JPH05300684A - Stator of motor - Google Patents

Abstract

PURPOSE:To provide a stator for a motor equipped with an inexpensive protective means capable of surely and easily protecting the coil end of exciting winding. CONSTITUTION:This stator is equipped with a roughly cylindrical stator core 12, which is arranged outside of a motor and has a plurality of slots 10 extending in axial direction at the inside periphery, a plurality of exciting windings 16, which are accommodated in each slot 10 and have coil ends 14 projecting outward from the end face 12a of the stator core 12, and a cloth tape 18, which covers and protects the coil end 14 of each exciting winding 16. The cloth tape 18 is made of fibers having electric insulation property and is excellent in heat resistance, and is wound in the shape of a bandage continuously on time whole of a plurality of complicated coil ends 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stator of an electric motor, and more particularly to improvement of a stator of an electric motor provided with a protection means for protecting a coil end portion of an exciting winding projecting outward from an end surface of a stator core.

[0002]

2. Description of the Related Art An excitation winding wound around a stator of an electric motor forms a coil and is accommodated in a slot of a stator core. Therefore, a coil end portion protruding outward from both end surfaces of the stator core is inevitably formed. Form. Therefore, when the stator is fixed to the housing of the electric motor, the coil end portion of the excitation winding is exposed in the space inside the housing. Further, in the coil end portion of the excitation winding, a plurality of windings of different phases are intricately arranged so as to be close to or in contact with each other. Therefore, if the insulating coating previously applied to the windings is damaged, the windings or the housings There is a fear that a short circuit easily occurs with another conductive member such as, and the operation of the electric motor is disturbed.
Such a problem becomes remarkable especially in the case of an electric motor used in an inferior environment, such as a so-called built-in motor directly incorporated in the spindle of a machine tool. In a built-in motor, the coil ends of the excitation winding that project outward from both end faces of the stator core are easily exposed to the chips generated from the workpiece, so the chips adhering to the coil ends are insulated from the winding. There is a great risk of damaging the coating. It is also conceivable that the insulating coating of the winding or the winding itself may be damaged due to the carelessness of the operator such as colliding the coil end portion with another member during the assembling work on the main shaft. In order to solve such a problem, conventionally, the coil end portions projecting from both end surfaces of the stator core are covered with a heat-resistant resin material, and the coil ends are prevented from adhering flying chips or colliding with other members. It is known how to protect parts.

[0003]

A method of protecting a coil end portion with a heat-resistant resin material is to put a stator core around which an excitation winding is wound in a predetermined mold and inject a molten resin material into the coil end portion to cure it. Therefore, it is possible to reliably cover and protect the coil end portion where many windings are intricate. However, since such a resin molding process generally consumes a long time including the time required for curing, there has been a problem that the production cost per unit time of the electric motor increases together with the increase of the material cost. In addition, there is a fear that the winding at the coil end may be damaged due to the curing shrinkage of the resin material.

The present invention has been devised and devised to solve these problems, and its purpose is to reliably and easily protect the coil end portions of the excitation winding protruding from both end surfaces of the stator core. An object of the present invention is to provide a stator of an electric motor that includes a protection means that can be installed at low cost and that can reduce the production cost of the electric motor.

[0005]

In order to achieve the above object, a stator of an electric motor provided by the present invention has a substantially cylindrical stator core having a plurality of slots extending in the axial direction at its peripheral portion, and each of the slots. A plurality of excitation windings that are housed in the stator core and have a coil end portion that projects outward from the end surface of the stator core and that is wound around the stator core; and a protection means that covers and protects the coil end portion of the excitation winding. In a stator of an electric motor, the protection means is formed of a fiber having electrical insulation and excellent heat resistance, and is wound around the coil end portions of the plurality of excitation windings to cover substantially the entire surface of the coil end portion. It is characterized by comprising a woven tape for coating.

[0006]

When a textile tape formed of fibers having electrical insulation and excellent heat resistance is wound around the coil end portions of a plurality of exciting windings, the textile tape becomes a plurality of coils that are intricate and close to each other. The complicated arrangement of the end portions can be easily followed, and the substantially entire surfaces of the plurality of coil end portions can be surely covered in a bandage shape. Therefore, the coil end portion is protected by the woven tape from adhering chips and the like and colliding with other members.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in more detail based on its embodiments with reference to the accompanying drawings. FIG. 1 is a partial perspective view of a stator having a coil end protecting means according to an embodiment of the present invention, FIG. 2 is a plan view showing a procedure for mounting the coil end protecting means, and FIG. 3 is a coil end. FIG. 3 is a partial perspective view of the stator of FIG. 1 before the protection means is attached to the portion.

