JP2014018014A - Permanent magnet motor, and method of manufacturing the same - Google Patents

Abstract

[PROBLEMS] To prevent demagnetization of a permanent magnet due to magnet heat generation and a decrease in motor performance, and to realize further miniaturization and higher rotation.
In a permanent magnet motor having a rotor (1) in which a permanent magnet (3) is installed on the outer peripheral surface of a rotor iron core, a blower blade formed at at least one location between adjacent permanent magnets on the outer periphery of the rotor. (2) is further included. The blower blade (2) is inclined with respect to a center line (CC) that is equidistant from each permanent magnet, between adjacent axial magnets, from one end to the other end in the axial direction of the rotor core. And it is provided as a linear shape (or curved shape) that is point-symmetric with respect to the midpoint of one end and the other end on the center line.
[Selection] Figure 2

Description

  The present invention relates to a permanent magnet motor that prevents demagnetization of a permanent magnet and deterioration of motor performance due to magnet heat generation, and a method for manufacturing the permanent magnet motor.

  With recent miniaturization and higher rotation of permanent magnet motors, the heat generation density is increasing. For this reason, a mechanism for cooling the motor is required to prevent a decrease in motor characteristics due to a temperature rise of the motor component due to heat generation.

  In a conventional permanent magnet motor, a blower blade is formed on the inner peripheral part of the rotor, and a cooling effect is obtained on the components constituting the motor without using the blower fan due to the fan effect accompanying the rotation of the motor. (For example, refer to Patent Document 1).

Japanese Patent Laid-Open No. 2002-205889

However, the prior art has the following problems.
The permanent magnet motor has a permanent magnet in its rotor, and when the demagnetization due to temperature rise occurs in the permanent magnet due to heat generation of the stator coil and eddy current loss of the permanent magnet, the output performance of the motor is reduced. There is a problem that an adverse effect on motor characteristics such as a decrease occurs.

  With respect to such a problem, in the conventional permanent magnet motor cooling structure as shown in Patent Document 1, the air blowing action is obtained by forming the air blowing blades on the inner peripheral portion of the rotor or the end surface in the rotation axis direction of the rotor. Thus, a structure that directly creates a blowing action between the gap between the stator and the rotor having a large air passage resistance is not provided. For this reason, the parts in the vicinity of the gap including the permanent magnet cannot be sufficiently cooled, and the cooling structure is not necessarily efficient.

  In addition, there has been a problem that it is difficult to further reduce the size and speed of the motor due to the limitation of the temperature rise of the motor components due to the increase in heat generation density due to the downsizing.

  The present invention has been made in order to solve the above-described problems, and prevents permanent magnets from demagnetizing due to heat generation of the magnet and deterioration of motor performance, as well as realizing further downsizing and higher rotation. An object of the present invention is to obtain a permanent magnet motor and a method for manufacturing the permanent magnet motor.

  A permanent magnet motor according to the present invention is a permanent magnet motor having a rotor in which permanent magnets are installed on the outer peripheral surface of a rotor core, and at least one blower blade formed between adjacent permanent magnets on the outer periphery of the rotor. In addition.

  In addition, the method of manufacturing a permanent magnet motor according to the present invention includes a rotor having a permanent magnet installed on the outer peripheral surface of the rotor core, and a blower formed at least at one or more locations between adjacent permanent magnets on the outer periphery of the rotor. A method of manufacturing a permanent magnet motor further having a blade, wherein the rotor core is inclined with respect to a center line that is equidistant from each permanent magnet across one end of the rotor core in the axial direction between adjacent permanent magnets. And a step of forming the blower blade so as to have a linear shape or a curved shape that is point-symmetric with respect to the midpoint of the one end and the other end on the center line.

  According to the permanent magnet motor and the manufacturing method of the permanent magnet motor according to the present invention, the permanent magnet demagnetization due to the heat generated by the magnet and the reduction of the motor performance can be achieved by providing the blower blade on the outer periphery of the rotor that generates a blowing action when the motor rotates. A permanent magnet motor and a method for manufacturing the permanent magnet motor can be obtained that can prevent and achieve further downsizing and higher rotation.

It is a figure which shows schematic structure of the permanent magnet motor in Embodiment 1 of this invention. It is a figure which shows the arrow A of FIG. 1 in Embodiment 1 of this invention. It is a figure which shows the BB cross section of FIG. 2 in Embodiment 1 of this invention. It is the figure which showed the ventilation effect | action by the ventilation blade at the time of motor rotation in the permanent magnet motor in Embodiment 1 of this invention. It is a figure which shows the arrow A of FIG. 1 in Embodiment 1 of this invention.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of a permanent magnet motor and a method of manufacturing a permanent magnet motor according to the invention will be described with reference to the drawings.

Embodiment 1 FIG.
FIG. 1 is a diagram showing a schematic configuration of a permanent magnet motor according to Embodiment 1 of the present invention. The permanent magnet motor shown in FIG. 1 includes a rotor 1, a blower blade 2, a permanent magnet 3, and a rotor shaft hole 4. The permanent magnet motor according to the first embodiment is technically characterized in that the blower blades 2 are provided on the outer peripheral portion of the rotor 1.

  FIG. 2 is a diagram showing an arrow A in FIG. 1 according to Embodiment 1 of the present invention. Moreover, FIG. 3 is a figure which shows the BB cross section of FIG. 2 in Embodiment 1 of this invention. In the permanent magnet motor configured as described above, the rotation of the motor (here, the rotation direction means clockwise or counterclockwise in FIG. 2 and will be described as clockwise in this example), The blades 2 produce a blowing action in the direction of the rotation axis (which means the vertical direction in the drawing of FIG. 2 and will be described as a downward direction in this example).

