JP7170855B2 - Electric motor stators, electric motors, hermetic compressors and refrigeration cycle devices - Google Patents

Description

TECHNICAL FIELD The present invention relates to a stator for an electric motor, an electric motor, a hermetic compressor, and a refrigeration cycle device having through grooves in the core-back of the stator core.

Generally, in a hermetic electric compressor in which a compression mechanism section and an electric motor section are housed in a closed container, the electric motor section has a rotor and a stator. The rotor is connected to the compression mechanism through the main shaft. The stator is fixed to the closed container by a method such as shrink fitting. The compression mechanism section compresses the refrigerant and supplies the compressed refrigerant to a refrigeration cycle device provided outside the closed container. During the supply process of the refrigerant compressed by the compression mechanism, the refrigerant may involve the lubricating oil of the compression mechanism and pass through the space of the electric motor.

During operation of the compressor, the windings of the stator are exposed to hot gaseous refrigerant compressed in the compression mechanism. Also, the windings of the stator generate heat by the secondary current. This causes the stator windings to become hot. Therefore, the windings of the stator are objects to be cooled from the viewpoint of the heat resistance temperature of the windings or the winding resistance.

For example, while the upper limit of the discharge temperature is 115°C, the upper limit of the heat resistance temperature of the winding is 130°C. In this way, the discharge temperature of the gas refrigerant is usually controlled below the upper limit of the heat resistance temperature of the winding. One effective method for cooling the stator windings is to increase the amount of refrigerant passing through the space of the electric motor to promote heat exchange between the stator windings and the refrigerant.

2. Description of the Related Art In a motor having a stator in which a conductor such as a copper wire is wound through an insulating paper in a slot of a stator core formed by laminating a plurality of electromagnetic steel sheets, a technique of providing a coolant passage is known. The coolant passage extends through a core back, which is an annular core portion formed on the outer periphery of the stator core, along the center axis direction in proximity to the windings of the stator. The circulation of the coolant in the coolant passage allows the windings of the stator to be cooled without lowering the output of the electric motor (see, for example, Patent Document 1).

JP-A-2003-125547

However, when the technique of Patent Document 1 is applied to the stator of a hermetic compressor for a refrigerating air conditioner, the lubricating oil that has passed through the refrigerant passage together with the refrigerant is swirled up into the upper space of the hermetic container. As a result, the lubricating oil is easily taken out of the compressor together with the refrigerant, increasing the oil circulation rate in the refrigeration cycle device, and reducing the reliability of the compressor due to the depletion of oil in the hermetic compressor. be.

SUMMARY OF THE INVENTION The present invention is intended to solve the above-mentioned problems, and it is possible to suppress the take-out of lubricating oil to the outside of the compressor while maintaining the function of cooling the windings of the stator, and to ensure the reliability of the compressor. An object of the present invention is to provide a stator for an electric motor, an electric motor, a hermetic compressor, and a refrigeration cycle device.

A stator for an electric motor according to the present invention has a plurality of teeth on the circumference, a stator core having slots formed between the adjacent teeth, windings wound around the teeth, and the windings. An insulating film that insulates between the wire and the inner circumference of the slot, and a lower end insulator that insulates between the winding and the lower end of the teeth in the central axis direction of the distributed circumference of the plurality of teeth. and an upper end insulator that insulates between the winding and upper ends of the teeth in the central axis direction, and the stator core is in contact with the insulating film outside the slots in the circumferential direction. A contact surface portion of the core back with the insulating film has a through groove extending to both ends in the vertical direction along the central axis direction, and the lower end insulator communicates with the through groove to extend vertically. The upper end insulator has a partition surface portion that blocks upward penetration of the through groove , and the extending angle of the first communication groove of the lower end insulator is It has an inclination of a predetermined angle with respect to the central axis direction in which the through groove extends .

An electric motor according to the present invention includes the above-described electric motor stator.

A hermetic compressor according to the present invention includes the electric motor described above.

A refrigeration cycle apparatus according to the present invention includes the hermetic compressor described above.

According to the stator of the electric motor, the electric motor, the hermetic compressor, and the refrigerating cycle device according to the present invention, the contact surface portion of the core back with the insulating film has through grooves extending vertically along the central axis direction. The lower end insulator has first communication grooves that are in communication with the through grooves and extend over both ends in the vertical direction. The upper end insulator has a partition surface portion that partitions upward penetration of the through groove. As a result, the coolant that has flowed from the first communication groove into the through groove cools the windings of the stator. On the other hand, the coolant that has flowed into the through groove is blocked by the partition surface from penetrating upward from the through groove in the upper end insulator, and the lubricating oil that has flowed into the through groove together with the coolant is prevented from flowing out upward from the partition surface. can be prevented. Therefore, it is possible to suppress the lubricating oil from being taken out of the compressor while maintaining the function of cooling the windings of the stator, thereby ensuring the reliability of the compressor.

