JP2005223168A - Electromagnetic actuator and control method thereof - Google Patents

Abstract

Even when a load force generated in a movable part is small, the movable part is operated at a low speed.
A control circuit included in an electromagnetic actuator includes a coil L1, an AC power supply V2, a diode 5, and switches S1 and S2. The coil L1 and the diode 5 are connected in parallel. The switch S1 is connected in series with the parallel connection of the coil L1 and the diode 5. The switch S2 is connected in parallel with the series connection of the coil L1 and the switch S1. A power source V2 is applied to both ends of the switch S2. If the switch S2 is also closed while the switch S1 is closed, it becomes difficult for current to flow to the switch S1 side where the impedance of the coil L1 exists, and the supply of current to the coil L1 is almost cut off. At this time, since the switch S1 is in the closed state, it is possible to prevent the current from returning in the loop circuit formed by the coil L1 and the diode 5.
[Selection] Figure 16

Description

  The present invention relates to an electromagnetic actuator and a control method thereof, and can be applied to, for example, a vacuum circuit breaker.

  Conventionally, an electromagnetic actuator generates an electromagnetic force in a coil by supplying a current to the coil, for example, and operates a movable part by the electromagnetic force. The electromagnetic actuator is used for opening and closing a vacuum valve provided in a vacuum, for example, in a vacuum circuit breaker.

  Non-Patent Documents 1 and 2 introduce the relationship between the magnetic field generated in the coil and the operation of the electromagnetic actuator in a vacuum circuit breaker including, for example, an electromagnetic actuator.

Edgar Dullni, two others, "A Vacuum Circuit-Breaker with Permanent Magnetic Actuator and Electronic Control", 15th International Conference and Exhibition on Electrical Power Distribution Engineering, CIRED, 1999 Year Edgar Dullni and three others, “A Family of Vacuum Circuit-Breakers with Worldwide Applications Using Common Components ”, 17th International Conference and Exhibition on Electrical Power Distribution Engineering, CIR CIRED, 2001

  Along with the operation of the movable part of the electromagnetic actuator, a load force is generated in the movable part at the time of starting the operation and at the time of acting on the vacuum valve in the vacuum circuit breaker, for example. That is, the load force generated in the movable part changes with respect to the operation time.

  Conventionally, a current is constantly supplied to the coil from the start to the end of the operation of the electromagnetic actuator. For this reason, when the load force which arises in a movable part is small, a movable part accelerates excessively. For example, in a vacuum circuit breaker, since a high voltage is applied between the contact points of the valve, the contacts repeatedly bounce when contacted at a high speed, and the contacts may be welded by an arc generated between the contact points. In addition, when the contact contacts at a high speed, a strong impact is generated, and the contact portion may be deformed by the impact.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to operate a movable part at a low speed even when a load force generated in the movable part is small.

  The first electromagnetic actuator control method according to the present invention includes a coil, a power source that supplies current to the coil, a movable part that moves by electromagnetic force generated by the coil, and a switch connected in series to the coil. First, the switch is opened at a first time when a first predetermined period has elapsed after the start of energization of the coil. Thereafter, the switch is closed at a second time point and opened after a second predetermined period has elapsed from the second time point. The time change of the load force generated in the movable part is obtained in advance, and the first time point is a time point when the absolute value of the load force becomes a first predetermined value in the process of decreasing. The second time point is a time point that is traced back by a third predetermined period from the time point when the absolute value of the load force increases in the course of increasing the second predetermined value.

  The second electromagnetic actuator control method according to the present invention includes a coil, a power source that supplies current to the coil, a movable part that moves from a starting point to an end point by an electromagnetic force generated by the coil, and a serial connection to the coil. In an electromagnetic actuator provided with a switch to be connected, first, a time change of a load force generated in the movable part in a period from the start point to the end point of the movable part is obtained in advance. The time change of the electromagnetic force generated by the coil is determined by incrementing the load force over time by a predetermined force. A time change of the current flowing in the coil is obtained to obtain a time change of the electromagnetic force. A rectangular pulse is obtained by converting the time change of the current by a pulse width modulation method. The switch opens and closes according to the value of the rectangular pulse.

  A third electromagnetic actuator control method according to the present invention includes a coil, a power source for supplying current to the coil, a movable part that moves by electromagnetic force generated by the coil, and a switch connected in series to the coil. First, after the energization of the coil is started, the switch is opened when the movable part moves a first predetermined distance. Thereafter, the switch is closed when the movable part moves a second predetermined distance. Then, the switch is opened when a predetermined period elapses after the movable portion moves the third predetermined distance. The movement of the movable part, wherein a change in the moving distance of the load force generated in the movable part is obtained in advance, and the first predetermined distance becomes a first predetermined value in the process of decreasing the absolute value of the load force. Is the distance traveled since the start of. The second predetermined distance becomes a second predetermined value in the process of increasing the absolute value of the load force. The second predetermined distance goes back by a fourth predetermined distance from the moving distance from the start of the movement of the movable part. Travel distance. The third predetermined distance is a movement distance from the time when the movable part starts to move when the movable part 1 reaches the end point.

  A first electromagnetic actuator according to the present invention includes a coil, a movable part, a first switch, and a second switch. The movable part is operated by an electromagnetic force generated by the coil. The first switch is connected in series with a diode connected in parallel to the coil and a parallel connection of the coil and the diode. The second switch is connected in parallel to the series connection of the coil and the first switch, and a voltage is applied to both ends thereof.

  A second electromagnetic actuator according to the present invention includes a coil, a power source that supplies current to the coil, and a movable part that operates by electromagnetic force generated by the coil. The power source includes a first capacitor, a second capacitor, a first thyristor, and a second thyristor. The first capacitor and the first thyristor are connected in series with each other. The second capacitor and the second thyristor are connected in parallel to the series connection of the first capacitor and the first thyristor, and are connected in series to each other.

  A third electromagnetic actuator according to the present invention includes a coil, a power source that supplies current to the coil, a movable part that operates by electromagnetic force generated by the coil, and a switch connected in series to the coil. . The power source includes a capacitor and a thyristor connected in series with each other.

  According to the first electromagnetic actuator control method of the present invention, after the start of energization, the current flowing through the coil is interrupted when the absolute value of the load force generated in the movable part becomes equal to or lower than the first predetermined value, A current is passed through the coil from a third predetermined period before the second predetermined value or more. Thereby, the difference between the load force and the electromagnetic force is reduced, and the movable portion can be operated at a low speed even when the load force generated in the movable portion is small. Therefore, the operation of the movable part is stabilized. In addition, since a period during which no current flows through the coil is provided, the efficiency of the electromagnetic actuator is improved.

  According to the second electromagnetic actuator control method of the present invention, the current flowing in the coil can be controlled with high accuracy, and a desired electromagnetic force can be generated. Therefore, the operation of the movable part is stabilized and the efficiency of the electromagnetic actuator is improved.

  According to the third method for controlling an electromagnetic actuator according to the present invention, since the current flowing through the coil is controlled based on the position of the movable part, the time during which the load force is generated in the movable part and the time during which the coil generates the electromagnetic force The deviation can be reduced. Therefore, the operation of the movable part can be controlled with high accuracy.

  If the first switch is switched from the closed state to the open state when there is no second switch, the current is fed back in the loop circuit formed by the coil and the diode, and the switching responsiveness is lowered. According to the first electromagnetic actuator of the present invention, the second switch is provided, and the current is fed back in the loop circuit by closing the second switch while the first switch is closed instead of opening and closing the first switch. Without interrupting the current flowing in the coil. That is, switching responsiveness can be improved.

