JPS58171805A - Ac electromagnet - Google Patents

Abstract

PURPOSE:To reduce loss and noise and to increase attracting force by specifying the ratio of the area of the contact surface not enclosed by a shading coil to that of the contact surface enclosed by the shading coil. CONSTITUTION:An iron core 1 prepared by stacking up electric iron sheets stamped out in the form of E and tightened with rivets 3 is placed in the direction opposite to another iron core 2 prepared in the same manner as the iron core 1. Then grooves are made in the contact surfaces of the iron core 1 and shading coils 4 are provided therein. The contact surface is divided into two: the contact surface 5 not enclosed by the coil 4 and the contact surface 6 enclosed by the coil. The ratio of the area of the contact surface 5 to that of the contact surface 6 is set at 1:2.5-1:3.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an AC electromagnet used in electric contactors, auxiliary relays, and the like.

Generally, AC electromagnets used in am contactors and auxiliary relays are
A square coil is provided to reduce the pulsation of the magnet's attraction and to reduce noise. The first example of this electromagnetic soap is
11. At No. 111 Km, the iron core 1 was made by laminating electric iron plates punched into a figure 8 shape and tightened with rivets 3, and this iron core 1 has almost the same shape and configuration! A groove is provided on the surface of one iron core 1 that contacts the other iron core 2, and a so-called dark-circle coil 4 is provided, which forms a circuit by surrounding a part of this contact surface with a conductor. Therefore, the contact surface is the coil 4
The contact surface 5 is divided into a contact surface 5 which is not surrounded by a fill 4 and a contact surface 6 which is surrounded by a fill 4. Ignoring saturation of the iron core l and leakage of magnetic flux, the magnetic flux generated by the excitation coil (not shown) generates voltage in the shaded coil 4 and causes current to flow (the magnetic flux portion of the contact surface 5 that is not surrounded by the shaded coil 4). On the other hand, when the time ωt is plotted on the horizontal axis, the magnetic flux 6 on the contact surface 6 surrounded by the coil 4 is generated with a phase delay of α from the magnetic flux Φ1, as shown in FIG. 4 generates attractive forces F, , F, which are in phase with the magnetic flux Φ1. The magnitude of the attractive force F and the height of its pulsation are determined by the magnetic flux.

It is determined by the phase difference angle α, and the magnetic flux source phase difference angle α is:
Ratio between the area S of the contact surface not surrounded by the shaded coil 4 and the area S of the contact surface 6 surrounded by the coil 4 81 a 8
! , magnetic flux φ1. Φ! The difference in magnetic resistance of each magnetic path,
It is said that it is controlled by the resistance and reactance of the square coil 4. Here, as shown in No. 31111, the gap length between the contact surface 5 and the iron core 2 that is not surrounded by the coil 4 where the iron core 1 contacts the iron core 2! , and the contact surface 60 surrounded by the coil 4 is the iron core 2.
'4z g, K-v'jiJ1811 s- (where = constant) is obtained, and if K in this equation is made as large as possible, both magnetic fluxes φ1. It is said that the phase difference angle α of the mole is close to 90°, and the pulsation of the suction force F is small, which is effective in eliminating noise. However, the area is 8. cannot be made extremely small because the required attraction force F cannot be obtained unless the required magnetic flux φ1 is passed through, and it is difficult to polish the contact surface unless the gap lengths j,, j, are set to the same value. Yes, iron core l in the long run.

Considering the fact that there is deformation due to impact contact and wear, etc., the conditions necessary to increase Kt obtained from the above formula, I
I, l I, → large * 81+ 4 → There is a limit to making it small. Furthermore, in the past, it was difficult to measure the attraction force itself, and a method was used in which a weight was suspended from the object attracted by the heart electromagnet to find a value that could not be maintained by a heavy person. It is not possible to accurately determine the minimum suction force. Furthermore, since it is difficult to measure the resistance of the shaded coil, the relationship between the resistance of the shaded coil or the loss within this coil and the composite attraction force has not been determined.

Therefore, the ratio of the area S of the contact surface not surrounded by the conventional shade coil to the area S of the contact surface surrounded is 81 a
51 = 1: 2 is considered to be 2, but as can be seen from the above-mentioned current situation, this ratio is only empirical, and it is the one that has the highest suction power with the least loss and the lowest noise. It cannot be said that the area ratio is sufficient to provide an electromagnet.

The present invention was made in view of the above-mentioned points, and an object of the present invention is to provide an AC electromagnet with low loss, high attractive force, and low noise.