1 is an explanatory diagram showing a vertical cross section of a hermetic compressor according to Embodiment 1. FIG. 1 is an explanatory diagram showing a cross section of an electric motor according to Embodiment 1; FIG. 4 is a bottom end view showing the stator of the electric motor according to Embodiment 1 as viewed from below where the compression mechanism is arranged; FIG. 3 is a bottom end view showing the stator core according to Embodiment 1 as viewed from below where a compression mechanism is arranged; FIG. 4 is a correlation diagram showing windings and through grooves according to Embodiment 1. FIG. FIG. 2 is a perspective view showing the stator core before the windings and insulating films according to the first embodiment are mounted; FIG. 5 is an explanatory view showing the stator core according to Embodiment 1 in a vertical cross section taken along line AA of FIG. 4; 8 is an enlarged view showing part of the stator core according to Embodiment 1 in the A1 area of FIG. 7; FIG. FIG. 9 is a perspective view showing a stator core before installation of windings and insulating films according to Embodiment 2; FIG. 9 is a correlation diagram showing an angle θ formed between a through groove and a first communication groove according to Embodiment 2; FIG. 11 is a correlation diagram showing Wmin and W in the tee score according to Embodiment 3; FIG. 5 is an explanatory view showing the stator core according to Embodiment 4 in a vertical cross section taken along line AA in FIG. 4; FIG. 13 is an enlarged view showing part of the stator core according to Embodiment 4 in the A2 area of FIG. 12; FIG. 11 is a refrigerant circuit diagram showing a refrigeration cycle device to which a hermetic compressor according to Embodiment 5 is applied;

Embodiments are described below on the basis of the drawings. In addition, in each figure, the same reference numerals denote the same or corresponding parts, and this is common throughout the specification. Also, in the cross-sectional drawings, hatching is appropriately omitted in view of visibility. Furthermore, the forms of components shown in the entire specification are merely examples and are not limited to these descriptions.

Embodiment 1.
<Configuration of Hermetic Compressor 100>
FIG. 1 is an explanatory view showing a vertical cross section of a hermetic compressor 100 according to Embodiment 1. FIG. Here, in the following description, the illustrated U is upward and D is downward. As shown in FIG. 1 , the hermetic compressor 100 includes a hermetic container 1 , a compression mechanism section 2 and an electric motor 3 .

<Structure of closed container 1>
The sealed container 1 forms the outer shell of the sealed compressor 100 and has an oil reservoir 1a for storing lubricating oil at the bottom. A compression mechanism section 2 is arranged in the lower part of the closed container 1 . An electric motor 3 is arranged in the upper part of the closed container 1 .

The sealed container 1 is composed of a cylindrical central container 11 and upper and lower containers 12 and 13 which are fitted into upper and lower openings of the central container 11 in a sealed state.

A suction pipe 15 having a suction muffler 14 in the middle is connected to the central container 11 . The suction pipe 15 is a connecting pipe that feeds the inflowing low-temperature, low-pressure gas refrigerant into the compression mechanism portion 2 .

A discharge pipe 16 is connected to the upper container 12 . The discharge pipe 16 is a connecting pipe that allows the refrigerant in the sealed container 1 compressed by the compression mechanism 2 to flow into the refrigerant pipe.

Refrigerant sucked from a suction pipe 15 having a suction muffler 14 is compressed to a high pressure by the compression mechanism section 2 and discharged from a discharge pipe 16 to the outside of the compressor.

<Configuration of Compression Mechanism 2>
The compression mechanism section 2 has a rotating shaft 21, a main bearing 22, a sub-bearing 23, a rolling piston 24, a cylindrical cylinder 25, and vanes (not shown). The rotating shaft 21 is fixed to the rotor 32 of the electric motor 3 . A rotating shaft 21 is held by a main bearing 22 and a sub-bearing 23 . The rolling piston 24 is fixed to the rotating shaft 21 and accommodated in the cylindrical cylinder 25 so as to be eccentrically rotatable. The inside of the cylindrical cylinder 25 is divided into compression chambers by vanes. The vanes follow the movement of the rolling piston 24 to move the compression chamber. As a result, the high pressure refrigerant in the compression chamber is delivered from the compression mechanism 2 to the space inside the sealed container 1 .

Refrigerant sent from the compression mechanism 2 passes through the gap of the electric motor 3 and is discharged outside the compressor from a discharge pipe 16 connected to the upper container 12 . At this time, the lubricating oil is swirled up together with the refrigerant in the upward direction U where the upper container 12 exists. A part of the lubricating oil is carried out of the compressor through the discharge pipe 16 .

<Configuration of electric motor 3>
FIG. 2 is an explanatory diagram showing a cross section of the electric motor 3 according to the first embodiment. FIG. 3 is a bottom end view showing the stator 31 of the electric motor 3 according to Embodiment 1 as viewed from the downward direction D in which the compression mechanism portion 2 is arranged. FIG. 4 is a bottom end view showing the stator core 301 according to Embodiment 1 as viewed from the downward direction D in which the compression mechanism section 2 is arranged.

