JP2020165446A - Actuator and valve equipped with the same - Google Patents

Abstract

To provide an actuator capable of reducing power consumption and energy loss, and a valve equipped with the same.SOLUTION: An actuator 8 reciprocating a transmission member 24 includes: a fixed core 30 having magnetic material; a movable core 40 oppositely disposed to the fixed core 30 in a reciprocating direction of the transmission member 24, connected with the transmission member 24, and having magnetic material; and a coil 50 wound around either one of the fixed core 30 and the movable core 40. The magnetization direction of the fixed core 30 or the movable core 40 having smaller coercive force is inverted by the electric current flowing through the coil 50, and the transmission member 24 is moved together with the movable core 40.SELECTED DRAWING: Figure 1

Description

The present invention relates to an actuator and a valve including the actuator.

Patent Document 1 discloses an electromagnetic valve including a solenoid and a valve body that opens and closes a flow path to control the flow of fluid flowing out from an inflow port to an outflow port. The solenoid includes a plunger that is movably arranged in a direction in which the fixed iron core and the fixed iron core are separated from each other, and a coil that arranges the fixed iron core and the plunger inside. Further, the fixed iron core houses a coil spring that urges the plunger toward the valve body side.

In the solenoid, in other words, in the valve actuator, the plunger is moved by the coil spring in a direction away from the fixed iron core when the coil is not excited, and at this time, in the valve body, the valve portion is seated on the valve seat. The valve is closed. On the other hand, when the coil is excited, the plunger moves in a direction approaching the fixed iron core, so that the valve portion is separated from the valve seat to open the inflow port of the valve body, and the valve is opened.

JP-A-2009-257438

In the case of the solenoid valve, the coil is excited by passing an electric current to form a magnetic field, and the fixed iron core is magnetized to form an electromagnet. When such an electromagnet is formed, the coil must be continuously energized in order to excite the coil and maintain the valve open state. Therefore, in the case of the above-mentioned solenoid valve, if the valve opening time is long, the power consumption increases and energy loss occurs.

The present invention has been made in view of such a problem, and an object of the present invention is to provide an actuator capable of reducing power consumption and energy loss, and a valve provided with the actuator.

In order to achieve the above object, the actuator of the present invention is an actuator that reciprocates a transmission member, and is arranged so as to face a fixed core having a magnetic material and the fixed core in the reciprocating direction of the transmission member, and the transmission member is connected. A movable core having a magnetic material and a coil wound around either the fixed core or the movable core are provided, and a current is passed through the coil to allow the fixed core and the movable core to have a smaller coercive force. The magnetization direction of the is reversed, and the transmission member moves together with the movable core.

Further, the valve of the present invention includes the actuator described above, and the transmission member is a stem that reciprocates to open and close the valve body.

According to the present invention, it is possible to realize an actuator capable of reducing power consumption and thus energy loss, and a valve provided with the actuator.

It is a vertical sectional view at the time of valve closing of the valve provided with the actuator which concerns on 1st Embodiment of this invention. It is a vertical sectional view at the time of opening a valve of FIG. It is a top view of the drive mechanism of the actuator of FIG. It is a perspective view of the drive mechanism when the valve of FIG. 1 is a valve closed state. It is a perspective view of the drive mechanism when the valve of FIG. 1 is a valve open state. It is a perspective view when the valve of the drive mechanism of the actuator which concerns on 2nd Embodiment of this invention is a valve closed state. It is a perspective view of the stem of FIG. It is a perspective view when the valve of the drive mechanism of FIG. 6 is in a valve open state.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<First Embodiment>
FIG. 1 shows a vertical cross-sectional view of a valve provided with the actuator according to the first embodiment of the present invention when the valve is closed, and FIG. 2 shows a vertical cross-sectional view of the valve when the valve is opened. In the following description, for convenience, the description will be based on the vertical and horizontal directions in each figure, but this direction changes depending on the actual valve installation situation.

