WO2002091551A1

WO2002091551A1 - Magnetically driving apparatus

Info

Publication number: WO2002091551A1
Application number: PCT/JP2002/004490
Authority: WO
Inventors: Misao Nojiri
Original assignee: Staf Corporation
Priority date: 2001-05-08
Filing date: 2002-05-08
Publication date: 2002-11-14
Also published as: JP2003174759A

Abstract

The miniaturization of a magnetically driving apparatus for driving a permanent magnet with the magnetic field of a solenoid coil and the generation of a strong drive power. Two air-core coils (22, 23) are arrayed linearly with their axes kept coincident so as to generate magnetic fields in opposite directions. A perforated flux converging core (21) of a ferromagnetic material is sandwiched between the air-core coils (22, 23).

Description

Specification

Technical field

The present invention relates to a magnetic drive device, and more particularly to a small and powerful magnetic drive device that drives a permanent magnet with a magnetic field of a coil. Background art

Conventionally, a magnetic drive device that drives a fluid valve or a diaphragm by driving a ferromagnetic plunger by a magnetic field of a solenoid coil has been used. FIG. 12 is a longitudinal sectional view of a conventional magnetic drive device having one coil. As shown in FIG. 12, the coil 11 of the magnetic drive device is wound around a coil bobbin 12 to be air-core. An armature 13 is provided at the center of the coil bobbin 12. The yoke 14 is a strong material made of iron or the like that entirely surrounds the coil 11, the coil bobbin 12, and the armature 13 except for a part on the outside. The yoke lid 15 is attached to one end of the yoke 14 (left side in FIG. 12) so as to be openable and closable with respect to the yoke 14. At the center of the yoke lid 15, a drive shaft 16 projects outside. The other end of the yoke 14 (right side in FIG. 12) is closed by an armature receiving portion 18 made of a non-magnetic material, and has no protrusion. The drive shaft 16 is joined to the armature 13 on the inside. A spring 17 is provided between the joint and the yoke cover 15.

When a current flows through the coil 11 due to energization from a power supply (not shown) and a magnetic field is generated, the armature 13 is driven to the left from the position shown. That is, a magnetic field is generated in the coil 11, the armature 13 existing inside the coil 11 is drawn into the coil 11 by the magnetic flux, and the drive shaft 16 moves to the left and projects to the left. The armature 13 presses the spring 17 and stops at a position where the forces are balanced. When the current is cut off and the magnetic field in the coil disappears, the armature 13 is pushed back to the right by the elasticity of the spring 17, and stops at the position shown in FIG. Stop. In this way, the drive shaft 16 is driven in such a manner as to vibrate in both the left and right directions in FIG.

As an example of a conventional magnetic drive device having three coils, a device disclosed in JP-A-6-315255 is known. The “movable magnet factor actuator” shown in Fig. 13 (a) uses a magnet movable body in which at least two permanent magnets are arranged with the same polarity facing each other, and effectively uses the magnetic flux generated by each magnetic pole of the permanent magnet. By using it, the thrust and efficiency are improved. At least two permanent magnets facing the same pole are provided with an intermediate magnetic body, and end magnets are provided on the outer end faces of the permanent magnets located at both ends to form a movable magnet. A movable magnet is provided inside the at least three coils. At least three coils are connected so that current flows in different directions with the boundary between the magnetic poles of each permanent magnet.

As an example of a conventional magnetic drive device having two coils, a device disclosed in JP-A-11-204329 is known. The “linear solenoid actuator” shown in Fig. 13 (b) reduces the reluctance of the magnetic circuit, increases the effective magnetic flux, reduces the operating resistance, and centers the mover to increase responsiveness. It is. A radial protrusion protruding from the cylindrical part of the stator toward the inner diameter side supports the four hourglass rollers so that they can roll. The roller acts as a rolling bearing that reduces the moving resistance of the mover in the vertical direction. The magnetic material roller reduces the relatance between the inner diameter of the radial projection and the outer diameter of the mover, that is, the outer diameter of the permanent magnet or the movable core.

However, such a conventional magnetic drive device has a problem that a small device having a strong driving force cannot be realized. In magnetic drive devices, the upper limit of the generated magnetic force is determined by the number of turns of the coil and the current value. Therefore, the force acting on the drive shaft is only up to its upper limit. When a stronger driving force is required, the conventional type of magnetic drive requires a yoke as large as possible and a coil with a large number of turns therein. At that time, continuous heating could not be performed for a long time due to the heat generated by the coil due to the current.

