JPH11332145A - Rotor of motor having magnet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent beforehand a magnet from popping out of a magnet fixing groove by means of a magnet holding plate by providing a magnet inserted and fixed into the fixing groove and a magnet holding member to be engaged with both end portions of magnets mounted at both end surfaces of a rotor core. SOLUTION: A plurality of wedge-type magnet fixing grooves are formed, keeping clearances in the axial direction and circumference direction of the external circumference surface of a rotor core, magnets 2 are inserted and fixed in these grooves, level distance areas are formed at both end portions of the upper surface of each magnet 2, and a magnet holding plate 8 having a collar portion covering on the level difference areas and groove avoiding the end portion 6 of magnetic material at its external circumference surface is placed against both the end surfaces of a rotor core. Thereby, the magnet 2 is prevented from popping out of the magnet fixing groove by means of a centrifugal force. A bonding agent may be also interposed between the collar portion of holding plate 8 and level difference area of magnet 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotor of a motor having a magnet, and more particularly, to the rotation of a motor having a magnet having a magnet fixed to an outer peripheral surface of a rotor core of the motor for the purpose of preventing magnet scattering and reducing the amount of leakage magnetic flux. It is about the child.

[0002]

2. Description of the Related Art Conventionally, when a magnet 2 is fixed to an outer peripheral surface of a rotor core 1 formed by laminating thin plates made of a magnetic material punched out by press working, as shown in FIG. A plurality of magnets 2 are arranged on the outer peripheral surface of the child core 1, and the outer periphery of these magnets 2 is wrapped by a non-magnetic tube 3.

As shown in FIG. 8, a plurality of wedge-shaped magnet fixing grooves 5 are formed on the outer peripheral surface of the rotor core 1 and are spaced apart in the circumferential direction and extend in the axial direction. Insertion and fixation have been proposed.

However, in the conventional configuration shown in FIG.
It is difficult to fix the non-magnetic tube 3 to the rotor core 1 while maintaining concentricity with the rotor shaft 4. In addition, the non-magnetic tube 3
The air gap is widened by the thickness of the motor, and the motor characteristics deteriorate.

In the configuration shown in FIG.
However, there was a drawback that it jumped out of the groove 5.

The present invention has been made to eliminate the above disadvantages.

[0007]

SUMMARY OF THE INVENTION A rotor of a motor having a magnet according to the present invention comprises a rotor core of a motor, a wedge-shaped magnet fixing groove formed on an outer peripheral surface of the rotor core so as to extend in an axial direction. A magnet inserted and fixed in the fixing groove, and a magnet holding member attached to both end faces of the rotor core and engaged with both ends of the magnet.

Further, in the rotor of the electric motor having the magnet according to the present invention, both ends, or both ends and an intermediate part thereof are formed between the fixing grooves on the outer peripheral surface of the rotor core. It has a notch.

Further, in the rotor of the electric motor having the magnet according to the present invention, the magnet has a step at both end portions of the upper surface thereof, and the magnet holding plate has a flange portion which covers the step of the magnet. I do.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

In the present invention, as shown in FIG. 1, a plurality of wedge-shaped magnet fixing grooves 5 are formed on the outer peripheral surface of the rotor core 1 so as to be axially spaced apart from each other in the circumferential direction. 2 and 3, a step 7 is formed at both ends of the upper surface of each magnet 2, and a flange 8a over the step 7 and the end portion 6 of the magnetic material are connected to each other. A magnet holding plate 8 having an escape groove 8b on the outer peripheral side thereof is brought into contact with both end surfaces of the rotor core 1 so as to prevent the magnet 2 from jumping out of the magnet fixing groove 5 due to centrifugal force.

An adhesive may be interposed between the flange 8a of the holding plate 8 and the step 7 of the magnet 2, and the center of the side surface of the holding plate 8 is provided on the outer periphery of the rotor shaft 4. It is preferable to provide a collar 9 to be brought into contact with and press the rotor shaft 4 into the collar 9.

Further, as shown in FIG. 4, the groove 5 may have a shape in which the bottom is widened.

Since the rotor of the electric motor having the magnet according to the present invention has the above-described configuration, it is easy to fix the magnet 2 while maintaining the concentricity with the rotor shaft 4. Does not fly out due to centrifugal force. Further, it is also possible to enhance the fastening force by using an adhesive in combination.

In the above-described embodiment, there is a problem that a magnetic flux leaks from the magnet 2 because the magnetic portion exists between the magnet fixing grooves 5.

Therefore, in another embodiment of the present invention, as shown in FIG. 5, the magnetic material portions of the rotor core 1 formed between the magnet fixing grooves 5 are connected to both end portions 6 of the rotor core 1.
Except for cutting.

In this embodiment, as described above, the amount of magnetic material existing between the adjacent magnets 2 is reduced, so that it is difficult for leakage magnetic flux to be generated, thereby securing the amount of magnetic flux that contributes to the torque of the motor. It becomes possible.

Further, since the magnetic portions are only formed at both ends of the rotor core 1 by the above-described cutting, the insertion and fixing of the magnet 2 into the groove 5 are facilitated.

Further, the concentricity between the magnet 2 and the rotor shaft 4 can be easily obtained.

FIG. 6 shows still another embodiment of the present invention in which the magnetic portion is left in the middle part of the rotor core 1 in the embodiment shown in FIG.

[0021]

As described above, the rotor of the motor having the magnet according to the present invention has the above-described structure. There is a great advantage that the concentricity between the rotor and the rotor shaft 4 can be accurately maintained, and the amount of leakage magnetic flux of the magnet can be reduced.

[Brief description of the drawings]

FIG. 1 is a perspective view of a rotor of a motor having a magnet of the present invention.

FIG. 2 is a perspective view of a magnet used for a rotor of an electric motor having the magnet of the present invention.

FIG. 3 is a perspective view of a magnet holding plate used for a rotor of a motor having a magnet according to the present invention.

FIG. 4 is an end view of a rotor core showing another example of the magnet fixing groove in the rotor of the electric motor having the magnet of the present invention.

FIG. 5 is a perspective view of a rotor according to another embodiment of the rotor of the electric motor having the magnet of the present invention.

FIG. 6 is a perspective view of a rotor of still another embodiment of the rotor of the electric motor having the magnet of the present invention.

FIG. 7 is a perspective view of a conventional rotor.

FIG. 8 is a perspective view of another conventional rotor.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rotor core 2 Magnet 3 Non-magnetic tube 4 Rotor shaft 5 Fixing groove 6 End part of magnetic body 7 Step 8 Suppression plate 8a Flange 8b Groove 9 Collar

Claims (4)

[Claims] 1. A rotor core of an electric motor, a wedge-shaped magnet fixing groove formed on an outer peripheral surface of the rotor core so as to extend in an axial direction, a magnet inserted and fixed in the fixing groove, A rotor for a motor having a magnet, comprising: a magnet holding member attached to both end surfaces of a child core and engaged with both end portions of the magnet. 2. The rotor for a motor having a magnet according to claim 1, further comprising a cutout formed on the outer peripheral surface of the rotor core except for both ends between the fixed grooves. 3. An electric motor having a magnet according to claim 1, wherein a cutout portion is formed on the outer peripheral surface of the rotor core between the fixed grooves except for both ends and an intermediate portion. Rotor. 4. The magnet according to claim 1, wherein the magnet has a step at both ends on an upper surface thereof, and the magnet holding plate has a flange portion that covers the step of the magnet.
Or a rotor of an electric motor having the magnet according to 3.