JP7469405B2 - Electric motors and compressors - Google Patents

Description

The present invention relates to an electric motor for a compressor and a compressor in which a compression mechanism is driven by an electric motor, and in particular to an improved technology for a passage provided in the electric motor through which a mixed gas containing a cooling medium and lubricating oil flows.

2. Description of the Related Art A compressor disclosed in Patent Document 1 (JP 2007-285266 A) is known as a compressor provided in air conditioners (such as home air conditioners and vehicle air conditioners), refrigerators, and the like.
The compressor disclosed in Patent Document 1 includes a sealed container, a compression mechanism, and an electric motor that drives the compression mechanism. The compression mechanism and the electric motor are housed in the sealed container. The electric motor is disposed vertically above the compression mechanism (vertical arrangement). In addition, an oil reservoir is provided vertically below the compression mechanism to store lubricating oil to be supplied to sliding parts of the compression mechanism.
The electric motor has a stator formed by a stator core, and a rotor formed by a rotor core. The stator core is provided with a plurality of passages that extend in the vertical direction and are open on both sides in the vertical direction.
In the sealed container, a mixed gas containing a cooling medium compressed by the compression mechanism and fine lubricating oil flows vertically upward through a passage provided in the stator core, and is discharged from a discharge port provided vertically upward in the sealed container.
If the lubricating oil stored in the oil sump runs short, poor lubrication of the compression mechanism occurs. On the other hand, it is difficult to replenish the lubricating oil in the sealed container. For this reason, the lubricating oil contained in the mixed gas is configured to be returned to the oil sump.
The lubricating oil contained in the mixed gas discharged from the discharge pipe is separated by the accumulator and returned to the oil sump, but the amount of lubricating oil recovered by the accumulator is small.
For this reason, the lubricating oil contained in the mixed gas in the sealed container is configured to be returned to the oil reservoir via a passage provided in the stator core. In other words, the cross-sectional area of the passage is set so that the lubricating oil contained in the mixed gas flows vertically downward through the passage under its own weight against the viscosity of the lubricating oil.

JP 2007-285266 A

In recent years, the use of natural refrigerants with a small global warming potential (GWP) as a cooling medium for a compressor has been considered. In particular, carbon dioxide, which is neither toxic nor flammable, has attracted attention among natural refrigerants. When carbon dioxide is used as a refrigerant, the temperature and pressure inside the sealed container become higher than when a fluorocarbon-based cooling medium is used. For this reason, it is necessary to use a lubricating oil with a high viscosity as a lubricating oil for lubricating the sliding parts of the compression mechanism.
In order to return the highly viscous lubricating oil to the oil reservoir through the passage, the cross-sectional area of the passage needs to be increased. In addition, in Patent Document 1, hydraulic diameter is used as an index of the cross-sectional area of the passage. The hydraulic diameter indicates the diameter of a circular cross-section passage equivalent to a non-circular cross-section passage, and is expressed as [4 x (cross-sectional area of the passage) / circumference of the passage].
However, in the compressor disclosed in Patent Document 1, increasing the cross-sectional area of the passages changes the characteristics of the motor. For example, in the case where the stator core is made of a plurality of laminated plate-shaped electromagnetic steel sheets, increasing the cross-sectional area of the passages of the stator core increases the magnetic flux density of the electromagnetic steel sheets. And, when the magnetic flux density of the magnetic flux flowing through the electromagnetic steel sheets increases, the iron loss of the electromagnetic steel sheets increases.
In particular, in the electric motor disclosed in Patent Document 1, lubricating oil may flow in the axial direction on a circumferential portion of the passage forming surface that forms the passage. In this case, an oil film is formed on a circumferential portion of the passage forming surface so as to protrude from the passage forming surface to the inside of the passage. When such an oil film is formed, the effective cross-sectional area of the passage is reduced. In other words, the hydraulic diameter is reduced. Considering the oil film that is formed on a portion of the passage forming surface and that protrudes locally to the inside of the passage, it is necessary to further increase the cross-sectional area of the passage.
For this reason, there is a demand for the development of technology that can return highly viscous lubricating oil to the oil pool through a passage without increasing the cross-sectional area of the passage.
The present invention was devised in consideration of these points, and aims to provide a technology that can return lubricating oil to an oil reservoir while reducing the cross-sectional area of the passage through which a mixed gas containing a cooling medium and lubricating oil flows.

