CN111197577A

CN111197577A - Electric compressor

Info

Publication number: CN111197577A
Application number: CN201911126707.6A
Authority: CN
Inventors: 崔龙揆; 朴弘熙; 徐范准; 李丙哲
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2018-11-16
Filing date: 2019-11-18
Publication date: 2020-05-26
Also published as: US20200158108A1; KR102123970B1; KR20200057540A

Abstract

An electric compressor comprising: a housing provided with a motor chamber; a drive motor provided in the motor chamber of the housing and having a stator and a rotor; a rotating shaft coupled to the rotor; a first scroll provided at one side of the driving motor, having a rotation shaft which is axially penetrated and eccentrically coupled, and performing a revolving motion by the rotation shaft; a second scroll coupled to the first scroll to form a compression chamber together with the first scroll, the second scroll being rotatably inserted through a rotation shaft of the first scroll and coupled thereto; a rear housing disposed at one side of the second scroll and forming a discharge chamber together with the second scroll; a bearing portion provided at the second scroll or the rear housing, and radially supporting the rotary shaft; an oil supply guide passage provided in the second scroll or the rear housing and communicating the discharge chamber with the inside of the bearing portion; and a decompression member inserted into the oil supply guide passage and configured to decompress the pressure of the fluid passing through the oil supply guide passage. Thus, the pressure reducing flow path can be formed in a short and simple manner, and the pressure reducing effect can be improved.

Description

Electric compressor

Technical Field

The present invention relates to a MOTOR-driven electric compressor (MOTOR OPERATED CO mpresor).

Background

As an electric compressor, a scroll compression type electric compressor suitable for a high compression ratio operation is widely known. An electric compressor of a scroll system (hereinafter, simply referred to as an electric compressor) is configured such that an electric portion including a rotation motor is provided inside a sealed casing, a compression portion including a fixed scroll and an orbiting scroll is provided on one side of the electric portion, and the electric portion and the compression portion are connected by a rotation shaft to transmit a rotational force of the electric portion to the compression portion.

Such an electric compressor separates oil from a refrigerant discharged from a compression unit, and supplies a part of the separated oil to a back pressure chamber or a bearing surface. An example of the binarized oil supply passage is given in prior art 1[ japanese laid-open patent No. 2013-155643 (published date: 2013.08.15) ], and an example of the unified oil supply passage is given in prior art 2[ japanese laid-open patent No. 2013-100812 (published date: 2013.05.23) ].

The electric compressor according to prior art 1 is configured as follows: a first oil supply passage through which oil stored in the oil storage unit is supplied to the main bearing and the sub-bearing after being decompressed by the back pressure spring plate; and a second oil supply passage through which oil in the compression chamber is supplied to the orbiting bearing through the orbiting scroll and then moved to the motor chamber through the back pressure chamber.

The electric compressor according to prior art 2 is configured with one oil supply passage for supplying oil to the orbiting bearing in the compression chamber or the discharge chamber, supplying oil to the main bearing through the back pressure chamber, supplying oil to the sub-bearing through a passage inside the rotary shaft, and discharging the oil to the motor chamber.

In the electric compressor described above, oil is separated from the high-pressure refrigerant discharged from the compression chamber, and the separated high-pressure oil is supplied to the bearing or the back pressure chamber, and the oil is supplied after being decompressed to an appropriate pressure before being supplied to the bearing or the back pressure chamber. For this reason, the oil supply passage is formed long so that oil is decompressed through the long oil supply passage, or the oil supply passage is formed in the ring so that oil is decompressed through the oil supply passage provided to the convolution.

However, in the conventional electric compressor as described above, when the oil supply passage is formed long, the oil supply passage is formed in a complicated manner, and oil cannot be quickly supplied to the bearing surface or the back pressure chamber. Further, since the oil supply passages provided in the respective members need to communicate with each other, machining errors and assembly errors may occur, and it is difficult to form the oil supply passages. Further, when the machining or assembly of the oil supply passage is inconsistent, the oil supply passage is narrowed and clogged with impurities, so that the oil cannot be smoothly supplied. Further, when oil is not smoothly supplied to the bearing surface or the pressure distribution in the back pressure chamber is not uniform, the operation of the orbiting scroll becomes unstable and the compression efficiency is lowered.

In the conventional electric compressor, when the oil supply passage is formed in the orbiting scroll, oil is selectively introduced while the hard disk portions of the fixed scroll facing the orbiting scroll are attached to and detached from each other, and therefore, the oil is not rapidly supplied to the back pressure chamber, and the back pressure is unstable, which may lower the compression efficiency as described above. Further, since it is necessary to form an oil supply passage formed of a fine through hole in the convolution which requires relatively precise machining, there is a possibility that the convolution is deformed and the reliability of the compressor is lowered. Further, since the oil supply passage directly communicates with the compression chamber, the oil may flow back from the back pressure chamber to the compression chamber, and the effective volume of the compression chamber may be reduced, so that impurities in the back pressure chamber may easily flow into the compression chamber.

Disclosure of Invention

The purpose of the present invention is to provide an electric compressor capable of improving the pressure reduction effect while forming a pressure reduction flow path in a short and simple manner.

It is another object of the present invention to provide an electric compressor in which a decompression flow path is formed in one member, thereby preventing an excessive reduction in the cross-sectional area of the decompression flow path due to machining errors or assembly errors.

It is another object of the present invention to provide an electric compressor in which the effective length of a decompression passage is ensured to be constant, and the decompression effect is maintained to be constant, whereby the pressure in a back pressure chamber is maintained to be constant, the operation of an orbiting scroll is stabilized, and pressure loss can be suppressed.

Another object of the present invention is to provide an electric compressor in which a decompression flow path is always opened to rapidly and stably supply oil to a bearing surface, a compression chamber, or a back pressure chamber, thereby improving reliability and compression efficiency.

Further, it is an object of the present invention to provide an electric compressor capable of preventing a decompression flow path from being difficult to process an orbiting scroll or a fixed scroll and improving reliability.

It is another object of the present invention to provide an electric compressor capable of suppressing backflow of oil into a compression chamber through a decompression flow path.

Another object of the present invention is to provide a rotary shaft in which, when one end of the rotary shaft communicates with a discharge chamber, a large load is applied to the rotary shaft in the axial direction by oil of discharge pressure, and friction loss in the axial direction may increase. Accordingly, an object of the present invention is to provide an electric compressor capable of reducing a load applied in an axial direction, extending a life of an axial bearing, and reducing a friction loss in the axial direction.

Technical scheme for solving problems

In order to achieve the object of the present invention, there is provided an electric compressor in which a rotation shaft penetrates and is coupled to an orbiting scroll and a fixed scroll, and a bearing, which is rotatably inserted and supported in a radial direction, is coupled to the fixed scroll or is coupled to the fixed scroll on the opposite side of the orbiting scroll centering on the fixed scroll, the electric compressor including a housing, wherein an oil supply guide passage is formed to penetrate a side wall surface of the bearing portion in the radial direction to communicate with the inside of the bearing portion, a pressure reducing member is inserted into the oil supply guide passage, and the oil supply guide hole is formed to have a plurality of axial centers.

In order to achieve the above object, the present invention provides an electric compressor in which a rotary shaft penetrates through and is coupled to an orbiting scroll and a fixed scroll, the rotary shaft is coupled to the fixed scroll by a bearing rotatably inserted and radially supported, or coupled to the fixed scroll on the opposite side of the orbiting scroll centering on the fixed scroll, the electric compressor including a housing, wherein an oil supply guide passage is formed to penetrate through a side wall surface of a bearing portion in a radial direction to communicate with the inside of the bearing portion, a decompression member is inserted into the oil supply guide passage, and the decompression member is axially fixedly coupled to the oil supply guide passage.

In order to achieve the above object, the present invention provides an electric compressor in which a rotary shaft penetrates through and is coupled to an orbiting scroll and a fixed scroll, the rotary shaft is coupled to the fixed scroll by a bearing rotatably inserted and radially supported, or coupled to the fixed scroll on the opposite side of the orbiting scroll centering on the fixed scroll, the electric compressor including a housing, wherein an oil supply guide passage is formed to penetrate through a side wall surface of the bearing portion in a radial direction so as to communicate with the inside of the bearing portion, a decompression member is inserted into the oil supply guide passage, and a decompression passage is formed in the decompression member.

