Rotor, electric motor, hermetic compressor, and refrigeration cycle device

Abstract

This rotor comprises: a rotor core formed by laminating a plurality of steel plates; a magnet insertion hole formed in an axial direction of the rotor core; a permanent magnet placed in the magnet insertion hole; mounting members respectively disposed on both axial ends of the rotor core and preventing the permanent magnet from popping out from the magnet insertion hole; a distortion suppression member placement hole formed in the axial direction of the rotor core and placed to a radially outer side from the permanent magnet with reference to an axial center of the rotor core; and a non-magnetic distortion suppression member placed inside the distortion suppression member placement hole and fixed, at both ends thereof, to the mounting members, wherein the distortion suppression member is in contact with a radial inner surface of the distortion suppression member placement hole and formed in a plate shape longer in a radial direction than in a circumferential direction in a plan view.

Description

Rotor, electric motor, hermetic compressor, and refrigeration cycle device

[0001] The present disclosure relates to a rotor, an electric motor, a hermetic compressor, and a refrigeration cycle device.

[0002] Generally, rotors for rotating electric machines have permanent magnets placed in the magnet insertion sections of the rotor core, and in order to prevent the rotor core from being distorted by the centrifugal force of the permanent magnets, support rods are pressed against the edges of the hollow section formed in the rotor core and fixed to end plates located on both ends of the rotor core, so that the centrifugal force of the permanent magnets is supported by the support rods (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2004-254466

[0004] However, in Patent Document 1, the cross-sectional shape of the support rod is round or circumferentially elongated, which means that it cannot properly absorb the centrifugal force of the permanent magnet, and therefore there is a problem in that it is not possible to sufficiently suppress distortion of the rotor core due to the centrifugal force of the permanent magnet.

[0005] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a rotor, an electric motor, a hermetic compressor, and a refrigeration cycle device that can suppress distortion of the rotor core due to the centrifugal force of the permanent magnet more than conventional methods.

[0006] The rotor according to the present disclosure comprises a rotor core formed by stacking a plurality of steel plates, a magnet insertion hole formed in the axial direction of the rotor core, a permanent magnet arranged in the magnet insertion hole, mounting members provided at both ends of the rotor core in the axial direction to prevent the permanent magnet from jumping out of the magnet insertion hole, a distortion suppression member arrangement hole formed in the axial direction of the rotor core and arranged radially outward of the permanent magnet with respect to the axis of the rotor core, and a non-magnetic distortion suppression member arranged within the distortion suppression member arrangement hole and having both ends fixed to the mounting members, wherein the distortion suppression member abuts against the radially inner side surface of the distortion suppression member arrangement hole and is formed in the shape of a plate that is longer in the radial direction than in the circumferential direction when viewed in a plane.

[0007] An electric motor according to the present disclosure includes the rotor described above and a stator that is disposed on the outer periphery of the rotor and rotates the rotor by magnetic action.

[0008] In addition, a hermetic compressor according to the present disclosure includes the above-described electric motor, a compression mechanism driven by the electric motor and compressing fluid drawn in from the outside, and a hermetic container accommodating the electric motor and the compression mechanism.

[0009] A refrigeration cycle device according to the present disclosure includes the above-described hermetic compressor, an outdoor heat exchanger, a pressure reducer, and an indoor heat exchanger.

[0010] In the rotor, electric motor, hermetic compressor, and refrigeration cycle apparatus according to the present disclosure, the strain suppression member abuts against the radially inner side surface of the strain suppression member placement hole and is formed as a plate that is longer radially than circumferentially in plan view. By arranging the strain suppression member so that it abuts against the radially inner side surface of the strain suppression member placement hole in this way, the repulsive force of the permanent magnet placed in the magnet insertion hole against the centrifugal force can be increased. Furthermore, by forming the strain suppression member into a plate shape that is longer radially than circumferentially in plan view, the section modulus is larger than that of a conventional round or circumferentially elongated shape for the same cross-sectional area, thereby improving resistance to distortion. Therefore, distortion of the rotor core due to the centrifugal force of the permanent magnet can be more effectively suppressed than in the past.

[0011] 1 is a schematic diagram showing an example of the internal configuration of a hermetic compressor according to a first embodiment; FIG. 2 is a schematic cross-sectional view of a compression mechanism of the hermetic compressor according to the first embodiment; FIG. 3 is a schematic cross-sectional view of a motor as viewed from the direction of the arrows at the AA' cross section of the hermetic compressor of FIG. 1; FIG. 4 is a schematic longitudinal cross-sectional view of a rotor as viewed from the direction of the arrows at the C-O-C' cross section of the motor of FIG. 4; FIG. 5 is a partial cross-sectional view of a rotor according to the first embodiment, enlarging the section viewed from the arrow D of the motor of FIG. 4; FIG. 6 is a partial cross-sectional view of a modified rotor according to the first embodiment, enlarging the section viewed from the arrow E of the rotor of FIG. 5; FIG. 7 is a partial cross-sectional view of a rotor according to the first embodiment, enlarging the section viewed from the arrow E of the rotor of FIG. 5; FIG. 8 is a partial cross-sectional view of a rotor according to the second embodiment, enlarging the section viewed from the arrow E of the rotor of FIG. 5; FIG. 9 is a partial cross-sectional view of a modified rotor according to the second embodiment, enlarging the section viewed from the arrow E of the rotor of FIG. 6; FIG. 10 is a partial cross-sectional view of a rotor according to a third embodiment, enlarging the section viewed from the arrow D of the motor of FIG. 4;