The first invention relates to an electric motor, in particular, to an electric motor for a compressor.
The electric motor of the first aspect of the present invention includes a stator and a rotor. The stator has a stator core, and the rotor has a rotor core.
The rotor core is arranged to be rotatable about the axis.
The stator core is formed in a cylindrical shape extending in the axial direction of the axis. The stator core has an inner peripheral surface, an outer peripheral surface, and a stator core inner space defined by the inner peripheral surface. The rotor core is disposed in the stator core inner space.
At least one of the stator core and the rotor core is provided with at least one passage that extends in the axial direction and is open on both sides in the axial direction.
In the present invention, the rotor core is arranged so that its axis extends in the vertical direction (including the "substantially vertical direction"). The stator core is also arranged so that its axis extends in the vertical direction (including the "substantially vertical direction").
At least one of the passages has at least one groove having an opening extending along the circumferential direction of the passage forming surface, the groove (groove opening) being provided so as to extend along the entire circumference or a partial region of the circumferential direction of the passage forming surface.
A groove having an opening in the passage forming surface is formed by a first groove forming surface and a second groove forming surface. The first groove forming surface is formed so as to extend in a horizontal direction (including a "substantially horizontal direction") from the passage forming surface. The second groove forming surface is disposed vertically above the first groove forming surface. The second groove forming surface is formed so that the distance between the first groove forming surface and the second groove forming surface in the vertical direction becomes shorter with increasing distance from the passage forming surface in the horizontal direction (including a "substantially horizontal direction").
The passage forming surface is formed with grooves extending along the circumferential direction of the passage forming surface, so that the lubricating oil flowing from the vertically upward direction to the vertically downward direction along a portion of the passage forming surface enters the grooves and flows along the extension direction of the grooves (the circumferential direction of the passage forming surface) . This makes it possible to prevent the local formation of an oil film that protrudes from the passage forming surface to the inside of the passage in a portion of the passage forming surface along the circumferential direction. In other words, it is possible to reduce the maximum thickness of the oil film formed on the passage forming surface. And, by reducing the maximum thickness of the oil film, it is possible to increase the effective cross-sectional area of the passage.
In the electric motor of the present invention, the cross-sectional area of the passage through which the mixed gas containing the cooling medium and lubricating oil flows can be reduced while the lubricating oil can be returned to the oil reservoir.
As the passage for flowing the mixed gas containing the cooling medium and the lubricating oil, various passages can be used.
In another embodiment of the first aspect of the present invention, the compressor includes a sealed container having an inner peripheral surface and an inner space defined by the inner peripheral surface and configured to accommodate a stator core and a rotor core.
The stator core has a first stator core outer peripheral surface and a second stator core outer peripheral surface, and is housed in the sealed container inner space with the first stator core outer peripheral surface in contact with the sealed container inner peripheral surface and the second stator core outer peripheral surface separated from the sealed container inner peripheral surface.
In the electric motor of this embodiment, at least one first stator passage is provided in the stator core. The first stator passage is defined by a first stator passage forming surface including an outer circumferential surface of the second stator core and an inner circumferential surface of the sealed container.
At least one of the first stator passages has at least one groove having an opening extending along the circumferential direction of the first stator passage forming surface, the groove being provided in a first stator passage forming surface that forms the first stator passage.
In this embodiment as well, the cross-sectional area of the passage through which the mixed gas containing the cooling medium and the lubricating oil flows can be reduced, while the lubricating oil can be returned to the oil pool.
In a different embodiment of the first aspect of the present invention, at least one rotor passage is provided in the rotor core. The rotor passage is defined by a rotor passage forming surface including a rotor passage inner wall surface formed in the rotor core.
At least one of the rotor passages has at least one groove having an opening extending entirely around the circumferential direction of the rotor passage forming surface, the groove being provided in a rotor passage forming surface that defines the rotor passage.
In this embodiment as well, the cross-sectional area of the passage through which the mixed gas containing the cooling medium and the lubricating oil flows can be reduced, while the lubricating oil can be returned to the oil pool.
In a different embodiment of the first aspect of the present invention, the stator core is provided with at least one second stator passage. The second stator passage is defined by a second stator passage forming surface including a second stator passage inner wall surface formed in the stator core.
At least one of the second stator passages has at least one groove having an opening extending completely around the circumferential direction of the second stator passage forming surface, the second stator passage forming surface having the second stator passage formed therein.
In this embodiment as well, the cross-sectional area of the passage through which the mixed gas containing the cooling medium and the lubricating oil flows can be reduced, while the lubricating oil can be returned to the oil pool.
In a different embodiment of the first aspect of the present invention, the stator core and the rotor core are made of a plurality of laminated plate-shaped electromagnetic steel sheets.
The plurality of electromagnetic steel sheets have a first surface on a first side in the sheet thickness direction and a second surface on a second side in the sheet thickness direction. The plurality of electromagnetic steel sheets are stacked such that the first surface and the second surface face each other and the second surface is disposed vertically above the first surface.
The plurality of electromagnetic steel plates are cut in the plate thickness direction in the regions corresponding to the passages. As a result, a passage forming surface portion is formed at a location corresponding to the passage forming surface. The passage forming surface portion has a groove forming surface portion at a location on the second surface side along the plate thickness direction. The groove forming surface portion is formed such that the distance along the plate thickness direction between the groove forming surface portion and the second surface becomes shorter with increasing distance from the passage forming surface portion along the extension direction of the second surface.
The passage forming surface is formed by the passage forming surface portions of the stacked electromagnetic steel sheets, and the first groove forming surface is formed by the first surface of the electromagnetic steel sheet that is disposed vertically lower among two vertically adjacent electromagnetic steel sheets, and the groove forming surface portion of the electromagnetic steel sheet that is disposed vertically upper forms the second groove forming surface.
In this embodiment, the lubricating oil can be returned to the oil reservoir via a passage through which a mixed gas containing a cooling medium and lubricating oil flows, while suppressing an increase in iron loss in the electromagnetic steel sheets that make up the stator core or rotor core.
In another embodiment of the first aspect of the present invention, the thickness of the electromagnetic steel sheet is set within a range of 0.25 mm to 0.35 mm. The length of the groove forming surface portion along the thickness direction is set within a range of 0.03 mm to 0.08 mm. The length of the groove forming surface portion from the passage forming surface portion along the extension direction of the second surface is set within a range of 0.05 mm to 0.15 mm.
In this embodiment, the lubricating oil that flows vertically from above to below along the passage forming surface can flow within the groove along the extension direction of the groove while suppressing an increase in iron loss of the electromagnetic steel sheet.
The second invention relates to a compressor.
The compressor of the present invention includes a sealed container, a compression mechanism that compresses a refrigerant, and an electric motor that drives the compression mechanism.
The sealed container has an inner circumferential surface and an inner space defined by the inner circumferential surface of the sealed container. The compression mechanism and the electric motor are accommodated in the inner space of the sealed container such that the electric motor is disposed vertically above the compression mechanism.
As the electric motor, any one of the electric motors described above is used.
The compressor of the second invention has the same effects as any of the electric motors described above.

By using the electric motor and compressor of the present invention, it is possible to reduce the cross-sectional area of the passage through which the mixed gas containing the cooling medium and lubricating oil flows while returning the lubricating oil to the oil reservoir.

FIG. 2 is a cross-sectional view of a compressor according to an embodiment. FIG. 2 is an enlarged view of a main part of FIG. 1 . 3 is a cross-sectional view taken along the line III-III of FIG. 2. FIG. 2 is a diagram showing a schematic configuration of a rotor passage of an electric motor according to the present invention; 1 is a diagram comparing a rotor passage of an electric motor according to an embodiment with a rotor passage of a conventional electric motor; FIG. 2 is a cross-sectional view of a rotor passage of an electric motor according to one embodiment. FIG. 7 is a perspective view of FIG. FIG. 2 is a diagram showing a schematic configuration of a first stator passage of the electric motor of the present invention; FIG. 2 is a cross-sectional view of a first stator passage of an electric motor according to one embodiment. FIG. 10 is a perspective view of FIG. FIG. 4 is a diagram showing a schematic configuration of a second stator passage of the electric motor of the present invention. FIG. 4 is a cross-sectional view of a second stator passage of the electric motor of one embodiment. FIG. 13 is a perspective view of FIG.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
In the following description, "axis" refers to the rotation center line P of the rotor core (rotor) when the rotor core (rotor) is rotatably supported relative to the stator core (stator). "Axial direction" refers to the extension direction of the rotation center line (axis) P (the direction indicated by the arrows X-Y in the figure). Furthermore, "circumferential direction" refers to the circumferential direction centered on the rotation center line (axis) P when viewed from one axial side or the other axial side (see FIG. 3) when the rotor is rotatably supported relative to the stator. Furthermore, "radial direction" refers to the direction passing through the rotation center line (axis) P when viewed from one axial side or the other axial side when the rotor is rotatably supported relative to the stator.
Additionally, the terms "above" or "upper side", unless otherwise specified, refer to above (vertically upward) or upper side (vertically upward) in the vertical direction (the direction indicated by arrow Y in the figure), and the terms "below" or "lower side", unless otherwise specified, refer to below (vertically downward) or lower side (vertically lower) in the vertical direction (the direction indicated by arrow X in the figure).

An embodiment of a compressor of the present invention will be described with reference to Fig. 1. Fig. 1 is a cross-sectional view of a compressor 10 according to the embodiment.
The compressor 10 of the present embodiment is configured as a rotary-type hermetic compressor in which a rotary-type compression mechanism and an electric motor are disposed in a hermetic container.
The compressor 10 is composed of a sealed container 20, a compression mechanism 30, an accumulator 40, an electric motor 100, and the like.
The sealed container 20 has an inner peripheral surface 21. The inner peripheral surface 21 defines an inner space of the sealed container.
The compression mechanism 30 and the electric motor 100 are housed in the space inside the sealed container. In this embodiment, the electric motor 100 is disposed above the compression mechanism 30.
In the sealed container 20, an intake port 22 is provided below the electric motor 100, and an exhaust port 23 is provided above the electric motor 100. In addition, an oil reservoir 36 for storing lubricating oil to be supplied to the bearings 34 and 35 of the rotating shaft 430, the sliding parts of the compression mechanism 30, and the like is provided at the bottom of the sealed container 20 (below the compression mechanism 30).
The sealed container 20 corresponds to the "sealed container" of the present invention, and the inner peripheral surface 21 of the sealed container corresponds to the "inner peripheral surface of the sealed container" of the present invention.

