JPS6336502A - Electromagnetic actuator - Google Patents

Abstract

PURPOSE:To enable the magnetic flux passing through the moving core and the stationary attractor to be changed and adjusted as a result by changing the insertion amount of the adjusting core into the stationary attractor, thereby simultaneously changing the magnetic resistances of the first adjusting magnetic circuit and the second adjusting magnetic circuit. CONSTITUTION:The magnetic resistances of two adjusting magnetic circuits, a first adjusting magnetic circuit 13 and a second adjusting magnetic circuit 9, are simultaneously adjusted by changing the insertion amount of an adjusting core 8 into a stationary attractor 2, whereby the magnetic flux passing through a moving core 3 and the stationary attractor 2 is adjusted as a result. Moreover, the relation between the insertion amount and the magnetic flux becomes linear, or in other words, the relation between the insertion amount and the operating voltage becomes linear, so the operating voltage adjustment becomes easy. In this manner, an electromagnetic actuator can be obtained which is easy to adjust whether the operating voltage is high or low.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electromagnetic actuator that has a permanent magnet in its magnetic circuit and is driven by instantaneous energization from an external power source when it is to be activated.

Conventional technology The heat generation of the electromagnetic coil can be avoided from the past.1. In order to save power on the drive circuit side, an electromagnetic actuator is used in which a permanent magnet is used, the electromagnetic coil is used only for instantaneous excitation, and the state is maintained by the permanent magnet. In particular, in recent years, the use of dry batteries, etc. in addition to AC power sources has been increasing as a drive power source, and as a result, the voltage conditions applied to the stain magnetic actuator are limited due to the temperature characteristics and load resistance characteristics of the battery that serves as the power source. comes out. Therefore, it becomes necessary to keep the voltage at which the self-holding solenoid operates within a certain range corresponding to the power supply.

In response to these problems, efforts have been made to improve the accuracy of the magnetic properties of the materials used in the components of electromagnetic actuators and the dimensional accuracy of the parts, thereby suppressing variations in the voltage required for actuation. Since it is difficult to keep the operating voltage within a certain range, various methods of adjusting the operating voltage have been adopted.

An example of the conventional electromagnetic actuator mentioned above will be described below with reference to the drawings.

FIG. 6 schematically shows the structure of a conventional example.

In FIG. 5, the permanent magnet 1 is magnetized in the thickness direction and has a through hole 1& in that direction.

A fixed attracting body 2 made of a magnetic material is provided on top of the movable iron core 3 made of a magnetic material so that a movable iron core 3 made of a magnetic material can be attracted to and removed from the attracting surface 4. The first fixed yoke 5a and the second yoke are made of magnetic material.
Fixed yoke 6b, permanent magnet 1, fixed adsorption body 2, movable iron core 3
A magnetic circuit 6 of the permanent magnet 1 is formed, and the movable iron core 3 is attracted and held on the fixed attraction body 2 by the attraction surface 4.

The driving electromagnetic coil 7 guides the movable iron core 3 vertically sliding in its center, and also excites the magnetic circuit 6. A female threaded portion is provided at a position corresponding to the through hole 1a of the permanent magnet 1 of the second fixed yoke 5b, and an adjusting iron core 8 made of a mother material and having a male threaded portion at that portion is attached to the through hole 1 & It is screwed through the
The structure is such that the gap E with respect to the fixed adsorbent 2 can be varied. An adjustment magnetic circuit 9 that does not include the movable iron core 3 is formed between the permanent magnet 1, the second fixed yoke sb, the adjustment iron core 8, and the fixed adsorption body 2. A spring receiver 1 is attached to the tip of the movable iron core 3.
0 is attached, and a compression spring 11 is provided between the first fixed yoke 5 and the first fixed yoke.

The operation of the electromagnetic actuator configured as described above will be described below.

The basic operating principle is that a voltage is momentarily applied to the stain magnetic coil 7 by an external drive power source so that a magnetic field is generated in the opposite direction to the magnetic field direction of the magnetic circuit 6. , the suction holding force between the movable iron core 3 and the fixed suction body 2 on the suction surface 4 weakens, and the compression spring 1 exceeds this suction holding force.
Due to the repulsive force of 1, the movable iron core 3 is moved away from the suction surface 4 and pushed up. Conversely, although not shown in the figure, when the movable iron core 3 is pushed up, the electromagnetic coil 7
By applying a voltage to generate a magnetic field in the same direction as that of the permanent magnet 1, it is possible to overcome the repulsive force of the compression spring 11 and return the movable iron core 3 to the attracting and holding position.

