JP7263058B2 - electric compressor - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called inverter-integrated electric compressor in which an inverter is accommodated in an inverter accommodating portion formed in a housing.

Conventionally, in this type of inverter-integrated electric compressor, an inverter (inverter device) is accommodated and fixed in an inverter accommodating portion formed in a metal housing (accommodating portion main body), and the inverter accommodating portion is made of metal. was blocked by the cover of This cover is fixed with bolts at its periphery. However, since it vibrates and generates noise during operation, conventionally, a post for fixing the board is extended to the vicinity of the cover, and a restraint is provided between this post and the cover. Vibration is attenuated by sandwiching a vibration material (see, for example, Patent Document 1).

JP 2012-117445 A

However, in such a conventional structure, a strut structure must be formed in the housing for arranging the damping material between the cover and the cover. In addition, if a damping material is directly interposed between the substrate and the cover without adopting such a support structure, stress may be applied to the substrate and the substrate may be damaged.

SUMMARY OF THE INVENTION The present invention has been made to solve such conventional technical problems. And, it is an object of the present invention to provide an electric compressor that can be arranged without adversely affecting a substrate.

The electric compressor of the present invention includes a metal housing in which a motor is built, an inverter for driving the motor, an inverter accommodating portion configured in the housing and accommodating the inverter, and an inverter accommodating portion fixed to the housing to accommodate the inverter. The inverter has a board on which circuit elements are mounted, and this board is attached to the housing by bolts, and the cover is provided with a A protrusion projecting toward the substrate is integrally formed at a position where the bolt and the cover are located, and a vibration damping material is disposed between the bolt and the cover , and the vibration damping material is in contact with the protrusion of the cover. .

In the electric compressor of the invention of claim 2, in the above invention, the bolt has a head with a groove, the damping material abuts the head of the bolt, and the damping material has a recess avoiding the groove. A part is formed.

The electric compressor of the invention of claim 3 is characterized in that in each of the inventions described above, the damping material is arranged so as to surround the bolt.

The electric compressor of the invention of claim 4 is characterized in that in each of the above inventions, the damping material is made of an elastic material having insulating properties.

According to a fifth aspect of the present invention, there is provided an electric compressor in which the damping material is made of an elastic material having a hardness of 60 or more.

In the electric compressor of the invention of claim 6 , in each of the above inventions, the cover is fixed to the housing at the peripheral edge, and the damping material is in contact with the projecting part of the cover at a position spaced apart from the peripheral edge. characterized by

According to the present invention, a metal housing having a built-in motor, an inverter for driving the motor, an inverter accommodating portion configured in the housing and accommodating the inverter, and an inverter accommodating portion fixed to the housing are provided. In an electric compressor provided with a closing metal cover, an inverter has a board on which circuit elements are mounted, this board is attached to a housing by bolts, and a damping mechanism is provided between the bolts and the cover. Since the damping material is arranged, it is possible to interpose the damping material between the bolt and the cover to attenuate the vibration of the cover and reduce the noise without forming a special structure on the housing side.

In particular, since the bolts for fixing the board of the inverter to the housing can receive the vibration damping material, it is possible to avoid problems such as damage due to the load of the cover being applied to the board.

Furthermore, in the present invention, since the projecting portion projecting toward the substrate side is formed integrally with the cover at a position corresponding to the bolt, and the vibration damping material is brought into contact with the projecting portion of the cover, the vibration damping material can be easily covered. The load of the vibration damping material is stabilized by being able to abut on (the protrusion of) and also by improving the dimensional accuracy of the protrusion.

Here, when the damping material is arranged between the bolt and the cover, the damping material comes into contact with the head of the bolt. , there is a danger that strain will be concentrated on the damping material in the portion corresponding to this groove, and the damping material will be damaged. Such inconvenience can be eliminated by forming the relief portion.

Further, if the damping material is arranged so as to surround the bolt as in the invention of claim 3, the damping material can be positioned using the bolt, and the assembly workability is improved. improves.

Further, if the damping material is made of an insulating elastic material as in the fourth aspect of the present invention , the insulating property between the substrate and the cover is ensured.