The compression mechanism 30 compresses a cooling medium (hereinafter simply referred to as "refrigerant") that transfers thermal energy. In this embodiment, a natural refrigerant with a small global warming potential (GWP), in particular carbon dioxide, which is neither toxic nor flammable, is used as the refrigerant. Of course, various refrigerants other than carbon dioxide can be used. When carbon dioxide is used as the refrigerant, the temperature and pressure inside the sealed container 20 become higher than when a fluorocarbon-based refrigerant is used. For this reason, a lubricating oil with a high viscosity is used as the lubricating oil.

The compression mechanism 30 is composed of a cylinder 31, an eccentric rotor 32 that is rotated by a rotary shaft 430, and a compression chamber 33. The rotary shaft 430 is rotatably supported by bearings 34 and 35.
When the eccentric rotor 32 of the compression mechanism 30 rotates due to the rotation of the rotary shaft 430 , the refrigerant sucked from the suction port 22 is compressed in the compression chamber 33 .
The refrigerant compressed by the compression mechanism 30 is mixed with fine lubricating oil particles. Then, the mixed gas containing the compressed refrigerant and the fine lubricating oil particles flows through a passage (refrigerant passage) provided in the electric motor 100, and is discharged from the discharge port 23. The passage (refrigerant passage) provided in the electric motor 100 will be described later.
The accumulator 40 separates the refrigerant and the lubricating oil contained in the mixed gas discharged from the discharge port 23. The refrigerant separated from the mixed gas in the accumulator 40 is returned to the compression mechanism 30 via the suction pipe 41 and the suction port 22. The lubricating oil separated from the mixed gas in the accumulator 40 is returned to the oil reservoir 36.
By the rotation of the rotating shaft 430, the lubricating oil stored in the oil reservoir 36 is supplied to the bearings 34 and 35, the sliding parts of the compression mechanism 30, etc. The lubricating oil that has lubricated the bearings 34 and 35 and the sliding parts of the compression mechanism 30 is returned to the oil reservoir 36.
In addition, when the mixed gas that flows above the electric motor 100 through the passages provided in the electric motor 100 comes into contact with the inner peripheral surface of the sealed container 20 and is cooled, the lubricating oil contained in the mixed gas is separated and falls downward. Then, the lubricating oil flows downward through the passages provided in the electric motor 100 and is returned to the oil reservoir 36.

Next, the configuration of the electric motor 100 will be described with reference to Figures 1 to 3. Figure 2 is an enlarged view of a main portion of Figure 1. Figure 3 is a cross-sectional view of Figure 2 as viewed from the direction of the arrow III-III. Note that the electric motor 100 represents one embodiment of the electric motor of the present invention.
In one embodiment, the electric motor 100 is configured as an interior permanent magnet motor.
The electric motor 100 is composed of a sealed container 20, a stator 200, a rotor 300, and the like.

The stator 200 includes a stator core 210 and a stator winding 230 .
The stator core 210 is formed of a laminated body of a plurality of plate-shaped electromagnetic steel sheets 500. The stator core 210 is formed in a cylindrical shape and arranged to extend in the axial direction. The stator core 210 has a stator core end face 210A on a first axial side (upper side) and a stator core end face 210B on a second axial side (lower side).
As shown in FIG. 3 when the compressor 10 is viewed from one side in the axial direction, the stator core 210 has a yoke 214 and a plurality of teeth 215 .
The yoke 214 extends in the circumferential direction. The teeth 215 are arranged at positions spaced apart along the circumferential direction and extend radially inward from the yoke 214. The teeth 215 have teeth tip surfaces 216 extending in the circumferential direction at their tips on the radially inner side (the side of the rotation center line P). The teeth tip surfaces 216 form a stator core inner space 220 in which the rotor core 310 (rotor 300) is arranged.
A slot 217 is formed by circumferentially adjacent teeth 215. A stator winding 230 is inserted into the slot 217.
3 shows a stator core 210 having nine slots 217 (9 slots). Of course, the number of slots in the stator core 210 is not limited to nine.
In this embodiment, the stator core 210 is provided with a first stator passage 240 and a second stator passage 250 (described in detail below).

The rotor 300 includes a rotor core 310 and a rotating shaft 430 .
The rotor core 310 is formed in a cylindrical shape by stacking a plurality of plate-shaped electromagnetic steel sheets 600. The rotor core 310 has a rotor core outer peripheral surface 311, a rotor core inner peripheral surface 312, and a rotor core inner space 320 formed by the rotor core inner peripheral surface 312.
The rotating shaft 430 is inserted into the rotor core inner space 320 by press fitting or the like.
The rotor core 310 is disposed in the stator core inner space 220 so as to be rotatable around a rotation center line P. The rotor core 310 has a rotor core end face 310A on a first axial side (upper side) and a rotor core end face 310B on a second axial side (lower side).
In addition, end plates 410 are arranged on both sides in the axial direction with a plurality of electromagnetic steel sheets 600 stacked. Then, rivet pins 420 are inserted into rivet pin insertion holes 330 formed in each electromagnetic steel sheet 600 and end plate 410, thereby forming a laminate with each electromagnetic steel sheet 600 aligned. The rivet pin insertion holes 330 of each electromagnetic steel sheet 600 are formed by rivet pin insertion hole inner wall surfaces 313 formed in each electromagnetic steel sheet 600. The number and arrangement locations of the rivet pin insertion holes 330 (rivet pin insertion hole inner wall surfaces 313) are not limited to the number and arrangement locations shown in FIG. 3.
In addition, the rotor core 310 has main poles [A] to [F] and auxiliary poles [AB] to [FA] arranged alternately along the circumferential direction. The main poles [A] to [F] are formed with magnet insertion hole inner wall surfaces 314 that form magnet insertion holes 340. A permanent magnet 350 is inserted into the magnet insertion holes 340. The main poles [A] to [F] are defined by the d-axis that connects the rotation center line P and the circumferential centers of the main poles [A] to [F], and the auxiliary poles [AB] to [FA] are defined by the q-axis that connects the rotation center line P and the circumferential centers of the auxiliary poles [AB] to [FA].
3 shows a rotor core 310 having six poles. Of course, the number of poles of the rotor core 310 is not limited to six.
In this embodiment, the rotor core 310 is provided with a rotor passage 360 (described in detail below).

Next, we will explain the first stator passage 240 and the second stator passage 250 provided in the stator core 210 of the electric motor 100, and the rotor passage 360 provided in the rotor core 310.

