JP2013123551A - Motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce inertia force acting on a rotor and improve magnetic properties with flux leak control.SOLUTION: A rotor 25 has multiple drawing openings 27 extending axially with intervals in the circumferential direction. Hollow tubular members 43 constituted of resin materials are fit in the drawing openings 27. A rotor side clutch member 40 is constituted by making a rotor side clutch plate 41, a rotor side clutch gear tooth unit 42 and the tubular members 43 integral mold mutually.

Description

  The present invention relates to a motor.

  Conventionally, a motor that rotates a washing tub and washing blades is mounted on the washing machine (see, for example, Patent Document 1). Since a washing machine requires a relatively large rotational torque, a large motor is mounted. However, when the motor is increased in size, the inertial force that acts on the rotor during high-speed rotation becomes extremely large. Therefore, in order to reduce the inertial force acting on the rotor, it is conceivable to form a plurality of through holes penetrating in the axial direction of the rotor to reduce the weight of the rotor.

JP 2007-105391 A

  However, when a plurality of holes are formed in the rotor, there is a problem that the magnetic flux from the stator toward the rotor leaks out to the holes. This magnetic flux leakage deteriorates the magnetic characteristics.

  The present invention has been made in view of this point, and an object thereof is to reduce the inertial force acting on the rotor and to improve magnetic characteristics by suppressing magnetic flux leakage.

  The present invention is directed to a motor including a stator and a rotor that is rotationally driven with respect to the stator, and has taken the following solutions.

  That is, according to the first aspect of the present invention, the rotor is formed with a plurality of holes extending in the axial direction at intervals in the circumferential direction, and a hollow cylindrical member made of a resin material is formed in the hole. It is characterized by being fitted.

  In the first invention, the rotor is reduced in weight by forming a plurality of holes in the rotor. Thereby, the inertia force which acts on a rotor can be reduced. Further, by fitting a hollow cylindrical member made of a resin material into the plurality of holes, it is possible to suppress the magnetic flux from the stator toward the rotor from leaking to the holes.

  Specifically, when a plurality of holes are formed in the rotor, there is a problem in that magnetic flux from the stator toward the rotor leaks out to the hole side and the magnetic characteristics are deteriorated.

  On the other hand, in the present invention, since the resin-made cylindrical member is fitted into the punched hole to increase the magnetic resistance in the punched hole, magnetic leakage is suppressed by the tubular member and the magnetic characteristics are improved. be able to. In addition, by using a hollow cylindrical member, it is possible to disperse stress concentration compared to the case where a solid member is used, and thus it is possible to ensure strength. Moreover, if it is a hollow cylindrical member, since the usage-amount of a resin material may be small, manufacturing cost can be reduced.

  A second invention is characterized in that, in the first invention, a clutch member having a plurality of tooth portions and integrally molded with the cylindrical member is provided on one end side in the axial direction of the rotor. It is what.

  In the second invention, a clutch member integrally formed with the cylindrical member is provided on one end side in the axial direction of the rotor. Specifically, when this motor is mounted on a washing machine, it is necessary to provide a clutch mechanism for switching between a washing process in which only the pulsator is rotated and a dehydration process in which the spin basket and the pulsator are simultaneously rotated. Therefore, if the clutch member is formed integrally with the cylindrical member, there is no need for a fastening bolt for attaching the clutch member to the rotor, the number of parts and the installation cost can be reduced, and the clutch mechanism can be downsized. Can do.

  A third invention is characterized in that, in the first or second invention, the axial length of the cylindrical member is at least half of the axial length of the rotor.

  In the third aspect of the invention, the tubular member is fitted to a length of half or more of the axial length of the rotor, so that the tubular member does not come out of the punch hole and is long enough to suppress magnetic flux leakage. We are trying to ensure this. Furthermore, compared with the case where the cylindrical member is fitted over the entire length of the rotor in the axial direction, the amount of resin material used can be reduced, so that the manufacturing cost can be reduced.