As shown in FIG. 2, the electric motor 3 is a brushless DC motor. The electric motor 3 has a stator 31 and a rotor 32 .

The rotor 32 is arranged inside the stator 31 . The rotor 32 is a 6-pole permanent magnet rotor, and is an embedded permanent magnet rotor in which permanent magnets are inserted into magnet insertion holes.

As shown in FIGS. 1, 2, 3 and 4, the stator 31 includes a stator core 301, windings 302, insulating films 303, lower end insulators 304, and upper end insulators 305. Prepare.

As shown in FIG. 2, the stator core 301 has a plurality of tee cores 301a, which are divided cores distributed on the circumference. The plurality of tee scores 301a are annularly arranged with the rotation axis 21 as the central axis. That is, the central axis means the central axis of the distributed circumference of the plurality of teeth 301b.

Teeth core 301a is provided with teeth 301b that extend inward in the direction of the central axis. A slot 301c is formed between two adjacent teeth 301b. The stator core 301 has core backs 301d circumferentially outside the slots 301c. A plurality of core backs 301d are arranged in the circumferential direction and form an outer shell of the stator core 301 made up of a plurality of annularly arranged tooth cores 301a.

The tooth core 301a is formed by laminating a predetermined number of thin electromagnetic steel sheets having a thickness of 0.25 mm, for example, punched into a predetermined shape, and fixing them by caulking or the like. Note that the stator core 301 may be an integral core in which each tea core is integrally formed. The stator core 301 may also have a joint-wrap structure in which the tooth cores 301a are rotatably connected by caulking made by forming unevenness on the electronic steel plate between the two adjacent teeth 301b in the core back 301d. good.

As shown in FIGS. 2, 3 and 4, the windings 302 are wound around the teeth 301b. Winding 302 is an electrically conductive wire. Specifically, the winding 302 is wound around the body of the tooth 301b surrounded by the tooth core 301a, the insulating film 303, the lower end insulator 304, and the upper end insulator 305 without winding disorder.

Insulating film 303 insulates stator core 301 and windings 302 . Specifically, the insulating film 303 provides insulation between the winding 302 and the inner periphery of the slot 301c.

The insulating film 303 is composed of, for example, a PET (polyethylene terephthalate) film. The insulating film 303 is fixed by a method such as fitting, adhesion, or welding in which grooves for sandwiching the PET film are provided in the lower end insulator 304 and the upper end insulator 305 . The thickness of the insulating film 303 is as thin as about 0.1 to 0.2 mm. Therefore, the cross-sectional area of the insulating film 303 that occupies the area of the slot 301c is very small. As a result, the insulating film 303 can wind many windings 302 .

As shown in FIGS. 1, 3 and 4, the lower end insulator 304 insulates between the winding 302 and the lower end of the teeth 301b in the central axis direction. The lower end insulator 304 is arranged in the downward direction D of the stator core 301 on the side of the compression mechanism section 2 .

As shown in FIG. 1, the upper end insulator 305 provides insulation between the winding 302 and the upper end of the teeth 301b in the central axis direction. Upper end insulator 305 is located on the opposite side of lower end insulator 304 across stator core 301 .

The lower end insulator 304 and the upper end insulator 305 are made of LCP (liquid crystal polymer), for example. The lower end insulator 304 and the upper end insulator 305 are fixed to the end of the tooth core 301a by fitting, bonding, welding, or the like.

<Cooling structure of winding 302>
FIG. 5 is a correlation diagram showing the winding 302 and the through groove 301a-1 according to the first embodiment. FIG. 6 is a perspective view showing the stator core 301 before mounting the windings 302 and the insulating films 303 according to the first embodiment. FIG. 7 is an explanatory diagram showing the stator core 301 according to Embodiment 1 in a vertical cross section taken along line AA in FIG. FIG. 8 is an enlarged view showing part of the stator core 301 according to Embodiment 1 in the A1 area of FIG.

As shown in FIGS. 2, 5, 6, 7 and 8, the contact surface portion of the core back 301d with the insulating film 303 extends through both ends in the upward direction U and the downward direction D along the central axis direction. It has a groove 301a-1.

As shown in FIG. 6, the through groove 301a-1 is linear with a constant width along the central axis direction. A plurality of through grooves 301a-1 are arranged in parallel.

As shown in FIG. 2, a plurality of through grooves 301a-1 in one stator core 301 extend radially outward from the central axis at the center of the winding portion of winding 302, which is the center of tooth 301b. It is configured line-symmetrically with respect to the imaginary center line T. Here, four through grooves 301a-1 are provided on one side of the imaginary center line T in the contact surface portion with the insulating film 303 of the core back 301d of the tea core 301a.