In order to achieve the object of the present invention, there is provided an electric compressor including: a housing provided with a motor chamber; a drive motor provided in the motor chamber of the housing, and having a stator and a rotor; a rotating shaft coupled to the rotor; a first scroll provided on one side of the drive motor, the rotation shaft penetrating in an axial direction and eccentrically coupled to the drive motor, the first scroll performing a revolving motion by the rotation shaft; a second scroll coupled to the first scroll to form a compression chamber together with the first scroll, the second scroll being rotatably inserted through a rotation shaft of the first scroll and coupled thereto; a rear housing provided on one side of the second scroll and forming a discharge chamber together with the second scroll; a bearing portion provided at the second scroll or the rear housing, and radially supporting the rotary shaft; an oil supply guide passage provided in the second scroll or the rear housing and communicating the discharge chamber with the inside of the bearing portion; and a decompression member inserted into the oil supply guide passage and configured to decompress the pressure of the fluid passing through the oil supply guide passage.

Here, an oil supply protrusion extending in a radial direction from the bearing portion may be formed, and the oil supply guide passage may be formed to penetrate in the radial direction in the oil supply protrusion.

The oil supply guide passage may have both ends open, a first end communicating with the discharge chamber may be formed with an oil supply inlet, a second end communicating with the inside of the bearing portion may be formed with an oil supply outlet, a decompression member housing portion into which the decompression member is inserted may be formed between the oil supply inlet and the oil supply outlet, a radial sectional area of the decompression member housing portion may be formed to be larger than a radial sectional area of the decompression member such that a decompression passage may be formed between an outer circumferential surface of the decompression member and an inner circumferential surface of the decompression member housing portion, and the oil supply inlet, the decompression member housing portion, and the oil supply outlet may be formed to be continuously communicated.

Here, the oil supply outlet may be formed eccentrically with respect to the decompression member accommodating portion.

Also, the axial length of the decompression member accommodating portion may be formed to be greater than the axial length of the decompression member.

Also, the axial length of the decompression member accommodating portion may be formed to be the same as the axial length of the decompression member.

Further, a decompression member support portion that supports the decompression member in an axial direction may be formed in a stepped manner between the oil supply outlet and the first end of the decompression member housing portion, and an axial center of the decompression member support portion may be formed eccentrically with respect to an axial center of the oil supply outlet.

Here, the oil supply outlet and the oil supply inlet may be formed on the same line in an axial direction.

Also, the decompression member may be inserted into and fixedly coupled to the decompression member accommodating portion.

The pressure reducing member may have a pressure reducing passage formed at a center portion thereof so as to axially penetrate therethrough, and the pressure reducing passage may communicate with the oil supply outlet.

The decompression member is formed of a material having a lower hardness than a member joined to the decompression member.

And, the decompression member may be formed with a support protrusion having one end expanded in a radial direction, and a support groove portion may be formed at an end of the oil supply inlet side of the decompression member accommodating portion so as to support the support protrusion in an axial direction, and the oil supply outlet and an end of the decompression member facing the oil supply outlet may be spaced apart from each other to form a communication space to communicate the decompression flow path and the oil supply outlet.

A communication space may be formed toward the oil outlet at an end of the decompression member facing the oil outlet.

Here, an impurity blocking member blocking impurities may be further provided at the oil supply guide flow path, the impurity blocking member forming a plurality of oil supply through holes.

The impurity blocking member may be formed to be positioned on the discharge chamber side with the decompression member as a center.

Also, the cross-sectional area of the oil feed through hole may be formed to be smaller than or equal to the cross-sectional area between the inner circumferential surface of the oil feed guide flow path and the outer circumferential surface of the decompression member.

Effects of the invention

The invention relates to an electric compressor, wherein an oil supply bulge with an oil supply guide flow path is formed on a fixed scroll or a rear shell forming a discharge chamber, a pressure reducing flow path is formed by inserting a pressure reducing member into the oil supply guide flow path, thereby forming the pressure reducing flow path in a short and simple way, and the length of the pressure reducing member and the cross section area of the pressure reducing flow path can be easily adjusted, thereby improving the pressure reducing effect.

Further, by forming the decompression flow path only on one side of the fixed scroll or the rear housing, it is possible to reduce machining errors and assembly errors, and thus it is possible to prevent the cross-sectional area of the decompression flow path from being excessively reduced, and it is possible to make the pressure distribution uniform while easily adjusting the degree of decompression.

Further, the inlet and the outlet of the oil supply guide passage are formed on both sides of the decompression member in the longitudinal direction, respectively, so that the effective length of the decompression passage is ensured to be constant, and the decompression effect is maintained to be constant, thereby the pressure of the back pressure chamber can be maintained to be constant. This stabilizes the operation of the orbiting scroll and prevents leakage between the compression chambers, thereby suppressing compression loss.

In the electric compressor according to the present invention, the outlet of the oil supply guide passage is formed eccentrically with respect to the decompression member housing portion, and thus the outlet of the oil supply guide passage and the decompression passage can be maintained in a state of always communicating with each other. This enables the oil to be supplied to the bearing surface or the compression chamber quickly and stably, thereby improving reliability and compression efficiency.

Further, the decompression passage is formed by inserting the decompression member into the oil supply guide passage, so that the orbiting scroll or the fixed scroll can be easily machined and the reliability of the drive between the scrolls on both sides can be improved.

In addition, the decompression flow path is separated from the compression chamber, thereby preventing oil from flowing back to the compression chamber through the decompression flow path.

In the electric compressor according to the present invention, the pressure reducing flow path is positioned in front of the oil accommodating space accommodating the rotary shaft, thereby reducing the axial load applied to the rotary shaft in the axial direction. This prevents the rotary shaft from being exposed to the discharge pressure, thereby reducing the load applied to the rotary shaft in the axial direction, extending the life of the bearing supporting the rotary shaft, and reducing the friction loss.

Drawings

Fig. 1 is a perspective view showing an external appearance of the electric compressor according to the present embodiment.

Fig. 2 is a perspective view illustrating the electric compressor of fig. 1 in an exploded manner.

Fig. 3 is a cross-sectional view showing the interior of the electric compressor according to fig. 1.

Fig. 4 is an exploded perspective view of the decompression device shown in fig. 3.

Fig. 5 is a sectional view showing the pressure reducing device according to fig. 4 in an assembled state.

Fig. 6 is a cross-sectional view taken along line "v-v" of fig. 5, which is a view for explaining the relative positions of the oil supply outlet and the pressure reducing member accommodating portion.

Fig. 7A is a schematic diagram illustrating the position of the decompression member during operation in the decompression device according to fig. 5.

Fig. 7B is a cross-sectional view taken along the line vi-vi of fig. 7A.

Fig. 8 is a sectional view showing another example of the decompression member according to fig. 3.

FIG. 9 is a cross-sectional view taken along the line "VII-VII" in FIG. 8.

Fig. 10 is a sectional view showing still another embodiment of the decompression member according to fig. 3.

FIG. 11 is a sectional view taken along the line "VIII-VIII" in FIG. 10.

Fig. 12 is a sectional view showing another example of the pressure reducing device according to the present invention.

FIG. 13 is a cross-sectional view taken along line IX-IX of FIG. 12.

Fig. 14 is a sectional view showing another example for fixing a decompression member in the decompression device according to the present invention.

FIG. 15 is a cross-sectional view taken along line "X-X" of FIG. 14.

Fig. 16 is a cross-sectional view showing an example in which the decompression member is in a free state in the decompression device according to the present invention.

Fig. 17 is a cross-sectional view taken along line XI-XI in fig. 16.

Fig. 18 is a sectional view showing an impurity blocking member provided at an oil supply inlet in the electric compressor according to the present invention.

Fig. 19 is a cross-sectional view showing an example in which the pressure reducing device according to the present embodiment is provided in the rear case.