First, the rotor passage 360 will be described.
The electric motor 100 of this embodiment is disposed so that the rotation center line P extends in the vertical direction (including the "substantially vertical direction"). Therefore, the "axial direction" and the "vertical direction" indicate the same direction.
The rotor passage 360 is defined by the rotor passage forming surface, extends in the axial direction, and is open on both axial sides, that is, the rotor passage 360 is open to the rotor core end faces 310A and 310B.
The rotor passage forming surface includes a rotor passage inner wall surface 315 formed in the rotor core 310. In this embodiment, the rotor passage 360 (rotor passage inner wall surface 315) has a cross section formed in a circular shape (including a "substantially circular shape") centered on the center line Q.
In addition, in this embodiment, as shown in FIG. 3, the rotor passages 360 are formed in multiple locations radially inward from the permanent magnets 350 (the inner wall surface 314 of the magnet insertion hole) on the d axis of the main poles [A] to [F].
Of course, the shape, number and location of the rotor passages 360 are not limited to those shown in FIG.

A schematic diagram of the rotor passage 360 is shown in FIG.
As shown in FIG. 4, a rotor passage inner wall surface 315 (rotor passage forming surface) that forms the rotor passage 360 has a plurality of grooves 360A formed therein.
The groove 360A has a first groove forming surface 315a, a second groove forming surface 315b, and an opening 315c. The opening 315c is open to the rotor passage inner wall surface 315 along the circumferential direction of the rotor passage inner wall surface 315 all around.
The first groove forming surface 315a extends in a direction perpendicular to the axial direction (including a direction substantially perpendicular to the axial direction). In the present embodiment, the first groove forming surface 315a extends in a horizontal direction (including a direction substantially horizontal to the axial direction).
The second groove forming surface 315b is disposed above the first groove forming surface 315a. The second groove forming surface 315b is formed such that the distance between the first groove forming surface 315a and the second groove forming surface 315b in the axial direction (the distance in the vertical direction in this embodiment) becomes shorter as the distance from the rotor passage inner wall surface 315 increases along the extension direction of the first groove forming surface 315a. The second groove forming surface 315b can be formed in various shapes such as a flat shape or a curved shape.
It is sufficient that at least one groove 360A is provided on rotor passage inner wall surface 315 .

Rotor passage 360 corresponds to the "rotor passage" of the present invention. Rotor passage inner wall surface 315 corresponds to the "rotor passage forming surface that forms the rotor passage." Alternatively, rotor passage 360 defined by rotor passage inner wall surface 315 corresponds to the "rotor passage defined by the rotor passage forming surface including the rotor passage inner wall surface" of the present invention.
Groove 360A formed by first groove forming surface 315a, second groove forming surface 315b and opening 315c corresponds to "a groove having an opening extending entirely around the circumferential direction of the passage forming surface (rotor passage forming surface)" of this invention.

The difference between the rotor passage 360 of this embodiment and the conventional rotor passage 360 will be described with reference to FIG.
FIG. 5(a) shows a conventional rotor passage 360, and FIG. 5(b) shows the rotor passage 360 of this embodiment.
When the lubricating oil contained in the mixed gas flows in the axial direction (vertical direction in this embodiment) along the rotor passage inner wall surface 315, it may flow through some points along the circumferential direction of the rotor passage inner wall surface 315.
In a conventional rotor passage 360, as shown in FIG. 5( a), an oil film is formed at some locations along the circumferential direction of the rotor passage inner wall surface 315, protruding from the rotor passage inner wall surface 315 toward the center line Q.
When an oil film is formed locally on the rotor passage inner wall surface 315, the shape of the effective passage (a portion excluding the oil film) in the rotor passage 360 changes. Also, the cross-sectional area of the effective passage in the rotor passage 360 decreases.
For this reason, in conventional electric motors, it is necessary to set the cross-sectional area of the rotor passage 360, for example the inner diameter D of the rotor passage 360, taking into consideration the local formation of an oil film within the rotor passage 360.
On the other hand, in the rotor passage 360 of this embodiment shown in FIG. 5( b ), a groove 360</b>A is formed in the rotor passage inner wall surface 315 , the groove 360</b>A extending entirely around the circumferential direction of the rotor passage inner wall surface 315 .
In the electric motor of this embodiment, when the lubricating oil contained in the mixed gas flows in the axial direction (vertical direction in this embodiment) at some points along the circumferential direction of the rotor passage inner wall surface 315, the lubricating oil enters the groove 360A and flows along the groove 360A. By the lubricating oil flowing in the groove 360A along the extension direction of the groove 360A, the oil film formed on the rotor passage inner wall surface 315 is made uniform along the circumferential direction of the rotor passage inner wall surface 315. In other words, it is possible to prevent the local formation of an oil film protruding toward the center line Q on the rotor passage inner wall surface 315, and the shape of the effective passage is maintained in a substantially circular shape.
Therefore, it is not necessary to increase the cross-sectional area of the rotor passage 360, for example, the inner diameter D of the rotor passage 360. In other words, the inner diameter D of the rotor passage 360 can be set smaller than the inner diameter of a conventional rotor passage 360.

In this embodiment, the rotor core 310 is formed of a laminated body in which a plurality of plate-shaped electromagnetic steel sheets 600 are stacked.
A method for forming rotor passages 360 in rotor core 310 formed of a plurality of laminated electromagnetic steel plates 600 will be described with reference to Fig. 6 and Fig. 7. Fig. 6 is an enlarged cross-sectional view of rotor passage 360 of rotor core 310, and Fig. 7 is a perspective view of Fig. 6.
The electromagnetic steel sheet 600 has a first surface 601 on a first side in the sheet thickness direction, and a second surface 602 on a second side in the sheet thickness direction.
The electromagnetic steel sheet 600 is cut in the plate thickness direction in a region corresponding to the rotor passage 360, and a rotor passage inner wall surface portion 615 extending in the plate thickness direction is formed at a location corresponding to the rotor passage inner wall surface 315. Furthermore, a rotor passage portion 660 is formed in the region corresponding to the rotor passage 360.
Further, a groove forming surface portion 615b is formed on the rotor passage inner wall surface portion 615 at a location on the second surface 602 side. The groove forming surface portion 615b is formed such that the distance in the plate thickness direction between the groove forming surface portion 615b and the second surface 602 becomes shorter as it moves away from the rotor passage inner wall surface portion 615 along the extension direction of the second surface 602.
As a method for forming the groove forming surface portion 615b, an appropriate method can be used. For example, a method can be used in which the groove forming surface portion 615b is formed together with the rotor passage inner wall surface portion 615 when cutting the region of the electromagnetic steel sheet 600 corresponding to the rotor passage 360.
A first groove forming surface portion 615a is formed by a portion of the first surface 601 of the electromagnetic steel sheet 600 on the rotor passage inner wall surface portion 615 side.

