JPS6222338B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the structure of an electric motor in which a stator is formed by winding a coil around an annular iron core.

The stator of an electric motor is generally formed using an iron core with slots, and since the windings are housed in the slots, the windings do not protrude from the inner and outer circumferential surfaces, and the outer circumference is made of a durable material. It can be press-fitted into a steel plate frame, etc., and the rotor can be disposed on the inner periphery with a small gap, making it possible to construct an efficient and durable electric motor.

However, in electric motors in which the stator is formed by winding coils around an annular core (in a toroidal shape), the coils are uniformly exposed on the inner and outer surfaces of the core. It becomes very difficult to fix the stator.

Of course, if a part of the annular core is provided with an extension for support, this can be supported, but if the extension is made sturdy to securely fix it, it will take up a large area. However, there are problems in that it becomes a hindrance to winding the coil, and that the coil cannot be wound around the extended portion, which is unfavorable in terms of characteristics, and furthermore, the structure of the frame becomes complicated.

The present invention has been made in view of the above circumstances, and an object of the present invention is to eliminate the above-mentioned drawbacks and provide a highly productive electric motor.

The present invention will be explained below based on an embodiment shown in the drawings.

FIG. 1 is a longitudinal sectional view of an electric motor according to the present invention, FIG. 2 is a front view of the electric motor, and FIG. 3 is a diagram showing the shape of a bracket. 4 and 5 are diagrams showing the shape of the stator, and FIG. 6 is a diagram showing the state in which the stator is placed within the mold.

In the figure, reference numeral 1 denotes a stator of an electric motor, in which an annular iron core 2 without slots is inserted into a hollow spool 3, and a coil 4 is wound around the spool 3 (in a toroidal shape).

The iron core 2 is formed into two parts, and the spool 3 is made of thermosetting phenol resin or the like, and is formed into three parts so that the iron core 2 can be easily inserted.

The spool 3 and the iron core 2 are each bent at the same bending rate, and the spool 3 is formed into a tubular shape,
It is configured such that the iron core 2 is inserted therein.

Further, the inner circumferential wall of the spool 3 is formed thin in order to facilitate effective magnetic flux, and the side walls 5 formed at both ends of the spool 3 have fitting grooves 6a formed in the end bracket 6. Part 5a
is formed.

As shown in FIG. 3, the groove 6a of the end bracket 6 has a portion where the groove 6a is formed extends three times in the circumferential direction.
The fitting portions 5a of the spool 3 are formed to fit into the grooves 6a formed in these three directions.

Therefore, by fitting the fitting portions 5a into the grooves 6a, the axial center of the spool 3 and the axial center of the end bracket 6 are inevitably aligned.

Furthermore, radial positioning can be easily performed by forming an end in the radial direction and abutting the fitting portion 5a of the spool 3 against this end without opening the groove 6a in the radial direction.

The stator 1 is inserted into the groove 6 of the end bracket 6.
The frame of the electric motor is constructed by fitting the fitting portion 5a into the molding layer 7a and covering it with a mold layer 7 made of synthetic resin or a synthetic resin and an inorganic material such as sand.

Further, the end bracket 6 has a cylindrical center, and a rotation shaft 9 of the rotor 8 is formed in this cylindrical portion 6b.
Bearings 10 and 11 are attached to support the shaft. 12 is a rear lid.

That is, the end bracket 6 and the upper mold 13 can be fixed in the radial direction by using the unevenness formed in the axial direction, and in the axial direction by using the unevenness in the radial direction.

Therefore, the end bracket 6 is fixed in the radial direction by its unevenness, and is held between the upper mold 13 and the lower mold 14 via the spool 5 in the axial direction.

Since the groove 6a of the end bracket 6 and the fitting portion 5a of the spool 3 are fitted, the stator 1 and the end bracket 6 are held in a predetermined position.

Further, 13 is an upper die of the mold injection mold and is formed in a shape that fits the end bracket 6, 14 is a lower die, and 15 is a gate for resin injection.

To assemble this electric motor, first, coils 4 are wound around each spool 3 (in a toroidal shape), the windings are performed, the iron core 2 is inserted, and the respective divided parts of the iron core 2 are joined. to form the stator 1.
Then, the fitting portion 5a of the spool 3 is fitted into the groove 6a of the end bracket 6, and the stator 1 is attached and fixed to the end bracket 6.