[0012] A hermetic compressor 100 and a refrigeration cycle apparatus 200 according to embodiments will be described below with reference to the drawings. Note that the present disclosure is not limited to the embodiments described below. Furthermore, the dimensional relationships between components in the drawings may differ from those in reality. Furthermore, in the following description, directional terms (e.g., "upper," "lower," "right," "left," "front," "rear," etc.) are used as appropriate for ease of understanding. However, these terms are for explanatory purposes and do not limit the present disclosure. Unless otherwise specified, these directional terms refer to the directions when the hermetic compressor 100 is viewed from the front side (front face). Furthermore, in each drawing, parts denoted with the same reference numerals are the same or equivalent, and this applies throughout the entire specification.

[0013] Embodiment 1 Fig. 1 is a schematic diagram showing an example of the internal configuration of a hermetic compressor 100 according to embodiment 1. Fig. 2 is a schematic cross-sectional view of a compression mechanism 20 of the hermetic compressor 100 according to embodiment 1.

[0014] The hermetic compressor 100 according to the first embodiment is a single-cylinder rotary compressor that draws in a fluid such as a refrigerant, compresses it, and discharges it in a high-temperature, high-pressure state. As shown in Fig. 1, the hermetic compressor 100 includes a hermetic container 10 that forms an outer shell. The hermetic container 10 is made up of an upper container 11 and a lower container 12.

[0015] A discharge pipe 102 is fixed to the upper surface of the upper vessel 11 of the sealed vessel 10, penetrating the upper surface. The discharge pipe 102 discharges high-pressure refrigerant gas to the outside of the sealed vessel 10. The fixed portion between the discharge pipe 102 and the upper vessel 11 is joined by, for example, welding.

[0016] A compression mechanism 20, an electric motor 30, a rotating shaft 21, and other components are housed inside the sealed container 10. The compression mechanism 20 is disposed below the sealed container 10, and the electric motor 30 is disposed above the sealed container 10. The rotating shaft 21 is disposed in the center of the sealed container 10, between the electric motor 30 and the compression mechanism 20, and extends vertically through the center of the sealed container 10.

[0017] The compression mechanism 20 and the electric motor 30 are connected by a rotating shaft 21, which transmits the rotational motion of the electric motor 30 to the compression mechanism 20. In the compression mechanism 20, the transmitted rotational force compresses the refrigerant gas, which is then discharged into the sealed container 10. The sealed container 10 is filled with compressed, high-temperature, high-pressure refrigerant gas, and refrigeration oil is stored below, i.e., at the bottom of, the sealed container 10 to lubricate the compression mechanism 20. An oil pump (not shown) is provided below the rotating shaft 21, and as the rotating shaft 21 rotates, the oil pump draws up refrigeration oil stored at the bottom of the sealed container 10 and supplies it to each sliding part of the compression mechanism 20. This ensures mechanical lubrication of the compression mechanism 20.

[0018] Examples of refrigerants compressed by the hermetic compressor 100 include a single refrigerant selected from R1234yf, R1234ze, R32, and R290, a mixed refrigerant of two or more of these, a mixed refrigerant of any of these with another refrigerant, a mixed refrigerant containing R1132(E), and a mixed refrigerant containing R1123. Further examples include mixed refrigerants of R516A, R445A, R444A, R454C, R444B, R454A, R455A, R457A, R459B, R452B, R454B, R447B, R447A, R446A, and R459A.

[0019] The rotating shaft 21 is composed of a main shaft portion 21a, an eccentric shaft portion 21b, and a counter shaft portion 21c, which are formed in this order from top to bottom in the axial direction. An electric motor 30 is fixed to the main shaft portion 21a by shrink fitting or press fitting, and a cylindrical rolling piston 22 is slidably fitted into the eccentric shaft portion 21b.

[0020] The compression mechanism 20 compresses low-pressure refrigerant gas drawn into the sealed container 10 into high-pressure refrigerant gas using the rotational driving force supplied from the electric motor 30, and discharges the compressed high-pressure refrigerant gas above the compression mechanism 20. As shown in FIGS. 1 and 2 , the compression mechanism 20 is composed of a rolling piston 22, a cylinder 23, an upper bearing 24, a lower bearing 25, and a vane 26. The cylinder 23 has a cylindrical space, i.e., a cylinder chamber 23a, which is open at both axial ends. The cylinder chamber 23a contains an eccentric shaft portion 21b of the rotary shaft 21 that performs eccentric motion within the cylinder chamber 23a, a rolling piston 22 fitted to the eccentric shaft portion 21b, and a vane 26 that partitions the space formed by the inner periphery of the cylinder chamber 23a and the outer periphery of the rolling piston 22.