  According to a fourth invention, in any one of the first to third inventions, the cylindrical member is formed in a cylindrical shape.

  In the fourth invention, by forming the cylindrical member in a cylindrical shape, the strength in the radial direction is increased as compared with the case where other shapes such as a trapezoidal shape, a triangular shape, a spoke shape, and a teardrop shape are adopted. Weight reduction can be achieved.

  According to the present invention, it is possible to improve the magnetic characteristics by fitting a resin-made cylindrical member that is more likely to pass magnetic flux than air into the hole, increasing the effective area through which the magnetic flux flows by the cylindrical member, and suppressing magnetic flux leakage. it can. In addition, by using a hollow cylindrical member, it is possible to disperse stress concentration compared to the case where a solid member is used, and thus it is possible to ensure strength. Moreover, if it is a hollow cylindrical member, since the usage-amount of a resin material may be small, manufacturing cost can be reduced.

It is side surface sectional drawing which shows the structure of the washing machine provided with the motor which concerns on Embodiment 1 of this invention. It is AA arrow sectional drawing of FIG. It is BB arrow sectional drawing of FIG. It is a graph which shows the relationship between the rotation speed of a motor, and a torque. It is a top view which shows the structure of the rotor which concerns on this Embodiment 2. FIG. It is a top view which shows the structure of the rotor which concerns on other embodiment. It is a top view which shows the structure of the rotor which concerns on other embodiment. It is a top view which shows the structure of the rotor which concerns on other embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. It should be noted that the following description of the preferred embodiment is merely illustrative in nature and is not intended to limit the present invention, its application, or its use.

Embodiment 1
FIG. 1 is a side sectional view showing a configuration of a washing machine including a motor according to Embodiment 1 of the present invention. As shown in FIG. 1, the washing machine 10 includes an outer casing 11, an outtab 12 that is elastically suspended and supported in the outer casing 11, and a spin basket 13 that is rotatably accommodated in the outtab 12. Yes.

  The outer casing 11 is formed in a substantially rectangular tube shape. Moreover, the out tab 12 in which the washing water is accommodated and the spin basket 13 in which the laundry is accommodated are each formed in a cylindrical shape.

  The spin basket 13 is loaded with laundry from outside. A pulsator 14 is provided at the bottom of the spin basket 13. The pulsator 14 generates a rotating water flow for washing, and is connected to the rotating shaft 28 of the motor 20. The wall surface of the spin basket 13 is provided with a plurality of through holes (not shown) for sharing the washing water with the out tab 12.

  A motor 20 is disposed below the out tab 12. The motor 20 selectively rotates the spin basket 13 and the pulsator 14 in forward and reverse directions according to a program of a control device (not shown). As a result, the laundry stored in the spin basket 13 is sequentially subjected to washing, rinsing, and dewatering steps.

  Here, whether the spin basket 13 and the pulsator 14 are rotated simultaneously by the motor 20 or only the pulsator 14 is rotated is selectively switched by the clutch mechanism 30. The clutch mechanism 30 includes a basket side clutch member 31 provided on the spin basket 13 side and a rotor side clutch member 40 provided on the motor 20 side.

  The basket-side clutch member 31 includes a basket-side clutch plate 32 having a through-hole 32a formed at the center, a cylindrical cylindrical shaft 33 protruding upward from the center of the basket-side clutch plate 32, and a switching device 36. I have. The rotor side clutch member 40 is provided on the upper portion of the rotor 25 of the motor 20 and has a rotor side clutch tooth portion 42. Details of the rotor side clutch member 40 will be described later.

  The rotating shaft 28 of the rotor 25 passes through the central portion of the basket side clutch plate 32 and is inserted into the inner peripheral side of the cylindrical shaft 33. The rotating shaft 28 is rotatable on the inner peripheral side of the cylindrical shaft 33.

  The upper part of the cylindrical shaft 33 is attached to the bottom part of the spin basket 13. A bearing 34 is provided between the cylindrical shaft 33 and the bottom of the out tab 12. The cylindrical shaft 33 is rotatably supported by a bearing 34.

