JP2020145775A - Rotary electric machine - Google Patents

Abstract

To obtain a rotary electric machine capable of reducing a housing size in a radial direction.SOLUTION: The rotary electric machine comprises a housing 2; a stator core 31 having a plurality of annularly arranged split cores 311 and overlapped onto the housing 2; a stator holder 32 for fixing the plurality of split cores 311, that is provided around the stator core 31; and a plurality of pins 33 for fixing the stator core 31 to the housing 2, that is provided over the housing 2 and the stator core 31. A plurality of fixing holes 314 where the plurality of pins 33 are inserted are formed in the stator core 31.SELECTED DRAWING: Figure 5

Description

The present invention relates to a rotary electric machine having a stator core having a plurality of split cores.

Conventionally, a rotary electric machine having a housing, a stator holder fixed to the housing, and a stator core having a plurality of divided cores and held by the stator holder is known. The plurality of divided cores are arranged side by side in an annular shape. The stator holder has a cylindrical portion provided around the stator core and fixing the plurality of divided cores to each other, and a flange portion extending radially outward from the cylindrical portion and fixed to the housing (for example). , Patent Document 1).

Japanese Unexamined Patent Publication No. 2014-193083

However, the housing is axially overlapped with the flange portion. As a result, there is a problem that the size of the housing in the radial direction becomes large.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a rotary electric machine capable of reducing the size of a housing in the radial direction.

The rotary electric machine according to the present invention has a housing and a plurality of divided cores arranged in an annular shape, and is provided over the stator core stacked on the housing and the housing and the stator core to fix the stator core to the housing. It has multiple pins to do.

According to the rotary electric machine according to the present invention, the size of the housing in the radial direction can be reduced.

It is a vertical sectional view which shows the rotary electric machine which concerns on Embodiment 1 of this invention. It is a perspective view which shows the stator and the rotor of FIG. It is a perspective view which shows the stator holder of FIG. It is a perspective view which shows the modification of the stator holder of FIG. It is an exploded perspective view which shows the rotary electric machine of FIG. It is a top view which shows the split core of FIG. It is a top view which shows the modification of the division core of FIG. It is a top view which shows the modification of the division core of FIG. It is an exploded perspective view which shows the rotary electric machine which concerns on Embodiment 2 of this invention. It is a top view which shows the division core of FIG. It is a top view which shows the modification of the division core of FIG.

Embodiment 1.
FIG. 1 is a vertical sectional view showing a rotary electric machine according to a first embodiment of the present invention. The rotary electric machine 1 is provided in the housing 2, the stator 3 provided in the housing 2, the rotor 4 provided opposite to the stator 3, the shaft 5 provided in the rotor 4, and the shaft 5 provided in the housing 2. It is provided with a pair of bearings 6 that rotatably support the.

The housing 2 has a first housing portion 21 and a second housing portion 22 provided apart from the first housing portion 21 in the axial direction of the shaft 5. In this example, the axial direction is the axial direction with respect to the shaft 5. The stator 3 is arranged between the first housing portion 21 and the second housing portion 22 in the axial direction.

The rotor 4 is arranged so as to face the stator 3 in the radial direction of the shaft 5. In this example, the radial direction is the radial direction of the shaft 5. The rotor 4 is arranged radially inside the stator 3.

The rotor 4 has a cylindrical rotor core 41 fixed to the shaft 5 and a plurality of permanent magnets 42 provided on the outer peripheral surface of the rotor core 41. The plurality of permanent magnets 42 are arranged side by side at equal intervals in the circumferential direction of the shaft 5. In this example, the circumferential direction is the circumferential direction of the shaft 5. The rotor 4 rotates in the circumferential direction with respect to the stator 3 due to the magnetic flux generated between the stator 3 and the rotor 4.

The stator 3 has a stator core 31, a stator holder 32 provided radially outward of the stator core 31, and a plurality of pins 33 provided across the housing 2 and the stator core 31.

FIG. 2 is a perspective view showing the stator 3 and the rotor 4 of FIG. Note that pin 33 is not shown in FIG. The stator core 31 has a plurality of divided cores 311 provided side by side in an annular shape. The plurality of divided cores 311 are fixed to each other by the stator holder 32. The split core 311 has a back yoke portion 312 and a magnetic pole tooth portion 313 integrally formed with the back yoke portion 312. The magnetic pole tooth portion 313 is formed so as to extend radially inward from the back yoke portion 312.

The stator 3 further has a plurality of coils 34 provided in each of the plurality of magnetic pole teeth portions 313. When a current is supplied to the coil 34, a magnetic flux is generated in the coil 34.