The valve 1 is, for example, a direct touch type metal diaphragm valve, and includes a body 2, a diaphragm (valve body) 4, a diaphragm retainer 6, an actuator 8, and the like. The valve 1 can control a minute flow rate of the process fluid with high accuracy, and is used in, for example, a semiconductor manufacturing apparatus.

The body 2 is made of a metal material such as stainless steel, and a fluid inlet 10 and a fluid outlet 12 are formed in a lower portion of the body 2. A valve chamber 14 having a concave cross section is formed in the upper part of the body 2 so as to communicate with the fluid inlet 10 and the fluid outlet 12 and open upward. In the valve chamber 14, a tubular side wall that separates the valve chamber 14 and the fluid inlet 10 is integrally formed with the body 2, and the upper end portion of the side wall functions as a valve seat 16. An annular step portion 18 is formed on the upper portion of the inner peripheral surface of the valve chamber 14.

The actuator 8 includes a case 20 in which a drive mechanism 9 is built. The case 20 has a bottomed tubular cap shape at the top and a tubular bonnet portion 22 at the bottom. The bonnet portion 22 is airtightly joined to the upper opening of the body 2 by fitting or the like to partition the valve chamber 14 in the body 2. A stem (transmission member) 24 is arranged in the bonnet portion 22 so as to be able to move up and down, in other words, to move back and forth. The stem 24 is made of a non-magnetic material such as an aluminum material.

The actuator 8 generates power to reciprocate the stem 24 by operating the drive mechanism 9, and transmits this power to the body 2 side via the stem 24. Therefore, hereinafter, the stem 24 is positioned as a power transmission member generated by the actuator 8 and is treated as one component of the actuator 8.

A diaphragm retainer 6 is fitted on the lower surface of the stem 24. The diaphragm retainer 6 is made of, for example, a synthetic resin, and can come into contact with the upper surface of the diaphragm 4 in the radial center. The diaphragm 4 is arranged above the valve seat 16 and is composed of one or a plurality of diaphragms in a dish shape whose radial center is curved upward in a natural state.

The diaphragm 4 has an ultra-thin thickness and is formed of a metal material such as stainless steel or other shape memory alloy. When joining the actuator 8 and the body 2, the lower surface of the bonnet portion 22 is pressed toward the step portion 18 while sandwiching the peripheral edge portion of the diaphragm 4. As a result, the diaphragm 4 is sandwiched and fixed by the bonnet portion 22 and the step portion 18, and the airtightness of the valve chamber 14 is ensured.

Here, in the actuator 8 of the present embodiment, a drive mechanism 9 including a fixed core 30, a movable core 40, and a coil 50 is housed in a case 20. The fixed core 30 and the movable core 40 have a rod shape extending in the radial direction X of the valve 1 and the actuator 8, are magnetic bodies, and have a permanent magnet portion. More specifically, the permanent magnet portion of the fixed core 30 is formed of an alnico magnet, and the permanent magnet portion of the movable core 40 is formed of a neodymium magnet.

The fixed core 30 is arranged in the upper part of the case 20, and the movable core 40 is arranged in the elevating direction of the stem 24, in other words, in the reciprocating direction Y, facing the lower side of the fixed core 30. The stem 24 has a T-shaped cross section, and a housing hole 26 for the movable core 40 is penetrated in the radial direction X at the upper portion extending in the radial direction X. By inserting and fixing the movable core 40 into the accommodating hole 26, the movable core 40 and the stem 24 can reciprocate in a state of being integrally connected.

The coil 50 is formed by winding the electric wire 52 around the fixed core 30, and the electric wire 52 is pulled out from the opening 20a of the upper wall of the case 20 and is electrically connected to the power supply unit 54. The power supply unit 54 can supply power to the coil 50 and reverse the direction of the current flowing through the coil 50 by switching a switch (not shown) or the like to energize the coil 50 in the opposite direction.

