor housing 101 in a case 107.
[0004]
The compressor housing 101 is provided with attachment portions 105 having bolt insertion holes 105a on the upper side and the lower side in the drawing. Each mounting portion 105 is fastened and fixed to a boss portion 201 provided in the engine 200 that is a traveling drive source of the vehicle by a bolt 106 inserted through the bolt insertion hole 105a.
[0005]
[Problems to be solved by the invention]
However, in the electric compressor 100, the motor drive circuit 104 (case 107) is mounted on the opposite side of the compressor housing 101 from the engine 200. Therefore, when the electric compressor 100 is attached to the engine 200, the degree of exposure of the case 107 in the engine room is increased. For this reason, when a peripheral device collides with the electric compressor 100 due to a traffic accident or the like, there is a problem that the case 107 receives the direct hit and the motor drive circuit 104 is damaged.
[0006]
The case 107 protrudes greatly outward from the compressor housing 101, and the case 107 has an angular outer shape. Therefore, the case 107 easily interferes with other devices adjacent to the electric compressor 100, and the degree of freedom of layout of devices (including the electric compressor 100) in the engine room is reduced.
[0007]
An object of the present invention is to provide an electric compressor capable of protecting a motor drive circuit from an externally applied impact and easily avoiding interference with adjacent devices.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, according to a first aspect of the present invention, a motor drive circuit for driving an electric motor is disposed in a portion of the compressor housing facing the mounting target. Therefore, when the electric compressor is attached to the attachment target, the motor drive circuit is arranged so as to be hidden between the compressor housing and the attachment target. Therefore, even if the peripheral device collides with the electric compressor due to an accident or the like, for example, the motor drive circuit can be protected from the impact caused by the collision. Further, the motor drive circuit is not mounted (projected) on the side opposite to the attachment target in the compressor housing, that is, the side facing the other adjacent device. For this reason, the electric compressor of the present invention can easily avoid interference with other adjacent devices, and contributes to increasing the degree of freedom of layout of devices including itself.
[0009]
According to a second aspect of the present invention, in the first aspect, on the outside of the compressor housing, a plurality of mounting portions for mounting the compressor housing to a mounting target are provided around the motor drive circuit. That is, in the state where the electric compressor is attached to the attachment target, the attachment portion of the compressor housing and the attached portion to which the attachment portion is attached are located on the side of the gap between the compressor housing and the attachment target, that is, the motor drive circuit. It will be arranged on the side of. Accordingly, the protection effect of the motor drive circuit against external impact is further enhanced.
[0010]
According to a third aspect of the present invention, in the first or second aspect, the motor drive circuit includes a substrate disposed on a peripheral wall surrounding the central axis of the electric compressor in the compressor housing, and a plurality of the motor drive circuits mounted on a surface on the central axis side of the substrate. It consists of various electrical parts.
[0011]
The following consideration is given to the arrangement of the electrical components on the substrate. That is, a low-size electrical component having a low height from the board is arranged at a position near the central axis of the electric compressor on the board. A high electrical component with a high height from the substrate is disposed at a position far from the central axis in the substrate. By arranging such electrical components, the motor drive circuit can be mounted on the compressor housing so that these electrical component groups are along the cylindrical surface of the peripheral wall.
[0012]
Therefore, the motor drive circuit can be disposed close to the central axis of the electric compressor by the amount of the electrical component group along the cylindrical surface of the peripheral wall. Accordingly, it is possible to keep the amount of the motor drive circuit popping out from the compressor housing low, and to embody the invention of claim 1 or 2, that is, the motor drive circuit in a narrow gap between the peripheral wall of the compressor housing and the mounting object. It becomes easy to arrange. Note that setting the gap between the peripheral wall of the compressor housing and the mounting target to be narrow will reduce the amount of electric compressor protruding from the mounting target, which also contributes to increasing the degree of freedom in equipment layout. .
