JPH06327203A - Varnish impregnation method for electronic appliance - Google Patents

Abstract

PURPOSE:To prevent formation of an air gap when an insulating layer is formed of a varnish. CONSTITUTION:A stator 11 with a winding 13 provided on a stator iron core 12 is held by a chuck device 20. At that time, a bag 22 made of a rubber in the inner circumferential surface of the chuck device 20 adheres closely to the whole surface of the outer circumference of the stator iron core 12. The stator 11 is rotated and at the same time a very small amplitude of vibration is applied to the stator 11 by a vibrator 23 and at the same time a varnish V is dropped to the stator 11 from the dropping hole 21a of a varnish supplying nozzle 21. The winding 13 and the stator iron core 12 are entirely filled up with the varnish to be dropped, but since the outer circumferential surface of the stator iron core 12 is covered with the bag 22, the outflow of a varnish V is prevented. After that, electricity is applied to the winding 13 to heat the stator 11, thereby bringing the impregnated varnish V into a fixed gel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for impregnating varnish of electric equipment, which is an improved method of varnishing a winding body such as a stator of a rotary electric machine.

[0002]

2. Description of the Related Art In electrical equipment such as rotating electric machines, a stator having a winding wound around an iron core is impregnated with varnish to improve the insulation, heat resistance and strength of the stator. Is being done. Conventionally, as a varnish impregnation treatment method of this type, a dipping method of immersing the stator in a tank containing varnish and then pulling it up to heat-harden it, and a dropping impregnation method of dripping the varnish onto the stator to impregnate It is used.

A conventional varnish impregnation method by the dipping method will be described with reference to FIGS.
A stator 1 of a rotating electric machine is configured by winding a winding 4 around a stator core 3 formed by laminating thin steel plates 2 so as to be housed in an open slot 3a. At this time, as shown in FIG. 8, a U-shaped insulating paper 5 is provided on the inner surface of the slot 3a, and an insulating wedge 6 is provided at the opening of the slot 3a.

In carrying out the varnish impregnation treatment, FIG.
As shown in FIG. 5, the stator 1 is dipped in the tank 7 containing the varnish V, pulled up from the tank 7 and left to stand naturally to drop the excess varnish V, and then the stator 1 is housed in the heating furnace. The varnish V is cured by heating. As a result, the insulating layer 8 in which the impregnated varnish V is hardened is formed on the surfaces of the stator core 3 and the winding 4, between the wires 4a, between the winding 4 and the insulating paper 5, and the like. is there.

[0005]

However, in the above-mentioned conventional varnish impregnation method, in the step of dropping the excess varnish V or the step of heating and curing the varnish V, the varnish V once impregnated is, for example, a stator core. There is a problem that the thin steel plates 2 of No. 3 flow out due to a capillary phenomenon due to a capillary phenomenon, and as shown in FIG. 8, a gap S is formed between the inner surface of the slot 3a and the insulating paper 5. Moreover, as shown in FIG. 7, the end of the thin steel plate 2 that constitutes the stator core 3 is not punched straight, and is uneven due to the occurrence of so-called burr. Even if it seems to be doing, there is a slight gap left and the adhesion is poor, and this gap contributes to the outflow of the varnish V due to the capillary phenomenon.

[0006] As described above, when the void S is generated, the insulating property is deteriorated, and the thermal conductivity is lowered to deteriorate the heat dissipation effect. The generation of such voids S occurred in the same manner even in the dropping impregnation method.

The present invention has been made in view of the above circumstances, and an object thereof is to form an insulating layer of varnish.
Another object of the present invention is to provide a method for impregnating a varnish of an electric device, which can prevent the formation of voids as much as possible.

[0008]

A method for impregnating a varnish for an electric device according to the present invention is a method for impregnating a varnish into a winding body formed by winding a winding on an iron core. It is characterized in that the winding body is rotated around the axis of the winding member while the flexible contact member is in close contact with the varnish so as to be drip-impregnated.

In this case, it is more effective if the winding body is dipped and impregnated with varnish while applying minute vibration simultaneously with rotation. Further, the varnish may be dropped toward the coil end portion of the winding and the inner peripheral portion of the iron core. Further, after the varnish is dropped and impregnated, the winding body may be heated while the contact member is kept in contact.

