JPS6244040A - Electric motor - Google Patents

Abstract

PURPOSE:To prevent the torque pulsation and outbreak of noise by clamping the laminated layers of silicon steel plates with the end plate to cover the teeth completely. CONSTITUTION:The silicon steel plate 1 is laminated in multiple layers formed by punching the grooves where the winding is equipped. To the both end faces of the silicon steel plate 1 an end plate 2 is abutted and clamped with a bolt and nut 3 to fasten the laminated layers of the silicon steel plate 4. The end plate 2 used for this process is formed so that the trunk and teeth of the laminated layers of the silicon steel plate may be completely covered. Thus each silicon steel plate is never incompletely clamped and wound not open at the teeth. The outbreak of the flapping phenomenon is therefore prevented and that of the torque pulsation is effectively prevented as well.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electric motor. In particular, the present invention relates to improvements that prevent torque pulsation and noise generation in low-inertia electric motors, improve the mechanical strength of laminated iron cores, and reduce the number of man-hours in the manufacturing process.

[Conventional technology]

To manufacture M-layer cores for stators of electric motors, particularly jacketless electric motors, one of two approaches has been used. The first method, as shown in Fig. 2, is to stack silicon steel plates formed into a hollow disk shape into a hollow cylinder, and then weld the outer periphery of the silicon steel plates to interconnect the silicon steel plates to form a laminate. In Figure 0, 1 is a silicon steel plate, and 5 is a welding area. The second method is to stack silicon steel plates in a hollow cylindrical shape and then connect the silicon steel plates to each other using an adhesive to form a laminate.

[Intermediate point that the invention attempts to solve]

The conventional electric motor having the laminated core type stator having the above-described structure has the following drawbacks.

B. In a structure in which silicon steel plates are welded after forming M layers, it is difficult to avoid the occurrence and residual distortion due to welding, and as shown by the broken line 6 in FIG. 2 and the broken line 7 in FIG. A undulation occurs between welding areas, and due to these two reasons, torque pulsations are unavoidably accompanied.

B. In a structure in which silicon steel plates are connected using an adhesive to manufacture a silicon steel plate laminate, the adhesive hardens even in the grooves and fills the grooves, so the adhesive hardens in the grooves before winding. It is necessary to perform additional work to remove the adhesive that has been applied, and since the work of impregnating with insulating varnish is performed after winding, the work of impregnating the adhesive with the adhesive, the work of impregnating with the varnish, and the impregnating work are required twice. If the adhesive used is incorrectly selected, the mechanical strength may be insufficient.

Furthermore, in order to obtain a low-inertia electric motor, the inner diameter of the rotor must be made small, and the cross-sectional area of the magnetic flux is limited, so the depth of the grooves must be increased. When the depth of the groove is increased, the silicon steel plates rub against each other at the tooth portions, resulting in extremely large torque pulsations and increased noise. In short, even with any of the above structures, it is difficult to manufacture a low-inertia electric motor, especially the laminated core of its stator.

The purpose of the present invention is to eliminate this drawback, and in particular, to provide a laminated iron core that does not cause torque pulsation or noise, has high mechanical strength, and requires fewer man-hours to manufacture.
The object of the present invention is to provide an electric motor having a stator having such a laminated core.

[Means for solving problems]

The means taken by the present invention to achieve the above object is a laminated iron core, particularly a laminated iron core of a stator.

As shown in Fig. 1 (a) and Fig. 1 (b), silicon steel plates l are laminated, and two end plates 2 covering the - portion are brought into contact with the end faces of the silicon steel plates l. The structure is such that the silicon steel plates are fastened together using bolts 3 that pass through the 81-layer body.

[Effect]

The present invention focuses on the fact that the above-mentioned drawbacks are due to insufficient fastening of silicon steel plates, especially insufficient fastening at narrow tooth portions, and the present invention has developed an end plate that completely covers the tooth portions of silicon steel plates. aBy firmly tightening the carcass,
This prevents the silicon steel plate from waving, which causes torque pulsation, and prevents the generation of noise due to insufficient fastening.Furthermore, the manufacturing process is simplified by eliminating the adhesive impregnation process.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, with reference to the drawings, a manufacturing process of a stator for an electric motor according to an embodiment of the present invention will be explained to further clarify the structure and unique effects of the present invention.

1st (L) v4, 1st (b) Refer to Figure 1. A plurality of silicon steel plates l each having a punched groove into which a winding is inserted are laminated, an end plate 2 is brought into contact with both end surfaces of the silicon steel plate 1, and a bolt nut 3 is held. Tighten to fasten the silicon steel plate laminate 4. The end plate 2 used in this process is designed to sufficiently cover the trunk and tooth portions of the silicon steel plate laminate.
If necessary, the shape of this end plate 2 is made to be exactly the same as the shape of the silicon steel plate.

Therefore, each of the silicon steel plates l will not be insufficiently tightened, and will not open at the teeth, and will not cause the waving phenomenon of the silicon steel plates as shown by the broken line 6 in Fig. 2. The occurrence of torque pulsation is also effectively prevented.

〔Effect of the invention〕

As explained above, in the electric motor according to the present invention, the laminated core, particularly the laminated core of the stator, has silicon steel plates laminated, and two end plates covering the part marked with * are brought into contact with the end faces of the laminated core, and the laminated core of the stator is The present invention has a laminated core configured to fasten the silicon steel plates with bolts passing through the laminate and the laminate.

B. There is no risk of welding distortion, and there is no risk of waviness of the silicon steel plate. C. There is no risk of adhesive entering the groove, and the teeth will not open, making it mechanically stable. The strength is improved, and for these reasons, the occurrence of torque pulsation is prevented, and the generation of noise is prevented.Furthermore, since the impregnation process is only the insulating varnish impregnation process, there is no increase in the number of work hours, etc. have a profit of

[Brief explanation of the drawing]

FIG. 1(a) is a side view of a stator core of an electric motor according to an embodiment of the present invention. FIG. 1(b) is a sectional view taken along line AA of a stator core of a motor according to an embodiment of the present invention. FIG. 2 is a front view of a stator core of a motor according to the prior art. FIG. 3 is a side view of a stator core of a motor according to the prior art. i-...Silicon steel plate, 2...End plate, 3...Port, 4-Fist/aN iron core, 5◆--Welding area,
6...Silicon steel plate exhibiting a wavy shape.

Claims (1)

[Claims] A laminate of silicon steel plates (1) passes through two end plates (2) that are in contact with both end surfaces of the laminate, and the laminate and the end plates (2). An electric motor having a laminated core (4) fastened with bolts (3), characterized in that the end plate (2) also covers the teeth of the silicon steel plate (1).