Furthermore, by forming the damping material from an elastic material having a hardness of 60 or more as in the fifth aspect of the invention , it is possible to exert a sufficient vibration damping effect on the cover.

Furthermore, when the cover is fixed to the housing at the peripheral edge, if the vibration damping material is brought into contact with the projecting portion of the cover at a position spaced from the peripheral edge as in the sixth aspect of the invention , vibration of the cover can be suppressed. can be effectively damped by the damping material.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic longitudinal side view of the electric compressor of one Example to which this invention is applied. FIG. 2 is a plan view of the electric compressor of FIG. 1 with a cover removed, viewed from the inverter accommodating section side; FIG. 2 is an enlarged vertical cross-sectional side view of the portion of the inverter accommodating portion of the electric compressor of FIG. 1; FIG. 4 is an enlarged vertical cross-sectional view of a damping material portion of the inverter accommodating portion of FIG. 3 ;

An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a schematic vertical cross-sectional view of an electric compressor 1 of an embodiment to which the present invention is applied, FIG. 2 is a plan view of the electric compressor 1 with a cover 11 removed, viewed from the side of an inverter accommodating section 8, and FIG. 3 is an enlarged longitudinal side view of a portion of the inverter accommodating portion 8 of the electric compressor 1. FIG.

The electric compressor 1 of the embodiment is a so-called inverter-integrated electric compressor, and constitutes a part of a refrigerant circuit of a vehicle air conditioner that air-conditions the interior of a vehicle (not shown). The electric compressor 1 includes a motor 6, a metal housing 2 containing a compression mechanism 7 driven by a rotating shaft 5 of the motor 6, and an inverter 10 for driving the motor 6. 10 has an inverter circuit section 3 for control and a filter circuit section 4 for absorbing high frequency components of the switching current.

An inverter accommodating portion 8 is formed on the outer surface of the housing 2 of the embodiment at one end in the axial direction of the rotating shaft 5 of the motor 6 . is openable and closable by a metallic cover 11. The inverter circuit portion 3 and the filter circuit portion 4 that constitute the inverter 10 are accommodated in the inverter accommodating portion 8 so as to be detachably attached to the housing 2 . In each figure, the electric compressor 1 of the embodiment is shown with the inverter accommodating portion 8 facing upward, but in actuality, the inverter accommodating portion 8 is arranged laterally on one side. be.

The motor 6 of the embodiment is composed of a three-phase synchronous motor (brushless DC motor), and the compression mechanism 7 is, for example, a scroll compression mechanism. The compression mechanism 7 is driven by the rotary shaft 5 of the motor 6, compresses the refrigerant and discharges it into the refrigerant circuit. Low-temperature gas refrigerant sucked from an evaporator (also called a heat absorber), which also constitutes a part of the refrigerant circuit, flows through the housing 2 . Therefore, the inside of the housing 2 is cooled. The inverter housing portion 8 is separated from the housing 2 in which the motor 6 is housed by a partition wall 12 serving as the bottom surface of the inverter housing portion 8, and the partition wall 12 is also cooled by the low-temperature gas refrigerant.

The inverter circuit section 3 of the embodiment includes a power module 14 mounted with six power switching elements 13 (IGBTs in the embodiment) constituting arms of each phase of a three-phase inverter circuit, and a control circuit 16 as a circuit element. and an inverter control board (substrate) 17 on which is mounted, and a resin sleeve assembly 18 having a plurality of terminal connection portions 19, 20, 21, 22, and 23. As shown in FIG.

The inverter circuit unit 3 converts DC power supplied from a vehicle battery (not shown) into three-phase AC power and feeds the stator coil 27 of the motor 6 with the three-phase AC power. Therefore, the connection points between the power switching element 13 on the upper arm side and the power switching element 13 on the lower arm side of each phase are three motor side terminals 24, 25, and 26 drawn out from the partition wall 12 of the housing 2. The power supply terminal of the power switching element 13 on the upper arm side and the ground terminal of the power switching element 13 on the lower arm side are connected via the connection terminal 28 to connect the filter circuit section 4 and the high power connector (HV connector) 29 . It will be connected to the power supply harness from the battery mentioned above through.