[0010]

According to the method for impregnating varnish of electric equipment of the present invention,
Since the varnish is impregnated while the outer peripheral surface of the iron core is covered with a flexible adhesive member, the adhesive member prevents the flow of air between the inner and outer circumferences of the iron core and thus the outflow of varnish. Like Therefore, the varnish can be prevented from flowing out during the varnish impregnation treatment, and the formation of voids can be suppressed. Further, the varnish can be uniformly impregnated over the entire winding body by performing the drip impregnation treatment of the varnish while rotating the winding body.

In this case, if the winding body is dipped and impregnated with the varnish while applying a minute vibration simultaneously with the rotation, bubbles can be expelled by the vibration, and the varnish can be removed between the wires of the winding. It is possible to enter even narrow spaces such as. Further, by dripping the varnish toward the coil end portion of the winding and the inner peripheral portion of the iron core, the varnish can be effectively impregnated over the entire winding body. Further, if the winding body is heated while the outer peripheral surface of the iron core is covered with the contact member, the varnish can be prevented from flowing out at the time of heating.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a varnish impregnation process for a stator of a rotary electric machine will be described below with reference to FIGS. The present embodiment corresponds to claims 1 to 4. First, a schematic configuration of the stator 11 that is a winding body will be described. As shown in FIGS. 4 and 5, this stator 1
1 is constituted by winding a plurality of windings 13 around a stator core 12. The stator core 12 is formed by laminating a large number of ring-shaped thin steel plates, for example, and has a cylindrical shape as a whole. Further, as shown in FIG. 6, the stator core 12 is provided with a plurality of slots 12a for accommodating the windings 13 so as to open to the inner peripheral side.

On the other hand, as shown in FIG.
Is formed by winding a wire 14 such as a polyesterimide wire, and is housed in the slot 12a of the stator core 12. At this time, the U-shaped insulating paper 15 is provided on the inner surface of the slot 12a, and the winding 13
Are fixed by wedges 16. Further, as shown in FIG. 5, the coil end portion 13a of the winding wire 13 is shaped by a binding thread 17, and further, the coil end portion 13a is provided with a required connection between the winding wires 13 and is exposed. Line 18
(See FIG. 1) has been derived.

The stator 11 thus constructed is subjected to a varnish impregnation treatment as will be described later, and as a result, as shown in FIG.
As shown in FIG. 5, an insulating layer 19 made of varnish is formed on the surface of the winding wire 13, between the wires 16 of the winding wire 13, between the winding wire 13 and the insulating paper 17, and the like. As a result, the heat resistance strength and vibration resistance strength of the winding wire 13 can be improved, the fixing force to the stator core 12 can be strengthened, and the insulation effect can be improved.

Here, the impregnation treatment device used for the varnish impregnation treatment on the stator 11 will be briefly described.
As shown in FIG. 1 and FIG. 2, the impregnation treatment apparatus according to the present embodiment includes a chuck device 20 for supporting the stator 11,
A varnish supply nozzle 21 for dropping the varnish V is provided.

Of these, the chuck device 20 has a cylindrical shape with an open right side surface in FIG. 1, and the stator 11 (stator core 12) is inserted by inserting the stator 11 from the opening.
The outer peripheral surface of the is gripped and fixed. On the inner peripheral surface of the chuck device 20, a rubber bag 22 as a contact member having flexibility is provided in a ring shape. When air is supplied from the air supply port 22a, the bag 22 elastically swells and comes into close contact with the entire outer peripheral surface of the stator core 12 of the stator 11. The stator 11 is attached to the chuck device 2 through the bag 22.
It is grasped at 0.

The shaft portion 20a provided on the left side of the chuck device 20 in FIG. 1 is connected to a rotary drive mechanism such as a motor (not shown) so that the stator 11 can be held in a fixed state. It is adapted to be rotated around the axis of 11. The vibrator 2 that contacts the outer peripheral surface of the chuck device 20 is provided below the chuck device 20.
3 is provided, and the chuck device 20 is provided by the vibrator 23.
As a result, minute vibration is applied to the stator 11.

Further, in this embodiment, the chuck device 20 is used.
A pair of power supply rings 24, 24 for energizing the winding 13 are provided in a ring shape extending in the circumferential direction on the outer periphery of the power supply ring 24, 24.
5 and 25 are in contact with each other. During the varnish impregnation process, the lead wire 18 of the winding 13 is connected to the feeding ring 24, so that the winding 13 generates heat as it is energized. .