Next, the end bracket 6 to which the stator 1 is attached is inserted into the upper mold 13, and then the lower mold 14 is set. Therefore, the stator 1 is positioned and fixed in the horizontal direction by the fit between the end bracket 6 and the upper mold 13, and is securely fixed in the axial direction by being held between the upper and lower molds 13 and 14 via the spool 5. Ru. At this time, the cylindrical portion 6b of the end bracket 6 is formed deeply, and this cylindrical portion 6b is attached to both the upper and lower molds 13, 1.
It can also be clamped with 4.

After that, resin is injected from gate 15 at a pressure of about 20 to 40 kg/cm ² . Since the stator 1 is supported as described above even when pressure is applied by this injection, its movement is prevented.

After molding, it is taken out from the upper mold 13 and lower mold 14, and the rotor 8, rotating shaft 9, bearings 10, 11, rear cover 12, etc. are attached to assemble the electric motor.

According to the configuration described above, it is possible to reliably prevent the stator from moving within the injection mold due to the injection pressure of the resin, so that the stator is not unevenly distributed in the mold.

In addition, since the stator 1 and the end bracket 6 are easily fixed with the same axes due to the fitting between the groove 6a and the fitting part 5a, the end bracket 6 and the stator can be easily fixed with the same axis between the end bracket 6 and the upper and lower molds. The stator 1 can be easily positioned, and the stator 1 can be more firmly fixed by using an adhesive in conjunction with the stator 1, so the stator 1 will not move even if the injection pressure is considerably increased.

In addition, when pouring resin molten metal, the stator is formed into an annular shape, the coils are tightly attached along the outer surface, and it does not have a coil end like a stator using a conventional slotted iron core, so even if high pressure There is very little risk of damage to the coil even when resin hot water is injected, and even if the resin hot water has a high viscosity, it can be injected in the same way, and the molding conditions are extremely excellent.

On the other hand, the gist of the present invention is a structure in which a stator formed in an annular shape is fixed to a bracket, and the bracket and stator are integrally molded with resin, etc., and the shape of the bracket is not limited to this embodiment. do not have.

Therefore, the shape of the bracket should be changed as appropriate according to the specifications, by changing the processing method such as pressing or casting when using a metal such as a steel plate, or by changing the mold for the bracket when using a resin bracket. Can be used.

Furthermore, instead of providing fitting parts for the stator and bracket, respectively, as in this embodiment, they may be simply fixed with an adhesive.

According to the present invention, since the frame is formed by integrally molding the bracket and the stator, fewer steps are required and productivity is extremely high.

Furthermore, the frame is constructed by integrally molding a bracket made of metal such as a steel plate or hard resin, so the structure is robust. It is also possible to expose a portion of this bracket to the outside from the mold layer and form a flange at this exposed portion.

In particular, when the bracket is made of a hard resin, eddy currents associated with the movement of the magnetic field will not occur in the brackets, and the possibility that slight reverse torque will occur due to eddy currents is also eliminated.

Furthermore, positioning of the stator during molding is extremely easy, and sufficient external insulation of the windings can be obtained because the stator is covered with synthetic resin or the like.

As explained above, the present invention forms a stator by winding a coil around an annular iron core, and molds the stator with resin without unevenly distributing it.Moreover, it is easy to attach to a mold, and has high productivity. This provides an excellent electric motor.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of an electric motor according to the present invention, FIG. 2 is a front view of the electric motor, and FIG. 3 is a diagram showing the shape of a bracket. Further, FIGS. 4 and 5 are diagrams showing the shape of the stator, and FIG. 6 is a diagram showing the state in which the stator is placed in the mold. 1...Stator, 2...Iron core, 4...Coil, 5
a... Fitting portion, 6... Bracket, 6a... Groove.

Claims (1)

[Claims] 1 Wind the wire in a trodal shape on the hollow spool,
A divided annular iron core is attached to the hollow part of this spool, and the divided parts of the iron core and the spool are respectively joined to form a stator, and a bracket having a part that fits with the spool is formed and integrated. An electric motor characterized in that it is held in a mold and integrally molded with a synthetic resin or a mixture of a synthetic resin and an inorganic material.