Here, the movable iron core 3 is pushed up, with the suction holding force in the suction holding state between the movable iron core 3 and the fixed suction body 2 described above being F, and the repulsive force of the compression spring 11 being f.

In other words, if the voltage applied to the electromagnetic coil 7 required for operation is the operating voltage V, the value of the operating voltage V is determined depending on the difference (F - f) value between F and f, as can be understood from the operating principle. be done. That is, when the attracting and holding force F is large or the repulsive force f is small, the operating voltage V becomes large, and conversely, when F is small or f is large, V becomes small. In addition, the movable iron core 3 is attached to the suction surface 4.
In a state where it is further away, the larger the repulsive force f of the compression spring 11 is, the larger the operating voltage V for re-adsorption becomes. Therefore, the strength of the compression spring 11 has opposite effects on the operating voltage V when it separates and when it attracts.

Here, the magnetic flux Φ1 due to the permanent magnet 1 passing through the magnetic circuit 6 is generated by the movable iron core 3, the first fixed yoke 6a, which constitutes the magnetic circuit 6,
It is greatly influenced by variations in the magnetic permeability, that is, magnetic properties, of the second fixed yoke 5b, the fixed attracting body 2, etc., the surface roughness of the attracting surface 40, and the magnetic properties of the permanent magnet 1 itself.

On the other hand, the attraction and holding force F is determined in such a manner that it is proportional to the magnetic flux Φ1.

This shows that even if electromagnetic actuators are assembled and manufactured with the same structure, the attraction and holding force F of each individual object varies greatly due to variations in the magnetic properties of the magnetic materials of the component parts. Even if the repulsive force f of 11 is constant, the differential force (F-f) will vary, and as a result, the operating voltage V will vary for each individual object.

Therefore, as mentioned above, if there is a limit to the voltage of the external drive power supply and it is necessary to keep the operating voltage V within a certain range, the solution is to keep (F-f) within a certain range. Either adjust the repulsive force f of the compression spring 11 or
A method is adopted in which the attraction and holding force F is adjusted by changing the magnetic flux Φ1.

This conventional example shows the latter method of adjusting the attraction and holding force F, and its operation is as follows.

According to the above-mentioned structure, the gap l between the fixed adsorption body 2 and the adjusting iron core 8 can be changed by rotating the threaded part of the adjusting iron core 8, and since the gap E becomes a magnetic gap, the adjusting magnetic circuit 9
This means that the magnetic resistance can be varied. In other words, when the gap g is made smaller, the magnetic resistance of the adjusting magnetic circuit 9 becomes smaller, and the total magnetic flux Φ caused by the permanent magnet 1 flows in a distributed manner between the magnetic circuit 6 and the adjusting circuit 9 (leakage flux to other than both magnetic circuits is reduced). For ease of understanding, the magnetic flux Φ2 flowing through the adjusting magnetic circuit 9 increases, and conversely, the magnetic flux Φ1 flowing through the magnetic circuit 6 decreases, and the attracting and holding force F decreases.

On the other hand, if the gap 1 is increased, the magnetic resistance of the adjusting magnetic circuit 6 increases, so Φ2 becomes smaller, and conversely, Φ1 becomes sharper, so the attraction and holding force F increases.

In this way, by being able to vary the gap l between the adjusting iron core 8 and the fixed adsorption body 2, the magnetic resistance of the adjusting magnetic circuit 9 is changed and its magnetic flux Φ2 is changed, and finally the magnetic flux Φ of the magnetic circuit 6 is changed.
, will change. In other words, this does not mean changing the adsorption/holding force F of the movable iron core 3 to the fixed adsorption body 2, but the operating voltage is adjusted so that the difference (F-f) between the movable iron core 3 and the repulsive force f of the compression spring 11 is kept within a certain range. This means that the variation in V can be kept within a certain range.

Problems to be Solved by the Invention However, the above configuration has the following problems.

FIG. 6 shows the gap between the adjusting iron core 8 and the fixed adsorbent 2, 71!
The figure shows the situation when the is varied. In FIG. 6(A), l=o, and in FIG. 6(B), 1=14. Figure 6(C) shows β=
This is the case of A6. E6 shows a state in which the tip of the adjusting iron core 3 is at approximately the same position as the lower end surface of the permanent magnet 1 of the second fixed yoke 5b.