[0013]
According to a fourth aspect of the present invention, in the third aspect, a housing portion is provided on the peripheral wall of the compressor housing. And in this accommodating part, the accommodation space of a motor drive circuit is formed so that the cylindrical surface of a surrounding wall may be followed. Therefore, the motor drive circuit accommodated in the accommodation space is arranged so that the electrical component group is along the cylindrical surface of the peripheral wall. That is, the motor drive circuit is arranged closer to the central axis of the electric compressor by the amount of the electric component group along the cylindrical surface of the peripheral wall. Therefore, the amount of protrusion of the accommodating portion from the compressor housing can be kept low, and the invention of claim 1 or 2 can be realized more easily.
[0014]
According to a fifth aspect of the present invention, in the fourth aspect, the bottom surface and the side surface of the housing space in the housing portion are provided by a compressor housing. Therefore, for example, the number of parts of the electric compressor is reduced as compared with a case where the housing portion is prepared completely separate from the compressor housing (see, for example, the case 107 in the prior art in FIG. 4). In addition, a highly rigid compressor housing surrounds the periphery of the motor drive circuit, and is effective in protecting the motor drive circuit against external impacts and the like.
[0015]
According to a sixth aspect of the present invention, in the fifth aspect, the electrical component is in contact with the bottom surface of the housing space via an insulating material. By bringing the electrical component into contact with the bottom surface of the housing space, for example, the motor drive circuit is more central than when securing an insulating space (in other words, a large space) between the electrical component and the bottom surface of the housing space. It can be placed close to the axis. Therefore, it is possible to further reduce the amount of protrusion of the motor drive circuit (accommodating portion) from the compressor housing. Further, as compared with the case where the insulating space is secured, the heat generated by the electrical components can be efficiently released to the compressor housing, and the motor drive circuit can be efficiently cooled.
[0016]
According to a seventh aspect of the present invention, in the fifth or sixth aspect, a metal lid member for providing a top surface in the accommodating space is joined and fixed to the compressor housing. An insulating material is interposed between the top surface of the accommodation space provided by the lid member and the motor drive circuit. When the lid member is made of metal, the motor drive circuit is encased in metal by a combination with a compressor housing that is generally made of metal. Therefore, the electromagnetic wave generated by the motor drive circuit can be prevented from leaking to the outside, which is an effective noise countermeasure for other electronic devices.
[0017]
In addition, interposing an insulating material between the motor drive circuit and the top surface of the housing space ensures, for example, an insulating space (in other words, a large space) between the motor drive circuit and the top surface of the housing space. Compared to the case, the top surface can be disposed close to the central axis, that is, the lid member can be disposed close to the central axis. Therefore, it is possible to further reduce the amount of protrusion of the accommodating portion from the compressor housing. Further, as compared with the case of securing the insulating space, the heat generated by the motor drive circuit can be efficiently released to the outside air through the lid member, and the motor drive circuit is efficiently cooled.
[0018]
According to an eighth aspect of the present invention, in any one of the first to seventh aspects, the attachment target is an engine that is a travel drive source of the vehicle. Therefore, by disposing the motor drive circuit in the portion of the compressor housing facing the engine, even if a peripheral device collides with the electric compressor due to a traffic accident or the like, the motor drive circuit can be protected from the impact caused by the collision. it can. Further, the problem that the motor drive circuit easily interferes with other adjacent devices can be solved, and the degree of freedom of layout of the devices (including the electric compressor) in the engine room is increased. In other words, the inventions of claims 1 to 7 are particularly effective in an embodiment of an electric compressor for a vehicle that is arranged in an engine room where devices are densely packed.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment in which the present invention is embodied in an electric compressor for a vehicle air conditioner will be described.
[0020]
(Electric compressor)
As shown in FIGS. 1 and 2, the compressor housing 11 that forms the outline of the electric compressor 10 includes two housing components, a first housing component 21 and a second housing component 22. The first housing component 21 has a bottomed cylindrical shape with a bottom formed on the left side of the cylindrical peripheral wall 23 in the drawing, and is manufactured by an aluminum alloy die casting. The second housing component 22 has a covered cylindrical shape with a lid on the right side of the drawing, and is manufactured by an aluminum alloy die casting. A sealed space 24 is formed in the compressor housing 11 by joining and fixing the first housing component 21 and the second housing component 22.