As shown in FIG. 5, the width B of the through groove 301a-1 in the circumferential direction perpendicular to the central axis direction is smaller than the diameter 2R of the winding 302. As shown in FIG. That is, the relationship B<2R is satisfied.

As shown in FIGS. 3, 4, 6 and 7, the lower end insulator 304 has a first communicating groove 304-1 extending in the upward direction U and the downward direction D in communication with the through groove 301a-1. have. The first communication groove 304-1 matches the groove shape of the through groove 301a-1 at the junction between the lower end insulator 304 and the tooth core 301a.

As shown in FIGS. 6, 7 and 8, the upper end insulator 305 has a lower end surface portion 305a which is a partition surface portion blocking penetration in the upward direction U of the through groove 301a-1. That is, the partition surface portion is formed as part of the one-planar lower end surface portion 305 a of the upper end insulator 305 . A lower end face portion 305a of the upper end insulator 305 has no groove and closes the through groove 301a-1. Specifically, the through groove 301a-1 is interrupted and closed at the junction between the upper end insulator 305 and the tooth core 301a.

<Action>
Refrigerant and lubricating oil delivered to the space in the sealed container 1 by the compression mechanism 2 are introduced from the downward direction D into the first communication groove 304-1 provided in the lower end insulator 304. As shown in FIG. The refrigerant and lubricating oil introduced into the first communication groove 304-1 pass through the through groove 301a-1 provided in the tooth core 301a. Thereby, the tooth core 301a and the winding 302 can be cooled by the coolant. In addition, the upper end insulator 305 blocks the outlet in the upward direction U of the refrigerant and lubricating oil flowing through the through groove 301a-1. Therefore, the lubricating oil flowing through the through groove 301a-1 is not swirled up into the upper space of the sealed container 1, and an increase in the oil circulation rate can be suppressed.

Further, the number of the through grooves 301a-1 of the tooth core 301a and the number of the first communication grooves 304-1 of the lower end insulator 304 are plural. As a result, the insulating film 303 spreads across the plurality of grooves, and the insulating film 303 can be pressed into the plurality of grooves by the windings 302 and held securely. At the same time, the pitch, which is the width B of each groove, can be reduced, making it difficult for the winding wire 302 to enter the through groove 301a-1 and the first communication groove 304-1. As a result, high-density windings 302 can be formed while maintaining alignment, and the electric motor 3 can be configured with higher efficiency.

Furthermore, the capacitance C between the winding 302 and the stator core 301 has the following relationship. That is, the dielectric constant between the winding 302 and the stator 31 is ε, the contact area between the winding 302 and the stator 31 is S, and the distance between the winding 302 and the stator 31 is d. . At this time, the relationship C=εS/d holds. That is, when a thin insulating material such as a PET film is used for the insulating film 303, the distance d between the windings 302 and the stator 31 is reduced and the capacitance C is increased. Assuming that the leakage current is i, the relationship i∝C holds. For this reason, when the capacitance C increases, leakage current is likely to flow.

However, in the stator core 301, a gap is secured between the tooth core 301a and the winding 302 by the through groove 301a-1. As a result, the contact area between the windings 302 and the stator core 301 is reduced, the distance between the windings 302 and the stator core 301 is increased, and the floating static electricity between the windings 302 and the stator core 301 is increased. Electric capacity can be reduced.

<Effect of Embodiment 1>
According to Embodiment 1, the stator 31 of the electric motor 3 includes a stator core 301 having a plurality of teeth 301b distributed on the circumference and having slots 301c formed between adjacent teeth 301b. A stator 31 of the electric motor 3 includes windings 302 wound around teeth 301b. The stator 31 of the electric motor 3 has an insulation film 303 that insulates between the windings 302 and the inner circumference of the slot 301c. The stator 31 of the electric motor 3 includes a lower end insulator 304 that insulates between the windings 302 and the lower ends of the teeth 301b in the central axis direction of the distributed circumference of the plurality of teeth 301b. The stator 31 of the electric motor 3 includes an upper end insulator 305 that insulates between the windings 302 and the upper ends of the teeth 301b in the central axis direction of the distributed circumference of the plurality of teeth 301b. The stator core 301 has an arcuate core back 301d that contacts the insulating film 303 on the outer side of the slot 301c in the circumferential direction. A contact surface portion of the core back 301d with the insulating film 303 has a through groove 301a-1 extending over both ends in the upward direction U and the downward direction D along the central axis direction. The lower end insulator 304 has a first communication groove 304-1 extending in both the upward direction U and the downward direction D in communication with the through groove 301a-1. The upper end insulator 305 has a lower end surface portion 305a which is a partition surface portion blocking penetration in the upward direction U of the through groove 301a-1.