A yoke 60 is magnetically connected to the fixed core 30 so as to face the fixed core 30 with a movable core 40 in the reciprocating direction Y. That is, the yoke 60 is made of a soft magnetic material, for example, pure iron or low carbon steel having few impurities. A magnetic flux path (magnetic path) connected to the fixed core 30 is formed in the yoke 60, and the yoke 60 and the fixed core 30 form one magnetic circuit. By providing the yoke 60, leakage of magnetic flux from the fixed core 30 to the atmosphere is suppressed.

More specifically, the fixed core 30 has a first fixed portion 32 forming one end side of the fixed core 30 (left end side as seen in FIGS. 1 and 2) and the other end side of the fixed core 30 (in FIGS. 1 and 2). It has a second fixing portion 34 forming (on the right end side when viewed), and an alnico magnet is arranged between these portions. The yoke 60 has a first yoke portion 62 extending from the first fixing portion 32 and a second yoke portion 64 extending from the second fixing portion 34. The first and second fixing portions 32 and 34 are formed of the same material as the first and second yoke portions 62 and 64, that is, pure iron and low carbon steel described above.

The first yoke portion 62 is arranged to face the second fixed portion 34 with the movable core 40 in the reciprocating direction Y. The second yoke portion 64 is arranged to face the first fixed portion 32 with the movable core 40 in the reciprocating direction Y. On the other hand, the movable core 40 has a first movable portion 42 forming one end side of the movable core 40 (left end side as seen in FIGS. 1 and 2) and the other end side of the movable core 40 (as seen in FIGS. 1 and 2). It has a second movable portion 44 forming (on the right end side), and a neodymium magnet is arranged between these portions.

FIG. 3 shows a top view of the drive mechanism 9 of the actuator 8 as viewed from above of FIG. 1, FIG. 4 shows a perspective view of the drive mechanism 9 when the valve 1 is closed, and FIG. 5 shows a perspective view of the valve 1. The perspective view of the drive mechanism 9 in the valve open state is shown. The first fixing portion 32 and the first yoke portion 62 are connected to each other via a first arm portion 66 that is spirally curved along the inner peripheral surface of the case 20.

Further, the second fixing portion 34 and the second yoke portion 64 are connected to each other via a second arm portion 68 spirally curved along the inner peripheral surface of the case 20, similarly to the first arm portion 66. There is. The first and second arm portions 66 and 68 are formed of the same material as the first and second yoke portions 62 and 64, that is, pure iron and low carbon steel described above.

By instantly passing a current through the coil 50 (for example, for 0.5 seconds) by the power supply unit 54, a magnetic path passing through the fixed core 30 and the yoke 60 forms a magnetic field, and the fixed core 30 is magnetized based on this magnetic field. Will be done. Even if the energization of the coil 50 is stopped and the magnetic field is reduced, the strength of the magnetic force magnetized in the fixed core 30 does not decrease sharply along the magnetization curve at the time of magnetization, but is permanent. The magnetized state as a magnet is maintained.

Further, although the movable core 40 is pre-magnetized in a separate external magnetic field, since it is a strong magnetic body formed of a neodymium magnet, it has a larger coercive force than the fixed core 30 and the yoke 60 made of an alnico magnet. Therefore, the magnetizing direction of the movable core 40 is not reversed due to the influence of the magnetic field accompanying the energization of the coil 50.

The coercive force refers to the strength of the external magnetic field in the opposite direction required to return the magnetized magnetic material to the unmagnetized state. In this way, the fixed core 30, the yoke 60, and the movable core 40 can function as permanent magnets for utilizing the magnetic force as the driving force in the driving mechanism 9, and thus the open / closed state of the valve 1 described later can be maintained.

Specifically, the first movable portion 42 and the second movable portion 44 of the movable core 40 have different magnetic poles (N pole or S pole) P1 and P2, respectively. Further, in the case of the valve closed state shown in FIGS. 1 and 4, the first fixed portion 32 and the second fixed portion 34 of the fixed core 30 have different magnetic poles P1 and P2, respectively. Further, the first yoke portion 62 of the yoke 60 has the same magnetic pole P1 as the first fixed portion 32, and the second yoke portion 64 has the same magnetic pole P2 as the second fixed portion 34.