[0021]
As shown in FIG. 1, a rotary shaft 27 is rotatably supported by a first housing component 21 in the sealed space 24 of the compressor housing 11. The rotation center axis L of the rotating shaft 27 forms the center axis L of the electric compressor 10. The peripheral wall 23 of the first housing component 21 is disposed so as to surround the central axis L of the electric compressor 10. Most of the outer surface 23b of the peripheral wall 23 exists on the cylindrical surface R (see FIG. 3) centered on the central axis L. The cylindrical surface R symbolizing the cylindrical shape of the peripheral wall 23 forms the “cylindrical surface of the peripheral wall” in the present embodiment.
[0022]
An electric motor unit 25 as an electric motor and a compression mechanism 26 are accommodated in the sealed space 24 of the compressor housing 11. The electric motor unit 25 is a brushless DC type including a stator 25a fixed to the inner surface 23a of the peripheral wall 23 in the first housing component 21 and a rotor 25b provided on the rotating shaft 27 inside the stator 25a. The electric motor unit 25 rotates the rotating shaft 27 by receiving supply of electric power to the stator 25a.
[0023]
The compression mechanism 26 is of a scroll type including a fixed scroll 26a and a movable scroll 26b. The compression mechanism 26 compresses the refrigerant gas by turning the movable scroll 26b with respect to the fixed scroll 26a according to the rotation of the rotary shaft 27. Accordingly, when the compression mechanism 26 is operated by driving the electric motor unit 25, the low-temperature and low-pressure refrigerant gas from the external refrigerant circuit (not shown) is sucked into the suction port 31 (FIG. 2) formed in the first housing component 21. From the reference) and is sucked into the compression mechanism 26 via the electric motor unit 25. The refrigerant gas sucked into the compression mechanism 26 becomes a high-temperature and high-pressure refrigerant gas by the compression action of the compression mechanism 26 and is discharged from the discharge port 32 formed in the second housing structure 22 to the external refrigerant circuit.
[0024]
The refrigerant gas from the external refrigerant circuit is introduced into the compression mechanism 26 via the electric motor unit 25 by using the relatively low-temperature refrigerant gas and the electric motor unit 25 and later described. This is because the motor drive circuit 41 is cooled.
[0025]
(Motor drive circuit and its mounting structure)
As shown in FIGS. 2 and 3, in the first housing component 21, an accommodating portion 36 having an accommodating space 35 is provided in a part of the outer surface 23 b of the peripheral wall 23. The accommodating portion 36 includes a frame-shaped side wall portion 37 that is integrally extended from the outer surface 23 b of the peripheral wall 23, and a lid member 38 that is nipped and fixed to the front end surface of the side wall portion 37 using the attachment frame 40. ing. The lid member 38 is made of a thin metal plate such as an aluminum alloy. A seal member 39 for sealing the accommodation space 35 is interposed between the distal end surface of the side wall portion 37 and the outer peripheral edge portion of the lid member 38.
[0026]
As shown in FIG. 3, the bottom surface (the left side surface in FIG. 3) 35 a of the housing space 35 is formed by the outer surface 23 b of the peripheral wall 23, and the side surface (upper and lower surface in FIG. 3) 35 b of the housing space 35 is An inner surface of the side wall 37 is formed. That is, the bottom surface 35 a and the side surface 35 b of the accommodation space 35 are provided by the first housing component 21. The top surface (the surface on the right side in FIG. 3) 35 c of the accommodation space 35 is provided by a lid member 38.
[0027]
A motor drive circuit 41 for driving the electric motor unit 25 is housed in the housing space 35 of the housing unit 36. The motor drive circuit 41 includes an inverter and supplies power to the stator 25a of the electric motor unit 25 based on an external command from an air conditioner ECU (not shown).