The relationship between the increase in β and the operating voltage V is shown in FIG.

In FIG. 7, the vertical axis shows the operating voltage V, and the horizontal axis shows the gap E, and as the gap E increases, the operating voltage V becomes higher. However, the correlation is not linear and E=0
In the vicinity, a slight change in e causes a large change in V, but 1=
In the vicinity of 14 to 16, the change in V is very small. This is l = .

In the vicinity, the magnetic resistance of the adjustment magnetic circuit 9 changes greatly with a change in E, but as l becomes large, the magnetic resistance is already quite large compared to the dimensional change, and almost no change in magnetic flux Φ2 occurs. .

As can be seen from these, when the necessary adjustment of the operating voltage V is as low as V2 shown in FIG. Assuming that the reverse VCV is the same width as V, ~v2, if it is as high as v3 to v4, then Kana 2
There is an allowance for This means that when the adjustment operating voltage V is low, even a slight change in the gap β dimension will cause a sharp change in the operating voltage V, so it is necessary to increase the dimensional accuracy and it is extremely difficult to make adjustments. become. Moreover, as in this conventional example, the male screw of the adjusting iron core 8 and the second fixed yoke 5b
The operating voltage V will change even if there is some looseness with the female screw, so it must be adjusted to avoid any looseness.

On the other hand, when the adjustment operating voltage V is high, the tolerance of the gap β will be significantly different than when V is low even with the same adjustment voltage width. Even if the operating voltage V is adjusted within the same range, the allowable width of the gap β differs depending on whether it is high or low, which makes the adjustment work somewhat difficult.

As described above, the conventional adjustment method has a problem in that the adjustment work is extremely difficult because there are cases where very high precision is required and cases where there is a relatively large tolerance.

Moreover, since the adjusting iron core 8 is fixed by protruding from the second fixed yoke 5b, the gap β changes due to stress applied from the outside, and the characteristics of the operating voltage V change. had.

The present invention solves the above-mentioned problems by providing an electromagnetic actuator that makes the relationship between the operating voltage V and the gap E close to linear, and allows easy adjustment whether the operating voltage V is low or high.

Means for Solving the Problems In order to solve the above problems, the present invention provides a magnetic circuit formed between a permanent magnet, a fixed adsorption body into which an adjustment iron core is inserted, a movable iron core, and a fixed yoke, and an electromagnetic coil that excites a circuit, and a part of the magnetic circuit that passes entirely through the fixed attracting member is connected to a branch magnetic circuit that passes through the fixed attracting member itself, and one end passes from the fixed attracting member to the adjusting iron core and returns to the fixed attracting member. The fixed adsorption body which does not include the movable iron core, the adjustment iron core,
A second adjustment magnetic circuit is provided between the fixed yoke and the permanent magnet.

Effect The present invention uses the above-described configuration to simultaneously adjust the magnetic resistance of two adjusting magnetic circuits, the first adjusting magnetic circuit and the second adjusting magnetic circuit, by changing the insertion amount of the adjusting iron core into the fixed adsorption body. As a result, the magnetic flux passing through the movable iron core and the fixed adsorbent is adjusted.

Moreover, since the relationship between the insertion amount and the magnetic flux becomes linear, or in other words, the relationship between the insertion amount and the operating voltage becomes linear, it becomes easier to adjust the operating voltage.

EXAMPLE An example of the present invention will be described below with reference to the drawings.

FIG. 1 shows a sectional view of an electromagnetic actuator in an embodiment of the present invention.

In FIG. 1, a permanent magnet 1 is magnetized in the thickness direction and has a through hole 1a in that direction.

A fixed adsorption body 2 made of a magnetic material is provided thereon, and an insertion hole 2a having a female threaded portion is bored at a position corresponding to the through hole 1a on the side of the permanent magnet 1. The movable iron core 3 is capable of attracting and detaching from the attracting surface 4. Further, an adjustment iron core 8 having a male diagonal portion made of a magnetic material is inserted into the insertion hole 2B of the fixed adsorption body 2 so as to pass through the through hole 1a of the permanent magnet 1, and is screwed. At the same time, the amount of insertion can be varied.