[0021] The cylinder 23 is formed with a vane groove 23c, one end of which opens into the cylinder chamber 23a and the other end of which is provided with a back pressure chamber 23b. The vane groove 23c houses a vane 26 that reciprocates radially within the vane groove 23c. The vane 26 has a generally rectangular parallelepiped shape, with its circumferential thickness in the cylinder chamber 23a being smaller than its radial and axial lengths when attached to the vane groove 23c. A vane spring (not shown) is provided in the back pressure chamber 23b of the vane groove 23c. Normally, high-pressure refrigerant gas in the sealed container 10 flows into the back pressure chamber 23b, and the pressure difference between the refrigerant gas pressure in the back pressure chamber 23b and the refrigerant gas pressure in the cylinder chamber 23a generates a force that moves the vane 26 radially toward the center of the cylinder chamber 23a. The vane 26 is moved radially toward the center of the cylinder chamber 23a by the force due to the pressure difference between the back pressure chamber 23b and the cylinder chamber 23a and the radial pressing force of the vane spring. The force moving the vane 26 radially causes one end of the vane 26, i.e., the end on the cylinder chamber 23a side, to abut against the cylindrical outer periphery of the rolling piston 22. This separates the space formed by the inner periphery of the cylinder 23 and the outer periphery of the rolling piston 22. Note that even if the pressure difference between the refrigerant gas in the sealed container 10, i.e., the refrigerant gas in the back pressure chamber 23b, and the refrigerant gas in the cylinder chamber 23a, is not sufficient to press the vane 26 against the outer periphery of the rolling piston 22, the force of the vane spring can still press one end of the vane 26 against the outer periphery of the rolling piston 22. Therefore, one end of the vane 26 can always abut against the outer periphery of the rolling piston 22.

[0022] As shown in FIG. 1 , the upper bearing 24 is fitted onto the main shaft portion 21 a of the rotary shaft 21 to rotatably support the main shaft portion 21 a and closes one axial opening of the cylinder chamber 23 a. Similarly, the lower bearing 25 is fitted onto the counter shaft portion 21 c of the rotary shaft 21 to rotatably support the counter shaft portion 21 c and closes the other axial opening of the cylinder chamber 23 a. The cylinder 23 is provided with a suction port (not shown) that draws refrigerant gas into the cylinder chamber 23 a from outside the sealed container 10, and the upper bearing 24 is provided with a discharge port (not shown) that discharges compressed refrigerant gas out of the cylinder chamber 23 a. The upper bearing 24 is substantially inverted T-shaped when viewed from the front, and the lower bearing 25 is substantially T-shaped when viewed from the front.

[0023] A discharge valve (not shown) is provided in the discharge port of the upper bearing 24, and controls the discharge timing of the high-temperature, high-pressure refrigerant gas discharged through the discharge port from the cylinder 23. That is, the discharge valve closes until the refrigerant gas compressed in the cylinder chamber 23a of the cylinder 23 reaches a predetermined pressure, and opens when the pressure reaches or exceeds the predetermined pressure, thereby discharging the high-temperature, high-pressure refrigerant gas out of the cylinder chamber 23a.

[0024] Because the cylinder chamber 23a repeatedly undergoes suction, compression, and discharge operations, the refrigerant gas discharged from the discharge port is discharged intermittently, resulting in noise such as pulsation. To reduce this, a discharge muffler 27 is attached to the outer side of the upper bearing 24, i.e., on the motor 30 side, so as to cover the upper bearing 24. The discharge muffler 27 has a discharge hole (not shown) that connects the space formed by the discharge muffler 27 and the upper bearing 24 to the inside of the sealed container 10. The refrigerant gas discharged from the cylinder 23 through the discharge port is first discharged into the space formed by the discharge muffler 27 and the upper bearing 24, and then discharged from the discharge hole into the sealed container 10.

[0025] A suction muffler 101 is provided on the side of the sealed container 10 to prevent liquid refrigerant from being directly drawn into the cylinder chamber 23a of the cylinder 23. The suction muffler 101 is fixed to the side of the sealed container 10 by welding or other means. Generally, a mixture of low-pressure refrigerant gas and liquid refrigerant is delivered to the hermetic compressor 100 from an external refrigerant circuit connected to the hermetic compressor. However, if liquid refrigerant flows into the cylinder 23 and is compressed by the compression mechanism 20, the compression mechanism 20 will malfunction. Therefore, the suction muffler 101 separates the liquid refrigerant from the refrigerant gas and delivers only the refrigerant gas to the cylinder chamber 23a. The suction muffler 101 is connected to a suction port (not shown) of the cylinder 23 via a suction connecting pipe 70, and the low-pressure refrigerant gas delivered from the suction muffler 101 is drawn into the cylinder chamber 23a via the suction connecting pipe 70.

[0026] The compression mechanism 20 is configured as described above. Rotation of the rotary shaft 21 rotates the eccentric shaft portion 21b of the rotary shaft 21 within the cylinder chamber 23a of the cylinder 23. The volume of the working chamber, defined by the inner periphery of the cylinder chamber 23a, the outer periphery of the rolling piston 22 fitted to the eccentric shaft portion 21b, and the vane 26, increases or decreases as the rotary shaft 21 rotates. First, the working chamber communicates with the suction port, and low-pressure refrigerant gas is drawn in. Next, the communication between the working chamber and the suction port is closed, and the volume of the working chamber decreases, compressing the refrigerant gas within the working chamber. Finally, the working chamber communicates with the discharge port. After the refrigerant gas within the working chamber reaches a predetermined pressure, a discharge valve provided in the discharge port opens, and the compressed, high-pressure, high-temperature refrigerant gas is discharged from the working chamber, i.e., the cylinder chamber 23a.