[0028]
The motor drive circuit 41 includes a plurality of types of electric circuits mounted on a flat substrate 43, a surface 43a on the central axis L side of the electric compressor 10 on the substrate 43, and a surface 43b opposite to the central axis L. It consists of a part 44. The member number “44” of the electric parts is a generic name for electric parts 44A to 44E described later and other electric parts (not shown).
[0029]
The substrate 43 is fixed to the peripheral wall 23 by bolts or the like (not shown). Examples of the electrical component 44 include well-known components forming an inverter, that is, a switching element 44A, an electrolytic capacitor 44B, a transformer 44C, a driver 44D, a fixed resistor 44E, and the like. The driver 44D is an IC chip that intermittently controls the switching element 44A based on a command from the air conditioner ECU.
[0030]
In the surface 43b opposite to the central axis L side in the substrate 43, the height from the substrate 43 (height from the surface 43b) is assumed to be the height of the switching element 44A (disposed on the surface 43b). Only electrical components 44 lower than (height) are arranged. Examples of the electrical component 44 whose height from the substrate 43 is lower than the switching element 44A include a driver 44D and a fixed resistor 44E.
[0031]
On the surface 43a on the side of the central axis L in the substrate 43, the switching element 44A and the electrical components 44 whose heights (height from the surface 43a) h1 and h2 from the substrate 43 are higher than the height h3 of the switching element 44A. And are arranged. Examples of the electrical component 44 whose height from the substrate 43 is higher than that of the switching element 44A include an electrolytic capacitor 44B and a transformer 44C. Therefore, as far as the surface 43a on the central axis L side of the substrate 43 is concerned, the switching element 44A can be grasped as a small electrical component having a low height h3 from the substrate 43, and the electrolytic capacitor 44B and the transformer 44C. Can be grasped as a high-size electrical component having high heights h1 and h2 from the substrate 43.
[0032]
In the present embodiment, the following consideration is given to the arrangement of the electrical components 44 mounted on the surface 43a on the central axis L side of the substrate 43.
That is, on the surface 43 a of the substrate 43, a low-dimensional electrical component such as the switching element 44 </ b> A is disposed in the central portion near the central axis L. On the surface 43 a of the substrate 43, high-sized electrical components such as an electrolytic capacitor 44 </ b> B and a transformer 44 </ b> C are arranged on both sides (upper and lower sides in FIG. 3) of the central portion away from the central axis L. With this arrangement, the motor drive circuit 41 can be mounted on the compressor housing 11 such that the group of electrical components 44 mounted on the surface 43a side of the substrate 43 is along the cylindrical surface R of the peripheral wall 23. It is.
[0033]
Although not shown, a plurality of the switching elements 44A, electrolytic capacitors 44B, and transformers 44C are arranged in the front and back direction in FIG.
In the housing space 35 of the housing portion 36, the distance between the bottom surface 35a and the top surface 35c is narrow at the center portion corresponding to the low-size electrical component such as the switching element 44A. In the accommodation space 35, the space between the bottom surface 35a and the top surface 35c is wide on both sides (upper and lower sides in FIG. 3) of the central portion corresponding to high-size electrical components such as the electrolytic capacitor 44B and the transformer 44C. That is, the bottom surface 35a of the accommodation space 35 has a convex shape that is closest to the top surface 35c at the center. Therefore, it can be said that the accommodation space 35 has a shape along the cylindrical surface R of the peripheral wall 23 as compared with an accommodation space in which the entire bottom surface 35a is planar, for example.
[0034]
Therefore, in the motor drive circuit 41 arranged in the accommodation space 35, the group of electrical components 44 on the surface 43 a side of the substrate 43 is along the cylindrical surface R of the peripheral wall 23. Therefore, the motor drive circuit 41 is arranged as close to the central axis L of the electric compressor 10 as the electrical component 44 group is along the cylindrical surface R of the peripheral wall 23.
[0035]
The cylindrical surface R of the peripheral wall 23 is not interfered by the electrical component 44 group on the surface 43a side until the distance h4 from the substrate 43 is lower than the height h1 of the electrolytic capacitor 44B which is the highest electrical component. It approaches the surface 43a of the substrate 43 (without crossing). That is, the motor drive circuit 41 is disposed closer to the central axis L of the electric compressor 10 as the cylindrical surface R of the peripheral wall 23 approaches the substrate 43 to a position h4 that is lower than the height h1 of the electrolytic capacitor 44B. Has been.
