JP2845941B2 - Electric stator - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric stator, and more particularly, to an electric stator suitable for improving reliability by minimizing magnetic flux leakage from a connecting portion of a teeth portion. .

[Conventional technology]

There are many cases where the coil is inserted from the outer periphery of the tooth toward the center. For example, as shown in Japanese Utility Model Publication No. 62-16746, the teeth are inserted as toroidal coils, and the rotor sides of the teeth are connected to each other and have relatively small power. It is not enough for a class whose rated output exceeds about 50W to obtain enough power to drive the compressor. Japanese Patent Application Laid-Open No. 63-174531 (Prior Art 2) is an example of a conventional technique for teeth. In this prior art, a notch is provided in a connecting portion of the teeth portion to prevent magnetic flux leakage from the connecting portion. Furthermore, Japanese Utility Model Application Laid-Open No. 61-62537 (Prior Art 3) discloses that by separating a connecting portion of a tooth portion,
A technique for preventing magnetic flux leakage from a connecting portion is disclosed.

[Problems to be solved by the invention]

The above-mentioned prior art has a problem that magnetic flux leaks from a connection portion on the inner diameter side (rotor side) of a tooth portion necessary for obtaining torque. Further, in the prior arts 2 and 3, the magnetic flux leakage from the connecting portion is solved, but the notch or the separating portion becomes a transition portion of the magnetic flux end to the rotor side, pulsating torque is generated in the rotor, and the vibration of the motor is reduced. It was the cause. In order to suppress this vibration, it is good to increase the rigidity of the teeth portion by increasing the connection portion that is weak in strength, but it is preferable to make the connection portion thinner for the reason of suppressing magnetic flux leakage. In the above-mentioned prior art, no consideration has been given to the problem that the vibration increases even though the magnetic flux leakage can be suppressed.

An object of the present invention is to provide an electric stator that prevents magnetic flux leakage without lowering the strength of a connecting portion of a tooth portion.

[Means for solving the problem]

The object is to use a plurality of teeth and a yoke formed by punching out a magnetic steel sheet, and a coil inserted into a slot formed by coupling the teeth and the yoke. In the electric stator in which the magnetic path is formed by the coupling between the teeth and the yoke, the radially inner connecting portion between the plurality of teeth is achieved by the central portion being distorted by the forcible pressing force.

[Action]

Since the divided teeth are connected on the side forming the inner diameter, the teeth have a substantially gear shape, and have an opening on the outer periphery. Therefore, the opening can be easily widened, and the coil winding can be inserted therefrom. As a result, the coil can be easily inserted, and the risk of damaging the coil coating is drastically reduced, so that the reliability can be improved.

〔Example〕

 Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a front view of an electric stator according to the present invention,
One part is a sectional view so that the inside of the slot can be seen. Reference numeral 1 denotes a yoke portion, 2 denotes a teeth portion, and 3 denotes a cross section of the coil wound in the slot. 4 is a coil end. FIG. 2 shows a state in which the teeth portion has been punched by a press die. Teeth part 2
Are connected to each other on the inner diameter side by a connecting portion 6, and the central portion 5 has a required minimum width determined by both the mechanical strength and the amount of magnetic path. In this manner, a substantially "gear-like" shape is formed, and the opening on the outer peripheral side can be widened, so that the coil insertion resistance when the coil winding is inserted therefrom is reduced, and the work becomes easy. Also, the occurrence of scratches and indentations on the coil coating can be significantly reduced.

However, while the connecting portion 6 maintains the mechanical strength, magnetically, the magnetic flux generated by the stator must be transmitted to the rotor side (not shown) through the teeth portion 2. Since a so-called magnetic path is generated and reduced, motor characteristics are deteriorated. This magnetic path is greatly influenced by the width of the connection center part 5, resulting in an increase in current, an increase in input, and a decrease in torque. As a remedy for this, it is necessary to increase the magnetic resistance without impairing the mechanical strength. This will be described with reference to FIGS. 3 and 4. FIG. 3 shows a structure in which a portion 5a having increased magnetic resistance is provided near the central portion 5 of the connecting portion. As a reference example of the means, a part of the connection part is cut out, or a part of the connection part is separated, but in this reference example,
The notch or the separated portion serves as a portion where no magnetic flux is supplied to the rotor side, and a pulsating torque is generated in the rotor, causing vibration of the motor.

The streaks indicated by 7 in FIG. 4 are formed by applying a machining strain by forcibly applying a pressing force in a streak shape or by applying a cut. In any case, it is possible to select either a method that is provided in a step before the coil winding introduction described later or a method that is provided in a later step,
The size is determined in consideration of the size of the magnetic path, the size of the shape, and the like. For example, calculating one example, in a single-phase induction motor with a rated output of 100 W, the minimum width of the connecting portion 5 is set to 1.0 mm.
When there is a magnetic load that allows about 14% of the magnetic flux passing through the teeth 2 to pass, the effective width can be considered to be about 1/2 or less when the method of leaving the punching distortion is used. The path amount is also halved (= 7% or less), and the influence on the entire magnetic loading is small, and the increase in current is only 1 to 2%. It is natural that the effective width can be further reduced by providing a streak portion formed by applying a streak-like press to the punching distortion portion.