The magnetic circuit 6 of the permanent magnet 1 is formed by the first fixed yoke 51L and the second fixed yoke 6b made of magnetic material, the permanent magnet 1, the fixed adsorption body 2 into which the adjustment iron core 8 is inserted, and the movable iron core 3. Movable iron core 3
is held by suction on a fixed suction body 2 with a suction surface 4. The driving electromagnetic coil 7 guides the movable iron core 3 to slide up and down through the center thereof, and also excites the magnetic circuit 6. A hole 12 having the same thickness as the through hole 1a is provided at a position corresponding to the through hole 1a of the permanent magnet 10 of the second fixed yoke 6b, so that the adjusting iron core 8 can be rotated from the outside. .

Here, the magnetic circuit 6 includes a branch magnetic circuit 12 that passes through the fixed adsorbent 2 itself, and a branch magnetic circuit 12 that passes through the fixed adsorbent 2 itself, and a branch magnetic circuit 12 that passes through the fixed adsorbent 2 at one end, passes through the adjustment iron core 8, and then passes through the fixed adsorbent 2 again. 1 adjustment magnetic circuit 13.

On the other hand, the permanent magnet 1, the second fixed yoke 6b, and the adjustable iron core 8
, a second adjustment magnetic circuit 9 that does not include the movable iron core 3 is formed between the fixed adsorption bodies 2. A spring receiver 10 is attached to the tip of the movable iron core 3, and a compression spring 11 is provided between it and the first fixed yoke 6a.

Now, in the above configuration, the operating principle is basically the same as that described in the conventional example, so the explanation will be omitted, but the difference from the conventional example is that the magnetic flux passing through the magnetic circuit 6 is different from the fixed adsorbent 2. When passing through, the magnetic flux Φ1a of the shunt magnetic circuit 12 passes through the fixed attracting body 2 itself, and the magnetic flux Φ, b of the first adjusting magnetic circuit 13 flows through the adjusting iron core 3 and then again through the fixed attracting body 2. Moreover, this magnetic flux Φ1b is the adjusting iron core 8
This is a point that can be changed depending on the amount of insertion.

This means that the magnetic flux Φ1 flowing through the magnetic circuit 6 is not only influenced by changes in the magnetic flux Φ2 of the second adjusting magnetic circuit 9, as in the conventional example, due to the variable insertion amount of the adjusting iron core 8. Furthermore, this means that Φ1 itself is directly affected by a change in magnetic flux Φ1b.

The operation will be explained below with reference to the drawings. FIG. 2 shows a diagram when the distance between the adjusting iron core 8 and the tip of the insertion hole 2N provided in the fixed adsorption body 2 of this embodiment, that is, the insertion amount is changed.

In FIG. 2, (A) shows the state where the insertion amount is L:L□#O, (mon) shows the state when L==L, and (C) shows the state when L=I, 2. The magnetic flux passing through the second adjusting arsenic circuit 9 is Φ2
, the magnetic flux passing through the magnetic circuit 6 is Φ4, the first adjustment magnetic circuit 13
The magnetic flux passing through is Φ1b, and the magnetic flux passing through the shunt magnetic circuit 12 is Φ
1a, Φ1=Φ, a+Φ2b.

On the other hand, if the total magnetic flux due to the permanent magnet 1 is Φ,
Φ=Φ1+Φ2. However, for the sake of clarity, leakage magnetic flux to areas other than these magnetic circuits will be ignored.

Now, if we look at how the magnetic flux changes in detail under each condition, in the state shown in Figure 2 (mu), that is, I, :Lo:0,
Adjustment iron core 8 and second fixed yoke 5b in second adjustment magnetic circuit 9
Since the magnetic gap between them is very large and the magnetic resistance is large, the magnetic flux Φ2 has a very small value. On the other hand, the magnetic flux Φ1b flowing through the first adjustment magnetic circuit 13 is
Since the distance between the innermost part of the insertion hole 2 & and the tip of the adjusting iron core 8 is zero, the magnetic gap is also equal to zero, the magnetic resistance is extremely small, and Φ1b is also at its maximum value. The magnetic flux Φ1a passing through the shunt magnetic circuit 12 is determined by the area obtained by subtracting the cross-sectional area of the insertion hole 2a from the cross-sectional area of the fixed attracting member 2.

Next, in the state shown in FIG. 2 (B), that is, L==L1, the adjusting iron core 8 and @2 fixed yoke 6b approach each other, and the magnetic gap between them becomes smaller than in the case of L20, and the second adjusting magnetic The magnetic resistance of the circuit 9 becomes smaller, allowing the magnetic flux to pass through more easily, and Φ2
increases. On the other hand, Φ1b is the insertion hole 2 of the fixed adsorption body 2.
Since the distance between the innermost part of & and the tip of the adjusting iron core 8 increases, the magnetic resistance of the first adjusting magnetic circuit 13 increases, and L ==
Compared to the case of LO-0, the value becomes smaller according to the increase in magnetic resistance.