Detailed Description

Hereinafter, an electric compressor according to the present invention will be described in detail with reference to an embodiment shown in the drawings.

Fig. 1 is a perspective view showing an external appearance of an electric compressor according to the present embodiment, fig. 2 is an exploded perspective view showing the electric compressor according to fig. 1, and fig. 3 is a cross-sectional view showing an interior of the electric compressor according to fig. 1.

Referring to these drawings, the scroll-type electric compressor (hereinafter, simply referred to as an electric compressor) driven by a motor according to the present embodiment is configured as follows: a compressor module 101 compressing a refrigerant; the inverter module 201 is coupled to the front side of the compressor module 101, and controls driving of the compressor module 101. The compressor module 101 and the inverter module 201 may be assembled in series or separately manufactured and assembled. The present embodiment is described with the latter as a representative example, but the compressor module and the inverter module may be independently manufactured and continuously assembled in a manner that the former and the latter are mixed.

The compressor module 101 includes: a main casing 110 having an inner space constituting a motor chamber S1, and having an air inlet 111 formed therein to communicate with the motor chamber; a drive motor 120 which is an electric unit fixed to the motor chamber S1 of the main casing 110; a compression unit 105 provided outside the main casing 110 on one side of the driving motor 120, for compressing the refrigerant by the rotational force of the driving motor 120; the rear case 160 is coupled to the other side of the compression portion 105 to form a discharge chamber S2.

As the main housing 110 is disposed transversely to the ground, the driving motor 120 and the compression part 105 are aligned in the transverse direction, and the driving motor 120 and the compression part 105 are disposed at the front side and the rear side, respectively. For convenience of explanation, the left side of fig. 3 is designated as the front side, and the right side is designated as the rear side.

The main housing 110 is formed in the shape of a cup section with an open front end and a closed rear end. An inverter case 210 described later is joined to and sealed at the open front end of the main case 110, and a frame portion 112 that supports the compression portion 105 is integrally formed to extend at the closed rear end of the main case 110. A first bearing portion 113 is formed in a cylindrical shape in the frame portion 112 of the main casing 110, and the first bearing portion 113 is rotatably supported by penetrating a main bearing portion 132 of a rotation shaft 130 described later.

The first bearing 171 formed of a bush bearing is inserted into and coupled to the first bearing portion 113, and an inner circumferential surface of the first bearing portion 113 and the main bearing portion 132 of the rotary shaft 130 are spaced from each other, so that a back pressure chamber S3 described later can communicate with the motor chamber S1. An air inlet 111 connected to an intake pipe (not shown) is formed near the front end of the main casing 110, so that the motor chamber S1 of the present embodiment forms an intake space. Therefore, in the electric compressor according to the present embodiment, the refrigerant is sucked into the compression portion through the internal space of the main casing constituting the motor chamber, thereby forming the low-pressure compressor.

As described above, the main casing according to the present embodiment is integrally formed with the frame portion. Thus, the process of assembling the frame to the main casing can be eliminated, the number of assembling steps can be reduced, and the assembling performance of the drive motor can be improved.

On the other hand, the driving motor 120 includes: a stator 121 inserted and fixed to an inner circumferential surface of the main casing 110; and a rotor 122 positioned inside the stator and rotated by interaction with the stator 121. A rotary shaft 130 is coupled to the rotor 122, and the rotary shaft 130 transmits the rotational force of the driving motor 120 to the compression part 105 while rotating together with the rotor 122.

The stator 121 is shrink-fitted (or hot-inserted) in the main housing 110 to fix the stator core 1211. Therefore, the insertion depth of the stator 121 in the main housing 110 is reduced, which not only facilitates the assembly work, but also can facilitate maintaining the concentricity of the stator 121 during the shrink-fitting of the stator 121.

In the center of the rotor 122, the rotation shaft 130 is coupled in a shrink fit (or shrink insertion) manner in the rotor core 1221. The rotation shaft 130 may support both ends in a radial direction between the driving motors 120. However, as described in the present embodiment, one end of the rotary shaft 130 may be a fixed end supported at two points in the radial direction on one side of the driving motor 120, that is, the frame portion 112 and the fixed scroll 150, and the other end of the rotary shaft 130 coupled to the rotor 122 of the driving motor 120 may be a free end.

The rotation shaft 130 is formed with: a shaft 131 coupled to the rotor 122; a main bearing portion 132 rotatably supported in the radial direction by the first bearing portion 113; an eccentric portion 133 eccentrically coupled to the orbiting scroll 140; the sub bearing 134 is rotatably supported in the radial direction by a second bearing 156 of the fixed scroll 150. As described above, the main bearing portion 132 and the sub bearing portion 134 support the rotation shaft 130 in the radial direction, respectively, the eccentric portion 133 transmits the rotation force of the driving motor 120 to the orbiting scroll 140, and the orbiting scroll 140 performs an orbiting motion by the oldham ring (oldham ring) 180.

Also, if referring to fig. 3, an axial bearing protrusion 135 may be formed to extend in a radial direction at the middle of the rotating shaft 130, i.e., between the main bearing part 132 and the eccentric part 133. The axial bearing surface 135a of the axial bearing protrusion 135 constitutes a thrust surface together with the axial bearing surface 113a of the first bearing portion 113.

A second oil supply guide passage 136 is formed in the rotary shaft 130 so as to be hollow at a predetermined depth in a direction from the rear end toward the front end, and

oil supply holes

137a, 137b, and 137c are formed in the middle of the second oil supply guide passage 136 toward the outer circumferential surfaces of the main bearing 132, the eccentric portion 133, and the sub bearing 134. In this regard, the following description will be made again together with the oil supply structure.

On the other hand, as described above, the compression unit 105 includes: an orbiting scroll (or, a first scroll) 140 axially supported to the frame 130 and performing an orbiting motion; and a fixed scroll (or, a second scroll) 150 engaged with the orbiting scroll 140 and fixedly coupled to a rear end of the frame 130. Between the orbiting scroll 140 and the fixed scroll 150, two pairs of compression chambers V are formed at the time of the orbiting motion of the orbiting scroll 140.

The orbiting scroll 140 is axially supported on the rear surface of the frame 130, and an oldham ring 180 as a rotation preventing mechanism for preventing the orbiting scroll 140 from rotating is provided between the frame 130 and the orbiting scroll 140. The oldham ring 180 is inserted into the oldham ring seating groove 133 of the frame 130, and the rotation preventing mechanism may be applied not only to the oldham ring but also to a pin and ring type.

The orbiting scroll hard plate portion (hereinafter, orbiting hard plate portion) 141 of the orbiting scroll 140 is formed in a substantially disk shape, and a orbiting ring 142 is formed on the front surface of the orbiting hard plate portion 141, and the orbiting ring 142 is engaged with a fixed ring 153 described later, and forms compression chambers V on the inner surface and the outer surface, respectively, with the fixed ring 153 as a reference.

The rotary hard plate portion 141 is provided with a back pressure hole 141a communicating the back pressure chamber S3 and the intermediate compression chamber V. Accordingly, oil or refrigerant moves between the back pressure chamber S3 and the intermediate compression chamber due to the difference between the pressure of the back pressure chamber S3 and the pressure of the intermediate compression chamber.

A rotation shaft coupling portion 143 is formed to penetrate through the center of the swing hard plate portion 141, and the eccentric portion 125d of the rotation shaft 125 is rotatably coupled to the rotation shaft coupling portion 143. The rotating shaft coupling portion 143 is formed in a cylindrical shape, and a third bearing 173 constituting a bearing surface with the eccentric portion 125d of the rotating shaft 125 is inserted into and coupled to the rotating shaft coupling portion 143. Thereby, the rotation shaft coupling portion (or the third bearing) 143 is formed to overlap the convolution 142 in the radial direction, and the rotation shaft coupling portion 143 becomes a part of the convolution 142 formed at the innermost side.

On the other hand, as described above, the fixed scroll 150 is coupled to the rear surface of the frame 130 outside the main casing 110. At this time, a sealing member such as an O-ring or a gasket may be disposed between the frame 130 and the fixed scroll 150.