When stacking the multiple electromagnetic steel sheets 600 , they are stacked so that the second surfaces 602 are positioned above and facing the first surfaces 601 .
Then, with the plurality of electromagnetic steel sheets 600 stacked, the crimping pins 420 are inserted into the crimping pin insertion holes 330 of each of the electromagnetic steel sheets 600 to align the electromagnetic steel sheets 600 .
In this state, the rotor passage inner wall surface 315 is formed by the rotor passage inner wall surface portions 615 of each electromagnetic steel sheet 600. In other words, the rotor passage 360 is formed by the rotor passage portions 660 of each electromagnetic steel sheet 600.
Of the two vertically adjacent electromagnetic steel sheets 600, a portion 615a on the rotor passage inner wall surface portion 615 side of a first surface 601 of the electromagnetic steel sheet 600 that is located lower defines a first groove forming surface 315a of the groove 360A. Also, of the two axially adjacent electromagnetic steel sheets 600, a groove forming surface portion 615b of the electromagnetic steel sheet 600 that is located upper defines a second groove forming surface 315b of the groove 360A.
Of the two electromagnetic steel sheets adjacent in the vertical direction, a groove portion 660A is formed by a first surface 601 of the electromagnetic steel sheet 600 disposed below and a groove forming surface portion 615b of the electromagnetic steel sheet 600 disposed above. A groove 360A having an opening 615c extending all around along the circumferential direction of the rotor passage inner wall surface 315 is formed by groove portion 660A formed between the electromagnetic steel sheet 600 disposed above and the electromagnetic steel sheet 600 disposed below.

The electromagnetic steel sheet 600 corresponds to the "electromagnetic steel sheet forming the rotor core" of the present invention. A first surface 601 and a second surface 602 of the electromagnetic steel sheet 600 correspond to the "first surface of the electromagnetic steel sheet forming the rotor core" and the "second surface of the electromagnetic steel sheet forming the rotor core" of the present invention, respectively.
The rotor passage inner wall surface portion 615 corresponds to the "passage forming surface portion" or the "rotor passage forming surface portion" of the present invention. The groove forming surface portion 615b corresponds to the "groove forming surface portion" of the present invention.
A groove portion 660A formed by the first surface 601 (first groove forming surface portion 615a), the groove forming surface portion 615b, and the opening 615c corresponds to the "groove portion" of the present invention.

The sheet thickness H of the electromagnetic steel sheet 600 is set within the range of 0.25 mm to 0.35 mm ([0.25 mm≦H≦0.35 mm]).
Furthermore, if the length T of the groove forming surface portion 615b (second groove forming surface 315b) along the plate thickness direction is smaller than 0.03 mm, the lubricating oil will not easily enter the groove portion 660A (groove 360A).
If the length T exceeds 0.08 mm, the magnetic flux density of the electromagnetic steel sheet 600 increases. If the magnetic flux density of the electromagnetic steel sheet 600 increases, the core loss of the electromagnetic steel sheet 600 increases.
Therefore, the length T of the groove forming surface portion 615b (second groove forming surface 315b) along the plate thickness direction is set within the range of 0.03 mm to 0.08 mm ([0.03 mm≦T≦0.08 mm]).
Furthermore, if the length W of the groove forming surface portion 615b (second groove forming surface 315b) along the extending direction of the second surface 602 is smaller than 0.05 mm, the lubricating oil does not easily flow inside the groove portion 660A (groove 360A).
If the length W exceeds 0.15 mm, the magnetic flux density of the electromagnetic steel sheet 600 increases. If the magnetic flux density of the electromagnetic steel sheet 600 increases, the core loss of the electromagnetic steel sheet 600 increases.
Therefore, the length W of the groove forming surface portion 615b (second groove forming surface 315b) along the extension direction of the second surface 602 is set within the range of 0.05 mm to 0.15 mm ([0.05 mm≦W≦0.15 mm]).
The plate thickness H of the electromagnetic steel plate, and the length T and length W of the groove forming surface portion are the same for the first stator passage 240 and the second stator passage 250.

Next, the first stator passage 240 will be described.
In this embodiment, as shown in FIG. 3, the inner peripheral surface 21 of the sealed container 20 is formed in a circular shape with the rotation center line P as the center point.
Further, the stator core outer peripheral surface 211 of the stator core 210 is composed of a first stator core outer peripheral surface 212 and a second stator core outer peripheral surface 213. In this embodiment, the first stator core outer peripheral surface 212 is formed in an arc shape with the rotation center line P as the center point. The second stator core outer peripheral surface 213 is formed in a linear shape obtained by cutting out a circular shape extending from the first stator core outer peripheral surface 212. In other words, the second stator core outer peripheral surface 213 passes through the rotation center line P and extends linearly in a direction intersecting a line extending in the radial direction.
Then, the stator core 210 is fitted into the space inside the sealed container 20. For example, the stator core 210 is press-fitted or shrink-fitted. At this time, the stator core 210 is housed in the space inside the sealed container with the first stator core outer peripheral surface 212 in contact with the sealed container inner peripheral surface 21 and the second stator core outer peripheral surface 213 separated from the sealed container inner peripheral surface 21.

A schematic configuration of the first stator passage 240 is shown in FIG.
3 and 8, the first stator passage 240 is defined by the second stator core outer peripheral surface 213 and the sealed container inner peripheral surface 21. That is, the first stator passage 240 is defined by a passage forming surface (first stator passage forming surface) including the second stator core outer peripheral surface 213 and the sealed container inner peripheral surface 21.
The first stator passage 240 extends in the axial direction and is open on both axial sides thereof, that is, the first stator passage 240 is open to the stator core end faces 210A and 210B.
In this embodiment, the first stator passage 240 has a cross section formed in a notched shape obtained by cutting out a circle.

A groove 240A extending in the circumferential direction of the second stator core outer peripheral surface 213 is formed in the second stator core outer peripheral surface 213 (first stator passage forming surface) which forms the first stator passage 240 .
The groove 240A has a first groove forming surface 213a, a second groove forming surface 213b, and an opening 213c. The opening 213c opens in the second stator core outer peripheral surface 213 along the circumferential direction of the second stator core outer peripheral surface 213.
Groove 360A of rotor passage 360 is formed in rotor passage inner wall surface 315 that forms rotor passage 360, and groove 240A of first stator passage 240 is formed in second stator core outer peripheral surface 213 that forms first stator passage 240, except that groove 360A of rotor passage 360 is formed in rotor passage inner wall surface 315 that forms rotor passage 360, and groove 240A of first stator passage 240 is formed in second stator core outer peripheral surface 213 that forms first stator passage 240.
In this embodiment, as shown in FIG. 3 , a plurality of first stator passages 240 are formed on the outer periphery of the stator core 210 .
Of course, the shape, number and location of the first stator passages 240 are not limited to those shown in FIG.
It is sufficient that at least one groove 240A is provided on the outer circumferential side of the stator core 210 .

The first stator passage 240 corresponds to the "first stator passage" of the present invention. The second stator core outer peripheral surface 213 and the sealed container inner peripheral surface 21 constitute a "first stator passage forming surface forming the first stator passage" of the present invention. Alternatively, the first stator passage 240 formed by the second stator core outer peripheral surface 213 and the sealed container inner peripheral surface 21 corresponds to the "first stator passage formed by the first stator passage forming surface including the second stator core outer peripheral surface and the sealed container inner peripheral surface" of the present invention.
A groove 240A constituted by the first groove forming surface 213a, the second groove forming surface 213b and the opening 213c corresponds to "a groove having an opening extending along the circumferential direction of the passage forming surface (first stator passage forming surface)" of this invention.