In this case, the lead-out terminals 24 to 26 to which the connection points of the power switching element 13 on the upper arm side and the power switching element 13 on the lower arm side of each phase are connected pass through the partition wall 12 to the motor 6 in the housing 2. is connected to the stator coil 27 of the Further, the power supply terminal and the ground terminal are the filter circuit section 4, the power supply side connection terminals 31 respectively provided at the ends of the two wires 98 drawn out from the high power connector 29, and the high power connector. 29 or the like to the power supply harness.

The sleeve assembly 18 of the embodiment has the terminal connection portions 19 , 20 , 21 , 22 and 23 described above projecting therefrom, and the sleeve assembly 18 further has six sleeves 32 . The sleeve 32 is formed of a metal cylinder having a predetermined length, and the terminal connection portions 19 to 23 and the sleeve 32 are integrally molded with the sleeve assembly 18 with insulating hard resin. Each sleeve 32 is arranged on the periphery of the sleeve assembly 18, and its upper and lower ends are exposed and opened on the front and rear surfaces of the sleeve assembly 18 so that bolts 36 (36A) for fixing to the housing 2, which will be described later, can be inserted. be.

The filter circuit unit 4 includes circuit elements such as a relatively large smoothing capacitor 63 connected between the power supply terminal and the installation terminal of the three-phase inverter circuit and a relatively large coil 64 connected to the power supply terminal. It is composed of a mounted filter circuit board (substrate) 66 and a support member 67 made of hard resin that accommodates these capacitors 63 and coils 64 (circuit elements).

The support member 67 has a container (case) shape with one side open and a depth sufficient to accommodate the large smoothing capacitor 63 and the coil 64 as described above. 5 are formed of metal cylinders having a predetermined length and are molded integrally with the support member 67 with insulating hard resin. At one end of the support member 67, two bag-shaped metal nut members 69 for connecting the power supply side connection terminals 31 with bolts 93 are similarly resin-molded integrally with the support member 67. It is exposed at the surface of 67 and is open. Also, two filter-side connection terminals 71 are integrally molded with resin on the other end side of the support member 67 .

Such inverter circuit section 3 and filter circuit section 4 are attached to the housing 2 with a plurality of bolts 36, 36A (ten bolts in the embodiment). In this case, first, the inverter circuit portion 3 and the filter circuit portion 4 are accommodated in the inverter accommodating portion 8 of the housing 2 respectively. Then, the bolts 36 and 36A are inserted through the insertion holes (not shown) of the inverter circuit section 3 and the insertion holes (not shown) of the filter circuit section 4, and screwed into the screw holes 83 and 86 of the housing 2, respectively. The inverter circuit portion 3 and the filter circuit portion 4 of the inverter 10 are detachably attached to the housing 2 .

At this time, a bolt 36A positioned near the center of the inverter 10 (a bolt surrounded by a damping material 39, which will be described later and indicated by broken lines in FIGS. 1 and 2) is connected to the inverter control board 17 of the inverter circuit section 3 of the inverter 10. The filter circuit board 66 of the filter circuit section 4 is attached to the housing 2 by fastening together (Fig. 3). In this state, the terminal connection portions 19, 20 and 21 of the inverter circuit portion 3 are adjacent to the lead terminals 24, 25 and 26, respectively.

Next, each lead-out terminal 24, 25, 26 is press-fitted into one end of the three motor-side connection terminals 28, respectively. As a result, one end of each motor-side connection terminal 28 is press-contacted and electrically connected to each lead-out terminal 24-26. In addition, each terminal connection portion 19, 20, 21 is inserted into the other end of the motor-side connection terminal 28, and the lead terminal 24 and the terminal connection portion 19, the lead terminal 25 and the terminal connection portion 20, the lead terminal 26 and the terminal are connected with nuts. A motor-side connection terminal 28 is attached between the connection portions 21 .

As a result, each motor-side connection terminal 28 is fastened to each terminal connection portion 19 to 21 via the inverter control board 17 . In this manner, each motor-side connection terminal 28 is fixed and electrically connected to the inverter control board 17, and the lead-out terminals 24 to 26 from the motor 6 are electrically connected to the inverter control board 17 by the motor-side connection terminal 28. connect to.