[0036]
In the present embodiment, “the group of electrical components 44 along the cylindrical surface R of the peripheral wall 23” means that the cylindrical surface R of the peripheral wall 23 is such that the distance h4 from the substrate 43 is at least lower than the height h1 of the electrolytic capacitor 44B. Means a state of approaching the surface 43a without being interfered by the electric component 44 group on the surface 43a side.
[0037]
In particular, in the present embodiment, the cylindrical surface R of the peripheral wall 23 has the group of electrical components 44 on the surface 43a side so that the distance h4 from the substrate 43 is lower than the height h2 of the transformer 44C, which is next higher than the electrolytic capacitor 44B. The surface 43a of the substrate 43 is approached without being interfered with. Therefore, the electrical component 44 group on the surface 43a side is more closely aligned with the cylindrical surface R of the peripheral wall 23, and the motor drive circuit 41 is arranged closer to the central axis L.
[0038]
In the motor drive circuit 41, the switching element 44A, the electrolytic capacitor 44B, and the transformer 44C are respectively provided on the bottom surface 35a of the accommodation space 35, that is, the first housing component 21 (aluminum) via a rubber or resin sheet 45 that is an insulating material. Made). As the sheet 45, a sheet having excellent elasticity and / or a sheet having excellent heat conductivity is used. In the accommodation space 35, between the top surface 35c provided by the lid member 38 and the motor drive circuit 41, rubber or resin as an insulating material is filled (indicated by “46”). As the filler 46, a material having excellent elasticity and / or a material having excellent heat conductivity is used.
[0039]
(Mounting structure of electric compressor)
As shown in FIGS. 1 to 3, a mounting portion 51 is integrally formed on the outer surface 23 b of the peripheral wall 23 in the first housing component 21. The attachment portion 51 is provided with a pair positioned on one side in the circumferential direction of the cylindrical surface R with respect to the motor drive circuit 41 and a pair positioned on the other side in the circumferential direction of the cylindrical surface R with respect to the motor drive circuit 41. It has been. That is, a plurality (four in the present embodiment) of the attachment portions 51 are provided around the motor drive circuit 41. A bolt insertion hole 51 a is formed through each attachment portion 51 so as to intersect the axis L of the rotation shaft 27 at a right angle. The bolt insertion holes 51a are parallel to each other.
[0040]
As shown in FIG. 3, the electric compressor 10 is attached to an engine 60 of a vehicle travel drive source, which is an external attachment target, with the attachment portion 51 described above. A boss portion 61 a as a mounted portion protrudes from a mounted surface 61 facing the peripheral wall 23 of the electric compressor 10 in the engine 60 at a position corresponding to the mounting portion 51 of the electric compressor 10. Each mounting portion 51 is joined and fixed to the boss portion 61a of the engine 60 by tightening the bolt 52 inserted through the bolt insertion hole 51a.
[0041]
When the electric compressor 10 is attached to the engine 60, the cylindrical surface R of the peripheral wall 23 of the first housing component 21 and the attached surface 61 of the engine 60 are separated from each other. That is, the attachment portion 51 and the boss portion 61a are designed such that the cylindrical surface R and the attachment surface 61 are separated from each other. The motor drive circuit 41 is mounted on the peripheral wall 23 of the first housing component 21 so as to be accommodated in a gap secured between the cylindrical surface R and the mounted surface 61. That is, it can be said that the motor drive circuit 41 is disposed in a portion facing the engine 60 in the peripheral wall 23 of the first housing component 21.
[0042]
Note that the portion of the peripheral wall 23 that faces the engine 60 specifically refers to a half-circumferential region of the cylindrical surface R on the engine 60 side. In the present embodiment, when the cylindrical surface R is viewed from the engine 60 side, the motor drive circuit 41 is configured to fit in the half-circumferential region of the cylindrical surface R on the engine side.