According to this configuration, the coolant flowing from the first communication groove 304-1 into the through groove 301a-1 cools the windings 302 of the stator 31. As shown in FIG. On the other hand, the coolant that has flowed into the through groove 301a-1 is blocked from penetrating in the upward direction U from the through groove 301a-1 in the upper end insulator 305 by the lower end surface portion 305a. In other words, it is possible to prevent the lubricating oil, which has flowed into the through groove 301a-1 together with the refrigerant, from flowing out in the upward direction U from the lower end face portion 305a. Therefore, while maintaining the function of cooling the windings 302 of the stator 31, it is possible to suppress the lubricating oil from being taken out of the compressor, and the reliability of the hermetic compressor 100 can be ensured. In addition, the through groove 301a-1 is provided in the core back 301d, and the distance between the winding 302 and the stator core 301 in the core back 301d can be secured, and even if the thin insulating film 303 is interposed, the stray capacitance can be maintained. can be reduced.

According to Embodiment 1, the partition surface is lower end surface 305 a of upper end insulator 305 .

According to this configuration, the one-planar lower end surface portion 305a of the upper end insulator 305 also serves as a partition surface portion, and the machining of the upper end insulator 305 is minimized.

According to Embodiment 1, the through groove 301a-1 is linear with a constant width along the central axis direction.

According to this configuration, it is sufficient to form the portions of the through grooves 301a-1 in the same shape in each magnetic steel sheet with respect to the electromagnetic steel sheets in which the teeth 301b are stacked, and the stator 31 can be easily manufactured.

According to Embodiment 1, a plurality of through grooves 301a-1 are arranged.

According to this configuration, the coolant that has flowed from the plurality of first communication grooves 304-1 into the plurality of through grooves 301a-1 cools the windings 302 of the stator 31. FIG. As a result, the cooling effect on the windings 302 of the stator 31 can be obtained over a wide area of the core back 301d.

According to Embodiment 1, the plurality of through-grooves 301a-1 are arranged line-symmetrically with respect to the imaginary center line T extending radially outward from the central axis at the center of the winding portion of the winding 302. ing.

According to this configuration, the coolant flowing from the plurality of first communication grooves 304-1 to the plurality of through grooves 301a-1 cools the windings 302 of the stator 31 in a line-symmetrical manner with good balance with respect to the virtual center line T. do. As a result, the cooling effect on the windings 302 of the stator 31 can be obtained more effectively in the wide area of the core back 301d.

According to the first embodiment, width B of through groove 301 a - 1 in the direction perpendicular to the central axis direction is smaller than diameter R 2 of winding 302 .

According to this configuration, the winding 302 does not get stuck in the through groove 301a-1, and the winding of the winding 302 is facilitated.

According to Embodiment 1, the electric motor 3 includes the stator 31 of the electric motor 3 described above.

According to this configuration, since the electric motor 3 includes the stator 31 of the electric motor 3, it is possible to suppress the lubricating oil from being taken out of the compressor while maintaining the function of cooling the windings 302 of the stator 31. The reliability of the hermetic compressor 100 can be secured.

According to Embodiment 1, hermetic compressor 100 includes electric motor 3 described above.

According to this configuration, since the hermetic compressor 100 includes the electric motor 3, it is possible to suppress the lubricating oil from being taken out of the compressor while maintaining the function of cooling the windings 302 of the stator 31. The reliability of the type compressor 100 can be secured.

Embodiment 2.
FIG. 9 is a perspective view showing the stator core 301 before the windings 302 and the insulating films 303 are attached according to the second embodiment. FIG. 10 is a correlation diagram showing the angle θ between the through groove 301a-1 and the first communication groove 304-1 according to the second embodiment. In the second embodiment, descriptions of the same items as in the first embodiment are omitted, and only the characteristic portions are described.

As shown in FIG. 9, the extending angle θ of the first communication groove 304-1 of the lower end insulator 304 is inclined at a predetermined angle with respect to the central axis direction of the extending through groove 301a-1. Specifically, the extending angle θ of the first communication groove 304-1 of the lower end insulator 304 is the angle at which the winding 302 is separated from the winding portion of the winding 302 with respect to the central axis direction of the extending through groove 301a-1. has a slope of However, the first communication groove 304-1 communicates with the through groove 301a-1 and has the same groove shape.

In Embodiment 1 shown in FIG. 6, the first communication groove 304-1 of the lower end insulator 304 is provided parallel to the central axis direction. Therefore, the insulating film 303 may enter the first communication groove 304 - 1 of the lower end insulator 304 . Therefore, when the winding 302 is wound in the central axis direction, there is a possibility that the winding 302 enters the first communication groove 304-1 into which the insulating film 303 has entered.

In contrast, in the lower end insulator 304 of the second embodiment, the first communication groove 304-1 has an angle θ with respect to the central axis direction. Therefore, the winding 302 is less likely to enter the first communication groove 304-1 when the winding 302 is wound. For example, the angle at which the first communication groove 304-1 of the lower end insulator 304 extends is θ, and the angle at which the through groove 301a-1 extends in the central axis direction is 180°. At this time, it is preferable that 150°≦θ<180° is satisfied.