Also, the terminal connection portions 22 and 23 of the inverter circuit portion 3 and the filter side connection terminal 71 are connected with nuts. As a result, the filter side connection terminal 71 is fixed and electrically connected to the inverter control board 17 , and the filter circuit board 66 of the filter circuit section 4 is electrically connected to the inverter control board 17 via the filter side connection terminal 71 . Connecting.

Finally, a plurality of mounting holes 41 are formed in the periphery of the opening 9 of the inverter housing portion 8 , and the cover 11 is attached to the opening 9 of the inverter housing portion 8 by bolts 43 screwed into the mounting holes 41 . In the present invention, bolts 36A are used in the inverter housing portion 8 between the cover 11 and the inverter 10 to close the opening 9 of the inverter housing portion 8 so as to be openable and closable. Vibration damping material 39 is arranged at the end.

Next, the damping material 39 provided in the inverter accommodating portion 8 will be described with reference to FIG. Note that the damping material 39 is indicated by broken lines in FIGS. Here, as described above, in the embodiment, the bolt 36A positioned near the center of the inverter 10 fixes the inverter control board 17 of the inverter circuit section 3 and the filter circuit board 66 of the filter circuit section 4 to the housing 2 by tightening them together. (Fig. 3). The bolt 36A is located near the center of the inverter housing portion 8 (that is, near the center of the cover 11) away from the peripheral portion of the opening 9 of the inverter housing portion 8. As shown in FIG. In this embodiment, a damping material 39 is arranged between the bolt 36A located near the center of the inverter accommodating portion 8 and the cover 11. As shown in FIG.

The vibration damping material 39 is formed by cylindrically molding an insulating elastic material, in this embodiment, an insulating rubber material such as EPDM, and has a hardness of 60 or higher. A recess 74 whose inner surface has substantially the same shape as the head 47 of the bolt 36A is formed on one surface of the damping material 39 in the axial direction (one surface on the bolt 36A side). is formed on the head 47 of the bolt 36A. A relief portion 82 for avoiding 81 is further recessed and formed.

On the other hand, at a position corresponding to the bolt 36A on the inner surface of the cover 11, a protruding portion 84 protruding toward the filter circuit board 66 is integrally formed. It is assumed to be a flat surface. When the cover 11 is attached to the housing 2, the axial dimension L1 of the damping material 39 is set to be smaller than the distance L2 between the projecting portion 84 and the filter circuit board 66 (see FIG. 4). , L1<L2).

The damping material 39 is attached to the bolt 36A before closing the inverter accommodating portion 8 with the cover 11. As shown in FIG. At that time, the head 47 of the bolt 36A is mounted in the recess 74 of the damping material 39 so that the head 47 of the bolt 36A is surrounded by the damping material 39 . Thereby, the damping material 39 is positioned.

Also, in this state, the head 47 of the bolt 36A abuts against the bottom surface of the recess 74 of the damping material 39. As shown in FIG. As described above, the axial dimension L1 of the damping material 39 is set smaller than the distance L2 between the projecting portion 84 and the filter circuit board 66. Therefore, when the cover 11 closes the inverter accommodating portion 8, the damping material The other surface of the damping material 39 in the axial direction contacts the projecting portion 84 , and one surface of the damping material 39 does not contact the filter circuit board 66 . The damping material 39 is interposed between the head 47 of the bolt 36A and the projecting portion 84 of the cover 11. As shown in FIG. In this state, the escape portion 82 formed in the recess 74 of the damping material 39 corresponds to the cross groove 81 of the head 47 of the bolt 36A, so the damping material 39 does not come into contact with the cross groove 81. .

In this manner, the filter circuit board 66 of the inverter 10 is attached to the housing 2 with the bolts 36A in the inverter accommodating portion 8, and the damping material 39 is arranged between the bolts 36A and the cover 11. Vibration damping material 39 is interposed between bolt 36A and cover 11 to attenuate vibration of cover 11 and noise can be reduced without forming a special structure on side 2.