[0043]
In the present embodiment having the above-described configuration, the following effects are obtained.
(1) The motor drive circuit 41 is attached to a portion of the compressor housing 11 that faces the engine 60. Therefore, when the electric compressor 10 is attached to the engine 60, the motor drive circuit 41 is disposed so as to be hidden between the compressor housing 11 and the engine 60.
[0044]
Therefore, even if the degree of exposure in the engine room of the accommodating portion 36 that accommodates the motor drive circuit 41 decreases, for example, even if a peripheral device collides with the electric compressor 10 due to a traffic accident or the like, the accommodating portion 36. You can avoid direct hits. Therefore, the motor drive circuit 41 can be protected from the impact caused by the collision, and the motor drive circuit 41 can be prevented from being damaged.
[0045]
Further, the motor drive circuit 41 (accommodating portion 36) is not disposed (projected) on the side opposite to the engine 60 in the compressor housing 11, that is, on the side facing other adjacent devices. For this reason, the electric compressor 10 becomes easy to avoid interference with other adjacent devices, and contributes to increasing the degree of freedom in layout of devices (including the electric compressor 10) that are densely packed in the engine room.
[0046]
(2) A plurality of mounting portions 51 for mounting the compressor housing 11 to the engine 60 are provided around the motor drive circuit 41 outside the compressor housing 11. That is, in a state where the electric compressor 10 is attached to the engine 60, the attachment portion 51 of the compressor housing 11, the boss portion 61 a of the engine 60, and the bolt 52 that fastens and fixes both 51 and 61 are on the motor drive circuit 41 side. Will be placed in the direction. Therefore, the protection effect of the motor drive circuit 41 against external impacts and the like is further enhanced.
[0047]
(3) On the surface 43a on the side of the central axis L of the electric compressor 10 on the substrate 43, a low-size electrical component (such as a switching element 44A) is disposed at a position close to the central axis L. In addition, on the surface 43a of the substrate 43, a high-size electrical component (such as an electrolytic capacitor 44B or a transformer 44C) is disposed at a position far from the central axis L. With such an arrangement of the electrical components 44, the group of electrical components 44 on the surface 43 a side can be along the cylindrical surface R of the peripheral wall 23. A housing space 35 for the motor drive circuit 41 is formed in the housing portion 36 of the compressor housing 11 along the cylindrical surface R of the peripheral wall 23.
[0048]
Therefore, the motor drive circuit 41 accommodated in the accommodation space 35 is arranged such that the group of electrical components 44 on the surface 43 a side of the substrate 43 is along the cylindrical surface R of the peripheral wall 23. The motor drive circuit 41 can be disposed close to the central axis L of the electric compressor 10 by the amount of the electrical components 44 along the cylindrical surface R of the peripheral wall 23. Therefore, the amount of protrusion of the motor drive circuit 41 (accommodating portion 36) from the compressor housing 11 can be kept low, and the motor drive circuit 41 can be easily disposed in a narrow gap between the peripheral wall 23 of the compressor housing 11 and the engine 60. It becomes.
[0049]
It should be noted that setting the gap between the peripheral wall 23 of the compressor housing 11 and the mounted surface 61 of the engine 60 to be small suppresses the amount of the electric compressor 10 that protrudes from the engine 60, and this also occurs in the engine room. This contributes to increasing the degree of freedom of equipment layout.
[0050]
(4) In the housing portion 36, the bottom surface 35 a and the side surface 35 b of the housing space 35 are provided by the compressor housing 11. Therefore, for example, the number of parts of the electric compressor 10 can be reduced as compared with a case where an accommodating portion is prepared completely separate from the compressor housing 11 (see, for example, the case 107 in the prior art in FIG. 4). Further, the highly rigid compressor housing 11 (side wall 37) surrounds the periphery of the motor drive circuit 41, and is effective in protecting the motor drive circuit 41 against external impacts and the like.
