JPH0799758A - Varnish impregnation method of core - Google Patents

Abstract

PURPOSE:To prevent unneeded varnish from adhering at the same time eliminate the need for removing varnish by fitting a tube whose both edges are sealed and which has an improved heat resistance into the bolt through hole of a fixed core and then performing varnish drooping treatment. CONSTITUTION:When performing the varnish treatment of the stator of a rotary electric machine, a tube 27 which has improved heat resistance and whose both edges are sealed is fitted into a bolt through hole 24 since a stud through hole (bolt through hole) 24 for fixing a bearing bracket and a frame is formed at a stator core 22. Then, varnish treatment prevents varnish 26 from adhering the inside of the bolt through hole 24. Also. both edges of the tube 27 can be cut for passing a stud bolt as it is, thus eliminating the need for removing varnish inside and around the bolt through hole 24 and hence eliminating the operation for removing unneeded varnish before rotary machine assembly operation and hence drastically reducing the time required for rotary electric machine assembly operation.

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 a varnish of an iron core, which is an improved method of varnishing a stator of a rotating electric machine.

[0002]

2. Description of the Related Art In a stator of an electric device such as a rotary electric machine, a stator core having windings is varnished,
Insulation and heat resistance are being improved.
As a varnish impregnation treatment method of this type, conventionally, there is a dipping method in which a stator is dipped in a varnish made of a thermosetting resin and then the stator is housed in a heating furnace to heat and cure the varnish.
Further, while maintaining the inner diameter portion of the stator core, the stator core is rotated to drip and impregnate a varnish having good heat dissipation properties, and then the varnish impregnated in the stator is heated and hardened in a heating furnace. Etc. were used.

[0003]

However, as is apparent from FIGS. 8 and 9, the conventional drip impregnation treatment method is not applicable to the winding 3
The stator core 2 subjected to the above is held by the chuck 8, the varnish 6 is dropped from the nozzle 5 while rotating the stator core 2, and then the varnish 6 impregnated in a heating furnace (not shown) is cured by heating. is there.

In this prior art, there is a stud bolt through hole (hereinafter simply referred to as a bolt through hole) 4 in the stator core 2 for fixing a bearing bracket and a frame (not shown), and the bolt is used in the varnish processing step. The varnish 6 penetrates into the through hole 4 and heat-cured after the varnish treatment,
The varnish 6 that has entered the bolt through hole 3 is hardened. As a result, in order to fix the bearing bracket and the frame (not shown) in the assembly process of the rotating electric machine, the stud bolts (hereinafter, simply referred to as bolts) are fixed to the bolt through holes 4 described above. There is a problem that the varnish 6 attached to the inside is hardened and clogged, the bolt cannot pass, and the varnish 7 removal method must be performed before assembly, and this removal takes time.

Therefore, the present invention has been made in view of the above circumstances, and an object thereof is to prevent unnecessary varnish from adhering to the stud bolt through hole in the coil varnish processing step of the iron core and to remove the varnish. It is an object of the present invention to provide a method for impregnating a varnish of an iron core that can be eliminated.

[0006]

[Means for Solving the Problems] In order to solve the above problems, a tube having both ends having excellent heat resistance is attached to a bolt through hole of a stator iron core, and a varnish is applied to the bolt through hole after varnishing. It is possible to prevent adhesion and cut the both ends of the tube and pass the bolt as it is.

In addition, a round bar having a diameter larger than that of the bolts normally used is previously put in the bolt through hole of the stator iron core, and after the varnish treatment, the round bar is wiped off in a heating gel state to prevent the varnish from adhering to the through hole. You can do it.

Before the varnish treatment, a long hollow tube which is heat resistant and does not cause thermal deformation is mounted in advance in the bolt through hole of the stator core, and the varnish treatment is performed inside the bolt through hole. In addition to preventing the varnish from adhering to the hollow tube, the hollow tube that has been installed beforehand is inserted into the hollow tube without cutting the both ends, and the bolt is inserted into the hollow tube when assembling the rotary electric machine.

Further, after attaching an adhesive heat-resistant seal to both end faces of the bolt through hole of the stator core, varnish treatment is performed to prevent unnecessary varnish from entering the inside of the bolt through hole. Since the adhesive heat-resistant seal can be easily pierced with a bolt, the work of assembling the rotating electric machine can be performed without any trouble and the work of removing varnish is unnecessary.

[0010]

[Operation] Inserting a sealed tube, hollow tube, bolt, etc. inside the bolt through hole, or sticking the bolt through hole with an adhesive heat resistant seal to seal the bolt through hole against the varnish, so the bolt through hole of the stator core It is possible to prevent unnecessary varnish from adhering to the inside of the hole, and it is not necessary to remove the varnish, so that the time required for assembling the rotary electric machine can be greatly reduced.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a varnish processing method for a stator of a rotary electric machine will be described below with reference to FIGS. First, the configuration of the stator 11 of the rotary electric machine will be described with reference to FIGS. 5 to 7. The stator 11 is formed by laminating a plurality of thin steel plates having a plurality of open slots 12a formed in a ring shape on the inner peripheral side thereof.
A winding 13 is wound around the wire 2. A U-shaped insulator 14 is provided in the slot 12a.

On the other hand, the winding 13 is formed by winding a wire 15 such as a polyesterimide wire, and is wound around the stator core 12 in a state of being fixed by a wedge 16. The coil end portion 13 a housed in the slot 12 a and protruding from the end surface of the stator core 12 is fixed by a binding thread 17. Further, the coil 1 is wound at the coil end portion 13a.
The required connection between the three is made and the lead line is derived.