FIG. 5 is a view showing a state after the coil winding is inserted.
Indicates a cross section of the coil, and 4 indicates a coil end. FIG. 6 is a partially enlarged view showing an insulating structure in the slot, 3 is a coil cross section, 8 is a slot insulating film, and 9 is a wedge. After the coil windings are housed in this way, the yoke 1 is joined to form a magnetic path, as shown in FIG.

FIG. 7 shows a case where the magnetic path is completely separated as a means for more effectively holding down the magnetic path after the yoke part 1 is connected. When the teeth portion 2 is joined and firmly fitted to the yoke portion 1, in a relatively small output model having a sufficient strength without having to connect the teeth portion 2 itself with the inner diameter portion anymore, It is one that has been separated using a cutting tool or the like.
In order to reduce the generation of chips that affect the coil and the like, a small gap is provided. Naturally, when a gap, that is, an air layer is provided, a remarkably large magnetic resistance is obtained, and a value of about 0.5 is sufficiently effective as compared with a mechanically strained one. It is well known that the smaller the gap, the smaller the Carter coefficient and the smaller the effective air gap between the rotor and the rotor, thereby improving the efficiency of the motor. However, as in the conventional case, when the coil is inserted from the inner peripheral side, it is inevitably 2 to 2.3 m depending on the wire diameter of the coil plus the occupation of the insertion jig.
m, and was forced to be about 3 to 7 times wider than the wire diameter. This eliminates the need to pass the coil, and results in a gap equal to or less than the wire diameter, so that the effect is large.

FIG. 8 shows an example in which the gap and a part of the slot are fixed with an adhesive non-magnetic material after separation.
Is an adhesive non-magnetic material such as an epoxy-based, silicon-based, or acrylic-based material. Since these penetrate and penetrate into the gap and the inside of the slot near the gap, the insulating material, the coil winding, and the like, the teeth portion 2 is firmly fixed, and is constantly subjected to microvibration by electromagnetic vibration or mechanical vibration. It also has the effect of protecting the insulating material and coil coating material. As a result, an excellent effect of preventing vibration noise and improving insulation reliability is obtained.

〔The invention's effect〕

According to the present invention, since the coil winding can be inserted from the outer peripheral side of the teeth portion and the opening, the coil insertion force is reduced.
It can be reduced to 1/5 or less compared to the conventional insertion through the inner diameter opening (not shown). Therefore, the defect rate due to the generation of scratches and indentations on the coil coating is reduced to 1/10 or less. Become.

In addition, the magnetic path of the inner diameter portion of the teeth portion, which is a factor of deteriorating characteristics due to this structure, can be suppressed to almost negligible level by means such as a method of increasing magnetic resistance and separation processing of the connection portion. The electrical machine manufacturing process of the electric stator can be automated, and excellent effects can be obtained, such as significantly reducing the occurrence of defects and obtaining high reliability.

Further, when the electric stator according to the present invention is used for an electric element having a cantilever bearing structure, for example, a hermetic electric compressor (not shown), the inner diameter of the stator is continuous, so that an air gap between the rotor and the rotor is provided. In the adjustment, the gap jig and the gap measuring jig can be used extremely smoothly, and the number of assembling steps can be reduced. Further, since the generation of harmonic components due to the slot ripple is eliminated, an excellent effect of reducing noise and vibration can be obtained.

[Brief description of the drawings]

 1 is a front view of an electric stator of the present invention, FIG. 2 is a partial explanatory view of the present invention, FIGS. 3 and 4 are enlarged partial explanatory views, and FIG. 5 is a coil winding of the electric stator. FIG. 6 is an enlarged view of the inside of the slot, and FIGS. 7 and 8 are enlarged views of the inside of the slot. DESCRIPTION OF SYMBOLS 1 ... Yoke part, 2 ... Teeth part 3 ... Coil cross section 4 ... Coil end, 5 ... Continuous central part 5a ... Magnetic resistance increasing part, 6 ... Connecting part 7 ... Streak, 10 ... Separation part 11: Adhesive non-magnetic material

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-2-211027 (JP, A) JP-A-63-224637 (JP, A) JP-A-2-131338 (JP, A) JP-A-2- 280641 (JP, A) Fully open sho 59-161361 (JP, U) (58) Field surveyed (Int. Cl. ⁶ , DB name) H02K 1/00-1/34

Claims (1)

(57) [Claims] And a coil inserted into a slot formed by coupling the teeth and the yoke using a plurality of teeth and a yoke formed by stamping a magnetic steel sheet. In the electric stator in which the magnetic path is formed by the connection of the portion and the yoke portion, the inner diameter side connection portion between the plurality of teeth portions is distorted at the center portion by the forcible pressing force. Electric stator.