[0027] The high-pressure, high-temperature refrigerant gas discharged from the cylinder chamber 23a into the sealed container 10 via the discharge muffler 27 passes through the motor 30, rises inside the sealed container 10, and is discharged to the outside of the sealed container 10 from a discharge pipe 102 provided at the top of the sealed container 10. A refrigerant circuit through which the refrigerant flows is configured outside the sealed container 10, and the discharged refrigerant circulates through the refrigerant circuit and returns to the suction muffler 101.

[0028] FIG. 3 is a schematic diagram of a refrigeration cycle apparatus 200 including a hermetic compressor 100 according to the first embodiment. Next, the refrigeration cycle apparatus 200 including the hermetic compressor 100 will be described with reference to FIG. The refrigeration cycle apparatus 200 is, for example, an air conditioner. The refrigeration cycle apparatus 200 includes the hermetic compressor 100 having an intake muffler 101 connected to the intake side of the hermetic compressor 100, a flow path switching valve 103 connected to the discharge side of the hermetic compressor 100, an outdoor heat exchanger 104, a pressure reducer 105, and an indoor heat exchanger 106, which are connected in sequence via piping to form a refrigerant circuit through which a refrigerant circulates. In general, in the refrigeration cycle apparatus 200, the indoor heat exchanger 106 is installed in an indoor unit, and the remaining hermetic compressor 100, the flow path switching valve 103, the outdoor heat exchanger 104, and the pressure reducer 105 are installed in an outdoor unit.

[0029] The flow path switching valve 103 is, for example, a four-way valve that switches the refrigerant flow direction to switch between cooling and heating operation. Note that the flow path switching valve 103 may be a combination of a two-way valve and a three-way valve instead of a four-way valve. The pressure reducer 105 reduces the pressure of the refrigerant to expand it. The pressure reducer 105 is, for example, an electronic expansion valve with an adjustable throttle opening. By adjusting the throttle opening, the pressure of the refrigerant flowing into the indoor heat exchanger 106 during cooling operation and the pressure of the refrigerant flowing into the outdoor heat exchanger 104 during heating operation is controlled. The outdoor heat exchanger 104 functions as an evaporator or condenser, exchanging heat between the air and the refrigerant to evaporate and gasify the refrigerant or condensing and liquefying the refrigerant. The outdoor heat exchanger 104 functions as an evaporator during heating operation and as a condenser during cooling operation. The indoor heat exchanger 106 functions as an evaporator or a condenser, and exchanges heat between the air and the refrigerant to evaporate and gasify the refrigerant or condense and liquefy the refrigerant. The indoor heat exchanger 106 functions as a condenser during heating operation and as an evaporator during cooling operation.

[0030] In heating operation, the flow path switching valve 103 is connected to the solid line side in Figure 3. The high-temperature, high-pressure refrigerant compressed by the hermetic compressor 100 flows to the indoor heat exchanger 106, condenses, and liquefies, and is then throttled by the pressure reducer 105 to become a two-phase refrigerant with low temperature and low pressure. The refrigerant then flows to the outdoor heat exchanger 104, evaporates, and gasifies before passing through the flow path switching valve 103 and returning to the hermetic compressor 100. That is, the refrigerant circulates as shown by the solid arrows in Figure 3. Through this circulation, the refrigerant exchanges heat with outside air in the outdoor heat exchanger 104, which serves as an evaporator, and the refrigerant sent to the outdoor heat exchanger 104 absorbs heat. The refrigerant that has absorbed heat is then sent to the indoor heat exchanger 106, which serves as a condenser, where it exchanges heat with the indoor air and warms the indoor air.

[0031] In cooling operation, the flow switching valve 103 is connected to the dashed line side in Figure 3. The high-temperature, high-pressure refrigerant compressed by the hermetic compressor 100 flows to the outdoor heat exchanger 104, condenses, and liquefies. The refrigerant is then throttled by the pressure reducer 105 to a low-temperature, low-pressure, two-phase state. The refrigerant then flows to the indoor heat exchanger 106, evaporates, and gasifies. The flow switching valve 103 then returns to the hermetic compressor 100. That is, when the operation mode switches from heating to cooling, the indoor heat exchanger 106 changes from a condenser to an evaporator, and the outdoor heat exchanger 104 changes from an evaporator to a condenser. Thus, the refrigerant circulates as shown by the dashed arrows in Figure 3. Through this circulation, the indoor heat exchanger 106, which functions as an evaporator, exchanges heat with the indoor air, absorbing heat from the indoor air and cooling it. The refrigerant that has absorbed heat is then sent to the outdoor heat exchanger 104, which functions as a condenser, where it exchanges heat with the outdoor air and releases heat to the outdoor air.

[0032] Figure 4 is a schematic cross-sectional view of the electric motor 30, taken along the line A-A' of the hermetic compressor 100 of Figure 1, as viewed from the direction of the arrows. Figure 5 is a schematic longitudinal cross-sectional view of the rotor 31, taken along the line C-O-C' of the electric motor 30, as viewed from the direction of the arrows. Next, the electric motor 30 that transmits rotational force to the compression mechanism 20 will be described with reference to Figures 4 and 5. As shown in Figure 4, the electric motor 30 includes a substantially cylindrical stator 51 fixed to the inner circumferential surface of the hermetic container 10, and a substantially columnar rotor 31 disposed inside the stator 51.