The divided core 311 is formed by laminating a plurality of plate-shaped core pieces in the axial direction. As a result, the iron loss generated in the split core 311 is reduced. The split core 311 has one back yoke portion 312 and one magnetic pole tooth portion 313. In other words, the stator core 31 is divided into a plurality of parts so that one divided core 311 has one magnetic pole tooth portion 313. A plurality of divided cores 311 are manufactured separately by punching a steel plate which is a material of a core piece constituting the divided core 311. As a result, the yield of the steel sheet is improved as compared with the case where the entire stator core 31 is manufactured at the same time by punching the steel sheet.

When the entire stator core 31 is manufactured by punching out a steel plate, a space for a coil winding nozzle for arranging the coil 34 is required between the magnetic pole teeth portions 313 adjacent to each other in the circumferential direction. As a result, there is a problem that the number of turns of the coil 34 is reduced.

On the other hand, when a plurality of divided cores 311 are manufactured separately by punching a steel plate, there is no need for a space for a coil winding nozzle to pass between the magnetic pole teeth portions 313 adjacent to each other in the circumferential direction. As a result, the number of turns of the coil 34 can be increased. Therefore, the efficiency of the rotary electric machine 1 can be improved.

When the roundness of the radial inner portion of the stator core 31 is low, the suction force generated between the stator 3 and the rotor 4 varies when the rotor 4 rotates with respect to the stator 3. As a result, the vibration and sound generated in the rotary electric machine 1 increase. In order to increase the roundness of the radial inner portion of the stator core 31, the plurality of divided cores 311 arranged in an annular shape need to be fixed to each other by using the stator holder 32 having high dimensional accuracy.

FIG. 3 is a perspective view showing the stator holder 32 of FIG. In the stator holder 32, one metal plate constituting the stator holder 32 is curved in a cylindrical shape, both ends in the circumferential direction of one metal plate are butted in the circumferential direction, and both ends in the circumferential direction of one metal plate are abutted. Manufactured by joining together by welding. The welded portion 321 formed on the stator holder 32 is arranged on the same circumference as other portions of the stator holder 32 except the welded portion 321. As a result, the stator holder 32 with high dimensional accuracy can be obtained.

The metal plate constituting the stator holder 32 does not need to be specially processed. As a result, the processing cost of the stator holder 32 can be reduced. Further, it is possible to reduce the number of control items for improving the dimensional accuracy of the stator holder 32.

By improving the dimensional accuracy of the stator holder 32, it is possible to improve the dimensional accuracy of the stator 3 after the stator holder 32 is assembled to the stator core 31. As a result, vibration and sound generated in the rotary electric machine 1 can be suppressed.

FIG. 4 is a perspective view showing a modified example of the stator holder 32 of FIG. In the stator holder 32, one metal plate constituting the stator holder 32 is curved in a cylindrical shape, both ends in the circumferential direction of one metal plate are overlapped in the radial direction, and both ends in the circumferential direction of one metal plate are overlapped. It may be manufactured by joining them together by welding. Even in this case, the metal plate constituting the stator holder 32 does not need to be specially processed. As a result, the processing cost of the stator holder 32 can be reduced. Further, it is possible to reduce the number of control items for improving the dimensional accuracy of the stator holder 32.

Further, even in this case, by improving the dimensional accuracy of the stator holder 32, it is possible to improve the dimensional accuracy of the stator 3 after the stator holder 32 is assembled to the stator core 31. As a result, vibration and sound generated in the rotary electric machine 1 can be suppressed.

Note that both ends of one metal plate in the circumferential direction may be fixed to each other by using, for example, bolts instead of welding.

FIG. 5 is an exploded perspective view showing the rotary electric machine 1 of FIG. The rotor 4 is not shown in FIG. Among the plurality of pins 33, the pin 33 provided across the first housing portion 21 and the stator core 31 is referred to as the first pin 331, and the pin 33 provided across the second housing portion 22 and the stator core 31 is designated as the first pin 331. The second pin is 332.

The first housing portion 21 is formed with a plurality of first fixing holes (not shown) into which the first pin 331 is inserted. The first pin 331 is fixed to the first housing portion 21 by press-fitting the first pin 331 into the first fixing hole formed in the first housing portion 21.

A plurality of second fixing holes 221 into which the second pin 332 is inserted are formed in the second housing portion 22. The second pin 332 is fixed to the second housing portion 22 by press-fitting the second pin 332 into the second fixing hole 221.

A plurality of fixing holes 314 into which the pins 33 are inserted are formed in the back yoke portion 312. The housing 2 and the back yoke portion 312 are fixed to each other by press-fitting the pin 33 into the fixing hole 314.

Specifically, the back yoke portion 312 is formed with a plurality of fixing holes 314 into which the first pin 331 is inserted and a plurality of fixing holes 314 into which the second pin 332 is inserted. The first pin 331 is fixed to the back yoke portion 312 by press-fitting the first pin 331 into the fixing hole 314. As a result, the first housing portion 21 and the back yoke portion 312 are fixed to each other. On the other hand, the second pin 332 is fixed to the back yoke portion 312 by press-fitting the second pin 332 into the fixing hole 314. As a result, the second housing portion 22 and the back yoke portion 312 are fixed to each other.