  According to the second electromagnetic actuator of the present invention, after the first thyristor and the second thyristor are turned on, the first capacitor and the second capacitor are discharged. Thereafter, the current flowing from the capacitor C1 and the capacitor C2 becomes small, and the first thyristor and the second thyristor are automatically turned off. Therefore, the current flowing through the coil can be controlled only by controlling the timing of closing the first thyristor and the second thyristor.

  According to the third electromagnetic actuator of the present invention, a large electromagnetic force can be generated by the coil by causing a current larger than that of the power source for charging the capacitor to flow through the coil.

  For example, a vacuum circuit breaker to which the electromagnetic actuator and the control method thereof according to the present invention can be applied is shown as a sectional view in FIG. The vacuum circuit breaker includes an electromagnetic actuator 100, a connection unit 101, and a vacuum circuit breaker 104.

  The electromagnetic actuator 100 includes an iron core 4, coils L <b> 1 and L <b> 2, a permanent magnet 2, a movable part 1, and a nonmagnetic material 13. The iron core 4 has a cylindrical shape with both ends closed, extends in the direction of the shaft 110, and has a convex portion on the inner surface near the center with respect to the direction of the shaft 110. The permanent magnet 2 is placed on a surface parallel to the shaft 110 of the surface of the convex portion. Coils L <b> 1 and L <b> 2 are provided in a concave portion formed by the convex portion and both ends of the iron core 4. The coil L1 is provided in the concave portion on the connection portion 101 side, and the coil L2 is provided in the concave portion on the side opposite to the concave portion in which L1 is provided. The movable portion 1 is configured by connecting shaft fixing portions 12 a and 12 b in the direction of the shaft 110 via a magnetic body 11. The magnetic body 11 can move in the direction of the axis 110 inside the iron core 4. Both ends of the iron core 4 are penetrated by the shaft fixing portions 12a and 12b at positions where the shaft 110 penetrates.

  The non-magnetic body 13 is provided inside the end surface of the iron core 4 on the shaft fixing portion 12b side, and the magnetic body 11 moves toward the end surface side of the iron core 4 on the shaft fixing portion 12b side in the direction of the shaft 110. Hinder. FIG. 1 shows a state where the vacuum valve 103 is opened. The movable part 1 is at a limit position where it can move to the coil L2 side, and can be regarded as a starting point. Thereby, when the movable part 1 is located at the starting point, the load force by the permanent magnet generated in the movable part 1 is movable at a position where the movable part 1 comes into contact with the end surface of the iron core 4 when there is no non-magnetic material 13. It becomes smaller than the load force by the permanent magnet which arises in the part 1. FIG. Providing the non-magnetic material 13 is desirable because the electromagnetic force necessary for starting the movement of the movable portion 1 becomes small.

  The shaft fixing portion 12a on the coil L1 side is connected to the connection portion 101 so as to be movable in the direction of the shaft 110. The connection unit 101 is connected to a vacuum valve 103 provided in the vacuum cutoff unit 104 via a spring 102. The spring 102 can be expanded and contracted in the opening / closing direction of the vacuum valve 103. The connecting portion 101 functions as a crank that transmits the movement of the movable portion 1 along the axis 110 to the vacuum valve 103 via the spring 102. In FIG. 1, the connecting portion 101 causes the vacuum valve 103 to move in the direction opposite to the moving direction of the movable portion 1 as the movable portion 1 moves along the axis 110.

  By passing an electric current through the coil L1 and generating an electromagnetic force on the magnetic body 11, the magnetic body 11 moves to the coil L1 side in the direction of the shaft 110, and the vacuum valve 103 is connected via the connection portion 101 and the spring 102. Close. After the vacuum valve 103 is closed, the spring 102 is compressed, and the movable part 1 reaches a limit position where it can move to the coil L1 side. This position can be regarded as the end point of the movable part 1.

  In the following embodiment, a method for controlling the electromagnetic force generated by the coil 11 in the magnetic body 11 and a control circuit used for the control will be described.

Embodiment 1 FIG.
FIG. 2 conceptually shows a control circuit included in the electromagnetic actuator 100 according to the present embodiment. The control circuit includes a coil L1, a power supply V1, a diode 5, and a switch S1. The coil L1 corresponds to the coil L1 shown in FIG.

  The coil L1 and the diode 5 are connected in parallel. The switch S1 is connected in series with the parallel connection of the coil L1 and the diode 5. The power source V1 is connected to both ends of the parallel connection of the coil L1 and the diode 5 via the switch S1. The switch S1 can be opened and closed, and for example, a semiconductor switch can be adopted.

  The power source V1 is, for example, direct current, and back electromotive force is generated at both ends of the coil L1 when the switch S1 is opened. The diode 5 prevents the switch S1 from being damaged by this counter electromotive force. In the case where back electromotive force is not a problem when the switch S1 is opened, the diode 5 may not be provided.

  First, the time change of the energy of the magnetic circuit formed by the permanent magnet 2 and the iron core 4 and the load force (hereinafter simply referred to as “load force”) generated in the movable part 1 due to the repulsion of the spring 102 is obtained. FIG. 3 shows a time change of the load force generated in the movable part 1 by a curve 201. The force generated in the movable portion 1 shown in FIG. 3 is positive in the direction from the shaft fixing portion 12a of the shaft 110 to the shaft fixing portion 12b (the direction of the arrow attached to the shaft 110 in FIG. 1). Hereinafter, in any embodiment, the force generated in the movable portion 1 is positive in the same direction. The direction from the shaft fixing portion 12 a of the shaft 110 toward the shaft fixing portion 12 b is the direction of the shaft 110.

  The time change of the load force can be obtained by calculation from design values of the spring 102 and the permanent magnet 2 constituting the electromagnetic actuator 100, for example. Before the time T0, the movable part 1 is located at the starting point, and the movable part 1 starts to move in the direction of the shaft 110 from the time T0 by the electromagnetic force generated from the coil 1. When the movable part 1 is in the vicinity of the starting point, the load force generated by the magnetic circuit formed by the permanent magnet 2 and the iron core 4 acts in the direction of the axis 110 (that is, the direction opposite to the direction in which the movable part 1 moves). When the movable part 1 is located at the starting point (before time T0), the load force is substantially constant, and after the movable part 1 starts to move (from time T0), the load force decreases. The load force generated from the time point T2 is a repulsive force when the spring 102 is compressed by the movement of the movable part 1 after the vacuum valve 103 is closed, and is the direction opposite to the direction in which the spring 102 is compressed, that is, the movable part. For 1, this occurs in the direction of the axis 110. At time T2, a load force due to an impact when the vacuum valve 103 is closed may be generated. The load force generated from time T2 shown in FIG. 3 may include the load force generated when the vacuum valve 103 is closed, as well as the load force due to the spring 102.

  After time T3, the movable part 1 is located at the end point. When the movable part 1 is in the vicinity of the end point, in addition to the load force due to the compression of the spring 102, a load force due to the magnetic circuit formed by the permanent magnet 2 and the iron core 4 is generated in a direction opposite to the direction of the shaft 110. This is because the magnetic body 11 functions as a magnetic yoke between the end of the iron core 4 on the connection portion 101 side and the permanent magnet 2. The magnitude of the load force due to the magnetic circuit created by the permanent magnet 2 and the iron core 4 is greater than the magnitude of the load force due to compression of the spring 102. For this reason, when the movable part 1 is located at the end point, it can remain at the end point even if no force is applied from the outside. When the movable part 1 is located at the end point, the load force is substantially constant.