SUMMARY OF THE INVENTION The present invention has been conceived to solve the above-mentioned conventional problems and to provide a magnetic drive device capable of obtaining a strong driving force even in a small size. Disclosure of the invention

In order to solve the above-mentioned problems, in the present invention, a magnetic driving device is provided with a perforated magnetic flux converging core formed of a ferromagnetic material, and a magnetic flux converging core having substantially the same inner diameter as the hole of the magnetic flux concentrating core and having opposite directions. Two air-core coils arranged in a straight line with their axes aligned so as to generate a magnetic field with a magnetic flux focusing core interposed therebetween, and a drive unit for a permanent magnet that passes through the air-core coils A configuration was provided. With this configuration, the driving forces from the two air-core coils can be added, and the device for obtaining the same driving force can be made smaller than a conventional device.

Since the number of turns of the two air-core coils is equal, the forces generated by the magnetic field are balanced, and a compact and powerful drive device can be obtained.

Since the outer diameter of the magnetic flux focusing core is larger than the outer diameter of the air-core coil, it is possible to efficiently cool the air.

Since the configuration is such that a pulse current having a variable repetition frequency is supplied to the air-core coil for driving, it can be driven at a desired cycle.

Since the housing is made of a ferromagnetic material surrounding the magnetic flux focusing core and the air-core coil in contact with the magnetic flux focusing core at a position opposite to the drive unit side, the housing is configured as follows. Since it has a heat radiation effect and a sound insulation effect, the operation of the magnetic drive device is calm, and long-term continuous operation is possible. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a longitudinal sectional view showing a basic configuration of a magnetic drive device according to a first embodiment of the present invention,

FIG. 2 is a longitudinal sectional view for explaining the operation of the magnetic drive device according to the first embodiment of the present invention,

FIG. 3 is a coil drive circuit diagram of the magnetic drive device according to the first embodiment of the present invention,

FIG. 4 is a longitudinal sectional view showing a basic configuration of an air pump using a magnetic drive device according to a second embodiment of the present invention,

FIG. 5 shows a coil drive circuit of a magnetic drive device according to a second embodiment of the present invention. Figure,

FIG. 6 is a longitudinal sectional view showing a configuration of a magnetic drive device according to a third embodiment of the present invention,

FIG. 7 is a longitudinal sectional view showing a configuration of a magnetic drive device according to a fourth embodiment of the present invention,

FIG. 8 is a longitudinal sectional view showing another configuration of the magnetic drive device according to the fourth embodiment of the present invention,

FIG. 9 is a longitudinal sectional view showing a configuration of a magnetic drive device according to a fifth embodiment of the present invention,

FIG. 10 is a longitudinal sectional view showing a configuration of a magnetic drive device according to a sixth embodiment of the present invention,

FIG. 11 is an operation transition diagram showing the operation of the magnetic drive device according to the sixth embodiment of the present invention,

FIG. 12 is a longitudinal sectional view showing the configuration of a conventional magnetic drive device,

FIG. 13 is a longitudinal sectional view showing the configuration of a conventional magnetic drive device having a plurality of coils. BEST MODE FOR CARRYING OUT THE INVENTION

(First Embodiment)

According to the first embodiment of the present invention, two air-core coils are arranged in a straight line with the axes of the air-core coils coincident with each other so as to generate magnetic fields in opposite directions, and the air-core coils and the air-core coils are arranged between the air-core coils. This is a magnetic drive device in which a perforated magnetic flux focusing core made of a ferromagnetic material having the same inner diameter is sandwiched, and a permanent magnet is passed through an air-core coil as a drive unit.

FIG. 1 is a longitudinal sectional view showing a basic configuration of a magnetic drive device according to a first embodiment of the present invention. In FIG. 1, a magnetic flux converging core 21 is a flat ring-shaped ferromagnetic core for converging magnetic flux between two coils. The coils 22 and 23 are air-core coils wound in opposite directions. Coil bobbins 24 and 25 are bobbins for winding coils. The drive unit 26 is a permanent magnet that converts a change in a magnetic field into a mechanical force. The power supply terminal 27 is a terminal for supplying a current to the coil.

