JP6190094B2 - Permanent magnet embedded rotor - Google Patents

Description

  The present invention relates to a permanent magnet embedded type rotor in which a permanent magnet is inserted into a magnet housing hole of a rotor core, and a permanent magnet embedded type in which balance weights are attached to both ends in the axial direction of the rotor and fixed integrally with a fastening member. It relates to the rotor.

  Conventionally, as a balance adjustment structure of a rotor provided with a permanent magnet, as shown in Patent Document 1 (Japanese Patent Laid-Open No. 2-184232), a rotation shaft hole for inserting a rotation shaft into the center of the rotor core; A balance weight-integrated end plate in which a permanent magnet is placed on the outer periphery of the rotor core parallel to the rotation shaft hole and covered with a protective member, and an end plate and a balance weight are integrally formed by die casting at both ends of the rotor core in the axial direction. In the rotor in which a fastening member is inserted into a through hole that is parallel to the rotation shaft hole and fixed integrally, the ring-shaped convex portion of the outer peripheral portion of the end plate of the balance weight integrated type is drilled, etc. There is a rotor that adjusts the amount of unbalance.

Japanese Patent Laid-Open No. 2-184232

  In a rotor equipped with such a balance weight-integrated end plate, after attaching the balance weight-integrated end plate to the rotor core, the ring-shaped convex part on the outer periphery of the end plate is subjected to ungrinding etc. In order to adjust the amount, machining scraps are generated by drilling after the assembly of the rotor is completed. Further, even if the balance amount to be adjusted is very small, it is necessary to provide a ring-shaped convex portion for adjusting the unbalance amount on the outer peripheral portion of the balance weight integrated end plate. For this reason, the rotor shaft length of the end plate itself becomes longer, and the material cost of the balance weight integrated end plate itself increases.

  Also, as one of the purposes of the balance weight integrated end plate itself, the balance weight integrated end plate is provided at both ends of the rotor core in the axial direction so that the permanent magnet does not protrude from the magnet receiving hole provided in the rotor core. Although the plate is mounted and fixed integrally with the fastening member, it is sufficient that only the opening portion where the magnet housing hole of the rotor core is opened can be closed by the balance weight integrated end plate. It is not necessary to cover the entire surface of both ends in the direction.

  On the other hand, if the entire axial end portions of the rotor core of the magnet housing hole into which the permanent magnet of the rotor core is inserted are covered with a balance weight integrated end plate of magnetic material, the magnet housing hole into which the permanent magnet is inserted Since it is covered with a balance weight-integrated end plate made of a magnetic material so as to straddle the inner side and the outer side, it becomes a passage through which the magnetic flux of the permanent magnet leaks, and the efficiency of the electric motor is reduced.

The invention according to claim 1 is provided in an electric motor mounted on a compressor, a rotation shaft hole into which a rotation shaft is inserted at the center of a rotor axis, a V-shaped apex facing the rotation shaft hole side, and V A rotor core having a V-shape with a letter-shaped opening facing the rotor outer diameter side and having four magnetic poles provided with magnet housing holes into which permanent magnets are inserted in parallel with the rotation shaft hole; and the permanent magnet Are fixed together by fastening members inserted into through holes penetrating in parallel with the rotation shaft hole, so that the end plates attached to both ends of the rotor core in the axial direction are prevented from jumping out of the magnet housing hole. In the embedded permanent magnet rotor, at least one of the end plates attached to both axial end portions of the rotor core is formed of a nonmagnetic material and has a balance function with a biased center of gravity. An integrated end plate, The integrated end plate has a thickness and extends from the outer periphery of the rotor of the magnet housing hole provided in one of the two adjacent magnetic poles of the four magnetic poles to the radially outer side of the magnet housing hole. A notch part cut out from the rotor outer periphery side of the magnet accommodation hole provided on the other of the two adjacent magnetic poles to a radially outer side of the magnet accommodation hole, and the two adjacent magnetic poles, respectively. A notch is formed on the inner side in the radial direction of the magnet accommodation hole provided on the magnet from the rotation shaft hole side to the inner side in the radial direction of each of the magnet accommodation holes, and is provided on one of the two adjacent magnetic poles. A notch portion cut out from the rotor outer periphery side of the magnet accommodation hole to the radially outer side of the magnet accommodation hole, and the magnet accommodation hole from the rotor outer periphery side of the magnet accommodation hole provided on the other of the two adjacent magnetic poles. Notch cut out to the outside in the radial direction The balance function is provided by a notch portion that is notched from the rotating shaft hole side to the radially inner side of each of the magnet housing holes on the radially inner side of the magnet housing hole provided in each of the two adjacent magnetic poles. It is a permanent magnet embedded rotor.