Based on the load force curve 201, time points T ^* 0, T1, T2, T3, T ^* 2, and T ^* 3 are set. At the time point T1, the movable unit 1 is not pulled back to the starting point side even when the supply of power to the coil L1 is stopped at the time point T1, as will be described later, while the movable unit 1 is moving toward the end point side. At time T <b> 2, the vacuum valve 103 is closed, and the movable part 1 starts to compress the spring 102 via the connection part 101. At the time T3, the movable part 1 reaches the end point.

When an electromagnetic force is generated in the magnetic body 11 by the coil L1, the electromagnetic force increases after a current starts to flow through the coil L1, and reaches a predetermined value after a predetermined period. For this reason, in order to start moving the movable part 1 from the time T0, the magnitude of the electromagnetic force needs to be larger than the magnitude of the load force at the time T0. Therefore, only the interval τ1 from start of generation electromagnetic force to the magnitude of the electromagnetic force is greater than the magnitude of the load force, to set the time T ^* 0 predated from time T0, the coil from time T ^* 0 as described below It is desirable to start generating electromagnetic force in L1. In other words, the movable part 1 starts to move after the interval τ1 after the electromagnetic force is generated in the coil L1.

Further, the electromagnetic force may start to be generated in the coil L1 at the time T2, but the energy of the electromagnetic force is smaller than the difference between the repulsive energy due to the compression of the spring 102 and the kinetic energy of the movable part 1, and the movable part 1 is the starting point. May be pushed back to the side. Therefore, to set the time T ^* 2 from time T2 to a predetermined time period [Delta] T ^* 2 before, it is desirable to begin to generate an electromagnetic force from the time T ^* 2 in the coil L1 as described below. Thereby, the energy of the electromagnetic force at time T2 can be made larger than the difference between the two energies.

The generation of electromagnetic force by the coil L1 may be terminated at the time T3 when the movable part 1 reaches the end point, but due to the repulsive force generated when the movable part 1 collides with the end surface of the iron core 4 on the shaft fixing part 12a side, There is a possibility that the movable part 1 is pushed back to the starting point side. Therefore, it is desirable to set a time point T ^* 3 at which the predetermined period τ2 has elapsed from the time point T3, and to end the generation of the electromagnetic force by the coil L1 at the time point T ^* 3 as described later.

Next, the opening / closing control of the switch S1 according to the above-described time points T ^* 0, T1, T ^* 2, and T ^* 3 will be described. FIG. 4 conceptually shows the time change of opening / closing (on / off) of the switch S1. Switch S1 is closed at time T ^* 0 and opened at time T1, and then closed at time T ^* 2 and opened at time T ^* 3. The time change of the electromagnetic force generated by the coil L1 when the switch S1 is opened and closed according to FIG. 4 is conceptually shown by a curve 202 in FIG. 5, for example. The absolute value of the electromagnetic force is shown, but its direction is always opposite to the direction of the axis 110.

After the switch S1 is opened at time T ^* 3, the electromagnetic force generated by the coil L1 decreases and becomes smaller than the magnitude of the repulsive force of the spring 102. However, since the load force by the permanent magnet 2 works in the direction opposite to the direction of the axis 110 as described above, the movable portion 1 remains at the end point.

Time point T1 is the first time point, time point T ^* 2 is the second time point, time period T1 from time point T ^* 0 to time point T1 is the first predetermined time period, time period T2 from time point T ^* 2 to time point T ^* 3 is the second time period The above-mentioned electromagnetic actuator control method can be grasped as follows. That is, the switch S1 is opened at the first time point T1 when the first predetermined period ΔT1 has elapsed after the start of energization of the coil L1 (T ^* 0). Thereafter, the switch S1 is closed at a second time point T ^* 2, the second predetermined time period ΔT2 is opened after a lapse (T ^* 3) from the second time point T ^* 2.

Further, the absolute value of the load force f1 generated in the movable part 1 when the movable part 1 is not pulled back to the starting point side even if the switch S1 is opened during the movement of the movable part 1 to the end point side. It is grasped as the first predetermined value. Among the load forces generated in the movable part 1 by the compression of the spring 102, the absolute value of the load force f2 at the initial stage of the compression of the spring 102 is grasped as a second predetermined value. FIG. 3 shows a case where the load forces f1 and f2 are equal. Furthermore, if the period ΔT ^* 2 is grasped as the third predetermined period, the first time point T1 and the second time point T ^* 2 can be grasped as follows.

That is, the first time point T1 is a time point when the first predetermined value | f1 | is reached in the process in which the absolute value of the load force decreases. The second time point T ^* 2 is a time point that is back by the third predetermined period ΔT ^* 2 from the time point T2 at which the second predetermined value | f2 | is reached in the process of increasing the absolute value of the load force.

According to the opening / closing control of the electromagnetic actuator control method described above, the current flowing through the coil L1 when the absolute value of the load force generated in the movable part 1 becomes equal to or less than the first predetermined value after energization is started. And a current is passed through the coil L1 before the third predetermined period ΔT ^* 2 of the time point T2 when the value becomes equal to or greater than the second predetermined value. Thereby, the difference between the load force and the electromagnetic force is reduced, and the movable portion 1 can be operated at a low speed even when the load force generated in the movable portion 1 is small. Therefore, the operation of the movable part 1 is stabilized. Further, since a period (time T1 to time T ^* 2) during which no current flows through the coil L1 is provided, the efficiency of the electromagnetic actuator 100 is improved.

Embodiment 2. FIG.
In the present embodiment, the switch S1 is controlled by a control method different from that in the first embodiment using the same control circuit (FIG. 2) as in the first embodiment. FIG. 6 is a flowchart showing steps for deriving a rectangular pulse used to open and close the switch S1.

  1stly, the time change of the load force which arises in the movable part 1 in the period from the movable part 1 to an end point is calculated | required previously. However, after the movable part 1 reaches the end point, the time change from the end point until the predetermined period τ2 elapses may be obtained so that the movable part 1 is not pushed back to the start point side.

  Secondly, the time change of the electromagnetic force generated by the coil L1 is determined by incrementing the load force by a predetermined force. FIG. 7 conceptually shows a curve 203 representing the time change of the electromagnetic force generated by the coil L1 derived in the second step. The predetermined force that is incremented need not be constant.

  Thirdly, the time change of the current flowing through the coil L1 is obtained so that the time change (curve 203) of the electromagnetic force derived in the second step can be obtained. The time change of the current is obtained by calculation from the design value of the electromagnetic actuator, for example.

  Fourth, a rectangular pulse is obtained by converting the time conversion of the current obtained in the third step by a pulse width modulation (PWM) method. FIG. 8A conceptually shows an approximate rectangular pulse obtained through the third and fourth steps from the time variation of the electromagnetic force represented by the curve 203 (FIG. 7).

  FIG. 8B conceptually shows a time change of opening / closing (on / off) of the switch S1 based on the rectangular pulse shown in FIG. The switch S1 is closed during the period when the rectangular pulse is generated, and the switch S1 is opened during the period when the rectangular pulse is not generated. According to such opening and closing of the switch S1, it is possible to obtain a time change of the electromagnetic force that substantially matches the curve 203 shown in FIG.

  According to the electromagnetic actuator control method described above, the current flowing through the coil L1 can be controlled with high accuracy, and a desired electromagnetic force can be generated. Therefore, the operation of the movable part 1 is stabilized and the efficiency of the electromagnetic actuator 100 is improved.