The fixed scroll hard plate portion (hereinafter, fixed hard plate portion) 151 of the fixed scroll 150 is formed in a substantially disk shape, and a scroll side wall portion 152 coupled to a rear side support surface (hereinafter, simply referred to as a support surface) 130a of the frame 130 is formed at a front side edge position of the fixed hard plate portion 151.

The scroll side wall portion 152 is formed in an annular shape, an outer peripheral surface of the scroll side wall portion 152 forms an outer wall of the fixed scroll 150, and a front surface 152a of the scroll side wall portion 152 is coupled to the support surface 130a of the frame 130 via a seal member 108c described later. The scroll side wall portion will be described again together with the seal member.

A fixing ring 153 that engages with the circlip 142 to form the compression chamber V is formed on the front surface of the fixing hard plate 151. The fixing ring 153 and the rotating ring 142 may be formed in an involute shape together, but may be formed in other various shapes.

For example, when the rotating shaft 125 penetrates and is coupled to the center of the orbiting scroll 140, the fixed ring 153 and the orbiting ring 142 are finally formed at eccentric positions, and a large pressure difference is generated between the compression chambers. This is because, in the case of a scroll compressor in which the shaft penetrates, the final compression chamber is formed eccentrically from the center of the scroll, and the pressure in one compression chamber is greatly reduced relative to the pressure in the other compression chamber. Therefore, in the shaft penetration scroll compressor as described in the present embodiment, it is advantageous to form the rotation ring 142 and the fixed ring 153 in a non-involute shape.

The scroll side wall portion 152 is formed with a scroll side suction hole 154 that communicates with the frame side suction hole 135 of the frame 130 and guides the refrigerant to the suction chamber. In the case where the fixed ring 153 and the swing ring 142 are asymmetrical, the scroll-side suction hole 154 may be formed only one, but may be formed in plural in the case of being symmetrical as described in the present embodiment.

A discharge port 155 for guiding the discharge of the refrigerant by communicating the final compression chamber V with a discharge chamber S2 described later is formed in the central portion of the fixed hard plate portion 151. The discharge port 155 is formed to penetrate from the compression chamber V toward the discharge chamber S3 in the axial direction or the oblique direction of the fixed hard plate portion 151. The discharge port 155 may be formed in only one so as to communicate with both the first compression chamber and the second compression chamber, or may be formed in the first discharge port and the second discharge port so as to communicate with the first compression chamber and the second compression chamber independently.

A discharge valve 156 for opening and closing the discharge port 155 is provided on the rear surface of the fixed hard plate portion 151. In the case of a plurality of discharge ports 155, one discharge valve 156 may be provided, or a plurality of discharge valves may be integrally formed.

A second bearing portion 157 is formed at the center of the fixed hard plate portion 151 so that the sub-bearing portion 125c of the rotary shaft 125 is rotatably inserted and radially supported. The second bearing portion 157 may be formed to extend in the axial direction in the direction in which the fixed hard plate portion 151 faces the rear case 160, or may be formed to increase the thickness of the fixed hard plate portion 151. However, in the latter case, not only the weight of the fixed scroll 150 is increased, but also an unnecessary portion is formed thick, and the length of the discharge port 155 is increased, so that the slant volume is increased. Therefore, as described above, it is preferable that a part of the fixing hard plate portion 151 is protruded, and for example, the second bearing portion 157 is formed at a portion excluding a portion where the discharge port 155 is formed, so as to be protruded in the axial direction.

The second bearing portion 157 is formed in a cylindrical shape which is closed later, and a second bearing portion 172 which forms a bearing surface with the sub-bearing portion 125c of the rotary shaft 125 is inserted into and coupled to an inner peripheral surface thereof. The second bearing portion 172 may be formed of a bush bearing or a needle bearing.

Further, an oil accommodating space 156a extending in the axial direction from the end of the rotary shaft 130 is formed in the rear side inner portion of the second bearing portion 156, and the oil accommodating space 156a is positioned between a first oil supply guide flow path 157a and a second oil supply guide flow path 136, which will be described later. The first oil supply guide passage 157a may communicate with the discharge chamber S2, and the second oil supply guide passage 136 may communicate with bearing surfaces provided on the outer peripheral surfaces of the main bearing portion 132, the sub bearing portion 134, and the eccentric portion 133, respectively.

The first oil supply guide passage 157a may be formed in the fixed scroll 150 or in a rear housing 160 described later. For example, in the case where the first oil supply guide flow path 157a is formed in the fixed scroll 150, when the rear surface of the fixed scroll 150, that is, a surface facing the frame portion 112 among both side surfaces in the axial direction of the fixed scroll 150 is defined as the first surface 150a, and an opposite surface to the first surface 150a is defined as the second surface 150b, the oil supply protrusion 157 protruding in the direction toward the rear housing 160 is formed in the second surface 150b, and the first oil supply guide flow path 157a may be formed in the radial direction in the oil supply protrusion 157. A decompression member 191, which will be described later, may be inserted into the first oil supply guide passage 157a, and the decompression member 191 may be supported by a cover member 195 inserted into an inlet of the first oil supply guide passage 157 a.

One end of the first oil supply guide passage 157a may communicate with the outer peripheral surface of the fixed hard plate portion 151 through an oil supply through hole 195a described later, and the other end of the first oil supply guide passage 157a may communicate with the inner peripheral surface of the oil accommodating space 156 a.

Therefore, in the discharge chamber S2 of the rear housing 160, the high-pressure oil separated from the refrigerant rapidly moves to the oil accommodating space 156a along the first oil supply guide passage 157a due to the pressure difference, and the oil is rapidly supplied to the respective bearing surfaces through the second oil supply guide passage 136 and the respective oil supply holes 137a to 137c due to the pressure difference. The first oil supply guide flow path will be described again together with the impurity blocking portion.

Referring to fig. 3 again, one first oil supply guide flow path 136 and a plurality of

oil supply holes

137a, 137c may be formed at the rotation shaft 130. As described above, the first oil supply guide passage 136 is formed at the end of the rotary shaft 130, that is, at the rear end of the rotary shaft 130 accommodated in the oil accommodating space 156a, at a predetermined depth in the axial direction in the front end direction, and the plurality of

oil supply holes

137a, 137b, and 137c are formed at regular intervals in the axial direction in the middle of the first oil supply guide passage 136.

The plurality of

oil supply holes

137a, and 137c may be formed of a second oil supply hole 137b penetrating toward the outer circumferential surface of the sub bearing portion 134, a third oil supply hole 137c penetrating toward the outer circumferential surface of the eccentric portion 133, and a first oil supply hole 137a penetrating toward the outer circumferential surface of the main bearing portion 132.

Thus, the oil flowing from the oil accommodating space 156a into the first oil supply guide flow path 136 passes through the second oil supply hole 137b, the third oil supply hole 137c, and the first oil supply hole 137a in this order and is supplied to the respective bearing surfaces.

The rear housing 160 is coupled to a rear aspect of the fixed scroll 150. The front surface of the rear casing 160 forms a discharge chamber S2 together with the rear surface of the fixed scroll 150. The rear housing 160 has an exhaust port 161 formed therein, the exhaust port 161 communicating with the discharge chamber S2 to discharge the refrigerant discharged from the discharge chamber S2, and an oil separator (not shown) may be provided in the exhaust port 161.

On the other hand, the front end of the main casing 110, which is the end opposite to the rear casing 160 at both ends of the main casing 110 and constitutes the open end, may be covered with the inverter casing 210.

If reference is again made to fig. 1 to 3, the frequency converter housing 210 forms part of the frequency converter module 201, and a frequency converter chamber S4 is formed between the frequency converter housing 210 and the frequency converter cover 220.

The inverter compartment S4 accommodates inverter components 230 such as a substrate and inverter elements, the inverter case 210 and the inverter cover 220 are bolted, and the inverter cover 220 may be assembled after the inverter cover case 210 is first assembled to the main case 110, then to the inverter case 210,

the inverter housing 210 may be assembled to the main housing 110 after the inverter housing 210 and the inverter cover 220 are first assembled. The former and the latter can be distinguished according to the manner in which the inverter housing 210 is assembled to the main housing 110.

