JPS607374B2 - Manufacturing method for involute iron core - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for manufacturing an impolite core.

2. Description of the Related Art An implant core is known, in which a plurality of fixed-sized steel plates are individually curved into an impolute shape and layered in a spiral shape.

The use of such an iron core as an iron core constituting a reactor with a gap was invented by the present inventor,
It is proposed separately. That is, as shown in FIG. 1, a plurality of impolute cores 1 are stacked together via a gap spacer 2 to form a columnar core 3, and a coil 4 is wound around it. The plurality of upper and lower ends of the columnar iron core 3 are connected by a yoke 5 and integrated by a tightening stud 6. Note that 7 is a fixing band for the iron core 1. When such an iron core is used, various advantages can be obtained, such as reducing loss due to eddy current, preventing local heating, and improving the bookkeeping ratio. By the way, in order to manufacture this type of iron core, conventionally, a steel plate is bent into an impolute shape using a single cutting die designed in advance in an impolute shape, and then the steel plates are individually layered in a spiral shape. was. However, with this method, not only is it necessary to prepare an impolite-shaped cutting die, but also the steel plates must be bent individually using the cutting die, and the processed steel plates must be layered one after another. Therefore, its production was extremely troublesome. The purpose of this invention is to easily manufacture an impolute core.

In particular, an object of the present invention is to make it possible, when a steel plate is processed and formed into an impolute shape using a processing machine, to obtain a desired impolite core while maintaining the formed state.

Embodiments of the invention will be described below with reference to the drawings.

First, as shown in FIG. 2, a small ring 11 is prepared, and one end of a plurality of steel plates 12 cut into lengths in advance is fixed to the outer periphery of the ring by welding or the like. Therefore, each steel plate 12
are arranged and fixed radially around the outer circumference of the ring 11. Then, while rotating the ring 11 in one direction, an external force is applied from the outer end of the steel plate 12 toward the rotational axis of the ring 11 against the elastic force of the steel plate. Various means for applying this external force can be considered; for example, a band is wound around the outer periphery of the steel plate 12 and the band is tightened so that the radius of the band gradually decreases, or a roller rotatably attached to the tip as shown in Fig. 3 is used. The arm 14 supporting the steel plate 13 may be pushed from the outer end of the steel plate 12 toward the center. In any case, each steel plate 12 is bent while one end of the steel plate 12 is fixed and the ring 11 is rotated, so that each steel plate is gradually bent into an impolute shape while being in close contact with each other. , and its outer periphery is circular.

In this way, processing is completed until the diameter reaches the finished size. However, if the external force that had been applied until then is removed, the steel plate will return to its original state due to the restoring elastic force, so it is necessary to maintain the shape at the end of processing and forming even when the external force is removed. be. For this purpose, as shown in FIG. 3, a heat-resistant ring 15 previously manufactured to match the finished external shape is attached to the outer periphery of the processed and formed part 16, and then the external force is released. As a result, the dimensions of the processed molded product 16 at the time of completion of the processed molding are maintained. ring 1
5 may be replaced with a steel strip. The reason why the ring or steel strip is made heat resistant is to prevent the ring (or steel strip) from being elongated by the cleave during annealing in the next process, and the finished dimensions will change significantly and become no longer the required values. This is to prevent this. Another advantage is that the ring can be used repeatedly. As above,
The processed molded product 16, which has been processed and formed into an impolute shape against the restoring elastic force of the steel plate, is annealed in order to remove the distortion of the steel plate and to eliminate the restoring elastic force.

This annealing completes the production of the impolite core 17. However, in order to correct the tightening force loosened due to annealing, the outer periphery is tightened using, for example, a bandeau 8, as shown in FIG. 6, and the finished size is reduced to the required value. This tightening is performed using the band metal fittings 19. Then, in order to maintain this vertically attached state, they are bound with insulating tape or bands. The reason for the insulating property is to prevent short-circuit current from occurring in the tape (or band) by interlinking with the magnetic flux passing through the iron core. The tape (or band) is preferably made of glass, or it may be semi-cured and impregnated with a thermosetting resin. When using this, the iron core 17 after being hammered still has a high temperature due to residual heat,
When the temperature is the temperature required for curing the semi-curable tape, it is convenient that if the semi-curable tape is used to bind the tape, it will simultaneously cure and increase the binding strength. Of course, after bundling, it may be heated and hardened separately to increase the cohesive strength.
As detailed above, according to the present invention, by applying an external force, the entire steel plate is simultaneously bent into an integral shape, and the processed and formed state is maintained even when this process and forming is completed and during annealing. It can be processed with
Since it is bound with an insulating band or tape, it is possible to produce an impolite core that does not loosen during tightening, and the overall manufacturing process is simpler compared to conventional layering means using cutting dies.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an example of the use of an impolute core, Fig. 2 is a plan view showing the processing and forming state, Fig. 3 is a plan view when the processing state is held with a ring, and Fig. 4 is Fig. 3. FIG. 5 is a plan view showing the tightened state after the anchor is scorched, and FIG. 6 is a plan view showing the finishing process. 11...Ring, 12...Steel plate, 15...Ring, 18...Band. Younger brother' diagram Younger brother Z diagram Figure 3 Jubutsu diagram Figure 5 Younger brother diagram 5

Claims (1)

[Claims] 1. A plurality of steel plates are fixed to the outer peripheral surface of a ring so that the steel plates are arranged radially in parallel around the ring,
While rotating the ring in one direction, applying an external force from the outer end of the steel plate in a direction toward the rotational axis of the ring, the steel plate is bent into an involute shape, and upon completion of the forming, An involute iron core formed by attaching a heat-resistant ring or band to the outer periphery of the steel plate to maintain the processed and formed state, then annealing it, tightening it from the outer periphery with the ring or band, and then binding it with an insulating tape or band. Production method. 2. The method for manufacturing an involute core according to claim 1, wherein the insulating tape or band is a semi-hardening tape and is hardened by heating after binding. 3. The method of manufacturing an involute iron core according to claim 1, wherein the insulating tape or band is a semi-hardening tape and is hardened by residual heat during annealing after binding.