Therefore, in a state where the energization of the coil 50 is stopped, the magnetic path passing through the fixed core 30, the yoke 60, and the movable core 40 forms the magnetic field of the drive mechanism 9 as a whole, and the different magnetic poles P1 and P2 attract each other and attract each other. The same magnetic poles P1 and P2 repel each other to generate a repulsive force.

Therefore, in the cases shown in FIGS. 1 and 4, the first movable portion 42 (magnetic pole P1) and the second movable portion 44 (magnetic pole P2) are the second yoke portion 64 (magnetic pole P2) and the second movable portion 44 (magnetic pole P2), respectively. 1 Receives an attractive force indicated by a solid arrow from the yoke portion 62 (magnetic pole P1). On the other hand, the first movable portion 42 (magnetic pole P1) and the second movable portion 44 (magnetic pole P2) are indicated by dashed arrows from the first fixed portion 32 (magnetic pole P1) and the second fixed portion 34 (magnetic pole P2), respectively. Receive the repulsive force shown.

The movable core 40 that receives these attractive and repulsive forces is attracted to the yoke 60 as a whole and descends, and at the same time, the stem 24 also descends. As a result, the central portion of the diaphragm 4 is pressed downward by the diaphragm retainer 6, and the diaphragm 4 is deformed into a concave cross section against its own restoring force to sit on the valve seat 16, and the valve 1 is closed. It should be noted that this valve closed state is continuously maintained even after the energization of the coil 50 is stopped.

Next, when the valve closed state of FIGS. 1 and 4 is formed by the power supply unit 54, a current in the direction opposite to that when the fixed core 30 and the yoke 60 are magnetized is instantaneously applied to the coil 50 (for example, 0. (5 seconds). As a result, the directions of the magnetic paths passing through the fixed core 30 and the yoke 60 are reversed, and a magnetic field opposite to the valve closed state is formed around the fixed core 30 and the yoke 60, and the fixed core 30 is based on this magnetic field. Is magnetized.

Specifically, the first movable portion 42 (magnetic pole P1) and the second movable portion 44 (magnetic pole P2) are from the second yoke portion 64 (magnetic pole P1) and the first yoke portion 62 (magnetic pole P2), respectively. While receiving the repulsive force indicated by the broken line arrow, it receives the attractive force indicated by the solid line arrow from the first fixed portion 32 (magnetic pole P2) and the second fixed portion 34 (magnetic pole P1), respectively.

As described above, even if the energization of the coil 50 is stopped, the strength of the magnetic force magnetized on the fixed core 30 and the yoke 60 does not significantly decrease. Further, since the movable core 40 has a larger coercive force than the fixed core 30 and the yoke 60, the magnetizing direction is not reversed due to the influence of the magnetic field which is opposite to the valve closed state due to the energization of the coil 50. ..

The movable core 40 that receives these attractive and repulsive forces is attracted to the fixed core 30 as a whole and rises, and at the same time, the stem 24 also rises. That is, by passing a current through the coil 50, the direction of the magnetic path passing through the fixed core 30 on the side where the coercive force of the fixed core 30 and the movable core 40 is small is reversed, and the stem 24 moves together with the movable core 40. As a result, the diaphragm 4 is in a natural state with a convex cross section due to its own restoring force and is separated from the valve seat 16, and the valve 1 is in a valve open state. This valve open state is continuously maintained even after the energization of the coil 50 is stopped.

As described above, in the actuator 8 of the present embodiment and the valve 1 provided with the actuator 8, the fixed core 30 and the movable core 40 to which the stem 24 is connected are formed of an alnico magnet and a neodium magnet, respectively, and a current is passed through the coil 50. As a result, the direction of the magnetic path passing through the fixed core 30 having a small coercive force among the fixed core 30 and the movable core 40 is reversed, and the stem 24 moves together with the movable core 40.