In particular, since damping material 39 abuts head 47 of bolt 36A for fixing filter circuit board 66 of inverter 10 to housing 2, damping material 39 can be received by bolt 36A. That is, since the damping material 39 does not abut against the filter circuit board 66, the load of the cover 11 is applied to the filter circuit board 66, thereby avoiding problems such as breakage of the board 66.

Here, when the damping material 39 is arranged between the bolt 36A and the cover 11, the bottom surface of the recess 74 of the damping material 39 comes into contact with the head 47 of the bolt 36A. When the recess 74 of the damping material 39 abuts on the cross groove 81 formed in the head 47 of the bolt 36A, strain is concentrated in the portion of the damping material 39 corresponding to the cross groove 81, resulting in a damping. Although there is a risk that the damping material 39 may be damaged, in this embodiment, the bottom surface of the recess 74 of the damping material 39 is formed with an escape portion 82 that avoids the cross groove 81 of the head 47 of the bolt 36A. Inconvenience is eliminated.

Further, in the embodiment, since the damping material 39 is arranged so as to surround the bolt 36A, the damping material 39 can be positioned using the bolt 36A, and the assembly workability is improved. improves.

Furthermore, in this embodiment, since the projecting portion 84 projecting toward the filter circuit board 66 is formed integrally with the cover 11 at a position corresponding to the bolt 36A, the damping material 39 is brought into contact with the projecting portion 84 of the cover 11. As a result, the damping material 39 can be brought into contact with the cover 11 (protruding portion 84) without any trouble, and the dimensional accuracy of the projecting portion 84 is improved, thereby stabilizing the load of the damping material 39. .

Further, in the embodiment, the damping material 39 is made of an insulating elastic material, so that the insulation between the inverter control board 17 and the filter circuit board 66 of the inverter 10 and the cover 11 is ensured. .

Furthermore, in the embodiment, the vibration damping material 39 is made of an elastic material having a hardness of 60 or more, so that the cover 11 can exhibit a sufficient vibration damping effect.

Furthermore, in the embodiment, the cover 11 is fixed to the housing 2 at the peripheral portion, but the damping material 39 is brought into contact with the cover 11 (protruding portion 84) near the center spaced apart from the peripheral portion. , the vibration of the cover 11 can be effectively damped by the damping material 39 .

The shape/structure of the inverter 10 (the inverter circuit section 3 and the filter circuit section 4) and the housing 2 shown in the embodiment are not limited to them, and can be variously changed within the scope of the present invention. It goes without saying that it is.

REFERENCE SIGNS LIST 1 electric compressor 2 housing 3 inverter circuit section 4 filter circuit section 6 motor 8 inverter housing section 10 inverter 11 cover 12 partition wall 13 power switching element 14 power module 16 control circuit (circuit element)
17 Inverter control board (board)
36, 36A bolt 39 damping material 41 mounting hole 43 bolt 47 head 63 smoothing capacitor (circuit element)
64 coil (circuit element)
66 filter circuit board (substrate)
74 recess 81 cross groove (groove)
82 Escape portion 84 Projection portion

Claims (6)

a metal housing containing a motor; an inverter for driving the motor; an inverter accommodating portion configured in the housing to accommodate the inverter; In an electric compressor with a metal cover that
The inverter has a board on which circuit elements are mounted, and the board is attached to the housing with bolts,
The cover is integrally formed with a protruding portion protruding toward the substrate at a position corresponding to the bolt,
An electric compressor according to claim 1, wherein a damping material is arranged between the bolt and the cover , and the damping material abuts against the projecting portion of the cover . The bolt has a grooved head, and the damping material abuts the head of the bolt,
2. The electric compressor according to claim 1, wherein the damping material is formed with a relief portion that avoids the groove. 3. The electric compressor according to claim 1, wherein the damping material is arranged so as to surround the bolt. 4. The electric compressor according to claim 1, wherein the damping material is made of an insulating elastic material. 5. The electric compressor according to any one of claims 1 to 4, wherein the damping material is made of an elastic material having a hardness of 60 or more. The cover is secured to the housing at its peripheral edge, and
6. The electric compressor according to any one of claims 1 to 5, wherein the damping material abuts on the projecting portion of the cover at a position spaced apart from the peripheral portion.

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