JP2004135475A - Permanent magnet motor rotor - Google Patents

Abstract

Provided is a permanent magnet type electric motor in which a magnetic gap between a tiled magnet and a stator can be optimally set, and characteristics of the electric motor can be improved.
A rotor (1) of a permanent magnet type motor in which a rotor core (3) is fitted on an outer peripheral surface of a shaft (2) and a plurality of tile-shaped magnets (4) are arranged on the outer peripheral surface of the rotor core (3). A dovetail groove 5 extending in the axial direction is formed at a circumferential pitch equal to the pitch at which the tile magnets 4 are arranged in the circumferential direction. In addition, an engaging piece 6 of a non-magnetic material having an I-shaped cross section is disposed on the outer peripheral surface of the rotor core 3 so that both ends are located at the positions of the dovetail groove 5, and one end is a tile-shaped magnet The other end is inserted into the dovetail groove 5 so as to engage with the outer peripheral surfaces of both ends of 4.
[Selection diagram] Fig. 1

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a rotor of a permanent magnet type electric motor in which a rotor core is fitted on an outer peripheral surface of a shaft and a plurality of tiled magnets are arranged on the outer peripheral surface of the rotor core.
[0002]
[Prior art]
In a rotor of a conventional permanent magnet type electric motor, a tile magnet is fixed to an outer peripheral surface of a rotor core fitted and fixed to an outer peripheral surface of a shaft with an adhesive. Further, the entire tile-shaped magnet is covered with a tubular member so that the tile-shaped magnet is not scattered (for example, Patent Document 1).
[0003]
[Patent Document 1]
JP-A-9-149570 (FIGS. 1 and 2)
[0004]
[Problems to be solved by the invention]
However, in such a conventional technique, since the tile-shaped magnet is covered with the tubular member, there is a problem that the magnetic gap between the tile-shaped magnet and the stator is increased, and the characteristics of the electric motor are deteriorated.
The present invention has been made in order to solve such a problem, and provides a permanent magnet type electric motor capable of optimally setting a magnetic gap between a tiled magnet and a stator, and improving the characteristics of the electric motor. The purpose is to do so.
[0005]
[Means for Solving the Problems]
In order to solve the above-described problem, the present invention provides a rotor of a permanent magnet type electric motor in which a rotor core is fitted to an outer peripheral surface of a shaft and a plurality of tiled magnets are arranged on the outer peripheral surface of the rotor core. On its outer peripheral surface, a dovetail groove extending in the axial direction is formed at a circumferential pitch equal to the circumferential pitch of the tile magnet, and the tile magnet has a diameter at both ends in the circumferential direction greater than that at the center. An engaging piece of a non-magnetic material having an I-shaped cross section is disposed on the outer peripheral surface of the rotor core so that the both ends are located at the positions of the dovetail groove. The other end is inserted into the dovetail groove so as to engage with the outer peripheral surfaces of both ends of the magnet.
[0006]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a front sectional view showing a rotor of a permanent magnet type electric motor according to an embodiment of the present invention. FIG. 2 is an enlarged view of a main part in FIG.
1 and 2, 1 is a rotor, 2 is a shaft, and 3 is a rotor core fitted and fixed to the outer peripheral surface of the shaft, which is formed by laminating electromagnetic steel plates. The rotor core 3 has a plurality of tiled magnets 4 adhered and fixed at equal intervals in the circumferential direction on the outer peripheral surface. Further, the rotor core 3 has a dovetail groove 5 extending in the axial direction on the outer peripheral surface. The dovetail groove 5 is formed at a circumferential pitch equal to the circumferential arrangement pitch of the tile-shaped magnet 4.
The tile-shaped magnet 4 is configured such that the diameter of both ends in the circumferential direction is smaller than that of the center part, and is arranged on the outer peripheral surface of the rotor core 3 so that the both ends are located at the positions of the dovetail grooves 5. I have.
One end of a nonmagnetic engaging piece 6 having an I-shaped cross section is inserted into each dovetail 5. The other ends of the engagement pieces 6 are engaged with the outer peripheral surfaces of both ends of the tile-shaped magnet 4. The engaging piece may be formed of a nonmagnetic metal rod, or may be formed by laminating nonmagnetic metal and bonding or welding.
Since the rotor 1 has such a configuration, even if a large centrifugal force acts on the tile-shaped magnet 4 due to the rotational drive, the tile-shaped magnet 4 is pressed by the engagement piece 6, so that the tile-shaped magnet 4 does not scatter. . Further, since the engagement piece 6 is located at a so-called concave portion of the tile-shaped magnet 4, the magnetic gap between the tile-shaped magnet 4 and a stator (not shown) does not increase, and is a non-magnetic material. Therefore, the magnetic circuit is not adversely affected. Therefore, the characteristics of the electric motor are improved as compared with the related art.
[0007]
【The invention's effect】
As described above, according to the present invention, the magnetic gap can be set to the optimum value without affecting the magnetic circuit, so that the characteristics of the electric motor can be improved.
[Brief description of the drawings]
FIG. 1 is a front sectional view showing a rotor of a permanent magnet type electric motor according to an embodiment of the present invention.
FIG. 2 is an enlarged view of a main part in FIG.
[Explanation of symbols]
Reference Signs List 1 rotor 2 shaft 3 rotor core 4 tile-shaped magnet 5 dovetail groove 6 engaging piece

Claims (3)

A rotor of a permanent magnet type motor in which a rotor core is fitted to an outer peripheral surface of a shaft and a plurality of tile-shaped magnets are arranged on an outer peripheral surface of the rotor core.
The rotor core has, on its outer peripheral surface, a dovetail groove extending in the axial direction at a circumferential pitch equal to the circumferential arrangement pitch of the tile-shaped magnet,
The tile-shaped magnet is configured such that the diameter of both ends in the circumferential direction is smaller than the center part, and is disposed on the outer peripheral surface of the rotor core so that the both ends are located at the positions of the dovetail grooves.
That the engaging piece of the non-magnetic material having the I-shaped cross section is such that one end is engaged with the outer peripheral surfaces of both ends of the tile-shaped magnet, and the other end is inserted into the dovetail groove. Characteristic rotor of permanent magnet type motor. The rotor of a permanent magnet type electric motor according to claim 1, wherein the engagement piece is formed of a non-magnetic metal rod. The rotor of a permanent magnet type electric motor according to claim 1, wherein the engagement piece is formed by laminating a nonmagnetic metal and bonding or welding the nonmagnetic metal.

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