JPH04208040A - Stator for alternator - Google Patents

Abstract

PURPOSE:To prevent production of noise from the stator or magnetic sound and to suppress noise at the time of operation of an alternator by placing an insulating sheet composed of damping material between the inner wall of each slot and each stator coil. CONSTITUTION:An insulating sheet 7 is bent in U-shape and placed while opening toward the opening 6a of a slot 6. A copper stator coil 8 is wound around a stator core 5. Consequently, a plurality of stator coils 8 are stacked in the insulating sheet 7 of each slot 6. The damping insulating sheet 7, placed between the stator coil 8 and the stator core 5, provides a damping system comprising a spring 9 and a damper 10 and damps the vibration F0 of the stator coil 8 during operation of an alternator. It is then transmitted as vibration F1(<F0) of the stator core 5 thus suppressing noise.

Description

[Detailed description of the invention] [Industrial application field] This invention relates to a stator for an alternator.

[Conventional technology]

Conventionally, the stator in an alternating current generator has a large number of stator coils stacked in each slot of the stator core with an insulating sheet (for example, two sheets of polyamide paper bonded with synthetic resin) interposed therebetween. It is wrapped in

[Problem to be solved by the invention]

However, when the stator coil vibrates during the operation of the generator, the stator core also vibrates, producing unpleasant noises and magnetic noise.

SUMMARY OF THE INVENTION An object of the present invention is to provide a stator for an alternator that can prevent the generation of abnormal noises and magnetic noise from the stator and reduce noise during operation of the generator.

[Failure to solve the problem]

The present invention includes a plurality of slots formed on the inner circumferential surface of a stator core, a stator coil wound around the stator core, and a portion of which is overlapped in a large number within each slot;
The gist of the present invention is a stator for an alternator, which includes an insulating sheet made of a damping insulating material and interposed between the inner wall of the slot and each stator coil.

[Effect]

The vibrations of the stator coil caused by the operation of the generator are attenuated by an insulating sheet made of a damping insulating material and transmitted to the stator core, thereby preventing the occurrence of abnormal noise or magnetic noise.

〔Example〕

An embodiment embodying the present invention will be described below with reference to the drawings.

FIG. 2 shows a sectional view of the alternator, and FIG. 3 shows a side sectional view of the stator. As shown in these figures, a rotor 2 is rotatably supported within the generator by a bearing 1, a field coil 3 is wound around the rotor 2, and a cooling fan 4 is provided. ing. An annular stator core 5 is disposed around the rotor 2 so as to surround the rotor 2, and a large number of slots 6 are provided on the entire inner peripheral surface of the stator core 5 in the front-rear direction (see Fig. 2). It is recessed in the left-right direction).

FIG. 1 is a front view showing details of the slot 6, and FIG. 4 is a perspective view showing an insulating sheet 7 disposed within the slot 6. As shown in these figures, the insulation sheet 7 has a thickness of 0.8
Made of ma silicone rubber, silicone rubber is heat resistant,
In addition to insulating properties, it also has vibration damping properties. The insulating sheet 7 is bent into a U-shape. On the other hand, the slot 6 of the stator core 5 is formed such that the width of the opening 6a is narrow, and the insulating sheet 7 or the opening 6 of the slot 6 is formed in the slot 6.
It is disposed in an open state toward the a side.

Further, a stator coil 8 made of copper is wound around the stator core 5. As a result, a large number of stator coils 8 are arranged in the insulating sheet 7 of each slot 6 in a stacked state.

In this way, the stator core 5, the insulating sheet 7, and the stator coil 8 constitute the stator of this embodiment.

Noise levels were measured for a generator equipped with this stator and an alternator equipped with a conventional stator (two sheets of polyamide paper bonded together using a synthetic resin as an insulating sheet). The results are shown in FIG. 5, in which the conventional generator is shown by a broken line, and the generator of the embodiment is shown by a solid line. From the figure, it can be seen that the noise level of the generator of the example is reduced.

This noise reduction effect is due to the following reasons.

In the conventional stator, as shown in FIG.
Since the insulating sheet S having no vibration damping properties was interposed between the stator coil 8 and the stator coil 8, the structure was a rigid direct connection structure. That is, the vibration FO generated in the stator coil 8 was directly transmitted to the stator core 5 as vibration F1 (=FO).

However, in this embodiment, as shown in FIG. 7, an insulating sheet 7 with vibration damping properties is interposed between the stator coil 8 and the stator core 5, so that the spring 9 and the damper 10 are It has a damping system structure. Therefore, after the vibration FO of the stator coil 8 is attenuated, the vibration Fl of the stator core 5 is reduced.
(<FO), and the noise is reduced.

In this way, in the stator of the alternator of this example,
Since the insulating sheet 7 made of a damping insulating material (silicon rubber) is interposed between the inner wall of the slot 6 and each stator coil 8, the vibration of the stator coil 8 caused by the operation of the generator is absorbed by the insulating sheet 7. is attenuated by and transmitted to the stator core 5,
Abnormal noises and magnetic noises are prevented from occurring. Therefore, noise during operation of the generator can be reduced.

〔Effect of the invention〕

As detailed above, according to the present invention, it is possible to prevent the generation of abnormal noise and magnetic noise from the stator, and to achieve the excellent effect of reducing noise during operation of the generator.

[Brief explanation of the drawing]

Fig. 1 is a front view showing details of the inside of the slot in the stator of the embodiment, Fig. 2 is a sectional view of the alternator, Fig. 3 is a front view of the stator, and Fig. 4 is a perspective view of the insulating sheet. Fig. 5 is a diagram showing the noise level of an alternator equipped with the stator of the example and the conventional stator, Fig. 6 is a diagram showing a vibration transmission model in the conventional stator, and Fig. 7 is a diagram showing the actual stator. FIG. 3 is a diagram showing a vibration transmission model in an example stator. 5 is a stator core, 6 is a slot, 7 is an insulating sheet, and 8 is a stator coil. Patent applicant Nippondenso Co., Ltd. Agent Patent attorney On 1) Hironobu (and 1 other person) Figure 4 Figure 1 Figure 5 Alternator ω rotation (rpm)

Claims (1)

[Scope of Claims] 1. A plurality of slots formed on the inner circumferential surface of the stator core, and a fixing member wound around the stator core, a portion of which is overlapped in multiple slots within each of the slots. A stator for an alternator, comprising a child coil and an insulating sheet made of a damping insulating material and interposed between the inner wall of the slot and each stator coil.