The number of pins 33 may be any number as long as the first housing portion 21 and the stator core 31 can be fixed and the second housing portion 22 and the stator core 31 can be fixed. Specifically, if the number of pins 33 for fixing the first housing portion 21 and the stator core 31 to each other and the number of pins 33 for fixing the second housing portion 22 and the stator core 31 to each other are two or more. Good.

The housing 2 and the stator core 31 are fixed to each other by using a pin 33 in a state where the housing 2 and the stator core 31 are overlapped with each other in the axial direction. As a result, the dimensions of the housing 2 in the radial direction and the dimensions of the stator core 31 in the radial direction can be matched with each other. Therefore, the size of the housing 2 in the radial direction can be reduced. As a result, the material cost of the housing 2 can be suppressed.

The housing 2 and the stator core 31 are fixed to each other by using a pin 33. The pin 33 receives the slip torque generated in the stator 3 by the suction force generated between the stator 3 and the rotor 4. As a result, the hoop stress generated in the stator holder 32 can be reduced. Therefore, the plate thickness of the stator holder 32 can be reduced. As a result, the moldability of the stator holder 32 can be improved, and the material cost of the stator holder 32 can be suppressed.

By reducing the hoop stress generated in the stator holder 32, the tightening allowance of the stator holder 32 with respect to the stator core 31 can be reduced. As a result, the workability of fitting the stator core 31 to the stator holder 32 can be improved.

FIG. 6 is a plan view showing the split core 311 of FIG. The fixing hole 314 is formed in the central portion in the circumferential direction of the back yoke portion 312. The number of fixing holes 314 formed in one back yoke portion 312 is one. The fixing hole 314 is formed so as to extend in the axial direction. The shape of the fixing hole 314 when viewed in the axial direction is a circular shape.

The pin 33 is a round pin corresponding to the shape of the fixing hole 314. In other words, the shape of the pin 33 is a cylindrical shape corresponding to the shape of the fixing hole 314. The pin 33 is not limited to a round pin, and may be, for example, a diamond pin, a reamer bolt, or the like.

FIG. 7 is a plan view showing a modified example of the split core 311 of FIG. The shape of the fixing hole 314 when viewed in the axial direction may be an elongated hole shape extending in the radial direction. In this case, the number of fixing holes 314 into which the pins 33 are inserted is set to 3 or more in the entire stator core 31. Even in this case, the pin 33 receives the slip torque generated in the stator 3 due to the suction force generated between the stator 3 and the rotor 4. The variation of the split core 311 in the radial direction is suppressed by the hoop stress generated in the stator holder 32.

FIG. 8 is a plan view showing a modified example of the divided core 311 of FIG. The number of fixing holes 314 formed in one back yoke portion 312 may be two. In this case, the two fixing holes 314 are arranged side by side at intervals in the circumferential direction. By press-fitting the pin 33 into each of the two fixing holes 314, it is possible to suppress the occurrence of inclination of the split core 311 with respect to the plane perpendicular to the axial direction, and the radial inner portion of the stator 3. The roundness of can be improved. As a result, the gap between the stator 3 and the rotor 4 can be made uniform in the circumferential direction. Therefore, the suction force generated between the stator 3 and the rotor 4 can be made uniform in the circumferential direction. As a result, the vibration and sound generated in the rotary electric machine 1 can be suppressed. The number of fixing holes 314 formed in one back yoke portion 312 may be one or more.

As described above, according to the rotary electric machine 1 according to the first embodiment of the present invention, a plurality of pins 33 are provided across the housing 2 and the stator core 31 and fix the stator core 31 to the housing 2. ing. As a result, the dimensions of the housing 2 in the radial direction and the dimensions of the stator core 31 in the radial direction can be matched with each other. Therefore, the size of the housing 2 in the radial direction can be reduced. As a result, the material cost of the housing 2 can be suppressed. As a result, the manufacturing cost of the rotary electric machine 1 can be suppressed. Further, by reducing the size of the housing 2 in the radial direction, the size of the rotary electric machine 1 can be reduced.

Further, the stator core 31 is fixed to the housing 2 by a plurality of pins 33. As a result, it is not necessary to form a flange portion on the stator holder 32 for fixing the stator holder 32 to the housing 2. Therefore, the structure of the stator holder 32 can be simplified. As a result, the processing cost of the stator holder 32 can be suppressed. Further, by simplifying the structure of the stator holder 32, the dimensional accuracy of the stator holder 32 and the stator 3 can be improved. Further, by improving the dimensional accuracy of the stator holder 32 and the stator 3, it is possible to suppress the vibration and noise generated in the rotary electric machine 1.