FIG. 2 is a vertical view for explaining the operation of the magnetic drive device according to the first embodiment of the present invention. It is sectional drawing. FIG. 2 (a) is a diagram showing a stationary state in which no current flows through the coils 22 and 23. FIG. FIG. 2 (b) is a diagram illustrating the instantaneous state when a magnetic field starts to be generated when the coil is energized. Fig. 2 (c) is a diagram when the magnetic field is in a steady state.

FIG. 3 is a drive circuit diagram of a coil portion of the magnetic drive device according to the first embodiment of the present invention. In FIG. 3, transistors 31 to 34 are switching elements for turning on and off a current from a power supply. The power supply 35 is a power supply that supplies a current to the coil. Ground 36 is the current return path for the power supply.

The operation of the thus configured magnetic drive device according to the first embodiment of the present invention will be described. First, the outline of the function of the magnetic drive device will be described with reference to FIG. Coins 22 and 23 are provided so as to sandwich a ring-shaped magnetic flux focusing core 21 formed of a ferromagnetic material and having a hole. Both coils 22 and 23 are air cores, and the inner diameter is substantially the same as the inner diameter of magnetic flux focusing core 21. The winding directions of the coils 22 and 23 are opposite to each other. Therefore, the magnetic fields generated by both coils are in directions opposite to each other.

The winding start terminal of the coil 22 and the winding start terminal of the coil 23 are commonly connected, and the winding end terminal of the coil 22 and the winding end terminal of the coil 23 are commonly connected. Connect the commonly connected terminals to the power supply terminal 27. A drive unit 26 made of a permanent magnet is passed through the air core portions of the coils 22 and 23. A driving force take-out mechanism (not shown) is provided at an end of the driving section 26. Coil bobbins 24 and 25 are used to fix coils 22 and 23.

The operation of the magnetic drive device will be described with reference to FIG. When no current is flowing through the coil and the drive unit 26 is on the left side of FIG. 2 (a), the magnetic flux focusing core 21 is driven by the permanent magnet of the drive unit 26 as shown in FIG. 2 (a). As shown, the inside is N pole and the outside is S pole. Therefore, the positional relationship between the driving unit 26 and the magnetic flux focusing core 21 is shifted from the magnetic flux focusing core 21 so that the driving unit 26 projects outward from the coil 22.

As shown in FIG. 2 (b), when a current is applied to the coils 22 and 23 to generate a magnetic field, the magnetic flux concentrating core 21 is deviated from the initial magnetization direction by the magnetic fields of the coils 22 and 23. It is magnetized in the opposite direction. That is, since the magnetization of the coils 22 and 23 by the magnetic field is larger than the magnetization by the permanent magnet, the polarity of the magnetic flux focusing core 21 is opposite to the polarity shown in FIG. 2 (a). At this time, the polarity of the S pole on the right side of the drive unit 26 matches the polarity of the S pole inside the magnetic flux focusing core 21 and repels strongly, so that the drive unit 26 moves to the right in the figure. Start.

When the drive unit 26 moves to the right side and the N pole on the left side of the drive unit 26 comes to a position facing the S pole inside the magnetic convergence core 21, the two magnetic poles attract each other and stop. 2 The state shown in Fig. (C) is obtained. The state change from Fig. 2 (b) to Fig. 2 (c) occurs in a short time. In addition to the driving force applied to the driving unit 26 by the magnetic field of the coil, the repulsive force applied to the driving unit 26 by the magnetization of the magnetic flux focusing core 21 is also a large driving force. Therefore, an extremely large driving force is given to the driving section 26 of the permanent magnet.