  FIG. 4 is a diagram showing a blowing action by the blowing blade 2 when the motor rotates in the permanent magnet motor according to the first embodiment of the present invention. In FIG. 4, the rotor 1, the permanent magnet 3, the frame 5, the stator coil 6, the motor boss 7, the output shaft 8, and the stator 9 are shown.

  The blower blade 2 according to the first embodiment has a blower action (meaning the right direction in FIG. 4, and an arrow in FIG. It is possible to generate wind directly on parts (such as the permanent magnet 3, the stator coil 6, and the stator 9) in the stator-rotor gap. That is, by providing the blower blade 2 on the outer peripheral portion of the rotor 1, components near the gap including the permanent magnet 3 can be efficiently cooled.

  Here, as shown in FIG. 2, the blower blades 2, as shown in FIG. 2, center lines (equal distances from the respective permanent magnets 3 from one end to the other end in the axial direction of the rotor core between the adjacent permanent magnets 3. 2 is equivalent to CC in FIG. 2, and is point-symmetric with respect to the midpoint of one end and the other end on the center line (corresponding to the intersection of BB and CC in FIG. 2). It is provided as a linear shape.

  Therefore, with respect to the rotation of the motor in the reverse direction (corresponding to the counterclockwise direction in FIG. 2), the same air flow in the direction of the rotation axis opposite to the above (corresponding to the upward direction in FIG. 2 and to the left in FIG. 4). An effect occurs. Therefore, the gap vicinity can be efficiently cooled regardless of the rotation direction of the motor.

  Further, as shown in FIG. 3, in the blower blade 2, the radial height of the rotor core is equal to or less than the height of the permanent magnet 3 in the radial direction. By having such a height relationship, the blower blade 2 does not protrude from the permanent magnet 3 in the radial direction, and can prevent interference with other components.

  FIG. 5 is a diagram showing an arrow A in FIG. 1 according to Embodiment 1 of the present invention, and shows a blower blade 2 having a shape different from that of FIG. The shape of the blower blade 2 is such that a center line that is equidistant from each permanent magnet 3 from one end to the other end in the axial direction of the rotor core between the adjacent permanent magnets 3 (in FIG. 5, EE If the shape is inclined with respect to the center point and symmetrical with respect to the midpoint of one end and the other end on the center line (corresponding to the intersection of DD and EE in FIG. 5), 2 is not limited to the linear shape as shown in FIG. 2, but may be a curved shape as shown in FIG.

  In addition, the DD cross section in FIG. 5 is equal to previous FIG. Further, in the curved fan blade 2 shown in FIG. 5, the height in the radial direction of the rotor core is equal to or less than the height of the permanent magnet 3 in the radial direction, similarly to the straight fan blade 2 shown in FIG. 2. It has become.

  As described above, according to the first embodiment, the rotor outer peripheral portion of the permanent magnet motor is provided with the blower blades that generate the blowing action when the motor rotates. By such an air blowing action, wind can be generated directly between the stator-rotor gaps. As a result, it is possible to prevent the permanent magnet from demagnetizing due to the heat generation of the permanent magnet and the deterioration of the motor performance by improving the cooling capability of the permanent magnet. Furthermore, by improving the self-cooling ability of the motor, the permanent magnet motor can be further reduced in size and increased in rotation.

  In addition, in FIG. 1, although the case where the ventilation blade 2 is provided in all the locations between the adjacent permanent magnets 3 is illustrated, this invention is not limited to such a structure. By providing the blower blades 2 in at least one place, it is possible to produce a blowing action for obtaining the effects of the present invention.

  1 rotor, 2 blower blades, 3 permanent magnet, 4 rotor shaft hole, 5 frame, 6 stator coil, 7 motor boss, 8 output shaft, 9 stator.

Claims (6)

In a permanent magnet motor having a rotor in which a permanent magnet is installed on the outer peripheral surface of the rotor core,
A permanent magnet motor further comprising a blower blade formed in at least one location between adjacent permanent magnets on the outer periphery of the rotor. The permanent magnet motor according to claim 1,
The blower blade is inclined with respect to a center line that is equidistant from each permanent magnet from one end to the other end in the axial direction of the rotor core between the adjacent permanent magnets, and on the center line. The permanent magnet motor is provided as a linear shape that is point-symmetric with respect to the midpoint of the one end and the other end. The permanent magnet motor according to claim 1,
The blower blade is inclined with respect to a center line that is equidistant from each permanent magnet from one end to the other end in the axial direction of the rotor core between the adjacent permanent magnets, and on the center line. The permanent magnet motor is provided in a curved shape that is point-symmetric with respect to a midpoint of the one end and the other end of the permanent magnet motor. The permanent magnet motor according to claim 2 or 3,
The permanent magnet motor, wherein the blower blade has a radial height of the rotor core equal to or less than a height of the permanent magnet in the radial direction. The permanent magnet motor according to any one of claims 1 to 4,
The said ventilation blade is arrange | positioned in all between the said adjacent permanent magnets. The permanent magnet motor characterized by the above-mentioned. A method for producing a permanent magnet motor having a rotor in which permanent magnets are installed on the outer peripheral surface of a rotor core, and further comprising blower blades formed at least one place between adjacent permanent magnets on the outer periphery of the rotor,
Between the adjacent permanent magnets, it is inclined with respect to a center line that is equidistant from each permanent magnet over one end in the axial direction of the rotor core, and the one end on the center line and the A method of manufacturing a permanent magnet motor, comprising the step of forming the blower blade so as to have a linear shape or a curved shape that is point-symmetric with respect to the midpoint of the other end.

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