As a result, the coil 50 only needs to be energized when the valve 1 is switched to the valve open state or the valve closed state, and the coil is used to maintain the valve open state or the valve closed state like a general solenoid valve solenoid. It is not necessary to keep the current flowing through 50 to form a magnetic field. Therefore, especially when either the valve open state or the valve closed state is long, the power consumption for maintaining these states can be reduced, and the energy of the actuator 8 and the valve 1 provided with the actuator 8 can be reduced. Loss can be reduced.

Further, by providing the yoke 60, it is possible to suppress leakage of magnetic flux from the fixed core 30. Further, when the valve 1 is switched to the valve open state or the valve closed state, not only the attractive force or repulsive force from the fixed core 30 can be applied to the movable core 40, but also the attractive force or repulsive force from the yoke 60 can be applied. .. Therefore, the responsiveness of the operation of the actuator 8 and the valve 1 can be enhanced, and the operation of the actuator 8 and the valve 1 can be performed more reliably, and the reliability thereof can be enhanced.

Further, when the valve is closed, the first and second movable portions 42 and 44 of the movable core 40 are not in contact with the first and second yoke portions 62 and 64. When the movable core 40 comes into contact with the first and second yoke portions 62 and 64, the transmission force from the movable core 40 to the valve seat 16, that is, the force with which the diaphragm 4 is pressed against the valve seat 16 is limited, and the valve 1 The deadline is insufficient. Therefore, by making the first and second movable portions 42 and 44 of the movable core 40 non-contact with the first and second yoke portions 62 and 64, there is no restriction on the lowering of the movable core 40, and the diaphragm 4 is a valve. It is sufficiently pressed by the seat 16 to form a valve closed state having a high sealing property, and the deadline force at the time of closing the valve 1 can be increased.

Further, by adjusting the attractive force and the repulsive force received by the movable core 40, it is possible to set the maximum lowering position of the stem 24 at the time of valve closing, in other words, the bottom dead center. Further, if the position of the fixed core 30 in the reciprocating direction Y is determined, it is possible to set the maximum rising position of the stem 24 at the time of valve opening, in other words, the top dead center.

Further, since the first and second arm portions 66 and 68 are formed by being spirally curved along the inner peripheral surface of the case 20, the outer peripheral wall of the case 20 is tubular as in the case of the present embodiment. In this case, the actuator 8 and the valve 1 can be made compact.

<Second Embodiment>
FIG. 6 shows a perspective view of the actuator drive mechanism according to the second embodiment of the present invention when the valve is in the closed state, FIG. 7 shows a perspective view of the stem of FIG. 6, and FIG. 8 is a diagram. The perspective view when the valve of the drive mechanism of 6 is in the valve open state is shown. Hereinafter, a configuration different from that of the first embodiment will be mainly described, and the description and illustration of the same configuration as that of the first embodiment may be omitted by describing the same reference numerals.

As shown in FIG. 6, the drive mechanism 70 built into the actuator 8 of the present embodiment operates in the same manner as in the case of the first embodiment, but the paired fixed cores 30A and 30B and the movable cores 40A and 40B, respectively. , 50A and 50B are provided. The fixed cores 30A and 30B are magnetically connected to the yokes 60A and 60B arranged so as to face the fixed cores 30A and 30B with the movable cores 40A and 40B separated from each other in the reciprocating direction Y, respectively.

As in the case of the first embodiment, the fixed cores 30A and 30B have the first and second fixed portions 32A and 34A and the first and second fixed portions 32B and 34B, respectively. The yoke 60A has a first yoke portion 62A extending from the first fixing portion 32A and a second yoke portion 64A extending from the second fixing portion 34A. The yoke 60B has a first yoke portion 62B extending from the first fixing portion 32B and a second yoke portion 64B extending from the second fixing portion 34B.