<Effect of Embodiment 2>
According to the second embodiment, the extension angle θ of first communication groove 304-1 of lower end insulator 304 is inclined at a predetermined angle with respect to the central axis direction of extension of through groove 301a-1.

According to this configuration, the winding 302 is less likely to enter the first communication groove 304-1 when winding the winding 302, and the winding of the winding 302 is facilitated.

According to Embodiment 2, the angle θ at which first communication groove 304-1 of lower end insulator 304 extends is spaced apart from the winding portion of winding 302 with respect to the direction of the central axis in which through groove 301a-1 extends. It has a slope of an increasing angle.

According to this configuration, the extension angle θ of the first communication groove 304-1 is opposite to the direction of the winding 302, so that the winding 302 extends through the first communication groove 304-1 when the winding 302 is wound. It becomes more difficult to get in, and the winding of the winding 302 becomes easier.

According to the second embodiment, if the angle at which first communication groove 304-1 of lower end insulator 304 extends is θ and the angle at which through groove 301a-1 extends in the central axis direction is 180°, then 150°. °≦θ<180° is satisfied.

According to this configuration, the angle θ at which the first communication groove 304-1 extends can be set to an optimum range opposite to the direction of the winding 302, and the winding 302 is in the first communication when the winding 302 is wound. The groove 304-1 makes it difficult to get into the winding, making it easier to wind the winding 302. FIG.

Embodiment 3.
FIG. 11 is a correlation diagram showing Wmin and W in tea score 301a according to the third embodiment. In Embodiment 3, descriptions of the same items as in Embodiments 1 and 2 are omitted, and only the characteristic portions thereof are described.

The stator core 301 serves as a magnetic path through which the magnetic field received from the rotor 32 passes. However, when the through groove 301a-1 is provided in the stator core 301, the magnetic path in the core back 301d is narrowed, and the magnetic characteristics are deteriorated.

Here, the ease with which the magnetic flux passes through the core back 301d is determined by the narrowest portion Wmin of the radial width of the core back 301d shown in FIG. Therefore, the radial width of the portion of the core back 301d where the through groove 301a-1 is formed is W, and the width of the narrowest portion of the core back 301d in the radial direction is Wmin. At this time, W≧Wmin is satisfied.

As a result, a large gap can be obtained between the stator core 301 and the windings 302 . For example, when Wmin is the core split plane as shown in FIG. 11, the outermost diameter of the through groove 301a-1 may be formed on the arc passing through the inner intersection of the core split plane or inside the arc. As a result, the magnetic properties are not greatly impaired, the cooling effect of the stator 31 and the effect of reducing the floating capacitance are further improved, and the electric motor 3 excellent in terms of efficiency can be configured.

<Effect of Embodiment 3>
According to Embodiment 3, in the stator 31 of the electric motor 3, the radial width of the portion of the core back 301d where the through groove 301a-1 is formed is W, and the radial width of the core back 301d is the narrowest. Let Wmin be the width of the portion. At this time, W≧Wmin is satisfied.

The ease with which magnetic flux passes through the core back 301d is determined by the narrowest portion Wmin of the radial width of the core back 301d. According to this configuration, W≧Wmin is satisfied, where W is the radial width of the portion of the core back 301d where the through groove 301a-1 is formed. Therefore, there is no place in the core back 301d where the magnetic flux is less likely to pass than Wmin, and the magnetic properties of the core back 301d are not greatly impaired. In addition, the through groove 301a-1 can be formed deep within the range where W≧Wmin is satisfied, and the effect of cooling the stator 31 and the effect of reducing the stray capacitance can be further improved. As described above, the electric motor 3 having excellent efficiency can be configured.

Embodiment 4.
FIG. 12 is an explanatory view showing the stator core 301 according to Embodiment 4 in a vertical cross section taken along line AA in FIG. FIG. 13 is an enlarged view showing part of the stator core 301 according to Embodiment 4 in the A2 area of FIG. 12. As shown in FIG. In the fourth embodiment, descriptions of the same items as in the first, second, and third embodiments are omitted, and only the characteristic portions are described. In Embodiments 1, 2, and 3, only the lower end insulator 304 on the side of the compression mechanism is provided with the coolant introduction groove. However, for example, the upper end insulator 305 on the opposite side may also be provided with grooves whose shape or number is adjusted. However, the groove of the upper end insulator 305 needs to be closed by the partition surface.

As shown in FIGS. 12 and 13, the upper end insulator 305 has a second communication groove 305- formed halfway between the upward direction U and the downward direction D of the upper end insulator 305 in communication with the through groove 301a-1. 1. The second communication groove 305-1 is formed upward in the U direction from the winding portion of the winding 302. As shown in FIG.

