JPS61258636A - Stator core of rotary electric machine - Google Patents

Abstract

PURPOSE:To increase the stator core strength of a punched plate itself after laminated by disposing both ends of punched core plates at the center of a slot or teath. CONSTITUTION:The first layer punched plates of laminated stator core are the first and second punched plates a1 and b1. The plates a1 and b1 are displaced counterclockwise as a dovetail keyway 3 is seen from above at an angle 1/8.Sp corresponding to 1/8 slot pitch with respect to the center line A of the punched plate. The second layer third laminated punched plates c1, d1 are displayed at the slot position of the sector punched plate so that c1 is the same as a1, d1 is the same as b1, but displaced at the dovetail keyway 3 by an angle 1/8.Sp clockwisely as seen from above with respect to the center line of the punched plate reversely to the plates a1, b1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a stator core for a rotating electrical machine in which the number of slots per sector is n+1/2 (n is any integer).

[Technical background of the invention and its problems]

In order to prevent the generation of eddy currents, the stator core of a rotary machine is constructed by stacking core blanks made of silicon steel sheets with a thin insulation coating. The punched plate is formed as a fan-shaped plate with a slot portion for inserting the stator coil in the inner periphery in the radial direction, and as shown in FIG.
It is usually laminated as a 1/2 lap. Here, ■ is a slot, ■ is a tooth, ■ is a dovetail keyway, (to) is a dovetail key, and ■ is a punched board seam. That is, the punched plate is provided with a dovetail key groove (2) on the fan-shaped outer circumferential side, and is fitted into a dovetail key (to) provided on the stator frame. For punching, the number of sectors is determined so that the number of slots per sector is an integer, but in rare cases, for manufacturing reasons or when changing the number of slots in a modified machine, the dovetail key of the existing frame The number of slots per sector is n + 1/2 because it is necessary to match the pitch of
(n is an integer). In this case, the number of sectors to be punched is of course an even number. In such a case, the basic shape of the punched sheets to be laminated in the first layer is as shown in Figure 4 (a).
.

As shown in the first punched board (a,) and second punched board (b4) in (b), if one end of the sector-shaped punched board is the center of the slot ■, the other end The first and second punched plates (a
J-(b4) are arranged alternately. And, the punched board laminated in the second layer at 172 laps is a dovetail key groove.
Make sure that the positional relationship between the slots and the
The center of the slot shown in (C0) of C) is the punching center line (A)
The third punched board with the following and the fourth punched board with the center of the teeth shown in (d4) of FIG. 4(d) being the punching center line (A) are arranged alternately. Then, the third layer is again the first and second punching (a4), (b4), and the group of punching (a4)t (b4) and punching (C4),
The groups (d4) are stacked alternately. The positions of the dovetail keyways (■) of the first to fourth punching boards (a,) to (d4) are provided so that the two keyways are symmetrical with respect to the punching center line (A), Cutting center line (A)
The angle from is 1/2Dp, which corresponds to half of the key pitch angle (Dp).

By the way, in this case, both ends of the fourth punched board (d4) are cut at an angle deviated from the slot center line (B) by 1/4 of the slot pitch (Sp), that is, at the teeth ■ part deviated by 1/4 Sp. Therefore, the width of the teeth at both ends becomes extremely narrow. Such thin teeth are mechanically weak, and if stacked in this state, magnetic vibrations of the teeth will occur during operation, leading to deformation of the core shape or, in the worst case, the risk of dielectric breakdown of the stator coil. There is also. Therefore, it is difficult to adopt core punching in which the number of slots per sector is n+1/2 except when the tooth width is extremely wide compared to the slot width.

[Purpose of the invention]

An object of the present invention is to provide a stator core for a rotating electrical machine in which the number of slots per sector is n+1/2, without weakening the strength of the punched end teeth, regardless of the width of the punched teeth. be.