On the other hand, the tip end portion of the varnish supply nozzle 21 is arranged in the stator core 12 of the stator 11 through the hollow portion in the shaft portion 20a of the chuck device 20, and the tip portion thereof is provided. For example, 3 provided downward
The varnish V is adapted to be dropped from the individual dropping ports 21a. In the present embodiment, the varnish V is dripped from the two left and right drip openings 21a in the drawing to both coil end portions 13a, and from the middle drip openings 21a toward the inner peripheral portion of the stator core 12, V is dropped.

Next, the procedure of the varnish impregnation process for the stator 11 will be described. As described above, the stator 11 in which the winding 13 is wound around the stator core 12 has the structure shown in FIGS.
As shown in FIG. At this time, air is supplied to the rubber bag 22, and the stator 11 is gripped with the bag 22 being in close contact with the entire outer peripheral surface of the stator core 12. At this time, the lead wire 18 of the winding 13 is connected to the power feeding ring 24.

The varnish V is dripped and impregnated onto the stator 11 from the three drip openings 21a of the varnish supply nozzle 21, and at the same time, the chuck device 20 is rotated by the rotary drive mechanism. At the same time, the vibrator 23 gives a minute vibration to the chuck device 20. As a result, the varnish V is dripped while the stator 11 rotates about its axis and vibrates slightly in the radial direction. The varnish V that was dripped is the winding 13
It is filled in the surface of the whole stator 11, the space between the slots 12a and the winding 13, the space between the wires 14 of the winding 13, etc.

At this time, the outer peripheral surface of the stator core 12 is the bag 2
Since it is covered in close contact with the stator core 1,
In a slight gap between the thin steel plates constituting the stator 2,
The flow of air between the inner and outer peripheries of the stator is prevented, and thus the varnish V is prevented from flowing out from the outer peripheral surface of the stator core 12.

Further, since the varnish V is dropped while rotating the stator 11, the dropping position of the varnish V changes in the circumferential direction with time, and the varnish V is uniformly impregnated throughout the circumferential direction of the stator 11. be able to. Moreover,
Since the varnish V is made to drip from the three drip openings 21a toward the coil end portion 13a of the winding wire 13 and the inner peripheral portion of the stator core 12, the varnish V is evenly distributed in the axial direction of the stator 11. V can be impregnated.

Further, since the varnish V is drip-impregnated into the stator 11 at the same time as a minute vibration is given to the stator 11, the bubbles can be expelled by the vibration, and the varnish V can be the element of the winding 13. Thus, the wire 14 can enter even a narrow gap such as between the wires 14.

When the dropping of the varnish V is completed, the brushes 25 are energized with the stator 11 held by the chuck device 20. Then, the winding 13 is energized, and the heat generated by the winding 13 (Joule heat) causes
The entire stator 11 is heated. As a result, the varnish V impregnated in the stator 11 is heated and a certain degree of curing (gelation) is performed. In this case, the stator core 12
While the outer peripheral surface of the is covered with the rubber bag 22,
Since the varnish V is heat-cured, even if the viscosity of the varnish V temporarily decreases during heating, the varnish V can be gelled while preventing the varnish V from flowing out to the outer peripheral side, and the varnish V is once gelled. Then, there is no possibility that the varnish V will flow out to the outside.

Thereafter, the varnish V is gelled, and the stator 11 is housed in a heating and drying oven (not shown) and heated, so that the varnish V is completely cured and the insulating layer 19 is formed. is there. At this time, as described above, the varnish V is prevented from flowing out, and as shown in FIG. 3, not only between the wires 14 of the windings 13 but also between the inner surfaces of the slots 12a and the insulating paper 15. Even in the interval, the insulating layer 20 can be filled without forming voids.

As described above, according to the present embodiment, the varnish impregnation process is performed while the outer peripheral surface of the stator core 12 is tightly covered with the rubber bag 22, so that the varnish is prevented from flowing out. This can be prevented in advance, and formation of voids in the insulating layer 19 can be prevented as much as possible. As a result, the heat dissipation effect and heat resistance strength and vibration resistance strength of the stator 11 are improved, the fixing force of the winding wire 13 to the stator core 12 is strengthened, and insulation deterioration is prevented.

