JPH0247191B2 - KAITENDENKYOHOORUKOA - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a pole core of a rotating electric machine such as a starter motor.

Conventionally, in the field-wound stator of a starter motor, the flange shape 2 as shown in Fig. 1 has been used.
I was using Pole Core 1. As shown in Fig. 2, the stator of the starter motor is constructed by sandwiching the field coil 4 between the pole core 1 and screwing it to the yoke 3, or by fixing the pole core 1 to the yoke 3 by caulking or welding, and then attaching the field coil to the yoke 3. 4 is directly wound around the pole core 1.

By the way, in the conventional direct-wound field coil system described above, the pole core width A is determined so that the field coil 3 does not come off the pole core collar 2, but since the pole angle θ at this time is larger than the ideal pole angle, leakage magnetic flux The disadvantage was that the magnetic flux increased, the effective magnetic flux decreased, and the performance and rectifying effect were poor.

The object of the present invention is to improve performance by improving the leakage magnetic flux and to extend brush life by improving rectification.

That is, in the present invention, excellent effects can be obtained without sacrificing direct winding workability by cutting out a part of the pole core flange to make the pole core width equal to that at the ideal pole angle.

The present invention will be described below with reference to embodiments shown in the drawings. Figure 3 shows the magnetic flux distribution of the yoke. The solid line shows the magnetic flux distribution due to the conventional pole core 1 shown in FIG. 1, and the broken line shows the magnetic flux distribution due to the pole core 5 according to the embodiment of the present invention shown in FIG. 4.

As shown in Fig. 3, the conventional pole core 1
In the case of a yoke that uses There was a problem with the brushes wearing out prematurely.

According to the pole core 5 according to the present embodiment shown in FIG. 4, the recess 8 is provided in the pole core collar 6 in the circumferential direction from the end surface of the collar 6 toward the boss 7, and the cross-sectional area of the collar 6 is By continuously decreasing the force S1→S2→S3 toward the end face of the flange 6, the magnetic flux distribution changes continuously as shown by the broken line in FIG. 3, so the rectifying action of the brush is significantly improved. The motor rotation speed is increased and the brush life is improved.

The results of this experiment are shown in FIG. Here, the solid line is for the conventional pole core 1, and the broken line is for the pole core 5 according to this embodiment, and the load current I
The characteristics of rotational speed N, output P, and torque T with respect to each other are shown respectively. Further, by adopting such a shape, the following effects can be obtained.

Conventionally, when determining the pole core chip width A in FIG.
and the optimum width calculated from the magnetic circuit, but in reality it is often determined by the above factors. In particular, in the case of a series field coil in which the pole core 1 is fixed to the yoke 3 with screws or welding, primary insulation treatment is performed, and the field coil 4 is directly wound. The pole core angle may be separated from the pole core flange 2, so the optimal pole core angle according to the above is usually a pole core angle larger than {(pole core opening angle θ°) × (number of pole cores P) ÷ 360° = 0.65 to 0.75} (0.7~0.85)
I'm taking it. Therefore, as shown in Figure 6,
When the magnetic flux leaking directly from the pole core flange 2 to the yoke 3 or the adjacent pole core flange 2' without passing through the armature 9 increases, and the optimum pole core angle is taken as shown in Fig. 5. The motor torque was lower than (the torque shown by the broken line) (the torque T shown by the solid line).

However, according to this embodiment, as shown in FIG. 4, the pole core width B required to hold the winding is
While ensuring this, leakage of magnetic flux from the pole core flange 6 can be suppressed by the recess 8, leading to an improvement in the magnetic circuit and an increase in the torque of the motor.

Furthermore, by forming the recess 8 in the middle portion of the collar 6, which is not related to holding down the windings, there is also the effect of weight reduction.

In the above-mentioned embodiment, a pair of recesses 8 with sloped sides were formed in the middle part of the collar 6, but a recess 8a with parallel sides as shown in FIG. Two pairs of recesses 8b are provided as shown in FIG.
Alternatively, as shown in FIG. 7d, a plurality of recesses 8d may be provided alternately on both sides of the collar portion 6 so that the recesses 8d correspond to the protrusions of adjacent pole cores.

Further, in FIGS. 8a, b, and c, recesses 8c, 8f, and 8g are also formed in the axial portion of the collar portion 6.

In addition, in each of the above embodiments, the pole core angle obtained by {(opening angle θ of the end face of the pole core flange portion 6)×number P of pole cores 5)÷360} is
0.65 or more, and more preferably, when the shape of the recess is converted so that the cross-sectional area of the collar 6 is the same and the end surface of the collar 6 is a straight line,
The pole core angle is set in the range of 0.65 to 0.75.

In each of the embodiments described above, the present invention was applied to a starter motor, but it can be applied not only to other motors but also to rotating electric machines such as generators.

[Brief explanation of drawings]

Figure 1 is a perspective view showing a conventional pole core, Figure 2 is a perspective view showing a conventional pole core.
The figure is a front view showing a conventional stator, Figure 3 is a magnetic flux distribution diagram in the conventional and present invention pole cores, and Figure 4 is a front view showing a conventional stator.
Figures a and b are front and bottom views showing an embodiment of the pole core of the present invention, Figure 5 is a characteristic diagram of the conventional pole core and the pole core of the present invention, and Figure 6 is the main part showing the state of magnetic flux leakage in a conventional rotating electric machine. The sectional views, FIGS. 7a to d, and 8a to 8c are bottom views and plan views respectively showing other seven embodiments of the pole core of the present invention. 5...Pole core, 6...Brim part, 7...Boss part, 8
a~8g...Concave portion.

Claims (1)

[Claims] 1 {(opening angle θ of end face of pole core brim)×
(Number of pole cores P) ÷ 360} In the case where the pole core angle obtained by A pole core for rotating electric machines that changes in the circumferential direction. 2 When the shape of the recess is converted so that the cross-sectional area of the brim is the same and the end face of the brim is a straight line, the pole core angle is 0.65 to
A pole core for a rotating electrical machine according to claim 1, wherein the pole core is within the range of 0.75. 3. A pole core for a rotating electric machine according to claim 1 or 2, wherein each of the recessed portions is configured to correspond to a convex portion of an adjacent pole core.