Conversely, the decreased amount flows through the second adjustment magnetic circuit 9 in the form of an addition to the magnetic flux Φ2. On the other hand, Φ and a are not affected by the second adjusting magnetic circuit 9, and L ” L
It is not much different from the case where o′=,O.

Furthermore, in the state of FIG. 2(C), that is, L:L2, the magnetic gap between the adjusting iron core 8 and the second fixed yoke 6b is minimum.)
, the magnetic resistance of the second adjustment magnetic circuit 9 becomes very small,
It becomes easier for magnetic flux to pass through. That is, L: L,=,O,
When L==L, Φ2 becomes maximum compared to when L==L. On the other hand, Φ1b
In this case, the distance between the fixed adsorption body 2 and the adjusting iron core 8 becomes very narrow, and the magnetic resistance of the first adjusting magnetic circuit 13 becomes very narrow.
becomes the minimum, and Φ1b becomes close to zero. Then, the decreased amount is added to Φ2 and flows through the second adjustment magnetic circuit 9.

Furthermore, a part of the magnetic flux Φ1a flowing through the shunt magnetic circuit 12 is affected by the fact that the magnetic resistance of the second adjusting magnetic circuit 9 has become very small, making it easier for the magnetic flux to pass through, and flows in a form that is in addition to Φ2, so that Φ1a becomes L:LO! -io, L:L,
Time and space also become smaller.

In addition, in order to ensure this kind of operation, the fixed adsorbent 2
By providing the insertion hole 2a, the magnetic path cross-sectional area establishes a relationship with the cross-sectional area of the insertion hole 2a such that the magnetic flux passing through the fixed adsorption body 2 changes or decreases compared to the case without the insertion hole 2a. Must be.

Here, details of the above-mentioned magnetic flux change will be explained below using the drawings. The magnetic flux under each condition is, for example, Φ when L=L1,
It shall be written as b(L,).

In FIGS. 3(A) to 3(D), the vertical axis represents the magnetic flux under each condition, and the horizontal axis represents the amount of insertion of the adjusting iron core 8 into the fixed adsorption body 2.

A solid line 18 in FIG. 3(A) shows a change in magnetic flux 1a of the shunt magnetic circuit 12, and as L increases, LD%
, Φ1a hardly changes, but it decreases sharply between L1 and L2. Φ＋? From L(La) to Φ, a(L
The amount of decrease up to 2) will flow as part of the magnetic flux Φ2 as shown by a dashed-dotted line 2o in FIG. 3(C), which will be described later.
This results in an increase in Φ2.

Next, the solid line 19 in FIG. 3(B) indicates the first adjustment magnetic circuit 13.
It shows the change in magnetic flux Φ1b of L+: LO#0
It reaches its maximum at , and decreases as the value increases thereafter. Φ
, the amount of decrease from b(Lo) to Φ1b(L2) is.

As before, it becomes a part of Φ2 as shown by the dotted line 21 in FIG. 3(C).

The solid line 22 in FIG. 3(C) indicates the magnetic flux Φ of the second adjustment magnetic circuit 9.
2, which is the sum of the above-described one-dot chain line 2Q indicating the decrease in Φ1a and the dotted line 21 indicating the decrease in Φ,b.

Furthermore, the solid line 23 in FIG. It becomes something.

Note that the sum of Φ1 and Φ2 is the total Φ due to the permanent magnet 1, as shown in Figure 3 (C:) and (D).
As can be understood from the above, it is assumed that Φ1 and Φ2 have no leakage magnetic flux to other parts, so Φ=Φ1+Φ2 becomes constant.

Now, as described above, this embodiment has a movable iron core 3 and a fixed adsorption body 2.
The magnetic flux Φ1 of the magnetic circuit 6 that determines the attraction and holding force F between
It is shown that the adjustment can be made by changing the insertion iL of the adjusting iron core 8 in a manner as shown in FIG. 3(D). Moreover,
The relationship between L and Φ1 becomes almost linear. In other words, since the relationship between the insertion amount and the change in the adsorption/holding force F is approximately linear, this means that the relationship with the operating voltage V is also approximately linear.