[0033] 4 and 5, the rotor 31 includes a rotor core 32 formed by laminating a plurality of steel plates (thin electromagnetic steel plates). Magnet insertion holes 33 are formed in the axial direction of the rotor core 32, and permanent magnets 34 such as ferrite magnets or rare earth magnets are inserted into the magnet insertion holes 33. The permanent magnets 34 form magnetic poles on the rotor 31. The rotor 31 rotates due to the interaction between the magnetic flux created by the magnetic poles on the rotor 31 and the magnetic flux created by the stator windings 54 of the stator 51.

[0034] A shaft hole 39 through which the rotating shaft 21 passes is provided in the center of the rotor core 32, and a main shaft portion 21a of the rotating shaft 21 is fastened to the shaft hole 39 by shrink fitting or the like. This transmits the rotational motion of the rotor 31 to the rotating shaft 21. Air holes 35 and rivet insertion holes 38 are provided around the shaft hole 39, and high-pressure, high-temperature refrigerant compressed by the compression mechanism 20 below the electric motor 30 passes through the air holes 35. The refrigerant compressed by the compression mechanism 20 also passes through the air gap between the rotor 31 and the stator 51 and the gaps in the stator windings 54 in addition to the air holes 35.

[0035] As shown in Figure 5, mounting members 37 are provided on both axial ends of the rotor core 32 to prevent the permanent magnets 34 from jumping out of the magnet insertion holes 33. These mounting members 37 are fixed by rivets 60 that pass through rivet insertion holes 38 in the rotor core 32 and extend in the axial direction. The mounting members 37 may also be something like a balance weight or an end plate.

[0036] FIG. 6 is a partial cross-sectional schematic diagram of the rotor 31 according to the first embodiment, enlarging the portion of the electric motor 30 viewed from the arrow D in FIG. 4 . Next, the distortion suppression member 40 that suppresses distortion of the rotor core 32 due to the centrifugal force of the permanent magnets 34 will be described with reference to FIGS. 5 and 6 . The rotor core 32 is formed with a cavity 36 and a distortion suppression member arrangement hole 41 that are formed in the axial direction of the rotor core 32 and are positioned radially outward of the permanent magnets 34 relative to the axis of the rotor core 32. A non-magnetic distortion suppression member 40 is inserted into the distortion suppression member arrangement hole 41. Both axial ends of the distortion suppression member 40 are fixed to the mounting member 37. The distortion suppression member 40 is formed in a plate shape that is longer in the radial direction than in the circumferential direction in a plan view and is arranged to abut against the radially inner side surface of the distortion suppression member arrangement hole 41. Of the multiple holes formed radially outward from the permanent magnets 34 of the rotor core 32, the holes into which the strain suppression members 40 are inserted are strain suppression member arrangement holes 41, and the holes into which the strain suppression members 40 are not inserted are hollow portions 36. Note that while only one strain suppression member arrangement hole 41 is formed in Fig. 6, multiple strain suppression member arrangement holes 41 may be formed in the circumferential direction, as long as at least one is formed within the range of the circumferential width of the permanent magnets 34.

[0037] In this way, by arranging the strain suppression member 40 so that it abuts against the radially inner side surface of the strain suppression member arrangement hole 41, the repulsive force of the permanent magnet 34 arranged in the magnet insertion hole 33 against the centrifugal force can be increased. Furthermore, by making the strain suppression member 40 plate-shaped, which is longer in the radial direction than in the circumferential direction in a plan view, the section modulus, that is, the resistance to stress (bending moment) that bends the cross section, is greater than that of a conventional round shape or a shape that is elongated in the circumferential direction, even with the same cross-sectional area, and resistance to distortion can be improved. Therefore, distortion of the rotor core 32 due to the centrifugal force of the permanent magnet 34 can be suppressed more than before.

[0038] As shown in FIG. 6 , the radial length L1 of the strain suppression member 40 is longer than the circumferential length L2 of the strain suppression member arrangement hole 41 .

[0039] Fig. 7 is a partial cross-sectional schematic diagram of a modified example of the rotor 31 according to the first embodiment, enlarging the portion of the electric motor 30 viewed from the arrow D in Fig. 4. As shown in Fig. 7, the radial length L1 of the strain suppression member 40 may be shorter than the circumferential length L2 of the strain suppression member arrangement hole 41.

[0040] However, by configuring the radial length L1 of the distortion suppression member 40 to be longer than the circumferential length L2 of the distortion suppression member arrangement hole 41 as shown in Figure 6, the repulsive force against the centrifugal force of the permanent magnet 34 arranged in the magnet insertion hole 33 can be increased compared to when the radial length L1 of the distortion suppression member 40 is configured to be shorter than the circumferential length L2 of the distortion suppression member arrangement hole 41 as shown in Figure 7, and therefore distortion of the rotor core 32 due to the centrifugal force of the permanent magnet 34 can be further suppressed.