The unexplained reference numeral 114 denotes a first protrusion, 114a denotes a first flow path, 138 denotes a counter weight, 154 denotes a second protrusion, 154a denotes a second flow path, and 162 denotes a support protrusion.

The electric compressor according to the present embodiment described above operates as follows.

That is, when power is applied to the drive motor 120, the rotary shaft 130 rotates together with the rotor 122 and transmits the rotational force to the orbiting scroll 140, and the orbiting scroll 140 performs an orbiting motion by the oldham ring 180. Then, the compression chamber V continues to move toward the center side and the volume may decrease.

At this time, the refrigerant flows into the motor chamber S1 as a suction space through the suction port 101a, and the refrigerant flowing into the motor chamber S1 passes through a flow path formed by the outer peripheral surface of the stator 121 and the inner peripheral surface of the main casing 110 or a gap between the stator 121 and the rotor 122, and is sucked into the compression chamber V through a suction flow path Fg provided in the main casing 110 and the fixed scroll 150.

Then, the refrigerant is compressed by the orbiting scroll 140 and the fixed scroll 150, discharged to the discharge chamber S2 through the discharge port 155, and the oil is separated in the discharge chamber S2. The refrigerant from which the oil has been separated is discharged to the refrigeration cycle through the discharge port 161, while the oil is supplied in a spray form to the respective bearing surfaces through the first oil supply guide passage 157a, the oil accommodating space 156a, the second oil supply guide passage 136, and the oil supply holes 137a to 137c constituting the oil supply passage, and a part of the oil flows into the back pressure chamber S3, thereby forming a back pressure force that supports the orbiting scroll 140 toward the fixed scroll 150.

Then, the orbiting scroll 140 is supported in a direction toward the fixed scroll 150 by a back pressure of the back pressure chamber S3, thereby sealing the compression chamber V between the orbiting scroll 140 and the fixed scroll 150. At this time, a part of the oil in the back pressure chamber S3 flows into the compression chamber V through the back pressure hole 141a provided in the orbiting hard plate portion 141, and a part of the oil flows out to the motor chamber S1 through between the main bearing portion 132 and the first bearing portion 171, thereby repeating a series of processes of forming a flow pressure in the back pressure chamber S3 as described above.

In the electric compressor according to the present invention, as described above, the refrigerant oil in the spray form separated from the refrigerant in the discharge chamber flows into the oil accommodating space provided in the second bearing portion through the first oil supply guide passage, and the refrigerant oil is supplied to the bearing surface and the back pressure chamber through the second oil supply guide passage and the oil supply holes of the rotary shaft.

At this time, as the refrigerant oil becomes higher in pressure than the discharge pressure, the high-pressure refrigerant needs to be decompressed to an intermediate pressure and then supplied to the respective bearing surfaces and the back pressure chamber. If the refrigerant oil having a pressure higher than the discharge pressure is not reduced to an appropriate pressure, a part of the refrigerant oil flows into the compression chamber through the bearing surface, and the high-pressure refrigerant oil causes excessive compression in the compression chamber, which may reduce the compression efficiency. Also, a part of the refrigerant oil flows into the back pressure chamber, so that the pressure of the back pressure chamber excessively rises, and then the orbiting scroll excessively adheres to the fixed scroll, thereby possibly increasing a friction loss.

In contrast, in the present embodiment, a pressure reducing device may be provided which reduces the pressure of the refrigerant oil separated from the refrigerant in the discharge chamber to an appropriate pressure before the refrigerant oil is supplied to the bearing surface and the back pressure chamber. The pressure reducing device according to the present embodiment may be provided with an oil supply passage located upstream of the bearing surface and the back pressure chamber. This can prevent the refrigerant oil having a pressure higher than the discharge pressure from flowing into the bearing surface or the back pressure chamber.

Fig. 4 is a perspective view showing the decompression device according to fig. 3 in an exploded manner, and fig. 5 is a sectional view showing the decompression device according to fig. 4 in an assembled manner.

Referring to fig. 4 and 5, the pressure reducing device 190 according to the present embodiment includes a pressure reducing member 191, and the pressure reducing member 191 is inserted into the first oil supply guide flow path 157a that communicates between the discharge chamber S2 and the oil accommodating space 156 a. The decompression member 191 may be constituted by a pin member having a certain length and sectional area. However, since the decompression device 190 according to the present embodiment utilizes the cross-sectional area of the decompression passage 190a formed between the outer peripheral surface of the decompression member 191 and the inner peripheral surface of the first oil supply guide passage 157a and the length of the decompression passage 190a formed based on the length of the decompression member 191, the diameter and the length of the decompression member 191 can be appropriately adjusted in consideration of the pressure difference between the discharge chamber S2 and the first oil supply guide passage 157 a.

The first oil supply guide flow path 157a has both open ends, and has an oil supply inlet 1571 formed at a first end communicating with the discharge chamber S2 and an oil supply outlet 1572 formed at a second end communicating with the oil accommodating space 156 a. A decompression member housing 1573 into which the decompression member 191 is inserted is formed between the oil supply inlet 1571 and the oil supply outlet 1572.

As described above, in the decompression member housing 1573, the radial sectional area of the decompression member housing 1573 is formed larger than the radial sectional area of the decompression member 191 so that the decompression flow path 190a is formed between the outer peripheral surface of the decompression member 191 and the inner peripheral surface of the decompression member housing 1573. Thereby, the oil supply inlet 1571 and the decompression member accommodating portion 1573 and the oil supply outlet 1572 communicate with each other.

Here, the oil supply inlet 1571, the pressure reducing member accommodating portion 1573, and the oil supply outlet 1572 may be formed concentrically in the axial direction. However, if the oil supply inlet 1571, the decompression member accommodating portion 1573, and the oil supply outlet 1572 are formed concentrically, the oil supply inlet 1571 and the oil supply outlet 1572 may be blocked by the decompression member 191. In particular, since the discharge chamber S2 is relatively higher in pressure than the oil accommodating space 156a, the decompression member 191 is pushed toward the oil accommodating space 156a by the pressure of the discharge chamber S2 during the compressor operation. Therefore, the oil inlet 1571 is less likely to be blocked by the decompression member 191 if the length of the decompression member 191 is appropriately adjusted, but the oil outlet 1572 is likely to be blocked by the decompression member 191 pushed by the pressure of the discharge chamber S2.

In consideration of this, the oil supply outlet 1572 may be formed eccentrically with respect to the decompression member accommodating portion 1573 in this embodiment. Fig. 6 is a cross-sectional view taken along line "v-v" of fig. 5, which is a view for explaining the relative positions of the oil supply outlet and the pressure reducing member accommodating portion.

Referring to fig. 5 again, the axial center O' of the oil outlet 1572 is formed to move further toward the rear side, i.e., the rear case 160 side, with respect to the axial center O of the decompression member housing 1573. Thus, as shown in fig. 6, the axial center O' of the oil outlet 1572 can be eccentrically formed with a predetermined interval t from the axial center O of the pressure reducing member housing 1573.

The oil supply inlet 1571 is located at the lower end of the decompression member housing 1573 and is formed to be spaced apart from the bottom surface of the discharge chamber S2 by a predetermined distance. The decompression member 191 needs to be inserted through the oil supply inlet 1571, and thus the inner diameter D1 of the oil supply inlet 1571 is formed to be greater than or equal to the inner diameter D3 of the decompression member receiving portion 1573. Accordingly, since the inner diameter D1 of the oil inlet 1571 is formed to be larger than the diameter D4 of the decompression member 191, it is necessary to insert a separation preventing member into the oil inlet 1571 to block a part of the oil inlet 1571 in order to prevent the decompression member 191 from separating. As shown, the detachment prevention member may be pressed into the cover member 195 or bolted, and although not shown, may be formed of a pin member that blocks the lateral connection across the oil supply inlet 1571.