In this embodiment, the stator core 210 is formed of a laminated body in which a plurality of plate-shaped electromagnetic steel sheets 500 are stacked.
A method for forming the first stator passage 240 in the stator core 210 formed of a plurality of laminated electromagnetic steel sheets 500 is shown in Figures 9 and 10. Figure 9 is an enlarged cross-sectional view of the first stator passage 240 of the stator core 210, and Figure 10 is a perspective view of Figure 9.
The electromagnetic steel sheet 500 has a first surface 501 on a first side in the sheet thickness direction, and a second surface 502 on a second side in the sheet thickness direction. Furthermore, the electromagnetic steel sheet outer peripheral surface 511 of the electromagnetic steel sheet 500 has a first electromagnetic steel sheet outer peripheral surface 512 and a second electromagnetic steel sheet outer peripheral surface 513. Note that if the first stator passage 240 is not provided in the stator core 210, the second electromagnetic steel sheet outer peripheral surface 513 can be omitted.
The electromagnetic steel sheet 500 is cut in the thickness direction in an area corresponding to the first stator passage 240, and a second electromagnetic steel sheet outer surface 513 extending in the thickness direction is formed at a location corresponding to the second stator core outer surface 213.
Further, a groove forming surface portion 513b is formed on the second surface 502 side of the second electromagnetic steel sheet outer peripheral surface 513. The groove forming surface portion 513b is formed such that the distance in the sheet thickness direction between the groove forming surface portion 513b and the second surface 502 becomes shorter with increasing distance from the second electromagnetic steel sheet outer peripheral surface 513 along the extension direction of the second surface 502.
As a method for forming the groove forming surface portion 513b, a method similar to the method for forming the groove forming surface portion 615b in the electromagnetic steel sheet 600 described above can be used.
A first groove forming surface portion 513a is formed by a portion of the first surface 501 of the electromagnetic steel sheet 500 on the side of the outer circumferential surface 513 of the second electromagnetic steel sheet.
The electromagnetic steel sheets 500 are laminated using a method similar to the method for laminating the electromagnetic steel sheets 600 described above.
When stacked, the second stator core outer peripheral surface 213 is formed by the second magnetic steel sheet outer peripheral surface 513 of each magnetic steel sheet 500 .
Of the two vertically adjacent electromagnetic steel sheets 500, the first groove forming surface portion 513a on the second electromagnetic steel sheet outer surface 513 side of the first surface 501 of the electromagnetic steel sheet 500 that is located lower forms the first groove forming surface 213a of the groove 240A.
Of the two electromagnetic steel sheets 500 adjacent in the vertical direction, the second groove forming surface portion 513b of the electromagnetic steel sheet 500 that is disposed above forms the second groove forming surface 213b of the groove 240A.
Of the two electromagnetic steel sheets adjacent in the vertical direction, groove portion 540A is formed by first surface 501 of electromagnetic steel sheet 500 arranged below and second groove forming surface portion 513b of electromagnetic steel sheet 500 arranged above. Groove portion 540A formed between electromagnetic steel sheet 500 arranged above and electromagnetic steel sheet 500 arranged below forms groove 240A having opening 213c extending along the circumferential direction of second stator core outer peripheral surface 213.
The first stator passage 240 is formed by accommodating the stator core 210 in the space inside the sealed container.

Electromagnetic steel sheet 500 corresponds to the "electromagnetic steel sheet forming the stator core" of the present invention. First surface 501 and second surface 502 of electromagnetic steel sheet 500 correspond to the "first surface of the electromagnetic steel sheet forming the stator core" of the present invention and the "second surface of the electromagnetic steel sheet forming the stator core" of the present invention, respectively.
The second electromagnetic steel sheet outer peripheral surface 513 corresponds to the "passage forming surface portion" or the "first stator passage forming surface portion" of the present invention. The groove forming surface portion 513b corresponds to the "groove forming surface portion" of the present invention.
A groove portion 540A formed by the first surface 501 (first groove forming surface portion 513a), the groove forming surface portion 513b and the opening 513c corresponds to the "groove portion" of the present invention.

Next, the second stator passage 250 will be described.
The second stator passage 250 is defined by a second stator passage forming surface, extends in the axial direction, and is open on both axial sides thereof, i.e., the second stator passage 250 is open to the stator core end faces 210A and 210B.
The second stator passage forming surface includes a second stator passage inner wall surface 218 formed in the stator core 210. In this embodiment, the second stator passage 250 (second stator passage inner wall surface 218) has a cross section formed in a circular shape (including a "substantially circular shape") centered on the center line R.
In this embodiment, as shown in FIG. 3 , a plurality of second stator passages 250 are formed at locations corresponding to the yoke 214 .
Of course, the shape, number and location of the second stator passages 250 are not limited to those shown in FIG.

A schematic configuration of the second stator passage 250 is shown in FIG.
As shown in FIG. 11, a plurality of grooves 250A are formed in a second stator passage inner wall surface 218 (second stator passage forming surface) that defines the second stator passage 250.
The groove 250A has a first groove forming surface 218a, a second groove forming surface 218b, and an opening 218c. The opening 218c is open to the second stator passage inner wall surface 218 along the circumferential direction of the second stator passage inner wall surface 218 all around.
The second stator passage 250 has a similar configuration to the rotor passage 360, and therefore a description thereof will be omitted.

The second stator passage 250 corresponds to the "second stator passage" of the present invention. The second stator passage inner wall surface 218 corresponds to the "second stator passage forming surface that forms the second stator passage". Alternatively, the second stator passage 250 defined by the second stator passage inner wall surface 218 corresponds to the "second stator passage defined by a passage forming surface including the second stator passage inner wall surface" of the present invention.
Groove 250A constituted by first groove forming surface 218a, second groove forming surface 218b and opening 218c corresponds to the "groove having an opening extending around the entire circumference of the passage forming surface (second stator passage forming surface) in the circumferential direction" of the present invention.

In this embodiment, the stator core 210 is formed of a laminated body in which a plurality of plate-shaped electromagnetic steel sheets 500 are stacked.
12 and 13 show a method for forming the second stator passage 250 in the stator core 210 formed of a plurality of laminated electromagnetic steel plates 500. Fig. 12 is an enlarged cross-sectional view of a portion of the stator core 210 corresponding to the second stator passage 250, and Fig. 13 is a perspective view of Fig. 12.
The second stator passage 250 formed by a plurality of stacked electromagnetic steel plates 500 has a similar configuration to the rotor passage 360 formed by a plurality of stacked electromagnetic steel plates 600, and therefore a description thereof will be omitted.

The second stator passage inner wall surface portion 518 corresponds to the "passage forming surface portion" or the "second stator passage forming surface portion" of the present invention. The groove forming surface portion 518b corresponds to the "groove forming surface portion" of the present invention.
A groove portion 550A formed by the first surface 501 (first groove forming surface portion 518a), the groove forming surface portion 518b, and the opening 518c corresponds to the "groove portion" of the present invention.