[0041] FIG. 8 is a partial cross-sectional schematic diagram of the rotor 31 according to the first embodiment, enlarging the portion of the rotor 31 viewed from the arrow E in FIG. 5 . As shown in FIG. 8 , mounting members 37 provided at both axial ends of the rotor core 32 are provided with grooves 37a into which the ends of the strain suppression members 40 are inserted. The grooves 37a have a first side surface 37b on the radially outer side and a second side surface 37c on the radially inner side. The first side surface 37b and the second side surface 37c face each other. The first side surface 37b and the second side surface 37c are formed linearly along the axial direction. That is, the grooves 37a are formed in a concave shape. The ends of the strain suppression members 40 are press-fitted between the first side surface 37b and the second side surface 37c. By press-fitting the ends of the strain suppression members 40 into the concave grooves 37a, the strain suppression members 40 can be fixed and movement of the strain suppression members 40 within the strain suppression member placement holes 41 can be suppressed. Furthermore, by forming the first side surface 37b on the radially outer side in a straight line along the axial direction, when centrifugal force is applied to the strain suppression member 40, the end of the strain suppression member 40 abuts against the first side surface 37b in the axial direction, thereby increasing the abutting area compared to when the first side surface 37b is formed in an oblique shape. Therefore, the first side surface 37b can better absorb the centrifugal force of the strain suppression member 40 in the axial direction, and the movement of the strain suppression member 40 inside the strain suppression member arrangement hole 41 can be further suppressed.

[0042] As described above, the rotor 31 according to the first embodiment comprises a rotor core 32 formed by stacking a plurality of steel plates, magnet insertion holes 33 formed in the axial direction of the rotor core 32, permanent magnets 34 arranged in the magnet insertion holes 33, mounting members 37 provided at both axial ends of the rotor core 32 to prevent the permanent magnets 34 from protruding from the magnet insertion holes 33, distortion suppression member arrangement holes 41 formed in the axial direction of the rotor core 32 and arranged radially outward of the permanent magnets 34 with respect to the axis of the rotor core 32, and a non-magnetic distortion suppression member 40 arranged within the distortion suppression member arrangement hole 41 and having both ends fixed to the mounting member 37, the distortion suppression member 40 abutting against the radially inner side surface of the distortion suppression member arrangement hole 41 and being formed in the shape of a plate that is longer in the radial direction than in the circumferential direction when viewed in a plane.

[0043] According to the rotor 31 of the first embodiment, the strain suppression members 40 abut against the radially inner side surfaces of the strain suppression member arrangement holes 41 and are formed as plates that are longer in the radial direction than in the circumferential direction in plan view. By arranging the strain suppression members 40 so that they abut against the radially inner side surfaces of the strain suppression member arrangement holes 41 in this way, the repulsive force of the permanent magnets 34 arranged in the magnet insertion holes 33 against the centrifugal force can be increased. Furthermore, by forming the strain suppression members 40 into plates that are longer in the radial direction than in the circumferential direction in plan view, the section modulus is larger for the same cross-sectional area than a conventional round or circumferentially elongated shape, thereby improving resistance to distortion. Therefore, distortion of the rotor core 32 due to the centrifugal force of the permanent magnets 34 can be more effectively suppressed than in the past.

[0044] In addition, in the rotor 31 according to the first embodiment, the radial length L1 of the strain suppression member 40 is longer than the circumferential length L2 of the strain suppression member arrangement hole 41 in plan view.

[0045] According to the rotor 31 of embodiment 1, by configuring the radial length L1 of the distortion suppression member 40 to be longer than the circumferential length L2 of the distortion suppression member arrangement hole 41, the repulsive force against the centrifugal force of the permanent magnet 34 arranged in the magnet insertion hole 33 can be increased compared to when the radial length L1 of the distortion suppression member 40 is configured to be shorter than the circumferential length L2 of the distortion suppression member arrangement hole 41, and therefore distortion of the rotor core 32 due to the centrifugal force of the permanent magnet 34 can be further suppressed.

[0046] Furthermore, in rotor 31 according to the first embodiment, mounting member 37 is provided with groove 37a into which the end of strain suppression member 40 is inserted.

[0047] According to the rotor 31 of embodiment 1, the end of the strain suppression member 40 can be pressed into the groove portion 37a to fix the strain suppression member 40, thereby suppressing movement of the strain suppression member 40 within the strain suppression member arrangement hole 41.

[0048] Moreover, the electric motor 30 according to the first embodiment includes the rotor 31 described above, and a stator 51 that is disposed on the outer periphery of the rotor 31 and rotates the rotor 31 by magnetic action.

[0049] According to the electric motor 30 of the first embodiment, the same effects as those of the rotor 31 described above can be obtained.

[0050] The hermetic compressor 100 according to the first embodiment includes the electric motor 30, a compression mechanism 20 driven by the electric motor 30 and compressing fluid drawn in from the outside, and a hermetic container 10 housing the electric motor 30 and the compression mechanism 20.

[0051] According to the hermetic compressor 100 of the first embodiment, the same effects as those of the rotor 31 described above can be obtained.

[0052] The refrigeration cycle apparatus 200 according to the first embodiment includes the hermetic compressor 100, the outdoor heat exchanger 104, the pressure reducer 105, and the indoor heat exchanger 106.

[0053] According to the refrigeration cycle apparatus 200 of the first embodiment, the same effects as those of the rotor 31 described above can be obtained.

[0054] Second Embodiment A second embodiment will be described below, but explanations of parts that overlap with those of the first embodiment will be omitted, and parts that are the same as or equivalent to those of the first embodiment will be given the same reference numerals.