In the state shown in FIG. 2 (c), when the direction of the current is reversed so as to reverse the magnetic field of the coil, the magnetic poles of the magnetic flux focusing core 21 are reversed, and the driving unit 26 is directed leftward. Driving force acts. The drive unit 26 momentarily moves to the position shown in FIG. 2 (b). At this time, the polarity of the magnetic flux focusing core 21 is opposite to the polarity shown in FIG. 2 (b). As described above, the driving unit 26 is driven strongly and quickly in the left-right direction every time the magnetic field of the coil is reversed, and thus can be used as a vibrator. The drive circuit of the coil of the magnetic drive device will be described with reference to FIG. Transistors 31 to 34 are connected between a power supply 35 for generating a magnetic field in the two coils 22 and 23 and the coils 22 and 23. Transistors 31 and 32 are connected in series between power supply 35 and ground 36, and are connected in series between transistors 33 and 34, power supply 35 and ground 36 to form a bridge-connected switch. ing. The drive pulse for turning on the NPN transistors 31 and 33 is a positive pulse of the power supply voltage, and the drive pulse for turning on the PNP transistors 32 and 34 is a negative pulse of the ground voltage . The left operation pulse for operating the drive unit 26 in the left direction is a pair of a positive pulse for turning on the NPN transistor 31 and a negative pulse for turning on the PNP transistor 34. The right operation pulse for operating the driving unit 26 in the right direction includes a positive pulse for turning on the NPN transistor 33 and a negative pulse for turning on the PNP transistor 32. Is a pair with

An alternating current flows through the coils 22 and 23 by alternately applying the left operation pulse and the right operation pulse at intervals corresponding to the movement cycle of the drive unit 26, respectively. In a magnetic drive device, there are a case where a pulse repetition period is fixed and a case where a repetition period is variable. When the repetition period is constant, the driving speed is constant. If the repetition period is variable, the driving speed can be changed, and more delicate control of the driving force can be performed.

In FIG. 1, the size of the magnetic flux converging core 21 in the diameter direction is larger than the outer diameter of the coil. Magnetic flux focusing core 21 Force S, projecting outward from coil. With this configuration, the coil can be cooled by the magnetic flux concentrating core 21 and can withstand continuous operation for a long time. Further, the outer shape of the magnetic flux focusing core 21 is not limited to a circular shape, but may be formed in a square shape such as a square shape in accordance with a device to be mounted.

Although the number of turns of each coil is configured to be equal in FIG. 1, the number of turns may not be the same due to the design of the device. When driving the driving unit 26, the direction of the current flowing through the coil may be a single direction instead of both directions. Driving only with an applied current from one drive circuit causes uneven driving strength in the left and right directions, but if there is no inconvenience when used in that state, economical operation is possible. In this case, when the permanent magnet moves in the opposite direction to the driving by the magnetic field, the driving force is insufficiently strong as compared with the driving by the magnetic field. For such movement in the opposite direction, an elastic material such as a coil spring can be used.

As described above, in the first embodiment of the present invention, the magnetic drive device is arranged in a straight line with the axes of the two air-core coils aligned so as to generate magnetic fields in opposite directions. Since a core for magnetic flux focusing with a hole made of a ferromagnetic material having substantially the same inside diameter as the air-core coil is sandwiched between the air-core coils and a permanent magnet is passed through the air-core coil to form a drive unit, a compact device is used. However, the permanent magnet can be driven with a large force.

(Second embodiment)

In the second embodiment of the present invention, two air-core coils are aligned in a straight line with their axes aligned to generate magnetic fields in opposite directions, and a ferromagnetic material hole is formed between the air-core coils. Perforated magnetic flux An air pump that drives the permanent magnet in the air-core coil with a single pulse with the focusing core in between This is a magnetic drive device for moving.

FIG. 4 is a cross-sectional view of an air pump using a magnetic drive device according to a second embodiment of the present invention. In FIG. 4, a permanent magnet 41 is a driving member that converts a change in a magnetic field into a mechanical force. The diaphragm 42 is a metal film that changes its shape according to the position of the permanent magnet 41 and sucks or discharges air. The intake valve 43 is a valve that opens when inhaling air. The air suction port 44 is a port for sucking air from outside. The exhaust valve 45 is a valve that opens when exhaling air. The air discharge port 46 is a discharge port that discharges air to the outside. The spring 47 is a buffer for limiting the movement of the permanent magnet 41 to the right. The housing 49 is a non-magnetic protection member that entirely surrounds the magnetic drive device. The other parts are the same as in the first embodiment. FIG. 5 is a coil drive circuit diagram of the magnetic drive device according to the second embodiment of the present invention. In FIG. 5, a transistor 48 is a switching element for turning on and off a current flowing through a coil.

The operation of the magnetic drive device according to the second embodiment of the present invention thus configured will be described. First, an outline of the operation of the magnetic drive device used for the air pump shown in FIG. 4 will be described. In this magnetic drive device, the driving force by the permanent magnet 41 is unidirectional, unlike the first embodiment shown in FIG. When the coils 22 and 23 are not energized, the permanent magnet 41 is stopped at a predetermined position. When a current is applied and a magnetic field is generated in the coil, the permanent magnet 41 moves rightward. When the current is cut off, the permanent magnet 41 is pulled back to the left.