[0051]
(5) The electric components 44 </ b> A to 44 </ b> C on the side of the central axis L in the substrate 43 are in contact with the bottom surface 35 a of the accommodation space 35 through the insulating sheet 45. When the electrical components 44A to 44C are brought into contact with the bottom surface 35a of the accommodation space 35, for example, an insulating space (in other words, a large space) is secured between the electrical components 44A to 44C and the bottom surface 35a of the accommodation space 35. In comparison, the motor drive circuit 41 can be arranged closer to the central axis L. Therefore, it is possible to further reduce the amount of protrusion of the motor drive circuit 41 (accommodating portion 36) from the compressor housing 11. Further, as compared with the case where the insulating space is secured, the heat generated by the electric components 44A to 44C can be efficiently released to the compressor housing 11, and the motor drive circuit 41 is efficiently cooled.
[0052]
Furthermore, if the sheet 45 is excellent in thermal conductivity, the motor drive circuit 41 described above can be cooled more efficiently. Further, if a sheet having excellent elasticity is used as the seat 45, it is effective for protecting the motor drive circuit 41 against an external impact or the like. Similarly, if a sheet having excellent elasticity is used as the sheet 45, the elastic deformation of the sheet 45 absorbs the dimensional tolerance, and the adhesion between the electrical components 44A to 44C and the bottom surface 35a of the accommodating space 35 is improved. This leads to an improvement in heat dissipation from the electrical components 44 </ b> A to 44 </ b> C to the compressor housing 11.
[0053]
(6) A metal lid member 38 for joining the compressor housing 11 to provide the top surface 35 c in the accommodation space 35 is joined and fixed. An insulating filler 46 is interposed between the top surface 35 c of the accommodation space 35 provided by the lid member 38 and the motor drive circuit 41. By making the lid member 38 made of metal, the motor drive circuit 41 is encased in metal by a combination with the compressor housing 11 which is also made of metal. Therefore, the electromagnetic wave generated by the motor drive circuit 41 can be prevented from leaking to the outside, which is an effective noise countermeasure for other electronic devices.
[0054]
Further, interposing the filler 46 between the motor drive circuit 41 and the top surface 35c of the accommodation space 35 is, for example, an insulating space (say, between the motor drive circuit 41 and the top surface 35c of the accommodation space 35). In other words, the top surface 35c can be disposed close to the central axis L, that is, the lid member 38 can be disposed close to the central axis L, compared to a case where a large space is secured. Accordingly, it is possible to further reduce the amount of protrusion of the accommodating portion 36 from the compressor housing 11. Further, as compared with the case of securing an insulating space, the heat generated by the motor drive circuit 41 can be efficiently released to the outside air through the lid member 38, and the motor drive circuit 41 is efficiently cooled. Become.
[0055]
Further, if the filler 46 having excellent thermal conductivity is used, the above-described cooling of the motor drive circuit 41 is performed more efficiently. Further, if a material having excellent elasticity is used as the filler 46, the motor drive circuit 41 can be protected against an external impact or the like. Similarly, if a material having excellent elasticity is used as the filler 46, the elastic deformation of the filler 46 absorbs the dimensional tolerance, and the adhesion between the motor drive circuit 41 and the lid member 38 is improved. This leads to an improvement in heat dissipation from the motor drive circuit 41 to the lid member 38.
[0056]
In addition, the following aspects can also be implemented without departing from the spirit of the present invention.
In the above embodiment, four attachment portions 51 are provided in the compressor housing 11. That is, for the attachment of the electric compressor 10 to the engine 60, four sets of attachment configurations including the attachment portion 51, the boss portion 61a, and the bolt 52 are provided. Change this, and install multiple sets other than 4 sets, such as 2 sets, 3 sets, 5 sets, or 6 sets of mounting configurations 51, 52, 61a. In addition, in order to stably fix the electric compressor 10 to the engine 60, at least three or more sets of mounting structures 51, 52, 61a are necessary. In balance between this stable fixing and the reduction in the number of parts. The four sets as in the above embodiment are ideal.