As shown in FIG. 13, the partition surface is the upper groove end surface 305b of the second communication groove 305-1. The upper groove end surface portion 305b has a flat surface along the horizontal direction. An opening 305c is formed between the upper groove end surface 305b, which is a partition surface, and the winding portion of the winding 302. The opening 305c is open in a direction orthogonal to the central axis direction along the upward direction U and the downward direction D. It is The opening 305c allows the outlet of the coolant to be formed in the horizontal direction. Therefore, the circulation rate of the coolant is increased, and the cooling effect of the stator 31 is further improved.

<Effect of Embodiment 4>
According to the fourth embodiment, upper end insulator 305 has second communication groove 305-1 formed halfway between upper end insulator 305 in upward direction U and downward direction D in communication with through groove 301a-1. have.

According to this configuration, since the coolant flowing through the through groove 301a-1 reaches the second communication groove 305-1 of the upper end insulator 305, the winding 302 wound up to the upper end insulator 305 is also cooled. is obtained.

According to Embodiment 4, the second communication groove 305-1 is formed upward in the U direction from the winding portion of the winding 302. As shown in FIG. The partition surface is the upper groove end surface 305b of the second communication groove 305-1.

According to this configuration, since the coolant flowing through the through groove 301a-1 reaches the second communication groove 305-1 formed upward in the U direction from the winding portion of the winding 302, the coolant is wound up to the upper end insulator 305. A cooling effect is obtained for all of the windings 302 that are connected. In addition, since the partition surface portion is the upper groove end surface portion 305b of the second communication groove 305-1, the lubricating oil that has flowed into the through groove 301a-1 together with the refrigerant flows upward in the U direction from the upper groove end surface portion 305b, which is the partition surface portion of the lubricating oil. outflow can be prevented.

According to the fourth embodiment, an opening 305c that is open in a direction orthogonal to the central axis direction is formed between the upper groove end surface 305b, which is the partition surface, and the winding portion of the winding 302. .

According to this configuration, the refrigerant and lubricating oil that have risen in the upward direction U to the second communication groove 305-1 are directed to the opening 305c that is open in the direction orthogonal to the central axis direction instead of the upward direction U, and the lubricating oil can be prevented from flowing out in the upward direction U. In addition, the refrigerant and lubricating oil that have risen in the upward direction U to the second communication groove 305-1 do not need to descend again through the through groove 301a-1 and the first communication groove 304-1. That is, the refrigerant and lubricating oil that have risen in the upward direction U to the second communication groove 305-1 are discharged around the electric motor 3 through the opening 305c. That is, the coolant and the lubricating oil efficiently circulate in this order through the first communication groove 304-1, the through groove 301a-1, and the second communication groove 305-1, and the winding of the stator 31 is prevented without the lubricating oil accumulating in the middle. The cooling effect of the wire 302 is obtained efficiently.

In addition, Embodiment 1, Embodiment 2, Embodiment 3, and Embodiment 4 may be combined or applied to other parts.

Embodiment 5.
<Refrigeration cycle device 101>
FIG. 14 is a refrigerant circuit diagram showing a refrigeration cycle device 101 to which the hermetic compressor 100 according to Embodiment 5 is applied.

As shown in FIG. 14 , a refrigeration cycle device 101 includes a hermetic compressor 100 , a condenser 102 , an expansion valve 103 and an evaporator 104 . These hermetic compressor 100, condenser 102, expansion valve 103 and evaporator 104 are connected by refrigerant pipes to form a refrigerant circuit. The refrigerant that has flowed out of the evaporator 104 is sucked into the hermetic compressor 100 and becomes high temperature and high pressure. The high-temperature and high-pressure refrigerant is condensed in the condenser 102 to become a liquid. The liquid refrigerant is decompressed and expanded by the expansion valve 103 to become a low-temperature, low-pressure gas-liquid two-phase refrigerant.

The hermetic compressors 100 of Embodiments 1, 2, 3, and 4 can be applied to such a refrigeration cycle device 101 . In addition, as the refrigerating cycle device 101, for example, an air conditioner, a refrigerating device, a water heater, or the like can be mentioned.

<Effect of Embodiment 5>
According to Embodiment 5, refrigeration cycle apparatus 101 includes hermetic compressor 100 described above.

According to this configuration, since the refrigeration cycle device 101 includes the hermetic compressor 100, it is possible to suppress the lubricating oil from being carried out of the compressor while maintaining the function of cooling the windings 302 of the stator 31. , the reliability of the hermetic compressor 100 can be ensured.

Reference Signs List 1 sealed container 1a oil reservoir 2 compression mechanism 3 electric motor 11 central container 12 upper container 13 lower container 14 suction muffler 15 suction pipe 16 discharge pipe 21 rotating shaft 22 main bearing 23 Auxiliary Bearing 24 Rolling Piston 25 Cylindrical Cylinder 31 Stator 32 Rotor 100 Hermetic Compressor 101 Refrigeration Cycle Device 102 Condenser 103 Expansion Valve 104 Evaporator 301 Stator Core 301a Tee Core , 301a-1 through groove, 301b tooth, 301c slot, 301d core back, 302 winding, 303 insulating film, 304 lower end insulator, 304-1 first communication groove, 305 upper end insulator, 305-1 second communication groove , 305a lower end face, 305b upper groove end face, 305c opening.

