JPH04111278U - 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 the permanent magnet field type DC rotating machine 1, the field pole magnetic members 4, 5, 6, 7 are curved members with constant thickness, and the inner peripheries of the magnetic members 4, 5, 6, 7 are curved. A plurality of grooves 41 to 46 are provided on the surface, and the width and/or depth of these grooves are varied along the circumferential direction of the magnetic member, so that near the switching line of the magnetic pole, the grooves 41 to 46 are formed along the circumferential direction of the magnetic member. , to prevent sudden changes in magnetic field strength.

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 a thin plate-like magnetic part is provided on the inner peripheral surface of the yoke. In a permanent magnet field type DC rotating machine equipped with field magnetic poles arranged with The magnetic member is a curved member with a constant thickness, and the circumferential direction of the inner peripheral surface of the magnetic member is A plurality of grooves are provided along the axial direction of the yoke near the switching line of the magnetic pole in the direction. In order to prevent sudden changes in the strength of the magnetic field along the circumferential direction of the magnetic member, The width and/or depth of the groove is changed along the circumferential direction of the magnetic member. be. A curved member of constant wall thickness includes a cylindrical member of constant wall thickness, but Therefore, the magnetic member may be a cylindrical magnet ring with a constant wall thickness. stomach.

[0005]

[Effect]

The width and/or depth of the plurality of grooves provided in the magnetic member, which is the magnetic pole, This changes the magnetic pole in the circumferential direction of the magnetic member. Cogging prevents the strength of the magnetic field near the split wire from changing suddenly. It is possible to suppress the generation of leakage.

[0006]

【Example】

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

[0007] FIG. 1 is a schematic cross-sectional view of a permanent magnet field type DC rotating machine 1 according to the present invention. 3 is an armature rotatably supported by a casing (not shown), and 3 is a yoke. . The yoke 3 is made of a cylindrical magnetic material and is arranged concentrically with the armature 2. A thin plate-shaped magnetic member, which is a permanent magnet, is attached to the inner peripheral surface 3A of the yoke 3 in an appropriate manner. Fixed by means.

[0008] In the illustrated embodiment, four magnet members 4 to 7 are arranged at 90° in the circumferential direction of the yoke 3. The magnet members are arranged at intervals of 30° and with an appropriate space between adjacent magnet members. It is.

[0009] In FIG. 2, one of the four magnet members 4 is shown enlarged. The magnet member 4 is a curved member with a constant wall thickness, and therefore its outer circumference Between its outer peripheral surface 4A and its inner peripheral surface 4B measured along an arbitrary line perpendicular to the surface 4A The distance is constant. Note that the curvature of the outer peripheral surface 4A is the same as the curvature of the inner peripheral surface of the yoke 3. determined to be the same. The inner circumferential surface 4B is parallel to the axis of the yoke 3. A large number of grooves 41, 42, 43 and 44, 45, 46 are formed.

0010 As can be seen from FIG. 2, the grooves 41 to 43 are concentrated near one end of the magnet member 4. The grooves 44 to 46 are concentrated near the other end. There is. The grooves 41 to 43 have respective widths and depths close to one end of the magnet member 4. It is formed so that it increases as the temperature increases. On the other hand, the grooves 44 to 45 are also The width and depth are formed to increase closer to the other end.

[0011] The other magnet members 5, 6, and 7 have the same shape as the magnet member 4 shown in FIG. has been completed.

0012 According to this configuration, the width and depth are as described above near each end of the magnet members 4 to 7. Because of the grooves that change as shown in Therefore, the magnetic resistance increases, which causes the yoke 3 and the magnetic members 4 to 7 to The strength of the magnetic field generated by the permanent magnetic field pole formed by the There is no sudden change near the dividing line.

[0013] Therefore, even if the relative positional relationship between the armature 2 and the permanent magnet type field pole changes, the electric Since the strength of the magnetic field applied to child 2 does not change suddenly, the cogging torque can be reduced. can be kept to a minimum.

[0014] Moreover, since each inner peripheral surface of the magnet members 4 to 7 is on a predetermined circumferential surface, Even if there are variations in the installation of the net members, processing can be easily performed to correct them. can become.

[0015] Furthermore, since the magnet members 4 to 7 are curved members with constant wall thickness, It is easy to simulate the running torque.

[0016] In addition, in the above embodiment, each end of each magnet member 4 to 7 constituting the field magnetic pole By increasing both the width and depth of the grooves near the ends, the magnetic flux near their ends is Although we tried to avoid sudden changes in the size of the It is easily understood from the above explanation that a configuration in which only the be.

[0017] Another embodiment of the invention is shown in FIG. In the embodiment of FIG. The magnet member attached to the inner peripheral surface of arc 3 is a curved member with a constant wall thickness. , is formed as a single cylindrical magnet ring 8, and the magnet ring Grooves 81 to 86 having the same purpose as the grooves 41 to 46 are formed on the inner circumferential surface 8A of 8. It is different from the embodiment shown in Fig. 1 in that four sets are formed, but its basic function and effect are as follows. is similar to the embodiment of FIG. In addition, in Figure 3, the same parts as in Figure 1 are the same. Reference numerals are given and explanations thereof are omitted.

[0018]

[Effect of the idea] As explained above, according to the present invention, grooves are provided on the inner peripheral surface of the magnet member. Cogging torque can be reduced by changing the width and/or depth of Therefore, it is possible to keep the curvature of the inner peripheral surface of the permanent magnet field pole constant, and Therefore, it is not possible to finish the magnetic member even after it has been attached to the yoke. Ru. In addition, it facilitates cogging torque simulation and links magnetic poles. This has effects such as being able to form a round-shaped magnet structure.

[Brief explanation of drawings]

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

FIG. 2 is an enlarged cross-sectional view of the magnet member in FIG. 1;

FIG. 3 is a schematic sectional view showing another embodiment of the present invention.

[Explanation of symbols]

1 DC rotating machine 3 York 4,5,6,7 Magnet member 41 to 46 groove 8 Magnet ring 81 to 86 groove

Claims (1)

[Scope of utility model registration request] 1. A permanent magnet field type DC rotating machine having a field magnetic pole formed by disposing a thin plate-like magnetic member on the inner peripheral surface of a yoke, wherein the magnetic member is a curved member having a constant wall thickness. In addition, a plurality of grooves are provided along the axial direction of the yoke near the switching line of magnetic poles in the circumferential direction on the inner peripheral surface of the magnetic member, so that the strength of the magnetic field along the circumferential direction of the magnetic member suddenly increases. A permanent magnet field type DC rotating machine characterized in that the width and/or depth of these grooves are varied along the circumferential direction of the magnetic member in order to prevent the grooves from changing.