Embodiment 3 FIG.
In the present embodiment, the switch S1 is controlled based on the position of the movable portion 1 using the same control circuit (FIG. 2) as in the first embodiment. 10 to 13, the vacuum circuit breaker shown in FIG. 1 is schematically drawn, and the change in the position of the movable portion 1 is shown in order. Among the elements constituting the vacuum circuit breaker shown in FIG. 10 to FIG. 13, the same elements as those constituting the vacuum circuit breaker shown in FIG. However, the connecting part 101 is omitted in the broken part. FIG. 14 conceptually shows the activation / inactivation of the detection signals of the sensors 71, 72, and 73 and the time change of opening / closing (on / off) of the switch S1.

  The electromagnetic actuator 100 further includes detected portions 81 and 82 provided on the shaft fixing portion 12 constituting the movable portion 1, sensors 71, 72, and 73, and a control portion 9. The sensor 71 activates a detection signal when the detected portion 81 is close to, for example, opposed to the sensor 71, and gives the detection signal to the control unit 9. Similarly, the sensors 72 and 73 activate the detection signal when the detected portion 82 is close to, for example, opposed to each other, and gives the detection signal to the control unit 9. Control unit 9 includes switch S1 and diode 5 shown in FIG.

  FIG. 9 shows a change with respect to the moving distance of the load force generated in the movable part 1 by a curve 204. The change of the load force with respect to the moving distance is obtained in advance by calculation from the design value of the electromagnetic actuator 100, as in the case of obtaining the time change of the load force shown in FIG.

Based on the load force curve 204, the distances D1, D2, D3, D ^* 2 and further the time points T ^* 0, T ^* 3 are set. At the distance D1, even when the supply of power to the coil L1 is stopped at this time during the movement of the movable part 1 to the end point side as described later, the movable part 1 is not pulled back to the start point side. At the distance D2, the vacuum valve 103 is closed, and the movable part 1 starts to compress the spring 102 via the connection part 101. At the distance D3, the movable part 1 reaches the end point.

For the same reason as in the first embodiment, the magnitude of the electromagnetic force needs to be larger than the magnitude of the load force in order for the movable portion 1 to start moving. Therefore, the electromagnetic force is applied to the coil L1 from the time T ^* 0 that is traced back from the time when the movable part 1 starts to move by the interval τ1 from the start of the generation of the electromagnetic force until the magnitude of the electromagnetic force becomes larger than the magnitude of the load force. It is desirable to start generating.

The electromagnetic force may start to be generated in the coil L1 at the distance D2, but the energy by the electromagnetic force is smaller than the difference between the repulsive energy due to the compression of the spring 102 and the kinetic energy of the movable part 1, and the movable part 1 is the starting point. May be pushed back to the side. Therefore, a distance D ^* 2 that is returned from the distance D2 by a predetermined distance ΔD ^* 2 is set, and the electromagnetic force is started to be generated in the coil L1 when the moving distance of the movable part 1 reaches the distance D ^* 2, as will be described later. It is desirable.

The generation of electromagnetic force by the coil L1 may be terminated when the movable part 1 reaches the end point. However, the movable part 1 is caused by a repulsive force generated when the movable part 1 collides with the end surface of the iron core 4 on the shaft fixing part 12a side. 1 may be pushed back to the starting side. Therefore, it is desirable to end generation of the electromagnetic force by the coil L1 at a time T ^* 3 when the predetermined period τ2 has elapsed from the time when the movable part 1 reaches the end point.

The sensor 71 is provided at a position where the movement of the movable portion 1 can be detected in the vicinity of the shaft fixing portion 12b opposite to the side where the spring 102 is provided. The sensors 72 and 73 are provided in the vicinity of the shaft fixing portion 12a on the side where the spring 102 is provided, at a position where the movement of the movable portion 1 can be detected, and are spaced by a distance ΔD2 (difference between the distance D3 and the distance D ^* 2). is seperated. At this time, the sensor 73 is provided on the spring 102 side with respect to the sensor 72.

When the movable part 1 is at the starting point (FIG. 10), the detected part 81 is provided at a position away from the position where the sensor 71 is opposed to the opposite side of the magnetic body 11 by a distance D1 in the shaft fixing part 12b. It is done. The detected portion 82 is provided at a position away from the position where the sensor 72 faces in the shaft fixing portion 11a by the distance D ^* 2 toward the magnetic body 11 side.

First, by closing the switch S1 at time T ^* 0 (FIG. 14 (d)), current flows through the coil L1 and electromagnetic force starts to be generated. When the predetermined period τ1 elapses, the electromagnetic force exceeds the load force, and the movable part 1 starts to move. When the movable part 1 moves by the distance D1, the detected part 81 faces the sensor 71 (FIG. 11), and the sensor 71 activates the detection signal (FIG. 14 (a)). Upon receiving the detection signal, the control unit 9 opens the switch S1 (FIG. 14 (d)) and interrupts the supply of current to the coil L1. In the horizontal axis shown in FIG. 14D, the movement distance of the movable part 1 is shown when the movement distance of the movable part 1 is from 0 to the distance D3, and the time is shown when the movement distance is before 0 and after the distance D3. ing.

Second, when the movable part 1 moves by the distance D ^* 2, the detected part 82 faces the sensor 72 (FIG. 12), and the sensor 72 activates the detection signal (FIG. 14 (b)). Upon receiving the detection signal, the control unit 9 closes the switch S1 (FIG. 14 (d)) and energizes the coil L1 with the power source V1.

Third, when the movable part 1 further moves by the distance ΔD2 and reaches the end point, the detection part 82 faces the sensor 73 (FIG. 13), and the sensor 73 activates the detection signal (FIG. 14 (c)). . Upon receiving the detection signal, the control unit 9 opens the switch S1 at a time T ^* 3 when the predetermined period τ2 has passed (FIG. 14 (d)). The energization period of the predetermined period τ2 is provided in order to prevent the possibility that the movable part 1 is pushed back to the starting point side by the repulsive force generated when the movable part 1 collides with the end surface of the iron core 4 on the shaft fixing part 12a side. It is desirable that

  A change with respect to the moving distance of the electromagnetic force generated by the coil L1 when the switch S1 is opened and closed according to FIG.

Assuming that the distance D1 is the first predetermined distance, the distance D ^* 2 is the second predetermined distance, and the distance D3 is the third predetermined distance, the above contents can be understood as follows.

That is, after the start of energization of the coil L1 (time T ^* 0), the switch S1 is opened when the movable part 1 moves the first predetermined distance D1. Thereafter, the switch S1 is closed when the movable unit 1 moves the second predetermined distance D ^* 2. More preferably, after that, the switch S1 is opened at a time T ^* 3 when a predetermined period τ2 has elapsed since the movable portion 1 moved the third predetermined distance D3.

Further, the absolute value of the load force f1 generated in the movable part 1 when the movable part 1 is not pulled back to the starting point side even if the switch S1 is opened during the movement of the movable part 1 to the end point side. It is grasped as the first predetermined value. Among the load forces generated in the movable part 1 by the compression of the spring 102, the absolute value of the load force f2 at the initial stage of the compression of the spring 102 is grasped as a second predetermined value. FIG. 9 shows a case where the load forces f1 and f2 are equal. Further, if the interval ΔD ^* 2 is grasped as the fourth predetermined distance, the first to third predetermined distances can be grasped as follows.

That is, the first predetermined distance D1 is a movement distance from the start of the movement of the movable part 1 that becomes the first predetermined value | f1 | in the course of decreasing the absolute value of the load force. The second predetermined distance D ^* 2 becomes a second predetermined value | f2 | in the process of increasing the absolute value of the load force. The fourth predetermined distance D ^* 2 is the fourth distance from the movement distance from the start of the movement of the movable part 1. Is a movement distance retroactive by a predetermined distance ΔD ^* 2. The third predetermined distance D3 is a movement distance from the time when the movable part 1 starts to move when the movable part 1 reaches the end point.