As shown in FIG. 7, the movable cores 40A and 40B are connected to the stem 71 in an arrangement in which the longitudinal directions are parallel to each other. As in the case of the first embodiment, the movable cores 40A and 40B have the first and second movable portions 42A and 44A and the second movable portions 42B and 44B, respectively. The first fixing portions 32A and 32B and the first yoke portions 62A and 62B in the present embodiment are connected to each other via linear first arm portions 66A and 66B inclined with respect to the reciprocating direction Y, respectively.

Further, the second fixed portions 34A and 34B and the second yoke portions 64A and 64B are linear second arm portions 68A and 68B that are inclined with respect to the reciprocating direction Y, similarly to the first arm portions 66A and 66B. They are connected to each other via. The operation of the drive mechanism 70 configured in this way is basically the same as that of the drive mechanism 9 of the first embodiment.

Specifically, in the case shown in FIG. 6, the movable cores 40A and 40B receive the attractive force indicated by the solid line arrow and the repulsive force indicated by the broken line arrow, and are attracted to the yokes 60A and 60B, respectively, and descend, and the stem 71 is combined. Also descends. As a result, the diaphragm 4 is seated on the valve seat 16, and the valve 1 is closed.

On the other hand, the power supply unit 54 instantly causes the coil 50 to flow a current in the direction opposite to that when the valve closed state of FIG. 6 is formed, so that the magnetic fields in the opposite direction to the valve closed state are fixed cores 30A and 30B. , The fixed cores 30A and 30B are magnetized based on the magnetic field formed around the yokes 60A and 60B.

As a result, as shown in FIG. 8, the movable cores 40A and 40B receive the attractive force indicated by the solid line arrow and the repulsive force indicated by the broken line arrow, and are attracted to the fixed cores 30A and 30B, respectively, to rise, and the stem 71 is combined. Also rises. As a result, the diaphragm 4 is separated from the valve seat 16 and the valve 1 is opened. This valve open state is continuously maintained even after the energization of the coil 50 is stopped.

As described above, the actuator 8 of the present embodiment and the valve 1 provided with the actuator 8 can energize the coil 50 only when the valve 1 is switched to the valve open state or the valve closed state, as in the case of the first embodiment. good. Therefore, the power consumption for maintaining the valve open state or the valve closed state can be reduced, and the energy loss of the actuator 8 and the valve 1 provided with the actuator 8 can be reduced.

Further, particularly in the case of the present embodiment, the drive mechanism 70 built in the actuator 8 includes a pair of fixed cores 30A and 30B, movable cores 40A and 40B, and coils 50A and 50B, respectively. As a result, the operations of the actuator 8 and the valve 1 can be realized by a dual system in which the operations are duplicated, so that the reliability of these can be further improved.

Further, by providing the linear first arm portions 66A and 66B and the second arm portions 68A and 68B, these are spirally curved along the inner peripheral surface of the case 20 as in the first embodiment. The lengths of the first arm portions 66A and 66B and the second arm portions 68A and 68B can be shortened as compared with the case where the first arm portions 66A and 66B are formed. As a result, the magnetic paths of the yokes 60A and 60B can be shortened, so that the responsiveness of the operation of the actuator 8 and the valve 1 can be further improved. The operation of the actuator 8 and the valve 1 can be performed more reliably, and the reliability of these can be further enhanced.

Although the description of the embodiment of the present invention is completed above, the present invention is not limited to this, and various modifications can be made without departing from the spirit of the present invention.
For example, the valve 1 is not limited to the semiconductor manufacturing apparatus, and may be used in an apparatus for other purposes. Further, the actuator 8 may drive a valve having a valve body other than the diaphragm 4. Further, the actuator 8 may drive a driving object other than the valve 1, in which case the actuator 8 transmits power to a transmission member instead of the stem 24.

Further, when the influence of magnetic flux leakage is small, the yoke 60 does not necessarily have to be provided.
Further, the fixed core 30 and the movable core 40 are not limited to the Arnico magnet and the neodium magnet, respectively, and may be formed from other permanent magnets, and can generate a magnetic force by themselves to maintain the magnetic force and have an external magnetic field. As long as the magnetic poles can be reversed, the magnet is not necessarily a permanent magnet, and a magnetic material having such characteristics may be used.