As shown in fig. 5, in the case where the separation preventing member is the cover member 195, at least one or more oil supply through holes 195a are formed so that the refrigerant oil flows from the discharge chamber S2 into the interior of the decompression member accommodating portion 1573. The oil supply through hole 195a may be formed at the center or at an edge position. However, the inner diameter D5 of the oil supply through hole 195a is formed smaller than the outer diameter D4 of the decompression member 191 thereof so that the decompression member 191 does not fall out.

Also, the inner diameter D1 of the oil supply inlet 1571 and the inner diameter D3 of the decompression member accommodating portion 1573 may be formed identically. However, in this case, it is necessary to suppress the cap member 195 from being pushed and pressed toward the decompression member accommodating portion 1573 by the pressure of the discharge chamber S2, such as by being pressed into the oil supply inlet 1571 or by being bolted to the cap member. Therefore, as shown in fig. 5, it is preferable that the inner diameter D1 of the oil supply inlet 1571 is formed larger than the inner diameter D3 of the decompression member accommodating section 1573, so that the oil supply inlet 1571 functions as a kind of cover member mounting groove.

As described above, when the axial center of the oil outlet 1572 is formed eccentrically with respect to the axial center of the pressure reducing member 191, even if the pressure reducing member 191 is placed in a free state inside the pressure reducing member housing 1573, the possibility that the oil outlet 1572 is blocked by the pressure reducing member 191 is significantly reduced.

Referring again to fig. 5, the axial length L1 of the pressure-reducing member-accommodating section 1573 may be formed larger than the axial length L2 of the pressure-reducing member 191. Thereby, the decompression member 191 can move up and down in a free state inside the decompression member housing 1573.

Fig. 7A is a schematic view showing the position of the decompression member 191 during operation in the decompression device according to fig. 5, and fig. 7B is a cross-sectional view taken along the line vi-vi in fig. 7A.

For example, when the compressor is stopped, the pressure in the discharge chamber S2 is equal to the pressure in the oil accommodating space 156a, and therefore the pressure reducing member 191 is lowered by its weight and placed on the cover member 195.

Thereafter, when the compressor is operated and the discharge chamber S2 is filled with the refrigerant oil, the pressure reducing member 191 is pushed up by the refrigerant oil, i.e., to the oil outlet 1572 side. At this time, the decompression member 191 may laterally block the oil outlet 1572, but the axial center O' of the oil outlet 1572 is formed eccentrically with respect to the axial center O of the decompression member accommodating portion 1573, thereby moving the refrigerant oil from the decompression flow path 190a to the oil outlet 1572 side. Then, as shown in fig. 7A and 7B, the refrigerant oil in the decompression member housing 1573 is concentrated to the oil supply outlet 1572 (right side in the figure) side centering on the decompression member 191 in the radial direction projection, and the decompression member 191 is pushed to the opposite side radial direction (left side in the figure), thereby securing the decompression flow path 190 a. Then, the decompression flow path 190a and the oil supply outlet 1572 are always in an open state, and the refrigerant oil in the discharge chamber S2 is smoothly moved to the oil accommodating space 156 a.

Thus, in the present embodiment, even if the decompression member 191 is placed in the decompression member housing 1573 in a freely movable state in the axial direction, the decompression member 191 can be prevented from blocking the decompression flow path 190a, that is, the oil supply outlet 1572. Then, the refrigerant oil passes through the pressure reducing device and is reduced in pressure, and can be smoothly supplied to the bearing surface, the compression chamber, and the back pressure chamber. Thereby, the refrigerant oil is rapidly and stably supplied to the corresponding portion, so that the reliability and the compression efficiency of the compressor can be improved.

In the present embodiment, the decompression passage 190a is formed by inserting the decompression member 191 into the first oil supply guide passage 15, so that the decompression passage 190a can be formed in a short and simple manner, and the length of the decompression member 191 and the cross-sectional area of the decompression passage 190a can be easily adjusted, thereby improving the decompression effect.

Further, by forming the decompression flow path 190a only in the fixed scroll 150, machining errors and assembly errors with respect to the decompression flow path 190a can be reduced, and thus, excessive reduction in the cross-sectional area of the decompression flow path 190a can be prevented, and pressure distribution can be made uniform while the degree of decompression can be easily adjusted.

Further, the inlet and the outlet of the oil supply guide passage are formed on both sides of the decompression member 191 in the longitudinal direction, respectively, whereby the effective length of the decompression passage 190a can be secured to a certain extent. Then, by maintaining the decompression effect constantly, the pressure in the back pressure chamber S3 is constantly formed, and the operation of the orbiting scroll is stabilized, thereby preventing leakage between the compression chambers and suppressing the compression loss.

In the present embodiment, the decompression passage 190a is formed by inserting the decompression member 191 into the first oil supply guide passage 157a, so that the orbiting scroll 140 or the fixed scroll 150 can be easily machined as compared with the decompression passage 190a formed by penetrating the hard plate portion of the orbiting scroll 140 or the fixed scroll 150 in the axial direction. This allows refrigerant oil to smoothly flow between the opposite scrolls, thereby improving reliability between the opposite scrolls.

Further, the decompression passage 190a is formed separately from the compression chamber V, and therefore, the refrigerant oil can be prevented from flowing backward into the compression chamber V through the decompression passage 190 a.

In the present embodiment, the pressure reducing flow path 190a is formed in front of the oil accommodating space 156a accommodating the rotary shaft 130, so that the axial load applied to the rotary shaft 130 in the axial direction can be reduced. This prevents the rotary shaft 130 from being exposed to the discharge pressure, thereby reducing the axial load applied to the rotary shaft 130, and thus, the life of the bearing that supports the rotary shaft 130 in the axial direction can be extended, and the friction loss can be reduced.

On the other hand, in the foregoing embodiment, the pressure-reducing member 191 may be placed in a free state in the pressure-reducing member housing 1573, or the pressure-reducing member 191 may be fixedly coupled to the pressure-reducing member housing 1573. Fig. 8 is a sectional view showing another embodiment of the pressure reducing member relating to fig. 3, and fig. 9 is a line sectional view "vii-vii" in fig. 8.

Referring to fig. 8 and 9, the axial length L1 of the pressure-reducing member-receiving portion 1573 may be formed the same as the axial length L2 of the pressure-reducing member 191. Accordingly, the upper end of the decompression member 191 abuts on the stepped surface 1573a formed between the second end of the decompression member accommodating portion 1573 and the oil outlet 1572, whereas the lower end of the decompression member 191 abuts on the upper surface of the cover member 195 coupled to the oil inlet 1571, thereby being supported.

The pressure-reducing member 191 may be formed in a circular end surface shape like the pressure-reducing member receiving portion 1573, and the diameter of the pressure-reducing member 191 may be formed smaller than the inner diameter of the pressure-reducing member receiving portion 1573. The decompression member 191 is eccentrically fixed to the decompression member receiving portion 1573. Thereby, the decompression flow path 190a can be formed between the outer peripheral surface of the decompression member 191 and the inner peripheral surface of the decompression member housing 1573.

The basic structure of the pressure reducing device according to the present embodiment and the operational effects thereof are similar to those of the foregoing embodiments. However, as in the present embodiment, in the case where the axial length L2 of the decompression member 191 and the axial length L1 of the decompression member accommodating portion 1573 are formed identically to fix both ends of the decompression member 191, it is possible to excessively block the oil supply outlet 1572 without fixing the decompression member 191 at a desired position by machining errors or assembly errors. Then, the sectional area of the oil supply outlet 1572 communicating with the decompression flow path 190a is not sufficiently secured, and the oil supply state may become poor.

In view of this, a decompression member support portion may also be formed at the second end of the decompression member accommodating portion 1573 as the upper end. The axial center of the pressure reducing member support portion is formed eccentrically with respect to the axial center of the oil supply outlet 1572. Fig. 10 is a sectional view showing still another embodiment of the decompression means relating to fig. 3, and fig. 11 is a sectional view taken along line viii-viii in fig. 10.