The stator 11 thus constructed is treated with a varnish to improve the heat resistance strength and the vibration resistance strength of the winding wire 13, strengthen the fixing force to the stator core 12, and improve the insulation effect. It is like this.

1 to 4 show an embodiment of a varnish processing method according to the present invention, which will be described with reference to it. First, as shown in FIG. 1, a stud bolt through hole (hereinafter simply referred to as a bolt through hole) 24 is formed in the stator core 22 for fixing a bearing bracket and a frame (not shown). A tube 27 having both ends sealed, which is excellent in heat resistance, is attached to the bolt through hole 24. By performing the varnish treatment, it is possible to prevent the varnish 26 from adhering to the inside of the bolt through hole 24. Also, tube 2
No. 7 does not need to remove the varnish inside and around the bolt through hole 24 because the both ends can be cut and a stud bolt (not shown) can be passed through as it is.

Next, as shown in FIG. 2, the bolt through hole 34
To prevent the varnish from sticking to the inside of the bolt through hole 34, insert a round bar 37 thicker than the diameter of the stud bolt that is normally used in advance and pull out the round bar 37 in the heated gel state after varnish treatment. This eliminates the need for varnish removal.

Next, as shown in FIG. 3, the bolt through hole 44
A long tubular hollow tube 47 (both ends are not sealed) which is heat resistant and does not cause thermal deformation is inserted into the tube, and is projected from the end of the stator core 42 to at least both coil end lengths. Then, varnishing is performed while inclining the stator core 42, and both ends of the hollow tube 47 are used as they are without being cut near the end faces of the stator core 42. Then, since the hollow tube 47 is a long object and is varnished while inclining the stator core 42, the through hole 4 is passed through the hollow tube 47 and the hollow tube 47.
4 Adhesion of varnish to the inside can be prevented, and removal of varnish is unnecessary. Further, since the hollow tube 47 is assembled as it is in a long state as a rotary electric machine and the stud bolt is inserted into the hollow tube 47, cutting of the hollow tube 47 is not necessary, and the productivity of assembly time is improved.

Next, as shown in FIG. 4, a bolt through hole 54
After sticking the heat-resistant adhesive seals 57 on both end surfaces of the varnish, varnish treatment is performed to prevent unnecessary varnish from entering the inside of the bolt through hole 54. Since the adhesive heat-resistant seal 57 can be easily pierced by a stud bolt (not shown),
It is possible to eliminate the need for varnish removal.

[0018]

As is apparent from the above description, according to the varnish processing method for the iron core of the present invention, unnecessary varnish invasion and varnish adhesion can be prevented inside the stud bolt through holes formed in the stator. To do. Further, the unnecessary varnish removal work before the rotating electric machine assembling process is unnecessary, and the excellent practical effect that the time of the rotating electric machine assembling work can be greatly shortened is achieved.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view in which a tube having both ends sealed is attached to a bolt through hole of an iron core showing an embodiment of the present invention,

FIG. 2 is a cross-sectional view of a stator in which a round bar is attached to a bolt through hole according to another embodiment of the present invention,

FIG. 3 is a cross-sectional view of a stator in which a long hollow tube is passed through a bolt through hole showing another embodiment of the present invention,

FIG. 4 is a cross-sectional view of a stator in which heat-resistant seals are attached to both end surfaces of bolt through holes according to another embodiment of the present invention,

FIG. 5 is a perspective view showing a structure of a stator,

FIG. 6 is an enlarged perspective view of a coil end portion of the stator showing the structure of the stator;

FIG. 7 is a partial cross-sectional view of the stator showing the structure of the stator;

FIG. 8 is a cross-sectional view of a stator showing a conventional example of varnish treatment,

FIG. 9 is a partial cross-sectional view of a stator showing a state in which unnecessary varnish is attached inside a bolt through hole showing a conventional example.

[Explanation of symbols]

2, 12, 22, 32, 42, 52 ... Stator core, 3,
13, 23, 33, 43, 53 ... Winding, 4, 24, 3
4, 44, 54 ... Stud bolt through holes, 6, 26, 3
6, 46, 56 ... Varnish, 27 ... Tube,
47 ... Hollow tube, 13a ... Coil end,
37 ... Round bar, 57 ... Adhesive heat-resistant seal.

Claims (4)

[Claims] 1. A method of impregnating a varnish having a stud bolt through hole in an iron core wound with a winding, wherein a tube whose both ends are sealed is attached to the stud bolt through hole of the iron core for varnish dropping treatment, and the stud bolt A method for impregnating a varnish of an iron core, which prevents varnish from adhering to a through hole. 2. A varnish is prevented from adhering to the inside of the stud bolt through hole by inserting a round bar into the stud bolt through hole of the iron core in advance and pulling out the round bar in a heated gel state after dropping the varnish. Method for impregnating varnish of iron core. 3. A varnish dropping process is performed by mounting a long hollow tube that does not cause thermal deformation in the stud bolt through hole of the iron core and projecting it from the end face of the iron core at least approximately equal to the coil end length while inclining the iron core. A method for impregnating a varnish into an iron core, characterized in that varnish is prevented from adhering to the through hole. 4. A varnish drip process is performed after sticking adhesive heat-resistant seals that can be pierced by stud bolts on both end faces of the stud bolt through hole of the iron core to prevent varnish impregnation inside the stud bolt through hole. Method for impregnating varnish of iron core.