[0055] FIG. 9 is a partial cross-sectional schematic diagram of the rotor 31 according to the second embodiment, enlarging the area indicated by the arrow E in FIG. 5 . As shown in FIG. 9 , mounting members 37 provided at both axial ends of the rotor core 32 are provided with grooves 37a into which the ends of the strain suppression members 40 are inserted. The grooves 37a have a first side surface 37b on the radially outer side and a second side surface 37c on the radially inner side. The first side surface 37b and the second side surface 37c face each other. The first side surface 37b is linearly formed along the axial direction, and the second side surface 37c is inclined radially outward (or toward the first side surface 37b) as it moves away from the rotor core 32. In other words, the grooves 37a are tapered. The strain suppression members 40 are press-fit between the first side surface 37b and the second side surface 37c. By press-fitting the end of the strain suppression member 40 into the tapered groove 37a in this way, it is possible to achieve closer adhesion than when the end of the strain suppression member 40 is press-fitted into the concave groove 37a. This allows the strain suppression member 40 to be fixed more firmly, and movement of the strain suppression member 40 inside the strain suppression member arrangement hole 41 to be more effectively suppressed.

[0056] Figure 10 is a partial cross-sectional schematic diagram of a modified example of the rotor 31 according to the second embodiment, enlarging the portion of the rotor 31 viewed from the arrow E in Figure 5. In the above description, the first side surface 37b is formed linearly along the axial direction, and the second side surface 37c is formed in an inclined shape that extends radially outward as it moves away from the rotor core 32. However, this is not limited to this. As shown in Figure 10, the first side surface 37b may be formed in an inclined shape that extends radially inward (or toward the second side surface 37c) as it moves away from the rotor core 32, and the second side surface 37c may be formed linearly along the axial direction. In other words, it is sufficient that one of the first side surface 37b and the second side surface 37c is formed linearly along the axial direction, and the other side surface is formed in an inclined shape that extends toward the one side surface as it moves away from the rotor core 32.

[0057] However, by forming the first side surface 37b on the radially outer side in a straight line along the axial direction, when centrifugal force is applied to the strain suppression member 40, the end of the strain suppression member 40 abuts against the first side surface 37b in the axial direction, thereby increasing the abutting area compared to when the first side surface 37b is formed in an oblique shape. Therefore, the first side surface 37b can better absorb the centrifugal force of the strain suppression member 40 in the axial direction, and the movement of the strain suppression member 40 inside the strain suppression member arrangement hole 41 can be more effectively suppressed.

[0058] As described above, in the rotor 31 according to embodiment 2, the groove portion 37a has a first side surface 37b provided on the radially outer side and a second side surface 37c facing the first side surface 37b and provided on the radially inner side, and one of the first side surface 37b and the second side surface 37c is formed linearly along the axial direction, and the other side surface is formed in an inclined manner so as to approach the one side surface as it moves away from the rotor core 32 in the axial direction.

[0059] According to the rotor 31 of embodiment 2, by pressing the end of the strain suppression member 40 into the tapered groove portion 37a, it is possible to achieve closer adhesion than when the end of the strain suppression member 40 is pressed into the concave groove portion 37a, and therefore the strain suppression member 40 can be fixed more firmly and the movement of the strain suppression member 40 within the strain suppression member arrangement hole 41 can be more effectively suppressed.

[0060] As described above, in the rotor 31 according to embodiment 2, the first side surface 37b is formed linearly along the axial direction, and the second side surface 37c is formed obliquely so as to approach the first side surface 37b as it moves away from the rotor core 32 in the axial direction.

[0061] According to the rotor 31 of the second embodiment, by forming the first side surface 37b on the radially outer side in a straight line along the axial direction, when centrifugal force is applied to the strain suppression member 40, the end of the strain suppression member 40 abuts against the first side surface 37b in the axial direction, thereby increasing the abutting area compared to when the first side surface 37b is formed in an oblique shape. Therefore, the first side surface 37b can better absorb the centrifugal force of the strain suppression member 40 in the axial direction, and the movement of the strain suppression member 40 within the strain suppression member arrangement hole 41 can be further suppressed.

[0062] Third Embodiment Hereinafter, a third embodiment will be described, but explanations of parts that overlap with those of the first and second embodiments will be omitted, and parts that are the same as or equivalent to those of the first and second embodiments will be denoted by the same reference numerals.

[0063] FIG. 11 is a partial cross-sectional schematic diagram of a rotor 31 according to the third embodiment, enlarging the portion of the electric motor 30 shown in FIG. 4 as viewed from the arrow D. As shown in FIG. 11 , the rotor core 32 includes an inner rotor core 32a, which is a member located radially inward of the permanent magnets 34, and an outer rotor core 32b, which is a member located radially outward of the permanent magnets 34. The inner rotor core 32a and the outer rotor core 32b are separate components and are disposed with a radial gap between them. In other words, the rotor core 32 does not include a bridge. Furthermore, the distortion suppression member arrangement hole 41 is formed in the outer rotor core 32b. By disposing the inner rotor core 32a and the outer rotor core 32b with a gap between them, there is no bridge connecting the inner rotor core 32a and the outer rotor core 32b. This reduces magnetic leakage from the bridge and reduces magnetic loss.