The purpose of this is to create an AC electromagnet in which iron cores formed by laminating a plurality of electric iron plates punched out in a figure 8 shape are placed facing each other, and a shaded coil is arranged on a part of the opposing contact surface of the outer legs of one of the iron cores. , the area ratio v of the contact surface not surrounded by the shade coil and the contact surface surrounded by the shade coil
This is achieved by setting x:zs to 1:3.

The basis of the present invention will be described in detail below based on experimental examples.

The present invention calculates the relationship between the composite attraction force and the loss in the shaded coil with respect to the area ratio between the contact areas not surrounded by the shaded coil of the iron core and the surrounded contact surface, and calculates the best area. First, a search coil is placed between the contact surface that is not surrounded by the shaded coil of the iron core and the contact that is surrounded, and the voltage induced in this search coil is calculated using an integrator. , the attraction force F11 F as determined by passing through a multiplier and an adder and shown in 2nd E,
The temporal changes in the composite suction force and pressure were determined from this graph. An accurate minimum suction force Fl can be determined from the shape of this composite suction force F. In addition, when the minimum suction force is large, the pulsation of the suction force is small, and based on this pulsation (
It is clear that the noise level is low.

In addition, the loss consumed in the bear-shaped coil was determined from the coil current determined by calculation and the (Is) resistance value determined from the material shape. The test cores had the same thickness, and the area ratio S1:82 was changed by changing the radius L (Fig. 3). The lengths were kept the same, and only the length along the core width was changed. Thus, the area ratio s as shown in FIG.
: 8. Then, the relationship between the minimum suction force Fl and the loss P was determined. In Figure 4, the materials of the bearer coil used in the experiment are steel and aluminum for ordinary bearer coils, and the minimum attraction force FJ of these materials is respectively Fe.
u and FAj, and losses were expressed as Pcu and PAj, respectively.

In general, the attraction force is at its maximum at a value of 81:82, and it is conceivable that it decreases if it deviates from this value, but the experimental results show that when steel is used as the pick-up coil, as shown in the same WjArr:: Even if aluminum material is used, the area ratio is 8H:82=1:3 and the lowest suction force is F! It was found that ``is'' the biggest factor. Also, it is natural that the loss increases as S becomes larger, but S, : s′,
It was found that as the area ratio increases from around zl:3, it suddenly decreases (6). . From the results shown in Figure 4, it is clear that the contact surface not surrounded by the shaded coil and the contact surface surrounded by the shaded coil are designed to have a width in the direction that reduces the loss in the shaded coil, taking into account the manufacturing error in area ratio. The area ratio with the surface is 81: B@-1:
It was determined that setting the ratio from 2.5 to l:3 was the best option.

In addition, this area ratio is calculated on the opposing contact surfaces of the outer legs of one of the E-shaped cores facing each other. It is also possible to provide the contact surface 5 on both sides of the part 60 surrounded by the bear-weir coil 4 on both sides of the iron core 1, approximately in the center of the width of the facing surfaces of both iron cores 1.2, and As shown in FIG.
The contact surface 5 which is not surrounded by the contact surface 5 and the contact surface 6 which is surrounded by vII may be provided separately.

As described above, according to the present invention, E
In an AC electromagnet having a shaded coil arranged on a part of the opposing contact surfaces of one of the outer legs of a letter-shaped core, the area ratio of the contact surface surrounded by the shaded coil and the contact surface not surrounded by the shaded coil is 1:2. By setting the ratio between .5 and 1:3, it is possible to provide an alternating current electromagnet with little loss, a large attraction force, and low noise.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an AC electromagnet core to which the present invention is applied;
Figure 2 is a waveform diagram showing temporal changes in the magnetic flux flowing through the core shown in Figure 1 and the attractive force generated by this magnetic flux. Figure 3 wA is an enlarged side view of the core shown in Figure 1 near the shaded coil. Figure 4 is a graph showing the relationship between the minimum attraction force and coil loss with respect to the area ratio of the contact surface not surrounded by the shaded coil and the contact surface surrounded by the coil. @ Figures 5 and 6 are side views showing the arrangement of a shaded coil to an iron core to which the present invention is applicable. 1.2... Iron cores facing each other, 4... Shaded coil, 5... Contact surface not surrounded by shaded coil,
6...Contact surface surrounded by shaded coils. Fig. 11 Fig. 3''jr Fig. 4 JP-A-58-171805 (4)

Claims (1)

[Claims] 1) In an AC electromagnet, in which iron cores formed by laminating a plurality of electrical iron plates punched into a single character shape are placed facing each other, and a darkening fill is arranged on the opposing contact surfaces of the outer legs of one of the cores, the darkening is removed. An alternating current electromagnet characterized in that the area ratio of the contact surface not surrounded by the coil to the contact surface surrounded by the bear-scattered coil is set from 1:u to 1=3.