[Summary of the invention]

In the present invention, the number of slots per sector is n+1.
/2 (n is any integer) in the stator core of a rotating electrical machine, the dovetail keyway position is asymmetrical with respect to the center of the core punching, and the position of the dovetail keyway is asymmetrical with respect to the center of the core punching, and a fan-shaped Dovetail keyway position during punching to 1/4
It is characterized by alternately stacking one or more punched sheets with shifted slot pitches, and by using the center of the teeth and the center of the slot as the seam of the punched sheets,
A highly reliable stator core that does not weaken the strength of the punched end teeth.

[Embodiments of the invention]

Example 1 Below, regarding the first example of the present invention, Fig. 1(a) to
This will be explained with reference to (d).

The punching of the first layer of stator cores to be laminated is referred to as the first and second punchings (al) and (bl) shown in FIGS. 1(a) and (b). The plate (al) and the second punched board (bl) are made at an angle 1/asp corresponding to 1/8 slot pitch with respect to the center line of the punched board (A), counterclockwise when looking at the dovetail keyway ■ from above. direction.

On the other hand, the third punched board (C1) and the fourth punched board (dl) stacked on the second layer have the slot positions in the fan-shaped punched boards (c, ) the same as (al), (dl) is (b
Same as l), but the position of the dovetail keyway ■ is punched (a,).

Contrary to (bl), it is shifted clockwise by an angle of 1/8 Sp with respect to the punching center line when viewed from above. That is, the third
The fourth group of blanks (C1) and (dt) are the first. 1/4 for the second group of blanks (axL (bl))
Dovetail key by an angle corresponding to the slot pitch
The position of 〇 is shifted, so the dovetail keyway■
The slot position relative to the first. Second punching (a process L (
A third layer is placed in the same layer without changing the layer in the second group. The fourth blanks (C1) and (di) are arranged alternately.

In Figure 1, punching (al) = (bl) - (ax) -
(dl) was treated as a different type in consideration of press punching during sheet cutting, but (cl) was turned over (bl), and (d
1) may be used as the reverse of (&1). Alternatively, a plurality of sheets may be alternately laminated.

Next, the effect will be explained.

According to this embodiment 1, the number of slots per sector is n+1/2 because the dovetail keyway position is shifted.
Even in core punching, both ends of the punched core can be set at the center of the slot (2) or the center of the tooth (2). Therefore, after the core is laminated, the thin teeth at the punched sector joints are eliminated, so the magnetic vibration of the core teeth at the sector joints is eliminated, and the reliability of the rotating electric machine is improved.

Example 2 FIG. 2 shows a second example, in which the position of the dovetail keyway (■) is symmetrical with respect to the punching center line (A).
．． The position of the second punching Can), (b2) group and the dovetail keyway ■ is 1 with respect to the punching center line (A).
/4 slot pitch shifted by an angle corresponding to the third slot pitch.
The fourth punching group (C1) and (d8) were used.

Even in this case, both ends of all the punched plates can be placed at the center of the slot (2) or the center of the tooth (2), and the same effect as in the first embodiment can be obtained.

〔Effect of the invention〕

As explained above, according to the present invention, both ends of the core punched are always at the center of the slot or the center of the teeth.
The strength of the stator core itself and after lamination is increased, improving reliability and reducing the number of slots per sector to n.
Since +1/2 can be selected, the degree of freedom in design is increased, and the rotating electric machine can be designed more compactly, which has great effects.

[Brief explanation of drawings]

FIGS. 1(a) to d) and FIGS. 2(a) to d) are top views showing different embodiments of the stator core of a rotating electrical machine of the present invention, and FIG. 3 is a top view of the stator FIGS. 4(a) to 4(d) are cross-sectional views of essential parts showing the laminated structure of the iron core, and are top views showing the punching of a conventional iron core with the number of slots per sector being n+1/2.

Claims (1)

[Claims] In the stator core of a rotating electrical machine where the number of slots per sector is n+1/2 (n is an arbitrary integer), the dovetail keyway position is asymmetric with respect to the center of the core punching board, and the slots adjacent in the stacking direction are A stator core for a rotating electric machine, characterized in that one or more punched plates are alternately stacked with the dovetail keyway position shifted by 1/4 slot pitch in fan-shaped punched plates.