  The switching device 36 is provided on the lower surface side of the out tab 12. The switching device 36 is configured to move the basket-side clutch plate 32 upward when turned on by a control device (not shown) inside the washing machine 10.

  A plurality of basket-side clutch teeth 35 that are engaged with the rotor-side clutch teeth 42 are provided on the lower surface side of the basket-side clutch plate 32. Here, in the state where the basket side clutch plate 32 is pulled up by the switching device 36, the basket side clutch tooth portion 35 does not engage with the rotor side clutch tooth portion 42, so that only the pulsator 14 rotates. On the other hand, in the state where the basket side clutch plate 32 is lowered, the basket side clutch tooth portion 35 engages with the rotor side clutch tooth portion 42, and the spin basket 13 and the pulsator 14 rotate simultaneously.

  2 is a cross-sectional view taken along the line AA in FIG. 1, and FIG. 3 is a cross-sectional view taken along the line BB. As shown in FIGS. 2 and 3, the motor 20 includes a ring-shaped stator 21 and a rotor 25 that is rotatably disposed inside the stator 21.

  The stator 21 is formed in a cylindrical shape in which electromagnetic steel plates formed in an annular shape are stacked. On the inner peripheral side of the stator 21, a plurality of teeth 22 that protrude inward in the radial direction and extend in the axial direction are provided at intervals in the circumferential direction. A coil 23 for generating a rotating magnetic field is wound around the tooth 22.

  The rotor 25 is configured by laminating electromagnetic steel plates. A plurality of salient poles 26 are provided on the outer peripheral surface of the rotor 25 so as to protrude radially outwardly with an interval in the circumferential direction and extend in the axial direction. The salient poles 26 are opposed to the teeth 22 of the stator 21 with a predetermined gap. A shaft hole 25 a is formed in the shaft center of the rotor 25. A rotary shaft 28 is fitted in the shaft hole 25a. The rotor 25 rotates in the stator 21 together with the rotation shaft 28.

  A rotor side clutch member 40 is provided on the upper portion of the rotor 25. The rotor-side clutch member 40 includes a disc-shaped rotor-side clutch plate 41, a plurality of rotor-side clutch tooth portions 42 that protrude radially on the upper surface side of the rotor-side clutch plate 41, and a lower surface of the rotor-side clutch plate 41. And a plurality of cylindrical members 43 provided on the side. The rotor-side clutch plate 41, the rotor-side clutch tooth portion 42, and the cylindrical member 43 are made of a resin material that is integrally molded with each other. As the resin material, for example, polypropylene is used.

  In the rotor 25, a plurality of punch holes 27 are formed at intervals in the circumferential direction. Specifically, the punch hole 27 is located on the center line connecting the salient pole 26 and the shaft hole 25a, and is formed in a trapezoidal shape having a short side on the shaft hole 25a side and a long side on the salient pole 26 side. The hole 27 is for reducing the weight of the rotor 25, and as a result, the inertial force acting on the rotor 25 can be reduced.

  A cylindrical member 43 of the rotor side clutch member 40 is fitted into the punch hole 27. The cylindrical member 43 is fitted into the punch hole 27 by press-fitting. Note that an adhesive agent or the like may be applied to the outer peripheral surface of the cylindrical member 43 so as to be fitted into the hole 27.

  FIG. 4 is a graph showing the relationship between the rotational speed of the motor and the torque. As shown in FIG. 4, the motor 20 according to this embodiment in which a hollow cylindrical member 43 made of a resin material is fitted into the plurality of holes 27 is fitted with the cylindrical member 43. It can be seen that the motor torque is higher than that of the conventional motor without the motor.