  According to the electromagnetic actuator control method described above, since the current flowing through the coil L1 is controlled based on the position of the movable part 1, the time during which the load force is generated in the movable part 1 and the coil L1 generate the electromagnetic force. Deviation from time can be reduced. Therefore, the operation of the movable part can be controlled with high accuracy.

  In the present embodiment, the method for controlling the electromagnetic actuator described in the second embodiment may be employed. That is, in the method shown in FIG. 6, first, a change with respect to the moving distance of the load force generated in the movable portion 1 is derived instead of the time change of the load force generated in the movable portion 1 (FIG. 9). In the second and third steps, a change with respect to the moving distance of the electromagnetic force generated by the coil L1 and a change with respect to the moving distance of the current flowing through the coil L1 are obtained. Fourth, a rectangular pulse is obtained by converting a change with respect to the moving distance of the current by a pulse width modulation (PWM) method. And based on the change with respect to the moving distance of a rectangular pulse, a some sensor is provided and the opening / closing of a switch is controlled in the control part connected with a some sensor.

  According to this method, it is possible to obtain a desired electromagnetic force, and it is possible to reduce a difference between a time when the load force is generated in the movable part 1 and a time when the coil L1 generates the electromagnetic force.

Embodiment 4 FIG.
In the electromagnetic actuator including the control circuit (FIG. 2) described in the first embodiment, for example, when the switch S1 is switched from the closed state to the open state, a current is generated in the loop circuit formed by the coil L1 and the diode 5. Feedback, and the switching responsiveness of the switch S1 decreases. In this embodiment, switching response is improved.

  FIG. 16 is a diagram conceptually showing the control circuit according to the present embodiment. The control circuit includes a coil L1, an AC power supply V2, a diode 5, and switches S1 and S2. The coil L1 corresponds to the coil L1 shown in FIG.

  The coil L1 and the diode 5 are connected in parallel. The switch S1 is connected in series with the parallel connection of the coil L1 and the diode 5. The switch S2 is connected in parallel with the series connection of the coil L1 and the switch S1. A power source V2 is applied to both ends of the switch S2. For example, semiconductor switches can be employed as the switches S1 and S2. The diode 5 is provided for the same reason as in the first embodiment. Further, if it is understood that the switch S1 is the first switch and the switch S2 is the second switch, the electromagnetic actuator according to the fourth aspect can be obtained.

First, similarly to the first embodiment, the time change of the load force generated in the movable portion 1 is obtained, and the time points T ^* 0, T1, T ^* 2, and T ^* 3 are set (FIG. 3). Then, the switching of the switches S1, S2 is controlled according to the time points T ^* 0, T1, T ^* 2, T ^* 3. FIG. 17 conceptually shows temporal changes in opening / closing (on / off) of the switches S1 and S2.

At time T ^* 0, the switch S1 is closed with the switch S2 open, and the supply of current to the coil L1 is started. Thereafter, at time T1, the switch S2 is also closed with the switch S1 being closed. This makes it difficult for current to flow to the switch S1 side where the impedance of the coil L1 exists, and the supply of current to the coil L1 is almost cut off. At this time, since the switch S1 is in the closed state, it is possible to prevent the current from returning in the loop circuit described above.

At time T ^* 2, the switch S2 is opened with the switch S1 closed. Thereby, supply of the current to the coil L1 is resumed. Thereafter, at time T ^* 3, the switch S1 is opened, and the supply of current to the coil L1 is completed. That is, the operation of the electromagnetic actuator ends.

The time change of the electromagnetic force generated by the coil L1 when the switches S1 and S2 are opened and closed according to FIG. 17 is conceptually shown by a curve 208 in FIG. 18, for example, and the switching responsiveness at the time points T1 and T ^* 3 is shown. Thus, the switching response at the time points T1 and T ^* 3 indicated by the curve 202 shown in FIG.

Time point T1 is the first time point, time point T ^* 2 is the second time point, time period T1 from time point T ^* 0 to time point T1 is the first predetermined time period, time period T1 to time point T ^* 2 is the second time period ΔT ^* 1 The period ΔT2 from the time point T ^* 2 to the time point T ^* 3 is grasped as the third predetermined period (FIG. 17), and the above-described electromagnetic actuator control method can be grasped as follows. That is, the first switch S1 is closed and energization to the coil L1 is started. After the start of energization (time point T ^* 0), the second switch S2 is closed at the first time point T1 when the first predetermined period ΔT1 has elapsed, and the second time period after the second predetermined period ΔT ^* 1 has elapsed from the first time point T1. Open at time T ^* 2. After the elapse of the second time point T ^* 2, the first switch S1 is opened after the third predetermined period ΔT2 has elapsed (T ^* 3).

Further, the load force f1 generated in the movable part 1 when the movable part 1 is not pulled back to the starting point side even if the switch S1 is opened during the movement of the movable part 1 to the end point side (FIG. 3). Is grasped as the first predetermined value. Among the load forces generated in the magnetic body 11 by the compression of the spring 102, the absolute value of the load force f2 (FIG. 3) at the initial stage of the compression of the spring 102 is grasped as a second predetermined value. Furthermore, if the period ΔT ^* 2 (FIG. 18) is grasped as the fourth predetermined period, the first time point T1 and the second time point T ^* 2 can be grasped as follows.

That is, the first time point T1 is a time point when the first predetermined value | f1 | is reached in the process in which the absolute value of the load force decreases. The second time point T ^* 2 is a time point that is back by a fourth predetermined period ΔT ^* 2 from the time point T2 at which the second predetermined value | f2 | is reached in the process of increasing the absolute value of the load force.

  The electromagnetic actuator according to the present embodiment may further include a control unit, and the control unit may perform opening / closing control of the switches S1 and S2 described above.

According to the electromagnetic actuator and the method for controlling the electromagnetic actuator described above, since the current flowing through the coil L1 is interrupted without feedback of the current in the loop circuit, the switching response is improved. In addition, after the start of energization, the current flowing through the coil L1 is cut off when the absolute value of the load force generated in the movable part 1 becomes equal to or lower than the first predetermined value, and the current at the time when the absolute value of the load force becomes equal to or higher than the second predetermined value. A current is passed through the coil L1 from a predetermined period ΔT ^* 2 before 4. Thereby, the difference between the load force and the electromagnetic force is reduced, and the movable portion 1 can be operated at a low speed even when the load force generated in the movable portion 1 is small. Therefore, the operation of the movable part 1 is stabilized.

  Using the electromagnetic actuator according to the present embodiment, the switches S1 and S2 may be controlled by a control method different from that described above. FIG. 19A shows a rectangular pulse obtained by the same method (FIG. 6) as in the second embodiment. FIGS. 19B and 19C conceptually show time changes in opening and closing (on / off) of the switches S1 and S2 based on the rectangular pulse shown in FIG.

At time T ^* 0, the first switch S1 and the second switch are closed. Thereafter, the switch S2 is opened during the period in which the rectangular pulse is generated, and the switch S2 is closed in the period in which the rectangular pulse is not generated. Then, at time T ^* 3, the switch S1 is opened, and the operation of the actuator is finished. According to such opening and closing of the switches S1 and S2, it is possible to obtain a time change of the electromagnetic force substantially coincident with the curve 203 shown in FIG.

  According to the electromagnetic actuator control method described above, the current flowing through the coil L1 can be controlled with high accuracy, and a desired electromagnetic force can be generated. Therefore, in addition to improving the switching response, the operation of the movable part 1 is stabilized.