  The embedded permanent magnet type rotor using the balance weight integrated end plate of the present invention can shorten the rotor shaft length of the end plate itself and reduce the material cost. Further, even when the amount of unbalance is very small, since there is no need for a drilling process or the like for adjusting the amount of balance, the amount of unbalance can be easily taken without generating machining waste.

  In addition, even if the balance weight-integrated end plate of magnetic material covers the magnet receiving holes into which the permanent magnets at both axial ends of the rotor core are inserted, the balance weight-integrated end plate is mounted on the rotor core. In the balance weight-integrated end plate, a notch portion cut out along the magnet accommodation hole from the outer periphery side of the rotor of the magnet accommodation hole to the radially outer side of the magnet accommodation hole is provided before mounting the rotor. In addition, the area of the magnetic flux path connecting the inner side and the outer side of the permanent magnet can be reduced, leakage of magnetic flux can be reduced, and reduction in the efficiency of the motor can be prevented.

  Further, a notch portion cut out along the magnet accommodation hole from the outer peripheral side of the magnet accommodation hole into which the permanent magnet is inserted into the rotor core to the radially outer side of the magnet accommodation hole in the balance weight integrated end plate. By providing a notch portion cut out along the magnet accommodation hole from the rotation shaft hole side to the inside in the radial direction of the magnet accommodation hole on the radially inner side of the magnet accommodation hole provided with the The area of the magnetic flux path connecting the inner side and the outer side of the magnet can be further reduced, leakage of magnetic flux can be reduced, and a reduction in the efficiency of the motor can be prevented.

  Further, by using a non-magnetic material as the material of the balance weight integrated end plate, it is possible to more reliably prevent magnetic flux leakage.

The top view seen from the axial direction upper end of the rotor of this embodiment. The top view seen from the axial direction lower end of the rotor of this embodiment. P-0-P 'sectional drawing in FIG.1 and FIG.2. The balance weight integrated type end plate used for this embodiment.

An embodiment of an embedded permanent magnet rotor (hereinafter referred to as “rotor”) of the present invention will be described with reference to the drawings.
FIG. 1 is a view as seen from the axial upper end of the rotor 1 in which the permanent magnet 6 is embedded in the rotor core 2. FIG. 2 is a view as seen from the lower end in the axial direction of the rotor 1.
3 is a cross-sectional view of the rotor shown in FIGS. 1 and 2 taken along the line P-0-P ′.
The rotor 1 shown in FIGS. 1 to 3 is formed by laminating thin electromagnetic steel plates punched by a punching press or the like, and providing uneven cut portions in adjacent electromagnetic steel plates in the axial direction so that the uneven cut portions are entangled with each other. The rotor core 2 is constituted by a well-known auto clamp 10 that is caulked together.
In the present embodiment, eight auto clamps 10 are provided.

  The rotor core 2 in FIGS. 1 to 3 is provided with a rotation shaft hole 4 having the axis center of the rotor core 2 as the rotation center of the rotor 1 and the rotation center as the inner diameter center of the rotor 1.

  The magnet housing hole 7 into which the permanent magnet 6 is inserted, the cooling air hole 8 for cooling the rotor 1, and the permanent magnet 6 are housed in the permanent magnet 6 in parallel with the rotation shaft hole 4 of the rotor core 2. A plurality of through holes 9 for fixing the balance weight integrated end plate 5 for closing both ends of the rotor core 2 with the fastening member 3 so as not to jump out of the hole 7 are provided.