  Thus, by fitting the hollow cylindrical member 43 made of a resin material into the plurality of extraction holes 27, the magnetic path in the extraction hole 27 is expanded, and the magnetic flux from the stator 21 toward the rotor 25 is extracted. Leakage to the hole 27 side can be suppressed and magnetic characteristics can be improved. Moreover, since the stress concentration can be dispersed by using the hollow cylindrical member 43 as compared with the case where the solid member is used, the strength can be ensured. In addition, if the hollow cylindrical member 43 is used, the amount of resin material used can be reduced, so that the manufacturing cost can be reduced.

  Further, since the rotor-side clutch plate 41, the rotor-side clutch tooth portion 42, and the tubular member 43 constituting the rotor-side clutch member 40 are integrally formed with each other, the fastening for attaching the rotor-side clutch member 40 to the rotor 25 is performed. Bolts and the like are no longer necessary, and the number of parts and mounting costs can be reduced, and the clutch mechanism 30 can be downsized.

  The motor 20 having such a configuration is generally called a switched reluctance motor. In the motor 20, a magnetic attractive force is generated between the teeth 22 of the stator 21 and the salient poles 26 of the rotor 25 by energizing the coil 23 of the stator 21. Due to this magnetic attraction force, torque acts in a direction in which the salient poles 26 of the rotor 25 face the teeth 22 of the stator 21, thereby rotating the rotor 25. The rotor 25 is continuously rotated by switching the energization states of the plurality of coils 23.

−Clutch mechanism switching operation−
Next, the switching operation of the clutch mechanism 30 in the washing machine 10 will be described with reference to FIG. When the spin basket 13 and the pulsator 14 are rotated simultaneously, the switching device 36 places the basket-side clutch plate 32 on the rotor 25 as indicated by the phantom line in FIG. Thereby, the basket side clutch tooth part 35 and the rotor side clutch tooth part 42 engage. When the motor 20 is rotated in this state, the rotating shaft 28 rotates, the basket side clutch plate 32 also rotates, and the cylindrical shaft 33 also rotates. As a result, the spin basket 13 and the pulsator 14 rotate simultaneously.

  On the other hand, when only the pulsator 14 is rotated, the switching device 36 moves the basket side clutch plate 32 upward, as shown by a solid line in FIG. 1, and the basket side clutch tooth portion 35 and the rotor side clutch tooth portion 42. And disconnect. As a result, only the rotor 25 rotates and the basket side clutch plate 32 does not rotate. That is, when the rotating shaft 28 rotates, only the pulsator 14 rotates.

<< Embodiment 2 >>
FIG. 5 is a plan view showing the configuration of the rotor according to the second embodiment. Since the difference from the first embodiment is only the shape of the punch hole 27, the same parts as those of the first embodiment are denoted by the same reference numerals, and only the differences will be described.

  As shown in FIG. 5, the rotor 25 is formed with a plurality of holes 27 at intervals in the circumferential direction. Specifically, the hole 27 is located on the center line connecting the salient pole 26 and the shaft hole 25a, and is formed in a cylindrical shape. A cylindrical member 43 of the rotor side clutch member 40 is fitted into the punch hole 27. The cylindrical member 43 is formed in a cylindrical shape, and is fitted into the hole 27 by press-fitting.

  Thus, by forming the cylindrical member 43 in a cylindrical shape, the strength in the radial direction is increased and the weight is reduced as compared with the case where other shapes such as a trapezoidal shape, a triangular shape, a spoke shape, and a teardrop shape are adopted. Can be achieved.

<< Other Embodiments >>
About the said embodiment, it is good also as following structures.

  In the present embodiment, the axial length of the cylindrical member 43 is substantially the same as the axial length of the rotor 25, but is not limited to this configuration. For example, the axial length of the cylindrical member 43 only needs to be at least half the axial length of the rotor 25.

  As described above, the cylindrical member 43 is fitted to a length of half or more of the axial length of the rotor 25, so that the cylindrical member 43 does not come out of the punch hole 27 and is sufficient to suppress magnetic flux leakage. Long length can be secured. Furthermore, compared to the case where the cylindrical member 43 is fitted over the entire length of the rotor 25 in the axial direction, the amount of resin material used can be reduced, so that the manufacturing cost can be reduced.

