JPH0378447A - Stator core for linear motor - Google Patents

Abstract

PURPOSE:To reduce vibration and noise due to magnetic attraction by laminating punched core sections, while shifting slightly in the direction of lamination, such that a stair type cross section is provided at the butting section. CONSTITUTION:Five types of core boards 6-10 punched from an electromagnetic steel plate are laminated, while shifting the cutting position slightly at the yoke section, such that a stair type end section is provided. The core components are butted and jointed to construct a stator core, where the position of a gap 5 to be formed at the butting section is shifted layer by layer in the cross section at the yoke section. Flux in the punched core board 6a does not flow through the gap 5, as shown by arrows, but passes through the punched core boards 7, 10 laminated vertically and returns to the original layer, i.e., a punched core board 6b. Since the flux does not flows through the gap, no magnetic pole is produced. Consequently, inter-pole magnetic attraction is not produced and thereby vibration and noise can be suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to the structure of a linear motor stator core such as a linear motor, linear actuator, electromagnetic pump, etc.

(Prior art) The stator core of a motor, which is made of a thin plate-like magnetic material such as an electromagnetic steel sheet, is combined with a coil to form an armature or an induction motor core. ■
There are two methods: iron core assembly, ■coil insertion, or ■coil assembly, ■iron core insertion. Generally, the former method is used, but in the case of linear motors such as high-voltage machines where it is particularly desirable to assemble the coil first, the latter method may be used.

FIG. 7 shows the stator core of a split-core linear motor. In this case, the stator core is made of core punched cores 11 that are cut and divided into slots, and are laminated as shown in FIG. They are assembled by sequentially butting each other at the yoke portion 11b so that the two parts are assembled.

(Problem to be solved by the invention) However, the yoke part 1 where the partial cores are butted against each other
1b, it is unavoidable that a slight air gap 13 is formed as shown in Fig. 9. Therefore, when the iron core is magnetized in the direction of the arrow shown in Fig. 9, a magnetic attraction force is generated in this part, causing vibration and noise. It will happen.

The present invention has been made in view of the problems of the conventional stator core, and an object of the present invention is to provide a stator core for a linear motor that can reduce vibration and noise caused by magnetic attraction.

[Structure of the invention]

(Means for solving the problem) In order to reduce the above problem, that is, the generation of magnetic attraction force, it is sufficient to eliminate the magnetic poles that are generated when magnetic flux flows into the gap in the core abutting portion. For this reason, in the present invention, as shown in FIG. 1, the core punched plates 4 to 4 that are laminated to form a partial core are laminated with slight shifts in the lamination direction, so that the cross-sectional shape of the abutting portion becomes step-like. Configure. That is, the core punched parts 4 with different cutting positions are stacked as shown in FIG. 2, and are butted and joined together as a partial core to form the stator core.

(Function) Since the present invention is configured as described above, the magnetic flux flowing through the core punched core 1 in FIG. S Ishi 41 flows. As a result, no magnetic attraction force is generated between the abutted iron core extraction teeth, for example, 1 and 1, 2 and 2, etc., and therefore vibration and noise can be reduced.

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 3 shows a partial core constituting the core of this embodiment. There are five types of core punched plates 6 to 10, which are formed by punching and forming electromagnetic steel sheets, in which the cutting positions are slightly shifted at the yoke part, and when these are stacked, the ends have a stepped shape.

These partial cores are abutted and joined at the yoke part as shown in Fig. 4 to form one stator core, but at this time, the cross section of the yoke part is as shown in Fig. The positions of the voids 5 formed in the layers are shifted for each layer.

Figure 5 shows a partially enlarged view of the core joint area. The magnetic flux flowing through the core punched 6a does not pass through the air gap 5, as shown by the arrow in the figure, but passes through the core punches 7 and 10 stacked one above the other, and then returns to the original core punched layer. The flow returns to plate 6b.

When magnetic flux flows from a magnetic material such as an iron core to a non-magnetic material such as air, a magnetic pole is generated on the non-magnetic material side of the magnetic material, but when the magnetic flux does not flow through an air gap as in this example, a magnetic pole is generated. does not occur. Therefore, there is no magnetic attraction between the magnetic poles.

A stator core that generates less vibration and noise was obtained.

As another embodiment, instead of configuring the partial cores constituting the stator core in a step-like manner for each layer as in the previous embodiment, as shown in FIG. You can also use it as At this time.

This has the advantage that the joining work between the partial cores can be performed more easily.

〔Effect of the invention〕

As described above, in a linear motor stator core made up of partial cores divided into segments, the core punches that make up the partial core are stacked in a stepped manner at the yoke portion.

The air gap that occurs at the connection between the partial cores is dispersed in each layer, and the magnetic flux flows across the stacked core punches in this area and does not pass through the air gap, and as a result, no magnetic attraction is generated at the connection. Therefore, it is possible to obtain an anticonstant iron core with low vibration and noise.

[Brief explanation of drawings]

FIG. 1 is an enlarged partial cross-sectional view of the stator core of the present invention, FIG. 2 is a front view of the partial core in FIG. 1, FIG. 3 is an external view of the partial core according to an embodiment of the present invention, and FIG. The figure is a front view of the stator core in Figure 3, Figure 5 is an explanatory diagram of the flow of magnetic flux, and Figure 6 is a front view of the stator core in Figure 3.
The figure is an external view of a partial core in another embodiment, FIG. 7 is a front view of a conventional stator core, FIG. 8 is an external view of the partial core in FIG. 7, and FIG. 9 is a cross-section of the core in FIG. 7. It is an enlarged view of a part. 1.2, 3, 4, 6, 7, 8, 9, 10... Core punched 11a... Core punched tooth portion 11b... Core punched yoke portion 5... Gap portion Fig. 1 Fig. 111222 Fig.

Claims (1)

[Claims] In a stator core for a linear motor, the stator core for a linear motor is formed by integrating a plurality of partial cores in which core blanks are laminated and divided into segments by joining each other to other partial cores at their yoke portions, the joints forming the partial core. A stator core for a linear motor, characterized in that core punched plates are butted together at positions shifted by a slight length in the stacking direction.