Referring to FIG. 1, a stator of an electric motor according to an embodiment of the present invention includes a substantially cylindrical stator core 12 which is disposed on the outer peripheral side of the electric motor and has a plurality of axially extending slots 10 on its inner peripheral portion. , A coil end portion 14 housed in each slot 10 and protruding outward in the axial direction from an end surface 12a (only one end surface is shown) of the stator core 12
A plurality of excitation windings 16 (see FIG. 3) and a protection means 18 for covering and protecting the coil end portion 14 (see FIG. 3) of each excitation winding 16 are provided.

The stator core 12 is formed by stacking magnetic steel plates in the axial direction, and the plurality of slots 10 formed in the inner peripheral portion at equal intervals in the circumferential direction are continuous in the axial direction by this stacking. The excitation winding 16 is wound in each slot 10 in a coil shape according to a predetermined rule as shown in FIG. The excitation winding 16 of the stator according to this embodiment has a winding configuration of lap winding and double layer winding as shown in the figure. Therefore, the coil end portions 14 of the respective excitation windings 16 are arranged outside the end surface 12a of the stator core 12 so as to be intricately in contact with each other as shown in the drawing.

When the stator is used as, for example, a stator of a built-in motor directly mounted on the main shaft of a machine tool, the coil end portion 14 thus arranged in a complicated manner is exposed to the chips scattered from the workpiece. Therefore, the chips adhering to the mutual contact portions may damage the insulating coating previously applied to the excitation winding 16, thereby causing a short circuit between the different-phase windings. Therefore, the stator according to this embodiment includes the fabric tape 18 wound around the entire plurality of coil end portions 14 as a protection means for covering and protecting the coil end portions 14, as shown in FIG.

The woven tape 18 is made of fibers having electrical insulation and excellent heat resistance. During operation of the electric motor, the coil end portion 14 of the stator is generally 150 ° C.
It is essential that the woven tape 18 be made of a material that can withstand the high temperatures, since it reaches high temperatures above. Further, it is also necessary to have general physical properties as a woven fabric so that the plurality of complex coil end portions 14 can be continuously wound in a bandage shape. A suitable material for such a woven tape 18 is "Conex" (trade name) made of aromatic polyamide fiber. However, other synthetic fibers such as synthetic fibers and natural fibers can be used as long as they satisfy the above conditions.

As shown in FIG. 2, the fabric tape 18 is wound in multiple layers so as to cover substantially the entire surfaces of the plurality of coil end portions 14. The winding procedure is arbitrary, but it is desirable to wind the coil end portion 14 so that the exposed portion of the coil end portion 14 is as small as possible. Both ends of the woven tape 18 that has been wound are temporarily fixed by being sandwiched between the tapes or by being fastened to each other. In this way, after covering substantially the entire surface of the coil end portion 14 with the fabric tape 18, the entire stator is impregnated with an impregnating agent such as varnish and then cured, whereby the stator core 12, the excitation winding 16, and the fabric tape 18 are formed. , Securing themselves and each other. Due to the physical properties of the woven tape 18, the impregnating agent easily penetrates, which provides an additional effect of promoting fixation and protection of the coil end portion 14.

[0013]

As is apparent from the above description, according to the present invention, a plurality of exciting windings are wound around the stator core by the woven tape formed of the fiber having the electric insulation and the excellent heat resistance. Since the coil end portion of the wire is configured to be covered and protected, the woven tape can be easily wound around the entire plurality of coil end portions in a band-like shape, and the substantially entire surface can be surely covered. Therefore, the coil end portion of the excitation winding of the stator can be reliably and easily protected, and the working time for installing the protection means is significantly shortened, which contributes to the improvement of reliability while suppressing the production cost of the electric motor. Bring

[Brief description of drawings]

FIG. 1 is a partial perspective view of a stator of an electric motor including a coil end protection unit according to an exemplary embodiment of the present invention.

FIG. 2 is a plan view showing a procedure for mounting a protection unit on a coil end portion of the stator shown in FIG.

FIG. 3 is a partial perspective view of the stator shown in FIG. 1 before the protection means is attached to the coil end portion.

[Explanation of symbols]

 10 ... Slot 12 ... Stator core 14 ... Coil end part 16 ... Excitation winding 18 ... Woven tape

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuhisa Numai 3580 Koshinoba, Oshinomura, Minamitsuru-gun, Yamanashi Prefecture FANUC CORPORATION (72) Inventor Tomohiro Seki 3580, Koshiba, Oshinomura, Nantsuru-gun, Yamanashi Prefecture Address within FANUC CORPORATION

Claims (1)

[Claims] 1. A stator core having a substantially cylindrical shape having a plurality of slots extending in the axial direction at a peripheral portion, and a coil end portion housed in each of the slots and protruding outward from an end surface of the stator core. A stator of an electric motor comprising: a plurality of exciting windings wound around the stator core; and a protecting means for covering and protecting the coil end portion of the exciting winding, wherein the protecting means has electrical insulation and heat resistance. A stator of an electric motor, comprising a fabric tape which is formed of fibers having excellent properties and which is wound around the coil end portions of the plurality of excitation windings and covers substantially the entire surface of the coil end portions.