Embodiment 5 FIG.
In the present embodiment, when the control unit 9 described in the third embodiment includes the switches S1 and S2 and the diode 5 illustrated in FIG. 16, the switches S1 and S2 are controlled based on the position of the movable unit 1. To do. This electromagnetic actuator can be understood that the electromagnetic actuator according to the fourth embodiment further includes sensors 71, 72, 73 for detecting positions, detected portions 81, 82, and a control unit 9.

Setting of distances D1, D2, D3, D ^* 2 (FIG. 9) and time points T ^* 0, T ^* 3 based on the load force curve, positions where the sensors 71, 72, 73 and the detected parts 81, 82 are provided, etc. (FIGS. 10 to 13) are the same as those described in the third embodiment. FIG. 20 conceptually shows the activation / inactivation of the detection signals of the sensors 71, 72, 73 and the time change of opening / closing (on / off) of the switches S1, S2.

First, by closing the switch S1 at time T ^* 0 (FIG. 20 (d)), a current flows through the coil L1 and electromagnetic force starts to be generated. The movable part 1 starts to move from when the predetermined period τ1 has elapsed. When the movable part 1 moves by the distance D1, the detected part 81 faces the sensor 71 (FIG. 11), and the sensor 71 activates the detection signal (FIG. 20 (a)). Upon receiving the detection signal, the control unit 9 closes the switch S2 with the switch S1 closed (FIG. 20E), and interrupts the supply of current to the coil L1. At this time, since the switch S1 is in a closed state, it is possible to prevent a current from being fed back in the loop circuit described in the fourth embodiment. On the horizontal axis shown in FIGS. 20D and 20E, the movement distance of the movable part 1 is shown when the movement distance of the movable part 1 is from 0 to the distance D3, and the movement distance is before 0 and after the distance D3. Time is shown.

Second, when the movable part 1 moves by the distance D ^* 2, the detected part 82 faces the sensor 72 (FIG. 12), and the sensor 72 activates the detection signal (FIG. 20 (b)). Upon receiving the detection signal, the control unit 9 opens the switch S2 with the switch S1 closed (FIG. 20 (e)), and the supply of current to the coil L1 is resumed.

Third, when the movable part 1 further moves by the distance ΔD2 and reaches the end point, the detection part 82 faces the sensor 73 (FIG. 13), and the sensor 73 activates the detection signal (FIG. 20 (c)). . Upon receiving the detection signal, the control unit 9 opens the switch S1 at the time T ^* 3 when the predetermined period τ2 has elapsed (FIG. 20 (d)). The energization period of the predetermined period τ2 is provided in order to prevent the possibility that the movable part 1 is pushed back to the starting point side by the repulsive force generated when the movable part 1 collides with the end surface of the iron core 4 on the shaft fixing part 12a side. It is desirable that

  A change with respect to the moving distance of the electromagnetic force generated by the coil L1 when the switches S1 and S2 are opened and closed according to FIGS. 20D and 20E is conceptually shown by a curve 209 in FIG. 21, for example, at the distance D1. The switching responsiveness is improved over the switching responsiveness at the distance D1 indicated by the curve 205 shown in FIG.

If the switches S1 and S2 are the first and second switches, the distance D1 is the first predetermined distance, the distance D ^* 2 is the second predetermined distance, and the distance D3 is the third predetermined distance, Can be grasped like this.

That is, the first switch S1 is closed and energization of the coil L1 is started. After the energization of the coil L1 is started, the second switch S2 is closed when the movable part 1 moves the first predetermined distance D1. Thereafter, the second switch S2 is opened when the movable portion 1 moves the second predetermined distance D ^* 2. More preferably, after that, the first switch S1 is opened when a predetermined period τ2 elapses after the movable portion 1 moves the third predetermined distance D3.

Further, the load force f1 generated in the movable part 1 when the movable part 1 is not pulled back to the starting point side even if the switch S1 is opened during the movement of the movable part 1 to the end point side (FIG. 9). Is grasped as the first predetermined value. Among the load forces generated in the magnetic body 11 by the compression of the spring 102, the absolute value of the load force f2 (FIG. 9) at the initial stage of the compression of the spring 102 is grasped as a second predetermined value. Furthermore, if the interval ΔD ^* 2 (FIG. 9) is grasped as the fourth predetermined distance, the first to third predetermined periods can be grasped as follows.

That is, the first predetermined distance D1 is a movement distance from the start of the movement of the movable part 1 that becomes the first predetermined value | f1 | in the course of decreasing the absolute value of the load force. The second predetermined distance D ^* 2 becomes a second predetermined value | f2 | in the process of increasing the absolute value of the load force. The fourth predetermined distance D ^* 2 is the fourth distance from the movement distance from the start of the movement of the movable part 1. Is a movement distance retroactive by a predetermined distance ΔD ^* 2. The third predetermined distance D3 is a movement distance from the time when the movable part 1 starts to move when the movable part 1 reaches the end point.

  According to the electromagnetic actuator control method described above, since the current flowing through the coil L1 is controlled based on the position of the movable part 1, the time during which the load force is generated in the movable part 1 and the electromagnetic force is generated in the coil L1. Deviation from time can be reduced. Therefore, in addition to improving switching responsiveness, the operation of the movable part can be controlled with high accuracy.

  In the present embodiment, a method of generating a rectangular pulse among the electromagnetic actuator control methods described in the fourth embodiment may be employed. That is, in the method shown in FIG. 6, first, a change with respect to the moving distance of the load force generated in the movable portion 1 is derived instead of the time change of the load force generated in the movable portion 1 (FIG. 9). In the second and third steps, a change with respect to the moving distance of the electromagnetic force generated by the coil L1 and a change with respect to the moving distance of the current flowing through the coil L1 are obtained. Fourth, a rectangular pulse is obtained by converting a change with respect to the moving distance of the current by a pulse width modulation (PWM) method. And based on the change with respect to the movement distance of a rectangular pulse, a some sensor is provided and the opening / closing of switch S1, S2 is controlled in the control part connected with a some sensor.

  According to this method, it is possible to obtain a desired electromagnetic force, and it is possible to reduce a difference between a time when the load force is generated in the movable part 1 and a time when the coil L1 generates the electromagnetic force.

Embodiment 6 FIG.
FIG. 22 is a diagram conceptually showing a control circuit included in the electromagnetic actuator 100 according to the present embodiment. The control circuit includes a coil L1, a diode 5, capacitors C1 and C2, and thyristors 61 and 62. The coil L1 corresponds to the coil L1 shown in FIG.

  The coil L1 and the diode 5 are connected in parallel. A capacitor C1 is connected to both ends of the parallel connection of the coil L1 and the diode 5 via a thyristor 61, and a capacitor C2 is connected via a thyristor 62. The diode 5 is connected for the same reason as in the first embodiment.

  If the capacitor C1 is a first capacitor, the capacitor C2 is a second capacitor, the thyristor 61 is a first thyristor, and the thyristor 62 is a second thyristor, the above contents can be grasped as follows. That is, the electromagnetic actuator 100 includes the coil L1, the power source 21 that supplies current to the coil L1, and the movable unit 1 that operates by the electromagnetic force generated by the coil L1. The power source 21 is connected in parallel to the first capacitor C1 and the first thyristor 61 connected in series with each other, the series connection of the first capacitor C1 and the first thyristor 61, and the second connected in series with each other. A capacitor C2 and a thyristor 62;

  FIG. 23 shows the relationship between the discharge time of capacitors C1 and C2 and the amount of current. Since the charge amount of the capacitor depends on the capacitance of the capacitor, the curve 211 changes from the curve 211 indicating the relationship between the discharge time and the current amount to the curve 213 as the capacitance of the capacitor increases. A curve 214 shows a change with time in the amount of current of a power source that can supply a constant current for comparison with a capacitor.