Referring to fig. 10 and 11, the axial center O ″ of the pressure reducing member support portion 1574 is eccentrically formed from the axial center O ' of the oil supply outlet 1572, and the axial center O of the pressure reducing member housing portion 1573 is eccentrically formed from the axial center O ' of the oil supply outlet 1572 in an eccentric direction to the axial center O ' of the pressure reducing member support portion 1574. That is, the axial center O ″ of the decompression member support portion 1574 may be located on a straight line on the opposite side of the axial center O' of the oil outlet 1572 with the axial center O of the decompression member housing portion 1573 as the center.

The basic structure of the pressure reducing device according to the present embodiment and the operational effects thereof are similar to those of the foregoing embodiments. However, if the decompression member supporting portion 1574 is further formed between the decompression member accommodating portion 1573 and the oil outlet 1572 as in the present embodiment, and a communication space is formed between the decompression member accommodating portion 1573 and the oil outlet 1572, even if the decompression member 191 is not fixed at a desired position due to a machining error or an assembly error, the decompression flow path 190a and the oil outlet 1572 can be prevented from being excessively blocked by the communication space, and thus it is possible to contribute to securing the decompression flow path 190 a.

On the other hand, in the decompression device of the electric compressor according to the present invention, the oil outlet and the decompression member housing may be provided in another embodiment as follows. That is, the clogging of the oil outlet is prevented by the oil outlet being formed eccentrically with respect to the decompression member accommodating portion in the foregoing embodiment, but it is desirable in this embodiment to prevent the clogging of the oil outlet 1572 even if the oil outlet 1572 is formed concentrically with respect to the decompression member accommodating portion 1573.

In this case, too, the oil supply outlet 1572 can be easily formed. However, as described above, in the case where the oil outlet 1572 is formed concentrically with the decompression member accommodating portion 1573, the decompression member 191 moves in a free state inside the decompression member accommodating portion 1573 and may block the oil outlet 1572. Therefore, in this case, it is important to be able to prevent the decompression member 191 from blocking the oil supply outlet 1572.

FIG. 12 is a sectional view showing another example of the pressure reducing device according to the present invention, and FIG. 13 is a sectional view taken along line IX-IX of FIG. 12.

Referring to fig. 12 and 13, the axial center O' of the oil outlet 1572 may be formed concentrically with the axial center O of the pressure reducing member housing 1573. In this case, the inner diameter D2 of the oil supply outlet 1572 may be formed smaller than the inner diameter D3 of the decompression member accommodating portion 1573.

The decompression member 191 may be inserted into and fixed to the inner circumferential surface of the decompression member housing 1573. However, in this case, the decompression passage 190a may be formed to penetrate axially through the center portion of the decompression member 191. The decompression flow path 190a may be formed concentrically with the oil supply outlet 1572, and the inner diameter of the decompression flow path 190a may be formed smaller than or equal to the inner diameter of the oil supply outlet 1572.

Further, if the workability with respect to the decompression passage 190a is taken into consideration, it is advantageous to form the length of the decompression member 191 short, but if the decompression effect is taken into consideration, it is advantageous to form the effective length of the decompression passage as long as possible. Therefore, it is advantageous to form the length L2 of the pressure-reducing member 191 to be as long as possible as the length L1 of the pressure-reducing member-accommodating portion 1573. However, as described above, the decompression flow path 190a may be formed of a material that is easily processed, that is, a material having a hardness lower than that of the fixed scroll 150, such as plastic, in consideration of the workability of the decompression flow path.

As described above, in the case where the decompression member 191 has the decompression flow path 190a formed at the center thereof and is fixed to the decompression member accommodating portion 1573, the decompression member accommodating portion 1573 and the oil outlet 1572 may be formed concentrically, and in this case, the decompression member accommodating portion 1573 or the oil outlet 1572 can be easily processed.

Further, the decompression member 191 is inserted into and fixed to the decompression member housing 1573, so that a cover member supporting the decompression member can be eliminated, the number of parts and the number of assembly processes can be reduced, and the manufacturing cost can be reduced. Of course, although not shown, the decompression member 191 may be inserted into the decompression member housing 1573 and may be supported by another cover member or fixing member.

On the other hand, FIG. 14 is a sectional view showing another example of the pressure reducing means for fixing the pressure reducing member in the pressure reducing apparatus according to the present invention, and FIG. 15 is a sectional view taken along line "X-X" of FIG. 14.

Referring to fig. 14 and 15, the pressure reducing member 191 may be formed at one end thereof with a support protrusion 191a expanded in a radial direction, and a support groove portion (or oil supply inlet) 1573b may be formed at a first end of the pressure reducing member receiving portion 1573 in a radial expansion to support the support protrusion 191a in an axial direction.

The support protrusion 191a is formed concentrically with the axial center of the pressure reducing member 191, and the support groove part 1573b is formed concentrically with the axial center of the pressure reducing member accommodating part 1573 so as to correspond to the support protrusion 191 a. Thereby, the communication flow path 1573c may be formed at one side in the radial direction of the support protrusion 191a such that the inner circumferential surface of the support groove portion (or the oil supply inlet) 1573 is spaced from each other to communicate with the decompression flow path 190 a.

As shown in fig. 15, the support protrusion 191a may be formed in a circular shape, but may be formed in a rectangular shape in some cases. The support groove part 1573b may be formed in the same shape as the support protrusion 191 a. However, a communication flow path 1573c is formed on one radial side of the support groove 1573b, so that the discharge chamber S2 can communicate with the reduced pressure flow path 190 a.

Also, the length L2 of the decompression member 191 may be formed shorter than the length L1 of the decompression member accommodating portion 1573. Thereby, the oil outlet 1572 and an end portion of the decompression member 191 facing the oil outlet 1572 are spaced from each other, so that the communication space 190b may be formed to communicate the decompression flow path 190a and the oil outlet 1572.

However, although not shown, the length L2 of the decompression member 191 may be formed in the same manner as the length L1 of the decompression member accommodating portion 1573, or a communication groove may be formed in a stepped manner or inclined manner at the end of the decompression member L2 facing the oil supply outlet 1572. In this case, the communication groove may form a communication space.

The basic structure of the pressure reducing device according to the present embodiment and the operational effects thereof are similar to those of the foregoing embodiments. However, as shown in fig. 14, when the pressure reducing member 191 is formed with the support protrusion 191a to restrict the movement in the axial direction, the communication space 190b in which the end portion of the pressure reducing member 191 and the oil supply outlet 1572 are spaced apart from each other by a certain interval can be secured. Thus, even if the decompression member accommodating portion 157a and the oil outlet 1572 are concentrically formed, the communication space 190b can prevent the blockage between the decompression flow path 190a and the oil outlet 1572 in advance.

On the other hand, the pressure reducing apparatus 190 according to the present invention may be configured such that the pressure reducing member housing 1573 and the oil outlet 1572 are formed concentrically, and the pressure reducing member 191 may be moved in a free state inside the pressure reducing member housing 1573. Fig. 16 is a sectional view showing an example in which a decompression member is in a free state in the decompression apparatus according to the present invention, and fig. 17 is a sectional view taken along the line XI-XI in fig. 16.

Referring to fig. 16 and 17, the axial center O of the decompression member housing 1573 and the axial center O' of the oil outlet 1572 are formed concentrically, the length L2 of the decompression member 191 is formed shorter than the length L1 of the decompression member housing 1573, and the outer diameter D4 of the decompression member 191 is formed smaller than the inner diameter D3 of the decompression member housing 1573. Thereby, a decompression flow path 190a is formed between the outer peripheral surface of the decompression member 191 and the inner peripheral surface of the decompression member housing 1573.

However, in this case, the pressure reducing member 191 is disposed in a free state inside the pressure reducing member housing 1573, and thus the oil supply outlet 1572 can be blocked when the pressure reducing member 191 is pressed to the second end side of the pressure reducing member housing 1573. Therefore, in the present embodiment, a communication space portion 191b may be formed at an end portion of the decompression member 191 facing the oil outlet 1572.

As shown in the drawing, the communication space portion 191b may be formed as an inclined surface inclined in a direction toward the fuel outlet 1572, and may be formed as a stepped surface, although not shown.