Further, the stem 24 is formed of a non-magnetic material such as an aluminum material, but the present invention is not limited to this, and the transmission member such as the stem 24 may be formed of the same or different magnetic material as the connected movable core 40. good. If the transmission member and the movable core 40 are integrally molded from the same magnetic material, the productivity of the actuator 8 is improved.

Further, the coil 50 is not limited to the fixed core 30, and may be wound around either the fixed core 30 or the movable core 40. Further, the coercive force is not limited to the fixed core 30, and any one of the fixed core 30 and the movable core 40 may be reduced. For example, by winding the coil 50 around the movable core 40 and passing an electric current through the coil 50, the direction of the magnetic path passing through the movable core 40 on the side of the fixed core 30 and the movable core 40 having a smaller coercive force is reversed. The stem 24 may move together with the movable core 40. However, it is preferable to wind the coil 50 around the fixed core 30 because there is no concern about disconnection due to tension due to the movement of the electric wire 52.

Further, the configuration of the drive mechanism of the actuator 8 is not strictly limited to the above-mentioned contents, and in addition to the fixed core 30 and the movable core 40, elasticity such as a spring for auxiliary pressing the transmission member is elastic. A member may be provided. As a result, it is possible to increase the deadline force when the valve 1 is closed.

1 valve 4 diaphragm (valve body)
8 Actuator 24 stem (transmission member)
30 Fixed core 32 1st fixed part 34 2nd fixed part 40 Movable core 50 Coil 60 Yoke 62 1st yoke part 64 2nd yoke part 66 1st arm part 68 2nd arm part

Claims (13)

An actuator that reciprocates a transmission member
A fixed core with a magnetic material and
A movable core that is arranged to face the fixed core in the reciprocating direction of the transmission member, is connected to the transmission member, and has a magnetic material.
A coil wound around either the fixed core or the movable core is provided.
An actuator in which the magnetization direction of the fixed core and the movable core on the side having a smaller coercive force is reversed by passing an electric current through the coil, and the transmission member moves together with the movable core. The actuator according to claim 1, wherein the coil is wound around the fixed core. The actuator according to claim 1 or 2, wherein the fixed core has a smaller coercive force than the movable core. The actuator according to claim 3, further comprising a yoke that is arranged to face the fixed core with the movable core in the reciprocating direction and magnetically connected to the fixed core. The fixed core
The first fixed portion forming one end side of the fixed core and
It has a second fixing portion forming the other end side of the fixing core, and has a second fixing portion.
The yoke is
A first yoke portion that extends from the first fixed portion and is arranged to face the second fixed portion with the movable core in the reciprocating direction.
The actuator according to claim 4, further comprising a second yoke portion extending from the second fixed portion and arranged to face the first fixed portion across the movable core in the reciprocating direction. The first fixing portion and the first yoke portion are connected via a first arm portion that is spirally curved along the inner peripheral surface of the case of the actuator, and the second fixing portion and the second yoke portion are connected to each other. The actuator according to claim 5, wherein the portion is connected via a second arm portion that is spirally curved along the inner peripheral surface of the case. The actuator according to any one of claims 1 to 6, wherein the transmission member is made of a non-magnetic material. The actuator according to any one of claims 1 to 7, wherein the transmission member is made of the same magnetic material as the movable core. The actuator according to any one of claims 1 to 8, wherein the fixed core and the movable core have a permanent magnet. The actuator according to claim 9, wherein the fixed core has an alnico magnet. The actuator according to claim 9 or 10, wherein the movable core has a neodymium magnet. A valve comprising the actuator according to any one of claims 1 to 11.
The transmission member is a valve that is a stem that reciprocates to open and close the valve body. 12. The valve according to claim 12, wherein the movable core is in non-contact with the first and second yoke portions and the first and second fixed portions when the valve is closed.

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