In Fig. 4, the horizontal axis represents the insertion IL, and the vertical axis represents the operating voltage V.
, which shows the relationship between the insertion gauge and the operating voltage V in this embodiment. As can be understood from the figure, in this embodiment, even if the required adjustment of the operating voltage V is as low as from vl to v2, or conversely, even if the necessary adjustment of the operating voltage V is as high as from v5 to vl, with the same width as vl to v2, the insertion The regulatory landscape for weighing has hardly changed. Moreover, unlike the conventional example, the operating voltage V does not change significantly even if the 5 dimensions change slightly, so even if there is play in the threaded part of the adjusting iron core 8, the operating voltage V will change. will almost never be seen.

Note that it is possible for the lower end of the adjusting iron core 8 to protrude from the end surface of the second fixed yoke 5b, that is, to change the insertion amount to more than L:L2, but in this case, the second fixed yoke 6b and the adjusting iron core 8 Since the magnetic gap between the two and the same does not change much, the adjustment range of the operating voltage V becomes narrower, and the adjustment effect decreases. Therefore, the insertion scale is usually used at a value of about L ``Lo''; O~L=L2, which can maintain a linear relationship with the operating voltage V. On the other hand, this range is usually sufficient even if variations in component parts are included. This means that there is no need for the adjustment iron core 8 to be brought out from the second fixed yoke 5b as in the conventional example, and the adjustment position of the adjustment iron core 8 changes due to external force, causing the characteristics of the operating voltage V to change. It also prevents change.

In addition, if adjustment within the above adjustment range is not possible, it can be handled in combination with a method of changing the repulsive force f of the compression spring 11.

Effects of the Invention As described above, the present invention changes the magnetic resistance of the first adjustment magnetic circuit and the second adjustment magnetic circuit simultaneously by changing the insertion amount of the adjustment iron core into the fixed adsorption body, and as a result, the magnetic resistance of the first adjustment magnetic circuit and the second adjustment magnetic circuit are changed. The magnetic flux passing through the iron core and the fixed adsorption body is adjusted to change, and the correlation between the magnetic flux and the insertion amount is made linear. This is to make the correlation between the insertion amount and the operating voltage of the self-holding type Renoid linear, and has the effect that adjusting the insertion amount makes it very easy to adjust the operating voltage.

Furthermore, the range in which the relationship between the insertion amount and the operating voltage changes rapidly is eliminated, and it becomes possible to prevent the operating voltage characteristics from changing due to rattling of the adjusting iron core.

It also prevents the application of external force to the adjustment iron core, increasing the reliability of the operating voltage characteristics.

Ru.

[Brief explanation of the drawing]

Fig. 1 is a cross section (2) showing the schematic structure of an electromagnetic actuator according to an embodiment of the present invention, Fig. 2 is a sectional view of the vicinity of the fixed adsorption body in Fig. 1, and Fig. 3 is the insertion amount of the adjusted iron core. Figure 4 is a diagram showing the operating voltage and the insertion amount of the adjusting iron core, Figure 5 is a sectional view showing the schematic structure of a conventional electromagnetic actuator, Figure 6 This figure is a sectional view showing the vicinity of the fixed adsorbent in FIG. 5, and FIG. 7 is a diagram showing the relationship between the gap e between the adjustable iron core and the fixed adsorbent and the operating voltage. 1... Permanent magnet, 2... Fixed adsorption body,
3...Movable iron core, e...Magnetic circuit, 8
...Adjustment iron core, 9...Second adjustment magnetic circuit, 13...First adjustment magnetic circuit. Name of agent: Patent attorney Toshio Nakao and one other person
−1≦q≧≧ρ5? - Utazo 1 body 1st Figure 3 - Possible v5 Kinmo, 54-% Tm 5-1 2nd Enyu Tsukuku\ 6 - Jk% [ll (/I) (B N
(C) 3rd figure 1-→-ri 3rd ward 1--L 4th figure

Claims (1)

[Claims] A magnetic circuit formed between a permanent magnet, a fixed adsorption body into which an adjustment iron core is inserted, a movable iron core, and a fixed yoke, and an electromagnetic coil that excites this magnetic circuit, and a portion of the magnetic circuit that passes through the fixed adsorption body. is divided into a branch magnetic circuit that passes through the fixed adsorbent itself and a first adjusting magnetic circuit that passes from the fixed adsorbent at one end through the adjusting iron core and back through the fixed adsorbent, and does not include the movable iron core. An electromagnetic actuator in which a second adjusting magnetic circuit is provided between the fixed adsorption body, the adjusting iron core, the fixed yoke, and the permanent magnet.