Claims (16)

a stator core having a plurality of teeth on its circumference and having slots formed between adjacent teeth;
a winding wound around the teeth;
an insulating film that insulates between the winding and the inner periphery of the slot;
a lower end insulator that insulates between the winding and a lower end portion of the plurality of teeth in the central axis direction of the distributed circumference of the teeth;
an upper end insulator that insulates between the winding and upper ends of the teeth in the central axis direction;
with
The stator core has a core back that contacts the insulating film outside the slots in the circumferential direction,
A contact surface portion of the core back with the insulating film has a through groove extending to both ends in the vertical direction along the central axis direction,
The lower end insulator has a first communication groove extending to both ends in the vertical direction and communicating with the through groove,
The upper end insulator has a partition surface that blocks upward penetration of the through groove ,
A stator for an electric motor in which the extending angle of the first communication groove of the lower end insulator is inclined at a predetermined angle with respect to the central axis direction in which the through groove extends . a stator core having a plurality of teeth on its circumference and having slots formed between adjacent teeth;
a winding wound around the teeth;
an insulating film that insulates between the winding and the inner periphery of the slot;
a lower end insulator that insulates between the winding and a lower end portion of the plurality of teeth in the central axis direction of the distributed circumference of the teeth;
an upper end insulator that insulates between the winding and upper ends of the teeth in the central axis direction;
with
The stator core has a core back that contacts the insulating film outside the slots in the circumferential direction,
A contact surface portion of the core back with the insulating film has a through groove extending to both ends in the vertical direction along the central axis direction,
The lower end insulator has a first communication groove extending to both ends in the vertical direction and communicating with the through groove,
The upper end insulator has a partition surface that blocks upward penetration of the through groove,
The angle at which the first communication groove of the lower end insulator extends is such that the angle with respect to the direction of the central axis at which the through groove extends is such that the angle increases away from the winding portion of the winding. stator. 3. The stator for an electric motor according to claim 1, wherein the partition surface portion is a lower end surface portion of the upper end insulator. The stator for an electric motor according to any one of claims 1 to 3 , wherein the through groove is straight with a constant width along the direction of the central axis. 150°≦θ<180°, where θ is the angle at which the first communication groove of the lower end insulator extends, and θ is 180° at which the through groove extends in the direction of the central axis. A stator for an electric motor according to any one of claims 1 to 4 . Where W is the width of the portion of the core-back in the radial direction where the through groove is formed, and Wmin is the width of the narrowest portion of the core-back in the radial direction, W≧Wmin is satisfied. A stator for an electric motor according to claim 5 . a stator core having a plurality of teeth on its circumference and having slots formed between adjacent teeth;
a winding wound around the teeth;
an insulating film that insulates between the winding and the inner periphery of the slot;
a lower end insulator that insulates between the winding and a lower end portion of the plurality of teeth in the central axis direction of the distributed circumference of the teeth;
an upper end insulator that insulates between the winding and upper ends of the teeth in the central axis direction;
with
The stator core has a core back that contacts the insulating film outside the slots in the circumferential direction,
A contact surface portion of the core back with the insulating film has a through groove extending to both ends in the vertical direction along the central axis direction,
The lower end insulator has a first communication groove extending to both ends in the vertical direction and communicating with the through groove,
The upper end insulator has a partition surface that blocks upward penetration of the through groove, and a second communication groove that communicates with the through groove and is formed halfway in the vertical direction of the upper end insulator. Motive stator. The second communication groove is formed upward from the winding portion of the winding,
8. A stator for an electric motor according to claim 7 , wherein said partition surface portion is an upper groove end surface portion of said second communication groove. 9. A stator for an electric motor according to claim 8 , wherein an opening opened in a direction orthogonal to the direction of the central axis is formed between the partition surface portion and the winding portion of the winding. The stator for an electric motor according to any one of claims 1 to 9 , wherein a plurality of said through grooves are arranged. 11. The electric motor according to claim 10 , wherein the plurality of through grooves are arranged line-symmetrically with respect to an imaginary center line extending radially outward from the central axis at the center of the winding portion of the winding. stator. The stator for an electric motor according to any one of claims 1 to 11 , wherein a width of said through groove in a direction orthogonal to said central axis direction is smaller than a diameter of said winding. The stator for an electric motor according to any one of claims 1 to 12 , which is used for an electric motor of a refrigeration cycle device. An electric motor comprising the electric motor stator according to any one of claims 1 to 13 . A hermetic compressor comprising the electric motor according to claim 14 . A refrigeration cycle apparatus comprising the hermetic compressor according to claim 15 .

Images