The basic structure of the pressure reducing device according to the present embodiment and the operational effects thereof are similar to those of the foregoing embodiments. However, as in the present embodiment, when the communication space portion 191b is formed at the end portion of the pressure reducing member 191, in the case where the pressure reducing member accommodating portion 1573 and the fuel outlet 1572 are concentrically formed, even if the pressure reducing member 191 is placed in the pressure reducing member accommodating portion 1573 in a free state, it is possible to prevent the pressure reducing member 191 from blocking the fuel outlet 1572 due to the communication space portion 191b in advance.

On the other hand, in the electric compressor according to the present invention, another embodiment of the oil supply passage is as follows.

That is, in the foregoing embodiment, in the case where the oil supply inlet 1571 constituting the inlet of the first oil supply guide flow path 157a is formed with the same inner diameter as the decompression member accommodating portion 1573 or is inserted into the cover member 195, a single or a plurality of oil supply through holes 195a may be formed in the cover member 195 thereof. However, in the above-described embodiment, the inner diameter of the oil supply inlet 1571, that is, the radial sectional area of the oil supply inlet 1571 may be formed larger than the radial sectional area of the decompression flow path 190 a.

Then, the impurities mixed into the refrigerant oil from the discharge chamber S2 may flow into the decompression flow path 190a through the oil supply inlet 1571 to block the decompression flow path 190a, or may flow into the bearing surface or the compression chamber through the decompression flow path 190a to cause wear in the bearing surface or the compression chamber.

Thus, in the present embodiment, an impurity blocking member may be provided at the oil supply inlet 1571. The impurity blocking member may be provided with a simple filter such as a mesh. However, when the mesh is provided, resistance to the flow path of the refrigerant oil increases, and the amount of suction of the refrigerant oil may decrease. Fig. 18 is a sectional view showing an impurity blocking member provided at an oil supply inlet in the electric compressor according to the present invention.

Referring to fig. 18, the impurity blocking member 196 according to the present embodiment may be formed by a cover member provided at the oil supply inlet 1571. A plurality of oil supply through holes 196a are formed in the impurity blocking member 196, and the plurality of oil supply through holes 196a are formed in the same direction, i.e., in parallel in the axial direction. The cross-sectional area of each oil supply through hole 196a is formed to be smaller than or equal to the cross-sectional area of the decompression flow path 190 a.

On the other hand, as in the other embodiments described above, for example, the pressure reducing member 191 is inserted into and fixed to the pressure reducing member housing part 1573, and thus in the embodiment in which no other cover member is provided, the impurity blocking member as described in fig. 18 may be provided. However, the impurity blocking member 196 in this case may be formed of a thin plate material and screwed or bolted in a state of covering and abutting on the first end of the decompression member accommodating section 1573. In this case, a plurality of oil supply through holes 196a may be formed in the impurity blocking member 196 to penetrate in the same direction.

When the impurity blocking member 196 is provided as described above, the impurities are prevented from flowing into the decompression flow path 190a, and the decompression flow path 190a is prevented from being blocked or the impurities flow into the bearing surface or the compression chamber to be abraded, whereby the reliability can be improved.

On the other hand, in the electric compressor according to the present invention, there are other examples of the installation position of the decompression device as follows. That is, the decompression device is provided to the fixed scroll in the foregoing embodiment, but the decompression device is provided to the rear housing in the present embodiment. Fig. 19 is a cross-sectional view showing an example in which the pressure reducing device according to the present embodiment is provided in the rear case.

Referring to fig. 19, a front bearing part 162 of the rear housing 160 is formed to be protruded toward the fixed scroll 150, and an oil protrusion 163 is formed to be long in a radial direction at a lower end of the bearing part 162.

An oil accommodating space 162a is formed inside the bearing portion 162, a first oil supply guide flow path 163a is formed in the oil supply protrusion 163, and the pressure reducing member 191 as described above can be inserted into the first oil supply guide flow path 163 a.

The configuration of the first oil supply guide flow path 163a according to the present embodiment, which is composed of the oil supply inlet 1631, the oil supply outlet 1632, and the pressure reducing member accommodating portion 1633, and the configuration of the pressure reducing member 191 inserted into the first oil supply guide flow path 163a, are the same as those of the above-described embodiments. Therefore, a detailed description thereof will be omitted. However, as in the present embodiment, when the oil supply passage and the pressure reducing device are provided in the rear housing, the machining of the fixed scroll can be simplified. This simplifies the machining of the fixed scroll, which requires relatively higher precision than the rear housing, and reduces machining errors of the fixed scroll.

Claims

1. An electric compressor, comprising:

a housing provided with a motor chamber;

a drive motor provided in the motor chamber of the housing, and having a stator and a rotor;

a rotating shaft coupled to the rotor;

a first scroll provided on one side of the drive motor, the rotation shaft penetrating in an axial direction and eccentrically coupled to the drive motor, the first scroll performing a revolving motion by the rotation shaft;

a second scroll coupled to the first scroll to form a compression chamber together with the first scroll, the second scroll being rotatably inserted through a rotation shaft of the first scroll and coupled thereto;

a rear housing provided on one side of the second scroll and forming a discharge chamber together with the second scroll;

a bearing portion provided at the second scroll or the rear housing, and radially supporting the rotary shaft;

an oil supply guide passage provided in the second scroll or the rear housing and communicating the discharge chamber with the inside of the bearing portion; and

and a decompression member inserted into the oil supply guide passage and configured to decompress the pressure of the fluid passing through the oil supply guide passage.

2. The electric compressor according to claim 1,

an oil supply protrusion is formed to extend from the bearing portion in a radial direction,

the oil supply guide passage is formed to penetrate the oil supply protrusion in the radial direction.

3. The electric compressor according to claim 2,

both ends of the oil supply guide flow path are open, a first end communicated with the spitting chamber forms an oil supply inlet, a second end communicated with the inside of the bearing part forms an oil supply outlet,

a decompression member accommodating portion into which the decompression member is inserted is formed between the oil supply inlet and the oil supply outlet,

a radial sectional area of the decompression member housing is formed larger than a radial sectional area of the decompression member such that a decompression flow path is formed between an outer circumferential surface of the decompression member and an inner circumferential surface of the decompression member housing,

the oil supply inlet, the decompression member accommodating portion, and the oil supply outlet are formed in a continuous communication manner.

4. The electric compressor according to claim 3,

the oil supply outlet is formed eccentrically with respect to the decompression member accommodating portion,

the axial length of the decompression member accommodating portion is formed to be greater than the axial length of the decompression member.

5. The electric compressor according to claim 3,

the axial length of the decompression member accommodating portion is formed to be the same as the axial length of the decompression member,

a decompression member support portion supporting the decompression member in an axial direction is formed in a stepped manner between the oil supply outlet and the first end of the decompression member accommodation portion,

the axial center of the pressure reducing member support portion is formed eccentrically with respect to the axial center of the oil supply outlet.

6. The electric compressor according to claim 3,

the oil supply outlet and the oil supply inlet are formed on the same line along the axial direction,

the decompression member is inserted into and fixedly coupled to the decompression member receiving portion,

the pressure reducing member has a pressure reducing passage formed at a central portion thereof so as to axially penetrate therethrough, and the pressure reducing passage communicates with the oil supply outlet.

7. The electric compressor according to claim 6,

8. The electric compressor according to claim 3,

the decompression member is formed with a support protrusion having one end thereof expanded in a radial direction, a support groove portion is formed at an end of the decompression member accommodating portion on the oil supply inlet side so as to support the support protrusion in an axial direction,

the oil supply outlet and an end of the decompression member facing the oil supply outlet are spaced apart from each other to form a communication space to communicate the decompression flow path with the oil supply outlet.

9. The electric compressor according to claim 8,

a communication space portion is formed toward the oil supply outlet at an end portion of the pressure reducing member facing the oil supply outlet.

10. The electric compressor according to any one of claims 1 to 9,

an impurity blocking member is further provided at the oil supply guide flow path to block impurities, the impurity blocking member having a plurality of oil supply through holes,

the impurity blocking member is formed so as to be positioned on the discharge chamber side with the decompression member as a center.