The present invention can also be configured as follows.
(Aspect 1)
The rotor has a rotor core rotatable about an axis,
The stator core is formed in a cylindrical shape extending in the axial direction of the axis, and has a stator core inner peripheral surface, a stator core outer peripheral surface, and a stator core inner space formed by the stator core inner peripheral surface,
The rotor core is disposed in the stator core inner space,
At least one of the stator core and the rotor core is provided with at least one passage extending in the axial direction and opening on both sides in the axial direction,
An electric motor characterized in that at least one of the passages has at least one groove having an opening extending along the circumferential direction of the passage forming surface, the groove being provided in a passage forming surface that defines the passage.
(Aspect 2)
2. The electric motor of aspect 1,
a sealed container having an inner circumferential surface of the sealed container and an inner space of the sealed container formed by the inner circumferential surface of the sealed container and accommodating the stator core and the rotor core;
The stator core outer peripheral surface has a first stator core outer peripheral surface and a second stator core outer peripheral surface,
the stator core is accommodated in the sealed container inner space in a state in which the first stator core outer peripheral surface is in contact with the sealed container inner peripheral surface and the second stator core outer peripheral surface is separated from the sealed container inner peripheral surface,
The stator core is provided with at least one first stator passage formed by a first stator passage forming surface including the second stator core outer peripheral surface and the sealed container inner peripheral surface,
an electric motor, characterized in that at least one of the first stator passages has at least one groove having an opening extending along a circumferential direction of the first stator passage forming surface, the groove being provided in a first stator passage forming surface that forms the first stator passage.
(Aspect 3)
The electric motor of aspect 1 or 2,
The rotor core is provided with at least one rotor passage formed by a rotor passage forming surface including a rotor passage inner wall surface,
an electric motor, characterized in that at least one of the rotor passages has at least one groove having an opening extending completely around the circumferential direction of the rotor passage forming surface, the rotor passage forming surface having the rotor passage formed therein.
(Aspect 4)
The electric motor according to any one of aspects 1 to 3,
The stator core is provided with at least one second stator passage formed by a second stator passage forming surface including a second stator passage inner wall surface,
an electric motor, characterized in that at least one of the second stator passages has at least one groove having an opening extending entirely around the circumferential direction of the second stator passage forming surface, the second stator passage forming surface having the groove.
(Aspect 5)
The rotor includes a rotor core that is rotatable around an axis of the rotor, and a sealed container.
the sealed container has an inner circumferential surface of the sealed container, and an inner space of the sealed container formed by the inner circumferential surface of the sealed container and accommodating the stator core and the rotor core,
The stator core is formed in a cylindrical shape extending in the axial direction of the axis, and has a stator core inner peripheral surface, a stator core outer peripheral surface, and a stator core inner space formed by the stator core inner peripheral surface,
The rotor core is disposed in the stator core inner space,
At least one of the stator core and the rotor core is provided with at least one passage formed by a passage forming surface, extending in the axial direction, and having both sides open in the axial direction,
As the passage, at least one of a first stator passage formed by a first stator passage forming surface including the outer peripheral surface of the stator core and the inner peripheral surface of the sealed container, a second stator passage formed by a second stator passage forming surface including a second stator passage inner wall surface formed in the stator core, and a rotor passage formed by a rotor passage forming surface including a rotor passage inner wall surface formed in the rotor core is provided,
an electric motor, characterized in that at least one of the first stator passage, the second stator passage, and the rotor passage has at least one groove having an opening extending along a circumferential direction of the passage forming surface provided in a passage forming surface that forms the passage.
(Aspect 6)
The electric motor according to any one of aspects 1 to 5,
The rotor core is disposed so that the axis extends in a vertical direction,
The groove having an opening in the passage forming surface is formed by a first groove forming surface and a second groove forming surface,
The first groove forming surface is formed to extend horizontally from the passage forming surface,
The second groove forming surface is positioned vertically above the first groove forming surface, and the distance between the first groove forming surface and the second groove forming surface along the vertical direction is formed so as to become shorter as the distance from the passage forming surface increases along the horizontal direction.
(Aspect 7)
7. The electric motor of claim 6,
The stator core and the rotor core are formed of a plurality of laminated plate-shaped electromagnetic steel sheets,
The plurality of electromagnetic steel sheets have a first surface on a first side in a sheet thickness direction and a second surface on a second side in a sheet thickness direction, and are stacked such that the first surface and the second surface face each other and are positioned vertically above the first surface;
the plurality of electromagnetic steel plates are cut in the plate thickness direction in regions corresponding to the passages, so that a passage forming surface portion is formed at a location corresponding to the passage forming surface, the passage forming surface portion has a groove forming surface portion at a location on the second surface side along the plate thickness direction, and the groove forming surface portion is formed such that a distance along the plate thickness direction between the groove forming surface portion and the second surface becomes shorter the farther away from the passage forming surface portion along the extension direction of the second surface,
The passage forming surface is formed by the passage forming surface portions of the plurality of electromagnetic steel plates,
an electric motor characterized in that, of two vertically adjacent electromagnetic steel plates, the first groove forming surface is formed by the first surface of the electromagnetic steel plate that is arranged vertically downward, and the second groove forming surface is formed by the groove forming surface portion of the electromagnetic steel plate that is arranged vertically upward.
(Aspect 8)
8. The electric motor of aspect 7,
An electric motor characterized in that the thickness of the electromagnetic steel plate is set within a range of 0.25 mm to 0.35 mm, the length of the groove forming surface portion along the plate thickness direction is set within a range of 0.03 mm to 0.08 mm, and the length of the groove forming surface portion from the passage forming surface portion along the extension direction of the second surface is set within a range of 0.05 mm to 0.15 mm.
(Aspect 9)
The compressor includes a sealed container, a compression mechanism that compresses a refrigerant, and an electric motor that drives the compression mechanism.
The sealed container has an inner peripheral surface and an inner space formed by the inner peripheral surface of the sealed container,
The compression mechanism and the electric motor are housed in the sealed container inner space such that the electric motor is disposed vertically above the compression mechanism,
A compressor, characterized in that the electric motor according to any one of aspects 1 to 8 is used as the electric motor.

The present invention is not limited to the configurations described in the embodiments, and various modifications, additions, and deletions are possible.
In the embodiment, a first stator passage formed by a first stator passage forming surface including the outer peripheral surface of the second stator core and the inner peripheral surface of the sealed container, a second stator passage formed by a second stator passage forming surface including the second stator passage inner wall surface, and a rotor passage formed by a rotor passage forming surface including the rotor passage inner wall surface are provided, but it is sufficient if at least one of the first stator passage, the second stator passage, and the rotor passage is provided.
The cross-sectional shape, number, arrangement position, etc. of the first stator passages can be changed as appropriate.
The cross-sectional shape, number, arrangement position, etc. of the second stator passages can be changed as appropriate.
The cross-sectional shape, number and arrangement of the rotor passages can be changed as appropriate.
In the embodiment, the fixed core and the rotating core are formed of a laminated body in which a plurality of plate-shaped electromagnetic steel sheets are laminated together, but the present invention is not limited to this.
The cross-sectional shape, number, arrangement, etc. of the grooves formed in the passage forming surface can be changed as appropriate.
In the embodiment, the grooves of the first stator passage are formed on a portion (the outer peripheral surface of the second stator core) along the circumferential direction of the first stator passage forming surface (the outer peripheral surface of the second stator core, the inner peripheral surface of the sealed container) that forms the first stator passage, but they may also be formed on the entire circumferential direction of the first stator passage forming surface (the outer peripheral surface of the second stator core and the inner peripheral surface of the sealed container).
In the embodiment, an embedded permanent magnet motor has been described that has a rotor in which a magnet insertion hole is formed and a permanent magnet is inserted into the magnet insertion hole. However, the motor of the present invention is not limited to an embedded permanent magnet motor and can be configured as various types of motors that have a rotor and a stator.
In the embodiment, the case where the motor is used in a compressor (a motor for a compressor) has been described, but the motor of the present invention can also be used for purposes other than a compressor.
Each of the configurations described in the embodiments can be used alone, or multiple appropriately selected configurations can be used in combination.

