JPH0560148U - Permanent magnet synchronous motor - Google Patents

Abstract

(57) [Summary] [Purpose] The shaft of the electric motor was made circular to reduce the number of steps and processes. [Structure] A circular shaft and a ring-shaped permanent magnet fitted to the shaft are provided and magnetized by being divided in the circumferential direction.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a rotor of a permanent magnet synchronous motor (referred to as PM motor).

[0002]

[Prior art and its problems]

 In the rotor core of the PM motor, as shown in FIG. 2, electromagnetic steel plates 3 each having a damper slot 2 formed around a shaft 1 are axially laminated, and between the electromagnetic steel plates 3 there are four poles radially as shown. In this case, the permanent magnets 4a for four poles are inserted, and the permanent magnets 4b are also inserted between the four-sided cut shaft 1 and the electromagnetic steel plate 3.

In this case, since the permanent magnet 4b inserted between the electromagnetic steel plate 3 and the shaft 1 has a square pole shape, the inner diameter shape of the steel plate 3 and the shaft cross-sectional shape are also formed in a quadrangle. Therefore, regardless of the inner diameter shape of the electromagnetic steel plate 3, the shaft 1 is manufactured by four-sided cutting, which increases the number of manufacturing processes and requires precision, which causes a problem of increasing man-hours.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a PM motor with a reduced number of shaft manufacturing steps and man-hours.

[0005]

[Means for Solving the Problems]

 The structure of the present invention that achieves the above-mentioned object is a rotor of a permanent magnet synchronous motor in which a permanent magnet is inserted between a shaft and electromagnetic steel sheets laminated in the axial direction. It is characterized in that a ring-shaped permanent magnet magnetized by being divided in the circumferential direction is inserted between the two.

[0006]

[Function] A ring-shaped permanent magnet is divided into magnets in the circumferential direction and magnetized to form permanent magnets corresponding to the number of poles. Since the ring-shaped permanent magnet is used, the shaft can also be manufactured to have a circular cross section. Is easy to make.

[0007]

【Example】

 An embodiment of the present invention will now be described with reference to FIG. 1 that are the same as those in FIG. 2 are given the same reference numerals. FIG. 1 illustrates an example of four poles as in FIG. In this embodiment, the shaft 1 has a circular cross section, and a ring-shaped permanent magnet 4c is fitted around the shaft 1. The ring-shaped permanent magnet 4c is divided in the circumferential direction according to the number of poles and is alternately magnetized with different poles in the thickness direction. The ring-shaped permanent magnet 4c has a four-pole structure together with the radially arranged permanent magnets 4a. Have.

Electromagnetic steel plates 3 are laminated outside the permanent magnets 4 c, and permanent magnets 4 a are radially inserted between the electromagnetic steel plates 3. Therefore, the 1/4 portion of the electromagnetic steel sheet 3 shown in FIG. 1 is surrounded by the radial permanent magnets 4a and the ring-shaped permanent magnets 4c, respectively, and has the same magnetic pole, for example, only N pole or N pole or S pole. Then it will be surrounded by only the S pole.

[0009]

[Effect of the device]

 As described above, according to the present invention, the permanent magnet inserted between the electromagnetic steel plate and the shaft has a ring shape, and the shaft has a circular cross section. Is unnecessary, the shaft can be easily manufactured in a shorter time than before, and the product is inexpensive.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of the present invention.

FIG. 2 is a configuration diagram of a conventional example.

[Explanation of symbols]

 1 shaft 3 electromagnetic steel plate 4a, 4b permanent magnet 4c ring-shaped permanent magnet

Claims (1)

[Scope of utility model registration request] 1. A rotor of a permanent magnet synchronous motor in which a permanent magnet is inserted between a shaft and an electromagnetic steel sheet laminated in the axial direction, wherein a circumferential direction is provided between the shaft having a circular cross section and the electromagnetic steel sheet. A permanent magnet synchronous motor characterized in that a ring-shaped permanent magnet that is divided and magnetized is inserted.