  Moreover, although this embodiment demonstrated the case where the shape of the cylindrical member 43 was made trapezoidal or cylindrical, it is not limited to this form. For example, the cylindrical member 43 may have a triangular shape, a spoke shape, or a teardrop shape.

  Moreover, although this embodiment demonstrated the case where the motor 20 was used for the washing machine 10, the motor 20 which concerns on this embodiment is applicable also to the other apparatus which needs a clutch operation. Moreover, arrangement | positioning, the number, shape, etc. of the basket side clutch tooth part 35 and the rotor side clutch tooth part 42 are an example to the last, and are not limited to this form. That is, any form may be used as long as the basket side clutch plate 32 and the rotor side clutch tooth portion 42 can be engaged and rotated.

  Moreover, although this embodiment demonstrated the form using the switched reluctance motor as the motor 20, it is not limited to this form. For example, as shown in FIGS. 6 to 8, an IPM (Interior Permanent Magnet) type brushless DC motor in which permanent magnets 46 are embedded in a plurality of flux barriers 45 formed at intervals in the circumferential direction of the rotor 25 is used. It can also be applied to. Further, the present invention can be similarly applied to an SPM (Surface Permanent Magnet) type motor in which a permanent magnet is disposed on the outer peripheral surface of the rotor 25.

  In FIG. 6, the flux barrier 45 has a rectangular fitting opening 45 a and inclined openings 45 b extending obliquely outward from both ends of the fitting opening 45 a. A plate-like permanent magnet 27 is fitted in the fitting opening 45a. On the center line connecting the intermediate position of the flux barriers 45 adjacent to each other and the shaft hole 25a, a punch hole 27 is formed. The hole 27 is formed in a trapezoidal shape having a long side on the shaft hole 25a side and a short side on the outer peripheral side. A cylindrical member 43 is fitted in the punch hole 27.

  In FIG. 7, the flux barrier 45 has a pair of fitting openings 45 a that are each formed in a rectangular shape and are arranged in a V shape at an obtuse angle. A plate-like permanent magnet 27 is fitted in the fitting opening 45a. On the center line connecting the intermediate position of the flux barriers 45 adjacent to each other and the shaft hole 25a, a punch hole 27 is formed. The hole 27 is formed in a trapezoidal shape having a long side on the shaft hole 25a side and a short side on the outer peripheral side. A cylindrical member 43 is fitted in the punch hole 27.

  In FIG. 8, the flux barrier 45 is formed by a curved fitting opening 45a. A curved plate-like permanent magnet 27 is fitted in the fitting opening 45a. Cylindrical punch holes 27 are formed on the center lines connecting the intermediate positions of the flux barriers 45 adjacent to each other and the shaft holes 25a. A cylindrical member 43 is fitted in the punch hole 27.

  In addition, arrangement | positioning, the number, shape, etc. of the punch hole 27 and the cylindrical member 43 are an example to the last, and are not limited to this form.

  As described above, the present invention reduces the inertial force that acts on the rotor, and suppresses magnetic flux leakage, thereby improving the magnetic characteristics. The above availability is high.

20 Motor 21 Stator 25 Rotor 27 Punching hole 40 Rotor side clutch member 42 Rotor side clutch tooth part 43 Cylindrical member

Claims (4)

A motor comprising a stator and a rotor that is driven to rotate with respect to the stator,
The rotor is formed with a plurality of punched holes extending in the axial direction at intervals in the circumferential direction,
A motor characterized in that a hollow cylindrical member made of a resin material is fitted into the punched hole. In claim 1,
A motor having a plurality of teeth and a clutch member integrally formed with the cylindrical member is provided on one end side in the axial direction of the rotor. In claim 1 or 2,
The axial length of the tubular member is at least half the axial length of the rotor. In any one of claims 1 to 3,
The cylindrical member is formed in a cylindrical shape.

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