10 Compressor 20 Sealed container 21 Sealed container inner circumferential surface 22 Suction port 23 Discharge port 30 Compression mechanism section 31 Cylinder 32 Eccentric rotor 33 Compression chamber 34, 35 Bearing section 36 Oil reservoir 40 Accumulator 41 Suction pipe 100 Motor 200 Stator 210 Stator core 210A, 210B Stator core end surface 211 Stator core outer circumferential surface 212 First stator core outer circumferential surface 213 Second stator core outer circumferential surface 214 Yoke 215 Teeth 216 Teeth tip surface 217 Slot 218 Stator passage inner wall surface (second stator passage inner wall surface)
220 Stator core inner space 230 Stator winding 240 Stator passage (first stator passage)
240A Groove 250 Stator passage (second stator passage)
250A Groove 300 Rotor 310 Rotor core 310A, 310B Stator core end face 311 Rotor core outer peripheral surface 312 Rotor core inner peripheral surface 313 Crimping pin insertion hole inner wall surface 314 Magnet insertion hole inner wall surface 315 Rotor passage inner wall surface 320 Rotor core inner space 330 Crimping pin insertion hole 340 Magnet insertion hole 350 Permanent magnet 360 Rotor passage 360A Groove 410 End plate 420 Crimping pin 430 Rotating shaft 500, 600 Electromagnetic steel plate 501, 601 First surface 502, 602 Second surface 511 Electromagnetic steel plate outer peripheral surface 512 First electromagnetic steel plate outer peripheral surface 513 Second electromagnetic steel plate outer peripheral surface 513a, 518a, 615a First groove forming surface portion 513b, 518b, 615b Second groove forming surface portion 513c, 518c, 615c Opening 518 Stator passage inner wall surface portion (second stator passage inner wall surface portion)
540A, 550A, 660A Groove portion 615 Rotor passage inner wall surface portion 660 Rotor passage portion

Claims (7)

The rotor has a rotor core rotatable about an axis,
The stator core is formed in a cylindrical shape extending in the axial direction of the axis, and has a stator core inner peripheral surface, a stator core outer peripheral surface, and a stator core inner space formed by the stator core inner peripheral surface,
The rotor core is disposed in the stator core inner space,
At least one of the stator core and the rotor core is provided with at least one passage extending in the axial direction and opening on both sides in the axial direction,
The rotor core is disposed so that the axis extends in a vertical direction,
At least one of the passages is provided with at least one groove having an opening extending along a circumferential direction of the passage forming surface, in a passage forming surface that forms the passage ,
The groove having an opening in the passage forming surface is formed by a first groove forming surface and a second groove forming surface,
The first groove forming surface is formed to extend horizontally from the passage forming surface,
The second groove forming surface is positioned vertically above the first groove forming surface, and the distance between the first groove forming surface and the second groove forming surface along the vertical direction is formed so as to become shorter as the distance from the passage forming surface increases along the horizontal direction . 2. The electric motor according to claim 1,
a sealed container having an inner circumferential surface of the sealed container and an inner space of the sealed container formed by the inner circumferential surface of the sealed container and accommodating the stator core and the rotor core;
The stator core outer peripheral surface has a first stator core outer peripheral surface and a second stator core outer peripheral surface,
the stator core is accommodated in the sealed container inner space in a state in which the first stator core outer peripheral surface is in contact with the sealed container inner peripheral surface and the second stator core outer peripheral surface is separated from the sealed container inner peripheral surface,
The stator core is provided with at least one first stator passage formed by a first stator passage forming surface including the second stator core outer peripheral surface and the sealed container inner peripheral surface,
an electric motor, characterized in that at least one of the first stator passages has at least one groove having an opening extending along a circumferential direction of the first stator passage forming surface, the groove being provided in a first stator passage forming surface that forms the first stator passage. 2. The electric motor according to claim 1,
The rotor core is provided with at least one rotor passage formed by a rotor passage forming surface including a rotor passage inner wall surface,
an electric motor, characterized in that at least one of the rotor passages has at least one groove having an opening extending completely around the circumferential direction of the rotor passage forming surface, the rotor passage forming surface having the rotor passage formed therein. 2. The electric motor according to claim 1,
The stator core is provided with at least one second stator passage formed by a second stator passage forming surface including a second stator passage inner wall surface,
an electric motor, characterized in that at least one of the second stator passages has at least one groove having an opening extending entirely around the circumferential direction of the second stator passage forming surface, the second stator passage forming surface having the groove. The electric motor according to any one of claims 1 to 4 ,
The stator core and the rotor core are formed of a plurality of laminated plate-shaped electromagnetic steel sheets,
The plurality of electromagnetic steel sheets have a first surface on a first side in a sheet thickness direction and a second surface on a second side in a sheet thickness direction, and are stacked such that the first surface and the second surface face each other and are positioned vertically above the first surface;
the plurality of electromagnetic steel plates are cut in the plate thickness direction in regions corresponding to the passages, so that a passage forming surface portion is formed at a location corresponding to the passage forming surface, the passage forming surface portion has a groove forming surface portion at a location on the second surface side along the plate thickness direction, and the groove forming surface portion is formed such that a distance along the plate thickness direction between the groove forming surface portion and the second surface becomes shorter the farther away from the passage forming surface portion along the extension direction of the second surface,
The passage forming surface is formed by the passage forming surface portions of the plurality of electromagnetic steel plates,
an electric motor characterized in that, of two vertically adjacent electromagnetic steel plates, the first groove forming surface is formed by the first surface of the electromagnetic steel plate that is arranged vertically downward, and the second groove forming surface is formed by the groove forming surface portion of the electromagnetic steel plate that is arranged vertically upward. 6. The electric motor according to claim 5 ,
An electric motor characterized in that the thickness of the electromagnetic steel plate is set within a range of 0.25 mm to 0.35 mm, the length of the groove forming surface portion along the plate thickness direction is set within a range of 0.03 mm to 0.08 mm, and the length of the groove forming surface portion from the passage forming surface portion along the extension direction of the second surface is set within a range of 0.05 mm to 0.15 mm. The compressor includes a sealed container, a compression mechanism that compresses a refrigerant, and an electric motor that drives the compression mechanism.
The sealed container has an inner peripheral surface and an inner space formed by the inner peripheral surface of the sealed container,
The compression mechanism and the electric motor are housed in the sealed container inner space such that the electric motor is disposed vertically above the compression mechanism,
A compressor, comprising the electric motor according to any one of claims 1 to 4 as the electric motor.

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