  The balance weight integrated end plate 5 attached to the axial end of the rotor core 2 shown in FIGS. 1 to 3 is permanent from the magnet housing hole 7 opened in the axial direction of the rotor core 2 as described above. The opening of the magnet housing hole 7 is closed so that the magnet 6 does not jump out.

In addition, the rotor 1 of the present embodiment is often used mainly as a rotor of an electric motor mounted in a compressor of an air conditioner or a refrigerator. In this case, a mechanical imbalance generated in a compression mechanism portion of the compressor. In order to adjust the amount, a balance weight is often applied to the end of the rotor 1.
The balance weight integrated end plate 5 of the present embodiment has a balance adjustment function for adjusting the unbalance amount and an opening portion of the magnet accommodation hole 7 so that the permanent magnet 6 does not jump out of the magnet accommodation hole 7. Combined with the function of the end plate to close the door.

  The balance weight-integrated end plate 5 attached to both ends of the rotor core 2 of the rotor 1 of the present embodiment has the same shape except that the attaching direction is reversed 180 degrees up and down. 1 will be described with reference to the upper end in the axial direction, and the description of the view from the lower end in the axial direction in FIG.

  In the rotor 1 of the present embodiment, the outer diameter of the rotor core 2 is formed in a cylindrical shape or a different diameter, and the permanent magnet 6 is formed so that the magnetic poles in the rotor core 2 are adjacent to each other with different polarities. Arranged to form four poles (two pole pairs). The arrangement of the permanent magnet 6 in each magnetic pole is arranged so that the V-shaped apex faces the rotation shaft hole 4 side and the V-shaped opening side faces the rotor outer diameter side with the rotation shaft hole 4 as the center. I am letting. The number of magnetic poles is not limited to this.

  Accordingly, the balance weight integrated end plate 5 of the embodiment shown in FIG. 1 to FIG. 3 has the V-shaped apex facing the rotation shaft hole 4 with the rotation shaft hole 4 as the center, and the V-shaped opening side. It arrange | positions so that the magnet accommodation hole 7 which inserted the permanent magnet 6 may be plugged up so that the rotor outer diameter side may be faced.

  Further, the balance weight integrated end plate 5 shown in FIG. 4 used in FIGS. 1 to 3 is provided with a notch 11 cut out from the radial outer periphery of the balance weight integrated end plate 5. By providing this notch 11, a balance weight function is imparted to the end plate.

  The notch position of the balance weight integrated end plate 5 shown in FIG. 4 used in FIGS. 1 to 3 is provided with the notch 11 so that the permanent magnet 6 does not protrude from the magnet housing hole 7 as described above. Therefore, in a state in which the balance weight integrated end plate 5 is mounted on the rotor core 2 on the balance weight integrated end plate 5, the V-shaped apex around the rotation shaft hole 4 is the rotation shaft hole 4. Of the magnet housing hole 7 facing the side and facing the rotor outer diameter side from the V-shaped opening side, along the magnet housing hole 7 from the radially outer peripheral side of the rotor 1 to the radially outer side of the magnet housing hole 7. The notch portion 11 thus cut out is provided on the end plate 5 with an integrated balance weight.

It should be noted that the closing of the magnet accommodation hole 7 with the balance weight integrated end plate 5 is typically performed so that the permanent magnet 6 does not protrude from the magnet accommodation hole 7, and the entire surface of the magnet accommodation hole 7 is blocked. Alternatively, a part of the permanent magnet 6 may be blocked so that the permanent magnet 6 does not protrude from the magnet housing hole 7 in the axial direction.
Moreover, the balance weight integrated type end plate 5 used for this embodiment may be used for the both ends of the rotor core 2, and may be used for either one of the ends. In this case, an end plate having no balance weight function may be used for the other end.

  In addition, in the embodiment of FIGS. 1 to 4, a notch cut out from the radially outer side of the balance weight integrated end portion 5 on the radially outer side of the magnet housing hole 7 in order to give the end plate a further balance weight function. In addition to the portion 11, on the radially inner side of the magnet housing hole 7 provided with the notched portion 11 notched on the radially outer side of the magnet housing hole 7, from the rotary shaft hole 4 side to the radially inner side of the magnet housing hole 7, A cutout portion 12 cut out along the magnet housing hole 7 is provided. Thereby, the balance weight function of the balance weight integrated end portion 5 is improved.