[0064] 4, rotor 31 is disposed inside stator 51, and as shown in Fig. 5, rotor core 32, a component of rotor 31, has mounting members 37 provided at both axial ends thereof, and these mounting members 37 pass through rivet insertion holes 38 in rotor core 32 and are fixed by rivets 60 extending in the axial direction. Therefore, even if rotor core 32, a component of rotor 31, is made up of separate inner and outer rotor cores 32a, 32b, inner and outer rotor cores 32a, 32b do not come apart and remain in their predetermined positions.

[0065] As described above, in the rotor 31 according to embodiment 3, the rotor core 32 has an inner rotor core 32a, which is a member on the radially inner side of the permanent magnet 34, and an outer rotor core 32b, which is a member on the radially outer side of the permanent magnet 34 and has a distortion suppression member arrangement hole 41 formed therein, and the inner rotor core 32a and the outer rotor core 32b are each constructed as separate bodies and are arranged with a gap in the radial direction.

[0066] In rotor 31 according to embodiment 3, inner rotor core 32 a and outer rotor core 32 b are arranged with a gap between them, and there is no bridge connecting inner rotor core 32 a and outer rotor core 32 b. This reduces magnetic leakage from the bridge, thereby reducing magnetic loss.

[0067] REFERENCE SIGNS LIST 10 Sealed container, 11 Upper container, 12 Lower container, 20 Compression mechanism section, 21 Rotating shaft, 21a Main shaft section, 21b Eccentric shaft section, 21c Sub-shaft section, 22 Rolling piston, 23 Cylinder, 23a Cylinder chamber, 23b Back pressure chamber, 23c Vane groove, 24 Upper bearing, 25 Lower bearing, 26 Vane, 27 Discharge muffler, 30 Electric motor, 31 Rotor, 32 Rotor core, 32a Inner rotor core, 32b Outer rotor core, 33 Magnet insertion hole, 34 Permanent magnet, 35 Air hole, 36 Cavity, 37 Mounting member, 37a Groove section, 37b First side surface, 37c Second side surface, 38 Rivet insertion hole, 39 Shaft hole, 40 Distortion suppression member, 41 Distortion suppression member arrangement hole, 51 Stator, 54 Stator winding, 60 Rivet, 70 Suction connecting pipe, 100 Hermetic compressor, 101 Suction muffler, 102 Discharge pipe, 103 Flow path switching valve, 104 Outdoor heat exchanger, 105 Pressure reducer, 106 Indoor heat exchanger, 200 Refrigeration cycle device.

Claims

1. A rotor core formed by laminating a plurality of steel plates, Magnet insertion holes formed in the axial direction of the rotor core, Permanent magnets arranged in the magnet insertion holes, Mounting members provided at both ends in the axial direction of the rotor core to prevent the permanent magnets from protruding from the magnet insertion holes, Distortion suppression member arrangement holes formed in the axial direction of the rotor core and arranged radially outward of the permanent magnet with respect to the axis of the rotor core, A non-magnetic distortion suppression member arranged in the distortion suppression member arrangement holes and fixed at both ends to the mounting members, The distortion suppression member is In contact with the radially inner side surface of the distortion suppression member arrangement hole and formed in a plate shape that is longer in the radial direction than in the circumferential direction in plan view, In plan view, The radial length of the distortion suppression member is longer than the circumferential length of the distortion suppression member arrangement hole Rotor.

2. The mounting member is provided with a groove portion into which an end portion of the distortion suppression member is inserted The rotor according to claim 1.

3. The groove portion is A first side surface provided on the radially outer side, A second side surface facing the first side surface and provided on the radially inner side, and Of the first side surface and the second side surface, one side surface is formed linearly along the axial direction, and the other side surface is formed obliquely so as to approach the one side surface as it moves away from the rotor core in the axial direction The rotor according to claim 2.

4. The first side surface is formed linearly along the axial direction, and the second side surface is formed obliquely so as to approach the first side surface as it moves away from the rotor core in the axial direction The rotor according to claim 3.

5. The rotor core is An inner side rotor core which is a member on the radially inner side of the permanent magnet, and an outer side rotor core in which the distortion suppression member arrangement hole is formed and which is a member on the radially outer side of the permanent magnet, The inner side rotor core and the outer side rotor core are each formed as separate bodies and arranged with a gap in the radial direction The rotor according to any one of claims 1 to 4.

6. The rotor according to any one of claims 1 to 4, and A stator arranged on the outer circumference of the rotor and rotating the rotor by magnetic action, Electric motor.

7. The electric motor according to claim 6, and A compression mechanism that is driven by the electric motor and compresses fluid sucked from the outside, A hermetic compressor comprising a hermetic container for housing the electric motor and the compression mechanism. Hermetic compressor.

8. The fluid is a refrigerant, The refrigerant is any one of the single refrigerants R1234yf, R1234ze, R32, R290, or a mixed refrigerant of any two or more of these, or a mixed refrigerant of any of these and another refrigerant, or a mixed refrigerant containing R1132(E), or a mixed refrigerant containing R1123. The hermetic compressor according to claim 7.

9. The hermetic compressor according to claim 7, An outdoor heat exchanger, a decompressor, and an indoor heat exchanger. Refrigeration cycle apparatus.