JPH04111279U - Permanent magnet field type DC rotating machine - Google Patents

Abstract

(57) [Summary] [Purpose] To reduce cogging torque without changing the curvature of the inner peripheral surface of a permanent magnet type field pole. [Structure] In a permanent magnet field type DC rotating machine 1 having a plurality of stator field magnet magnetic poles 4 to 7, the length of the field magnet magnetic poles 4 to 7 in the rotation axis direction X of the DC rotating machine is The length is made shorter toward the end in the circumferential direction Y to prevent the distribution of field magnetic flux along the circumferential direction from changing rapidly and to suppress the generation of cogging torque.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention is a permanent magnet field that can reduce cogging torque. This relates to a type of DC rotating machine.

0002

[Conventional technology]

For example, a salient pole armature core is used in the rotor, and a field permanent magnet is used in the stator. In a permanent magnet field type DC rotating machine, the interaction between the rotor and stator is However, there was a problem in that cogging torque was generated due to use. In order to solve this problem, we developed a permanent magnet in the shape of a fan-shaped arc along the inner cylindrical surface of the magnetic material. In a rotating machine with a plurality of stones arranged and a rotor placed inside a hollow part of a permanent magnet, Each of the plurality of sector-shaped arcuate permanent magnets has an outer circumferential surface and an inner circumferential surface excluding the circumferential end. In addition, the inner peripheral surface curvature is reduced at the circumferential end. By making the diameter smaller than the center part in the circumferential direction, the inner peripheral surface of the permanent magnet and the rotor are The radial dimension of the magnetic gap formed by the outer circumferential surface at the circumferential end of each permanent magnet. and the outer and inner circumferential surfaces of each permanent magnet are perpendicular to each other. The structure consists of two planes that are connected to each other with continuous and rapid changes. A structure for reducing the cogging torque was disclosed in Japanese Patent Publication No. 63-29504. It is shown.

0003

[Problem that the idea aims to solve]

By the way, rotating machines use two or more segment-shaped magnetic poles, When these magnetic poles are attached to the stator yoke, there may be variations in the attachment. In this case, processing is required to correct this variation after installation. However, the conventional technology using magnet magnetic poles with changed curvature as described above If the magnetic poles are processed after they are installed, the electrical characteristics may change. As a result, when the magnet magnetic poles are attached to the yoke, there may be unevenness in the attachment. However, the problem is that machining after attaching the magnetic poles is extremely difficult. has a problem. Furthermore, as mentioned above, since the curvature of the inner circumference of the field magnet magnetic pole is not constant, , a ring-shaped field magnet in which each segment is integrally and continuously provided in a ring shape. It is also difficult to form magnetic poles, as well as uneven air gaps and cogging torque. It also has the disadvantage that it is difficult to analyze the relationship between them by calculation. The purpose of the present invention is therefore to solve the above-mentioned problems in the prior art. The purpose of the present invention is to provide a permanent magnet field type DC rotating machine that can perform

0004

[Means to solve the problem]

The feature of this invention to solve the above problem is that multiple stator field magnet magnetic poles In a permanent magnet field type DC rotating machine having The curvature of the inner circumference is constant, and the length of the DC rotating machine in the direction of the rotation axis is at the center of the circumference. It is at the longest point and becomes shorter towards the circumferential end. . The above magnetic poles are integrally formed as ring-shaped magnetic poles. Good too.

[0005]

[Effect]

The length of the field magnet magnetic pole in the direction of the rotation axis of the DC rotating machine is as shown above. Since it is made to become shorter toward the circumferential end, this makes it possible to The distribution of field magnetic flux does not change suddenly, and the generation of cogging torque is suppressed. can be done.

[0006]

【Example】

Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

[0007] Figure 1 shows a permanent magnet field having multiple stator field magnet magnetic poles according to the present invention. 2 is a schematic cross-sectional view of a type of DC rotating machine 1, and 2 is a casing (not shown) that is rotatably mounted. The supported armature, 3, is a yoke. The yoke 3 is a cylindrical magnetic It is made of a flexible material and is arranged concentrically with the armature 2, and the inner peripheral surface 3A of the yoke 3 has a , a plate-shaped magnet member that is a permanent magnet is used as a magnetic pole by an appropriate means. Fixed.