  Moreover, since the end portion is usually arranged so as to straddle the inner side and the outer side in the radial direction of the magnet receiving hole 7 so that the permanent magnet 6 does not protrude from the magnet receiving hole 7, the inner side and the outer side in the radial direction of the permanent magnet 6 are arranged. It becomes a magnetic flux path to be connected, and magnetic flux leakage occurs. In the present embodiment, a notch portion 11 is provided so as to extend along the magnet housing hole 7 from the radially outer periphery of the balance weight integrated end plate 5 to the radially outer side of the magnet housing hole 7, and further, the magnet housing Since the notch portion 12 is provided so as to extend along the magnet accommodation hole 7 from the rotation shaft hole 4 side of the hole 7 to the inside in the radial direction of the magnet accommodation hole 7. It is possible to reduce the area of the magnetic flux path that straddles the outside, and to prevent the permanent magnet 6 from jumping out of the magnet housing hole 7, of course, it is possible to reduce the leakage magnetic flux and prevent the motor efficiency from being lowered.

Further, when the magnetic flux leakage is further reduced by using such a balance weight integrated end plate 5, it is preferable to use a nonmagnetic material as the material of the balance weight integrated end plate 5.
For example, brass, aluminum, stainless steel, etc. can be used as the nonmagnetic material.
Further, the thickness of the balance weight integrated end plate 5 used in the present embodiment is t0.3 to t2.0, but is not limited thereto. Further, the thicknesses of the balance weight integrated end plates 5 attached to both axial ends of the rotor core 2 of the rotor 1 may not be the same, and the balance weight integrated end plates 5 may be used at both ends of the rotor core 2 or may be used at one end of the rotor core 2.

DESCRIPTION OF SYMBOLS 1 ... Rotor 2 ... Rotor core 3 ... Fastening member 4 ... Rotating shaft hole 5 ... Balance weight integrated end plate 6 ... Permanent magnet 7 ... Magnet accommodation hole 8 ... Air holes 9 ... Through holes 10 ... Auto clamps 11, 12 ... Notches

Claims (1)

Provided in an electric motor mounted on the compressor, a rotation shaft hole into which the rotation shaft is inserted at the center of the rotor, a V-shaped apex face the rotation shaft hole side, and a V-shaped opening side is an outer diameter of the rotor A rotor core having a V-shape facing the side and having four magnetic poles provided with a magnet housing hole in which a permanent magnet is inserted in parallel with the rotation shaft hole, and the permanent magnet from the magnet housing hole to the outside In a permanent magnet embedded rotor in which end plates attached to both axial end portions of the rotor core are fixed integrally with a fastening member inserted through a through hole penetrating in parallel with the rotation shaft hole so as not to protrude. ,
At least one of the end plates attached to both axial end portions of the rotor core is a balance weight integrated end plate formed of a nonmagnetic material and having a balance function with a biased center of gravity,
The balance weight integrated end plate has a plate thickness, and the radial direction of the magnet accommodation hole from the rotor outer peripheral side of the magnet accommodation hole provided in one of the two adjacent magnetic poles of the four poles A notch part notched to the outside, a notch part notched from the outer periphery side of the magnet housing hole provided on the other of the two adjacent magnetic poles to the radially outer side of the magnet housing hole, and the two adjacent parts On the radially inner side of the magnet accommodation hole provided in each of the magnetic poles, a notch is provided that is notched from the rotary shaft hole side to the radially inner side of each of the magnet accommodation holes,
A notch part cut out from a rotor outer peripheral side of the magnet accommodation hole provided in one of the two adjacent magnetic poles to a radially outer side of the magnet accommodation hole, and the magnet accommodation provided in the other of the two adjacent magnetic poles The magnet is accommodated from the rotary shaft hole side on the radially inner side of the magnet accommodating hole provided in each of the two adjacent magnetic poles and the notch portion notched from the rotor outer peripheral side of the hole to the radially outer side of the magnet accommodating hole. A permanent magnet embedded rotor, wherein the balance function is provided by a notch portion that is notched radially inward of each hole.

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