In particular, in this embodiment, the varnish V is drip-impregnated into the stator 11 while applying a minute vibration simultaneously with the rotation, so that the bubbles can be expelled by the vibration and the varnish V can be removed. It is possible to make it enter even a narrow gap such as between the wires 14 of the winding wire 13, and it is even more excellent in the effect of preventing the generation of voids.

Further, the varnish V is supplied from the three dropping ports 21a to the coil end portion 13a of the winding 13 and the stator core 12.
Therefore, the varnish V can be effectively impregnated over the entire stator 11 because the droplets are dripped toward the inner peripheral portion of the. Furthermore, the outer peripheral surface of the stator core 12 is a bag 22.
While still covered with, heat the stator 11 and varnish V
Since the hardening of the varnish V is performed early, the outflow of the varnish V can be prevented more effectively.

In the above embodiment, the varnish V is dropped while applying a slight vibration to the stator 11.
Further, the varnish V was dropped onto several portions of the stator 11, and the stator 11 was heated while the stator core 12 was covered with the bag 22, but these treatments were not always performed. Even if the varnish is drip-impregnated in a state where the adhesive member having flexibility is brought into close contact with the outer peripheral surface of the iron core, it is possible to sufficiently prevent formation of voids in the insulating layer. The purpose of the period can be achieved.

In addition, hot air may be supplied to heat the winding body, and various kinds of contact members can be used, and the structure of the device for impregnating the varnish can be further changed. The present invention can be variously modified and implemented without departing from the scope of the invention.

[0032]

As is apparent from the above description, according to the method for impregnating varnish for electric equipment of the present invention, the winding body is attached to the outer peripheral surface of the iron core while the adhesive member having flexibility is brought into close contact. Since the varnish is dropped and impregnated while rotating around its axis, the varnish is prevented from flowing out when the insulating layer is formed by the varnish, and the formation of voids is prevented as much as possible. It has an excellent practical effect of being able to do so.

In this case, if the winding body is dipped and impregnated with the varnish while applying minute vibrations simultaneously with the rotation, bubbles can be expelled and the varnish can be distributed between the wires of the winding. It is possible to fill even narrow gaps, and it is more excellent due to the effect of preventing the formation of voids.

If the varnish is dropped toward the coil end portion of the winding and the inner peripheral portion of the iron core, the varnish can be effectively impregnated over the entire winding body. Furthermore, by dripping and impregnating the varnish and then heating the winding body while keeping the contact member in close contact, the varnish can be prevented from flowing out during heating.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, and is a vertical cross-sectional front view of essential parts showing a state during a varnish impregnation process.

FIG. 2 is a side view showing a state during a varnish impregnation process.

FIG. 3 is a cross-sectional plan view showing a main part of a stator on which an insulating layer is formed.

FIG. 4 is a perspective view of a stator.

FIG. 5 is an enlarged perspective view of a coil end portion.

FIG. 6 is a cross-sectional plan view showing a main part of a stator before impregnation with varnish.

FIG. 7 is an enlarged vertical sectional view of a main part of a stator showing a conventional example.

FIG. 8 is a view corresponding to FIG.

FIG. 9 is a vertical sectional front view schematically showing a state during varnish impregnation processing.

[Explanation of symbols]

In the drawing, 11 is a stator (winding body), 12 is a stator core,
12a is a slot, 13 is a winding wire, 13a is a coil end portion, 14 is a wire, 15 is insulating paper, 19 is an insulating layer, 20 is a chuck device, 21 is a varnish supply nozzle, 21a is a drip port, 22 is a bag (adhesive). Member), 23 is a vibrator, and V is a varnish.

Claims (4)

[Claims] 1. A method of impregnating a winding body obtained by winding a winding around an iron core with a varnish, wherein the winding is performed in a state where a flexible contact member is brought into close contact with the outer peripheral surface of the iron core. A method for impregnating a varnish of an electric device, characterized in that the wire body is dropped and impregnated while rotating the wire body around its axis. 2. The method for impregnating a varnish of an electric device according to claim 1, wherein the winding body is drip-impregnated while applying minute vibration simultaneously with rotation. 3. The method for impregnating a varnish of an electric device according to claim 1, wherein the varnish is dropped toward the coil end portion of the winding and the inner peripheral portion of the iron core. 4. The electric wire according to claim 1, wherein after the varnish is dropped and impregnated, the winding body is heated with the contact member kept in contact. Equipment varnish impregnation method.