[0057]
In the above embodiment, the electric compressor 10 has the electric motor unit 25 and the compression mechanism 26 accommodated together in one compressor housing 11. By changing this, the electric compressor is embodied in the case where the electric motor and the compression mechanism are housed in separate compressor housings. In this case, the motor drive circuit may be mounted on the compressor housing that houses the electric motor, or may be mounted on the compressor housing that houses the compression mechanism.
[0058]
In the above embodiment, the electric compressor is embodied as a so-called full electric compressor in which the driving source of the compression mechanism 26 is only the electric motor unit 25. By changing this, the electric compressor is embodied as a so-called hybrid compressor using, for example, an engine that is a driving source of a vehicle as another driving source.
[0059]
-The compression mechanism 26 is not limited to a scroll type, For example, a piston type, a vane type, a helical type, etc. may be sufficient.
To describe the technical idea that can be grasped from the above embodiment, the motor drive circuit approaches the central axis as the cylindrical surface of the peripheral wall approaches the substrate to a position lower than the height of the high-size electrical component. The electric compressor according to any one of claims 3 to 7, wherein the electric compressor is arranged.
[0060]
【The invention's effect】
According to the present invention having the above-described configuration, it is possible to provide an electric compressor that can protect a motor drive circuit from an externally applied impact and can easily avoid interference with adjacent devices.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of an electric compressor.
FIG. 2 is a side view of the electric compressor.
3 is a cross-sectional view taken along line 1-1 of FIG. 2, and shows a state where an electric motor unit is removed.
FIG. 4 is a front view showing a conventional electric compressor.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Electric compressor, 11 ... Compressor housing, 23 ... Compressor housing peripheral wall, 25 ... Electric motor part as an electric motor, 26 ... Compression mechanism, 35 ... Storage space, 35a ... Bottom surface of storage space, 35b ... Side surface of storage space 35c: top surface of the housing space, 36: housing portion, 38: lid member, 41 ... motor drive circuit, 43 ... substrate, 43a ... surface on the central axis side of the substrate, 44A ... switching element as a low-size electrical component, 44B ... Electrolytic capacitor as high-size electrical component, 44C ... same transformer, 45 ... sheet as insulating material, 46 ... filling material as insulating material different from the above, 51 ... mounting part, 60 ... engine to be mounted, L: central axis of the electric compressor, R: cylindrical surface of the peripheral wall.

Claims (8)

An electric compressor in which a compression mechanism is operated by driving an electric motor, and a motor drive circuit for driving the electric motor is mounted on the outside of the compressor housing, and is configured to be attached to an external mounting target by the compressor housing In the electric compressor of
An electric compressor characterized in that the motor drive circuit is disposed in a portion of the compressor housing facing an attachment target. 2. The electric compressor according to claim 1, wherein a plurality of attachment portions for attaching the compressor housing to an attachment target are provided outside the compressor housing around the motor drive circuit. The motor drive circuit includes a substrate disposed on a peripheral wall surrounding the central axis of the electric compressor in the compressor housing, and a plurality of types of electrical components mounted on the surface on the central axis side of the substrate. By placing low-sized electrical components with a low height from the board at positions close to the central axis, and placing high-sized electrical components with a high height from the board at positions far from the central axis on the board, these The electric compressor according to claim 1, wherein the electric component group is configured to be along a cylindrical surface of the peripheral wall. The electric compressor according to claim 3, wherein a housing portion is provided on a peripheral wall of the compressor housing, and a housing space for a motor drive circuit is formed in the housing portion along the cylindrical surface of the peripheral wall. The electric compressor according to claim 4, wherein a bottom surface and a side surface of the storage space in the storage portion are provided by a compressor housing. The electric compressor according to claim 5, wherein the electric component is in contact with a bottom surface of the accommodation space via an insulating material. A metal lid member for providing a top surface in the accommodation space is joined and fixed to the compressor housing, and an insulating material is provided between the top surface of the accommodation space provided by the lid member and the motor drive circuit. The electric compressor according to claim 5 or 6, wherein is interposed. The electric compressor according to any one of claims 1 to 7, wherein the attachment target is an engine that is a driving source of a vehicle.

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