  For the capacitor C1, the relationship between the discharge time and the current amount is, for example, a curve 211, and for the capacitor C2, the relationship between the discharge time and the current amount is, for example, a curve 212. The discharge time intervals Δt1 and Δt2 are intervals from the start of the discharge by the capacitors C1 and C2 to the time when the amount of current becomes small enough to recognize that the discharge has ended.

Similar to the first embodiment, the time change of the load force generated in the movable portion 1 is obtained, and time points T ^* 0, T1, T ^* 2, and T ^* 3 are set (FIG. 3), and there is no electromagnetic force. Also, the time point T4 is set so that the load force is small enough that the movable part 1 is not pulled back to the starting point side (FIG. 25).

FIG. 24 conceptually shows the timing when the thyristors 61 and 62 are turned on. At time T ^* 0, the thyristor 61 is turned on (FIG. 24 (a)), and the capacitor C1 is discharged to start supplying current to the coil L1. It is desirable that the interval Δt1 of the discharge time of the capacitor C1 is substantially the same as the period ΔT4 (interval from time T ^* 0 to time T4). This is because the thyristor 61 is automatically turned off when the amount of current flowing through the thyristor 61 becomes small, so that the current flowing through the coil L1 is cut off at time T4 when the period ΔT4 has elapsed from time T ^* 0.

At time T ^* 2, the thyristor 62 is turned on (FIG. 24B), and the capacitor C2 is discharged to start supplying current to the coil L1. By making the discharge time interval Δt2 of the capacitor C1 substantially equal to the period ΔT2, the supply of current to the coil L1 is cut off at the time T ^* 3 (the thyristor 62 is automatically turned off), and the operation of the electromagnetic actuator Ends.

  The change with time of the electromagnetic force generated in the coil L1 when the thyristors 61 and 62 are turned on according to FIGS. 24A and 24B is a curve 206 shown in FIG. 25, for example.

  According to the electromagnetic actuator described above, after the first thyristor 61 and the second thyristor 62 are turned on, the first capacitor C1 and the second capacitor C2 are discharged. Thereafter, the current flowing from the capacitor C1 and the capacitor C2 decreases, and the first thyristor 61 and the second thyristor 62 are automatically turned off. Therefore, by setting the intervals Δt1 and Δt2 between the discharge times of the first capacitor C1 and the second capacitor C2 to be substantially equal to the predetermined periods ΔT4 and ΔT2, only the timing of turning on the first thyristor and the second thyristor is controlled The current flowing through the coil L1 can be controlled. Further, the operation of the movable portion 1 is stabilized, and the efficiency of the electromagnetic actuator 100 is improved.

  In the present embodiment, when the thyristors 61 and 62 are open, the electromagnetic actuator can be operated repeatedly by charging the capacitors C1 and C2.

Embodiment 7 FIG.
FIG. 26 conceptually shows a control circuit included in the electromagnetic actuator 100 according to the present embodiment. The control circuit includes a coil L1, a diode 5, a capacitor C3, a thyristor 63, switches S1 and S3, and a charging power source V3. The coil L1 corresponds to the coil L1 shown in FIG.

  The coil L1 and the diode 5 are connected in parallel. A switch S1 is connected in series with the parallel connection of the coil L1 and the diode 5. A series connection of the capacitor C3 and the thyristor 63 is connected to both ends of the parallel connection of the coil L1 and the diode 5 via the switch S1. The series connection of the capacitor C3 and the thyristor 63 can be grasped as the power source 22. The charging power source V3 applies a voltage across the capacitor C3 via the switch S3. The diode 5 is connected for the same reason as in the first embodiment. For example, semiconductor switches can be used as the switches S1 and S3.

  For the capacitor C3, the relationship between the discharge time and the current amount is, for example, a curve 213 (FIG. 23), and for the charging power supply V3, the change of the current amount with respect to time is represented by, for example, the curve 214. The discharge time interval Δt3 is an interval from the start of the discharge by the capacitor C3 to the time when the amount of current becomes small enough to recognize that the discharge has ended. Of the interval Δt3, when the period Δt (FIG. 23) in which the value of the current discharged by the capacitor C3 is larger than the value of the current of the charging power supply V3 is longer, a large current can flow through the coil L1 for a longer time. This is desirable.

Similar to the first embodiment, the time change of the load force generated in the movable part 1 is obtained, and the time points T ^* 0, T1, T ^* 2, and T ^* 3 are set (FIG. 3), the opening / closing of the switch S1 and the thyristor. The timing of turning on 63 is controlled. FIG. 27 conceptually shows (a) time variation of opening / closing (on / off) of the switch S1 and (b) timing of turning on the thyristor 63.

At time T ^* 0, by turning on the switch S1 and the thyristor 63 (FIGS. 27A and 27B), the capacitor C3 is discharged, and supply of current to the coil L1 is started. At this time, the switch S3 is opened, and the capacitor C3 is not charged by the charging power source V3. Thereafter, the current supply to the coil L1 is cut off by opening the switch S1 at the time T1. Along with this, the thyristor 63 is automatically turned off, and then the switch S3 is closed and the capacitor C3 is charged by the charging power source V3.

At time T ^* 2, by turning on the switch S1 and the thyristor 63 (FIGS. 27A and 27B), the capacitor C3 is discharged and the supply of current to the coil L1 is resumed. At this time, the switch S3 is opened, and the capacitor C3 is not charged by the charging power source V3. Thereafter, the current supply to the coil L1 is interrupted by opening the switch S1 at time T ^* 3, and the operation of the electromagnetic actuator 100 is completed. For example, the switch S3 may be closed after the operation is completed, and the capacitor C3 may be charged by the charging power source V3.

  The change with time of the electromagnetic force generated in the coil L1 when the switch S1 and the thyristor 63 are controlled according to FIGS. 27A and 27B is a curve 207 shown in FIG. 28, for example.

  According to the electromagnetic actuator 100 according to the present embodiment, it is possible to cause the coil L1 to generate a large electromagnetic force by flowing a current larger than the current obtained from the charging power supply V3 to the coil L1. Further, the operation of the movable portion 1 is stabilized, and the efficiency of the electromagnetic actuator 100 is improved.

