JPH02266859A - Stator for dc machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a field structure of a stator in a DC machine and a method of manufacturing the same.

[Conventional technology]

In the conventional device, as described in Japanese Patent Application Laid-open No. 48-39906, the commutating poles are excited using armature reaction, and a control winding is further provided to control the magnetic flux generated in the commutating poles. It was composed of

[Problem to be solved by the invention]

The above-mentioned conventional technology does not take into consideration the permanent demagnetization of the permanent magnet placed on the demagnetizing field side of the armature reaction, and there is a problem that the performance of the DC machine deteriorates due to permanent demagnetization in practical use.

Furthermore, since the amount of magnetic flux of the commutating pole is controlled by the control winding, if the magnetic flux is controlled to increase, the no-load rotation speed will decrease, and if the magnetic flux is controlled to decrease, the torque will decrease. was there.

An object of the present invention is to prevent permanent demagnetization of a permanent magnet and to increase magnetic flux by a control winding of a commutating pole.

[Means to solve the problem]

In order to achieve the above object, a field structure is used in which a permanent magnet is juxtaposed on the magnetizing field side of the armature reaction, and a winding field is juxtaposed on the demagnetizing field side.

[Effect]

By arranging the permanent magnet on the side of the magnetizing field of the armature reaction in the field pole of the DC machine, the demagnetizing field of the armature reaction does not act on the permanent magnet, so permanent demagnetization of the permanent magnet does not occur. Therefore, a stable amount of magnetic flux can be obtained from the permanent magnet.

Further, by arranging a winding field on the same demagnetizing field side, a series winding characteristic can be obtained. That is, when the load is high, a large current increases the amount of magnetic flux and high torque is obtained, and when the load is light, a low current allows high rotation.

Therefore, by combining permanent magnets and wire-wound fields, it is possible to obtain a DC machine with higher performance than conventional machines.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG.

1 is a stator of a DC machine, 2 is a cylindrical yoke, 3 is a permanent magnet fixed to the inner periphery of the yoke, 4 is a magnetic pole around which a field winding 5 is wound; The field pole 6 is constituted by the above. Reference numeral 7 denotes an armature, which is formed by winding an armature winding 8.

FIG. 2 is a view of the configuration of the field poles as seen from the center of the stator 1. The axial length Lp of the magnetic poles 4 is determined to be approximately equal to the stacking thickness of the armature core, but the axial length of the permanent magnets 3.

is set to be larger than the above stacking thickness in order to increase the effective magnetic flux from the permanent magnet.

Furthermore, FIG. 3 shows a structure in which the permanent magnet 3 is U-shaped and is also placed on the side surface of the field winding 5.

The operation of the above configuration will be explained with reference to FIG. First, when the switch 10 is turned on, the current flowing from the battery 9 passes through the field winding 5, excites the magnetic pole 4, passes through the armature 7, and returns to the - battery again.

In such an operation, the amount of magnetic flux of the field pole is smaller than that of a machine with only a wound field because the amount of magnetic flux from the permanent magnet 3 passes through the armature core in the region where the armature current Ia is small, as shown in Figure 5. Since a large amount of magnetic flux can be obtained, large torque can be obtained.

Next, in a region where the armature current Ia is large, in addition to the large amount of magnetic flux from the field winding, the amount of magnetic flux from the permanent magnet is also added, so a larger amount of magnetic flux is obtained, which makes it possible to generate a larger torque. .

In an intermediate range of armature current, torque characteristics between those of the conventional permanent magnet type and the wound field type can be obtained.

Further, in FIG. 1, when the armature winding is energized, a demagnetizing field acts on the magnetic pole 4 side and an increasing field acts on the permanent magnet 3 side due to armature reaction. For this reason, permanent magnets do not suffer from permanent demagnetization, so defects that degrade performance do not occur under any usage conditions. Furthermore, since the coercive force of the permanent magnet performance may be small, a magnet with a large residual magnetic flux density can be selected, so that the effect of increasing the amount of magnetic flux of the field pole can be obtained.

Figure 2 shows the magnetic pole length of the field pole, but the axial length L of magnetic pole 4 is
Even if p is made thicker than the iron core lamination of the armature 7, it will not have the effect of increasing the amount of magnetic flux, but since the axial length of the permanent magnet 3 will have an effect on increasing the torque, L p < L - Stapling torque performance is improved.

FIG. 3 shows a structure that further improves performance by effectively utilizing the magnetic flux at the end of the permanent magnet.

Note that the inner diameter dimension of the permanent magnet 3 and the inner diameter dimension of the magnetic pole 4 do not have to be the same, and a difference may be provided in either one.

Further, the magnetic pole 4 may be fixed as a separate molded product, or may be a laminated core punched out at the same time as the yoke.

〔Effect of the invention〕

According to the present invention, in a region where the armature current is small, higher torque than the wire-wound type and higher rotation performance than the magnet type can be obtained.
In areas where the armature current is large, the magnetic circuit configuration provides higher torque performance than the magnetic type, so conventional DC machines have advantages and disadvantages and are limited in their applications.
The present invention has the advantage that it can be used in a wide range of applications.

Furthermore, since there is no permanent demagnetization of the permanent magnet, there are no restrictions on the usage conditions and the range of applications can be expanded.

[Brief explanation of drawings]

FIG. 1 is a front view of the main parts of a DC machine showing one embodiment of the present invention;
Figures 2 and 3 are plan views of the field poles viewed from the center;
The figure is a circuit diagram of one embodiment, and FIG. S is a diagram showing the amount of field pole magnetic flux with respect to armature current of one embodiment. 1...Stator, 2...Yoke, 3...Permanent magnet, 4
...m pole, 5...field winding, 6...field pole, 7.
...Armature, 8...Electronic chart diagram

Claims (1)

[Claims] 1. In the stator of a DC machine consisting of a yoke, a permanent magnet, and a winding field, the magnetic pole structure is characterized by juxtaposing the permanent magnet on the side of the increasing field of armature reaction and the winding magnetic field on the side of the demagnetizing field. Stator of DC machine.