Further, the stator core 31 is formed with a plurality of fixing holes 314 into which a plurality of pins 33 are inserted. Thereby, the stator core 31 can be fixed to the housing 2 with a simple configuration.

Further, the rotary electric machine 1 is provided around the stator core 31 and includes a stator holder 32 for fixing the plurality of divided cores 311 to each other. As a result, the stator core 31 can be fixed to the housing 2 by press-fitting the pin 33 only into the fixing holes 314 formed in at least two of the divided cores 311.

Embodiment 2.
FIG. 9 is an exploded perspective view showing a rotary electric machine according to the second embodiment of the present invention. Each of the plurality of split cores 311 is fixed to the housing 2 using a pin 33. The rotary electric machine 1 does not include the stator holder 32. As a result, the dimensions of the housing 2 in the radial direction and the dimensions of the stator 3 in the radial direction can be matched with each other. Therefore, the housing 2 in the radial direction can be made smaller. As a result, the material cost of the housing 2 can be suppressed.

The housing 2 and the stator 3 are fixed to each other by using a pin 33. As a result, the pin 33 receives the slip torque generated in the stator 3 due to the suction force generated between the stator 3 and the rotor 4.

Each of the plurality of split cores 311 is fixed to the housing 2 using a pin 33. As a result, it is not necessary to hold the split core 311 in an annular shape by the stator holder 32. Therefore, the stator holder 32 can be reduced. As a result, the material cost of the stator holder 32 can be reduced, and the processing cost of the stator holder 32 can be reduced.

FIG. 10 is a plan view showing the split core 311 of FIG. The fixing hole 314 is formed in the central portion in the circumferential direction of the back yoke portion 312. The number of fixing holes 314 formed in one back yoke portion 312 is one. The fixing hole 314 is formed so as to extend in the axial direction. The shape of the fixing hole 314 when viewed in the axial direction is a circular shape.

The pin 33 is a round pin corresponding to the shape of the fixing hole 314. In other words, the shape of the pin 33 is a cylindrical shape corresponding to the shape of the fixing hole 314. The pin 33 is not limited to a round pin, and may be, for example, a diamond pin, a reamer bolt, or the like. Other configurations are the same as those in the first embodiment.

FIG. 11 is a plan view showing a modified example of the divided core 311 of FIG. The number of fixing holes 314 formed in one back yoke portion 312 may be two. In this case, the two fixing holes 314 are arranged side by side at intervals in the circumferential direction. By press-fitting the pin 33 into each of the two fixing holes 314, it is possible to suppress the occurrence of inclination of the split core 311 with respect to the plane perpendicular to the axial direction, and the radial inner portion of the stator 3. The roundness of can be improved. As a result, the gap between the stator 3 and the rotor 4 can be made uniform in the circumferential direction. Therefore, the suction force generated between the stator 3 and the rotor 4 can be made uniform in the circumferential direction. As a result, the vibration and sound generated in the rotary electric machine 1 can be suppressed. The number of fixing holes 314 formed in one back yoke portion 312 may be one or more.

As described above, according to the rotary electric machine 1 according to the second embodiment of the present invention, the plurality of pins 33 are provided over the housing 2 and the plurality of divided cores 311 respectively. As a result, the rotary electric machine 1 does not require the stator holder 32. Therefore, the configuration of the rotary electric machine 1 can be simplified.

In each of the above embodiments, the configuration in which the pin 33 is fixed to the first housing portion 21 by press-fitting the pin 33 into the first fixing hole has been described. However, the pin 33 may be integrally formed with the first housing portion 21. Further, the configuration in which the pin 33 is fixed to the second housing portion 22 by press-fitting the pin 33 into the second fixing hole 221 has been described. However, the pin 33 may be integrally formed with the second housing portion 22.

1 Rotating electric machine, 2 housing, 3 stator, 4 rotor, 5 shaft, 6 bearing, 21 1st housing part, 22 2nd housing part, 31 stator core, 32 stator holder, 33 pins, 34 coil, 41 rotor core, 42 permanent magnet , 221 2nd fixing hole, 311 split core, 312 back yoke part, 313 magnetic pole tooth part, 314 fixing hole, 321 welding part, 331 1st pin, 332 2nd pin.

Claims (4)

With the housing
A stator core having a plurality of divided cores arranged in an annular shape and stacked on the housing,
A rotary electric machine provided across the housing and the stator core and provided with a plurality of pins for fixing the stator core to the housing. The rotary electric machine according to claim 1, wherein a plurality of fixing holes into which the plurality of pins are inserted are formed in the stator core. The rotary electric machine according to claim 1 or 2, further comprising a stator holder provided around the stator core and fixing the plurality of divided cores to each other. The rotary electric machine according to claim 1 or 2, wherein the plurality of pins are provided over the housing and each of the plurality of divided cores.

Images