[0008] In the illustrated embodiment, four magnet members 4 to 4 are made to have the same size and shape. 7 are arranged at 90 degree intervals in the circumferential direction of the yoke 3, and at appropriate spacing from adjacent magnet members. The magnetic poles of the 4-pole stator field magnet are arranged so as to be spaced apart from each other. Ru.

[0009] In Fig. 2, one magnet member 4 constituting the field magnet magnetic pole is shown in front. As can be seen from FIG. 1, this magnet member 4 has its outer peripheral surface 4A The curvature is determined to be the same as the curvature of the inner peripheral surface 3A of the yoke 3. Magnet member 4 is a curved member with a constant wall thickness, therefore, any direction perpendicular to its outer circumferential surface 4A The distance between the outer circumferential surface 4A and the inner circumferential surface 4B measured along the line of interest is constant. be.

0010 The length of the magnet member 4 in the rotation axis direction (X) of the DC rotating machine 1 can be seen from FIG. , the maximum length LX is near the center in the circumferential direction (Y), and It becomes shorter towards the end. In the illustrated embodiment, the magnetic member 4 is , is a curved rectangular plate-like member that forms part of a cylinder as a whole, and its axis of rotation is The two lines 4C and 4D along the line are shaped like an arc. The magnetic poles that make up the other magnetic poles The net members 5, 6, and 7 also have exactly the same structure.

[0011] According to this configuration, due to the above-mentioned shape near each end of the magnet members 4 to 7, The magnetic resistance increases as the circumferential ends of the magnet members 4 to 7 are approached. For this purpose, a plurality of (4) formed by the yoke 3 and the magnet members 4 to 7 The strength of the magnetic field applied to the armature 2 by the permanent magnet type field poles of the magnetic poles It is possible to prevent sudden changes near the change line.

0012 Therefore, even if the relative positional relationship between the armature 2 and each field magnetic pole changes, the armature 2 Since the strength of the applied magnetic field does not change suddenly, cogging torque can be kept small. can be done.

[0013] Moreover, each inner circumferential surface of the magnet members 4 to 7 is on a circumferential surface having a predetermined constant curvature. Therefore, even if there is variation in the installation of the magnet components, processing is required to compensate for this. It can be done easily.

[0014] Furthermore, since the magnet members 4 to 7 are curved members with constant wall thickness, the coggin It is easy to simulate torque.

[0015] Another embodiment of the invention is shown in FIG. In the embodiment of FIG. The magnet member attached to the inner peripheral surface of the arc 2 is a curved member with a constant wall thickness. , is formed as a single cylindrical magnet ring 8, and the magnet ring Cutout portions 8A to 8H are formed at both ends of 8. The shape of each of these notches is Similar to the shape of the end of the magnet member 4 shown in FIG. The length is set to become shorter toward the opposite end.

[0016] In this way, the magnet ring 8 has four magnetic poles P1, P2, P3, P4. is formed, and by attaching this magnet ring 8 to the yoke 3, the structure shown in FIGS. Similarly to the rotating machine shown in Fig. 2, the generation of cogging torque can be effectively suppressed. You can get the same effect by doing this.

[0017]

[Effect of the idea]

According to the present invention, as described above, the length of the field magnetic pole can be changed in the circumferential direction. In this way, the cogging torque is reduced by making the field flux uniform. Therefore, by making the curvature of the inner circumferential surface of the magnet member constant, the magnet part In addition to being able to perform finishing processing to correct variations in the installation of materials, Kogi It is easier to simulate the ring torque, and the magnet member can be made into a ring shape. This has effects such as being able to achieve integration.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view showing one embodiment of the present invention.

FIG. 2 is a sectional view taken along line AA in FIG. 1.

FIG. 3 is a perspective view showing essential parts of another embodiment of the present invention.

[Explanation of symbols]

1 DC rotating machine 3 York 4 to 7 Magnet member 4B Inner peripheral surface 8 Magnet ring P1 to P4 magnetic pole

Claims (1)

[Scope of utility model registration request] 1. In a permanent magnet field type DC rotating machine having a plurality of stator field magnetic poles, each of the field magnetic poles is
The permanent motor is characterized in that the curvature of the inner peripheral part is constant, and the length of the DC rotating machine in the direction of the rotational axis is longest at the center in the circumferential direction and becomes shorter toward the ends in the circumferential direction. Magnet field type DC rotating machine.