It is sectional drawing which shows notionally the vacuum circuit breaker which can apply this invention. 2 is a circuit diagram conceptually showing a control circuit described in the first embodiment. FIG. It is a figure which shows the time change of the load force which arises in the movable part. It is a figure which shows the time change of opening and closing of switch S1. It is a figure which shows the time change of the electromagnetic force which the coil L1 generate | occur | produces. FIG. 10 is a flowchart illustrating steps for deriving a rectangular pulse described in the second embodiment. It is a figure which shows the time change of the electromagnetic force which the coil L1 generate | occur | produces. It is a figure which shows the time change of (a) a rectangular pulse and (b) opening and closing of switch S1, respectively. It is a figure which shows the change with respect to the moving distance of the load force which arises in the movable part 1 demonstrated in Embodiment 3. FIG. It is a top view which shows roughly the vacuum circuit breaker shown by FIG. It is a top view which shows roughly the vacuum circuit breaker shown by FIG. It is a top view which shows roughly the vacuum circuit breaker shown by FIG. It is a top view which shows roughly the vacuum circuit breaker shown by FIG. (A)-(c) It is a figure which shows activation / deactivation of the detection signal of sensors 71, 72, 73, and (d) time change of opening and closing of switch S1, respectively. It is a figure which shows the change with respect to the moving distance of the electromagnetic force which the coil L1 generate | occur | produces. FIG. 10 is a circuit diagram conceptually showing a control circuit described in a fourth embodiment. It is a figure which shows the time change of opening and closing of switch S1, S2. It is a figure which shows the time change of the electromagnetic force which the coil L1 generate | occur | produces. (A) Rectangular pulse, (b), (c) Changes in time of opening and closing of switches S1, S2 are respectively shown. (A) to (c) The activation / inactivation of the detection signals of the sensors 71, 72, and 73, and (d) and (e) the change with time of opening and closing of the switches S1 and S2, respectively, are described. FIG. It is a figure which shows the change with respect to the moving distance of the electromagnetic force which the coil L1 generate | occur | produces. FIG. 10 is a circuit diagram conceptually showing a control circuit described in a sixth embodiment. It is a figure which shows the relationship between the discharge time of a capacitor | condenser, and electric current amount. It is a figure which shows the timing which turns on thyristor 61,62. It is a figure which shows the time change of the electromagnetic force which the coil L1 generate | occur | produces. FIG. 17 is a circuit diagram conceptually showing a control circuit described in a seventh embodiment. (a) It is a figure which shows the time change of opening and closing of switch S1, and (b) the timing which turns on the thyristor 63, respectively. It is a figure which shows the time change of the electromagnetic force which the coil L1 generate | occur | produces.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Movable part, 9 Control part, 100 Electromagnetic actuator, L1 coil, S1, S2 switch, V1 power supply, T1, T ^* 2 time point, ΔT1, ΔT2, ΔT ^* 1, ΔT ^* 2 period, f1, f2 load force, D1 , D ^* 2, D3 distance, ΔD ^* 2 interval (fourth predetermined distance), 21, 22 power supply, 61-63 thyristor, C1-C3 capacitor.

Claims (10)

In an electromagnetic actuator comprising a coil, a power source for supplying current to the coil, a movable part that is moved by electromagnetic force generated by the coil, and a switch connected in series to the coil,
The switch is opened at a first time point after a first predetermined period has elapsed after starting energization of the coil;
The switch is then closed at a second time point and opened after a second predetermined period of time has elapsed from the second time point,
The time change of the load force generated in the movable part is obtained in advance,
The first time point is a time point when the absolute value of the load force becomes a first predetermined value in the process of decreasing,
The method of controlling an electromagnetic actuator, wherein the second time point is a time point that is traced back by a third predetermined period from a time point when the absolute value of the load force is increased to a second predetermined value. In an electromagnetic actuator comprising a coil, a power source that supplies current to the coil, a movable part that moves from a starting point to an end point by electromagnetic force generated by the coil, and a switch connected in series to the coil,
Obtain in advance the time change of the load force generated in the movable part during the period from the start point to the end point of the movable part,
The time change of the electromagnetic force generated by the coil is determined by incrementing the time change of the load force by a predetermined force,
Obtain the time change of the electromagnetic force, obtain the time change of the current flowing through the coil,
By converting the time change of the current by a pulse width modulation method, a rectangular pulse is obtained,
The electromagnetic actuator control method, wherein the switch opens and closes in accordance with the value of the rectangular pulse. In an electromagnetic actuator comprising a coil, a power source for supplying current to the coil, a movable part that is moved by electromagnetic force generated by the coil, and a switch connected in series to the coil,
Opening the switch when the movable part has moved a first predetermined distance after starting energization of the coil;
Closing the switch when the movable part has moved a second predetermined distance;
Opening the switch when a predetermined period of time has passed since the movable part has moved a third predetermined distance,
The change with respect to the moving distance of the load force generated in the movable part is obtained in advance,
The first predetermined distance is a movement distance from the start of the movement of the movable part, which becomes a first predetermined value in the process of decreasing the absolute value of the load force,
The second predetermined distance becomes a second predetermined value in the process of increasing the absolute value of the load force. The second predetermined distance goes back by a fourth predetermined distance from the moving distance from the start of the movement of the movable part. Travel distance
The third predetermined distance is a method for controlling an electromagnetic actuator, which is a movement distance from the time when the movable part starts to move when the movable part 1 reaches an end point. Coils,
A movable part that operates by electromagnetic force generated by the coil;
A diode connected in parallel to the coil;
A first switch connected in series with a parallel connection of the coil and the diode;
An electromagnetic actuator comprising: a second switch connected in parallel to the series connection of the coil and the first switch, and a voltage is applied to both ends thereof. Close the first switch and start energizing the coil;
The second switch is closed at a first time when a first predetermined period has elapsed after starting energization of the coil, and is opened at a second time when a second predetermined period has elapsed from the first time,
Opening the first switch after a third predetermined period has elapsed after the second time point has elapsed;
A control unit;
The time change of the load force generated in the movable part is obtained in advance,
The first time point is a time point when the absolute value of the load force becomes a first predetermined value in the process of decreasing,
5. The electromagnetic actuator according to claim 4, wherein the second time point is a time point that is back by a fourth predetermined period from a time point when the absolute value of the load force is increased to a second predetermined value. The electromagnetic actuator according to claim 4, wherein
The first switch is closed to start energization of the coil;
The second switch is closed at a first time when a first predetermined period has elapsed after the start of energization of the coil, and is opened at a second time when a second predetermined period has elapsed from the first time; ,
The first switch is opened after a third predetermined period has elapsed after the second time point has elapsed,
The time change of the load force generated in the movable part is obtained in advance,
The first time point is a time point when the absolute value of the load force becomes a first predetermined value in the process of decreasing,
The method of controlling an electromagnetic actuator, wherein the second time point is a time point that is back by a fourth predetermined period from a time point when the absolute value of the load force is increased to a second predetermined value. The electromagnetic actuator according to claim 4, wherein
The movable part moves from the start point to the end point,
Obtain in advance the time change of the load force generated in the movable part during the period from the start point to the end point of the movable part,
The time change of the electromagnetic force generated by the coil is determined by incrementing the time change of the load force by a predetermined force,
Obtain the time change of the electromagnetic force, obtain the time change of the current flowing through the coil,
By converting the time change of the current by a pulse width modulation method, a rectangular pulse is obtained,
The first switch is closed to start energization of the coil;
The second switch opens and closes corresponding to the value of the rectangular pulse;
And a step of opening the first switch after a predetermined period has elapsed after starting energization of the coil. The electromagnetic actuator according to claim 4, wherein
The first switch is closed to start energization of the coil;
Closing the second switch when the movable part moves a first predetermined distance after energization of the coil is started;
Opening the second switch when the movable part has moved a second predetermined distance;
Opening the first switch when a predetermined period has elapsed since the movable part has moved a third predetermined distance,
The change with respect to the moving distance of the load force generated in the movable part is obtained in advance,
The first predetermined distance is a movement distance from the start of the movement of the movable part, which becomes a first predetermined value in the process of decreasing the absolute value of the load force,
The second predetermined distance becomes a second predetermined value in the process of increasing the absolute value of the load force. The second predetermined distance goes back by a fourth predetermined distance from the moving distance from the start of the movement of the movable part. Travel distance
The third predetermined distance is a method for controlling an electromagnetic actuator, which is a movement distance from the time when the movable part starts to move when the movable part 1 reaches an end point. Coils,
A power supply for supplying current to the coil;
A movable part that operates by electromagnetic force generated by the coil,
The power supply is
A first capacitor and a first thyristor connected in series with each other;
An electromagnetic actuator comprising a second capacitor and a second thyristor connected in parallel to each other in series with the first capacitor and the first thyristor and connected in series with each other. Coils,
A power supply for supplying current to the coil;
A movable part that operates by electromagnetic force generated by the coil;
A switch connected in series to the coil,
The power source is an electromagnetic actuator having a capacitor and a thyristor connected in series with each other.

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