The operation of the air pump using the magnetic drive will be described with reference to FIG. The diaphragm 42 is connected to the permanent magnet 41 and deforms according to the movement of the permanent magnet 41 to change the volume. An air pump is formed by the diaphragm 42, the intake valve 43, and the exhaust valve 45. The air inlet 44 is connected to the intake valve 43, and the air outlet 46 is connected to the exhaust valve 45. The coiled spring 47 is provided between the permanent magnet 41 and the coil bobbin 25 around the shaft.

When the coils 22 and 23 are not energized, the permanent magnet 41 is stopped at the position where the diaphragm 42 is in a stable state. When a current is applied and a magnetic field is generated in the coil, the permanent magnet 41 pulls the diaphragm 42 rightward in FIG. Permanent magnet 41 Is pushed to near the right end, and the movement distance is limited by the spring 47 and stops. During that time, air is sucked in from the air inlet 44 and is taken in from the intake valve 43. When the current is interrupted, the permanent magnet 41 is pulled back to the left by the diaphragm 42. When the permanent magnet 41 returns, the air is discharged from the exhaust valve 45 to the outside via the air discharge port 46. Since the permanent magnet 41 goes too far to the left due to inertia and then returns to the right, air is taken in at that time. By repeating this, the permanent magnet 41 is driven to reciprocate continuously, and the intake and exhaust are performed. An air pump using this magnetic drive device is easy to control because the repetition cycle of intake and exhaust is the same as the pulse application cycle, and has a large driving force, and can be downsized.

With reference to FIG. 5, a drive circuit used to generate a magnetic field in the coils 22 and 23 will be described. N PN type transistor 48 Force is connected between power supply 35 and coils 22 and 23. The drive pulse for turning on the NPN transistor 48 is a positive pulse of the power supply voltage. A single operation pulse is applied every time corresponding to the moving cycle of the permanent magnet 41 to flow current through the coils 22 and 23. When a current flows through the coils 22 and 23, a magnetic field is generated, the magnetic flux focusing core 21 is magnetized, and the permanent magnet 41 is drawn. When the currents of the coils 22 and 23 are cut off, the magnetization of the magnetic flux focusing core 21 weakens, and the permanent magnet 41 returns to a predetermined position.

In this example, the magnetic field of the coils 22 and 23 is generated by a unidirectional drive pulse, but this pulse may be a bipolar pulse. In this case, after the permanent magnet 41 draws the diaphragm 42 rightward, the coils 22 and 23 are excited in the opposite direction, so that the permanent magnet 41 also receives a magnetic field force in addition to the restoring force of the diaphragm 42. 41 can be quickly returned to its original position.

As described above, in the second embodiment of the present invention, the magnetic drive device is arranged in a straight line with the axes of the two air-core coils coincident to generate magnetic fields in opposite directions, A small air pump that is easy to control is realized because the air pump is driven by a single pulse driving the permanent magnet in the air core coil with a ferromagnetic perforated magnetic flux focusing core sandwiched between them. it can.

(Third embodiment)

In the third embodiment of the present invention, the end of the drive section of the permanent magnet Is a magnetic drive device having a short length and a ferromagnetic material added.

FIG. 6 is a longitudinal sectional view showing a configuration of a magnetic drive device according to a third embodiment of the present invention. In FIG. 6, the magnetic materials 28 and 29 are magnetic materials adhered to both ends of the permanent magnet of the driving unit 26. The holding cylinder 30 is a cylinder for integrating the permanent magnet drive unit 26 and the magnetic materials 28 and 29 into a drive unit.

The operation of the thus configured magnetic drive device according to the third embodiment of the present invention will be described. The lengths of the magnetic members 28 and 29 adhered to both ends of the permanent magnet of the drive unit 26 in the major axis direction are shorter than the permanent magnets of the drive unit 26. When the driving unit 26 is driven by the two coils 22 and 23, the magnetic members 28 and 29 move simultaneously with the driving unit 26. Instead of increasing the mass of the drive unit 26 itself, magnetic materials 28 and 29 are added. Since the driving force is proportional to the product of the mass of the driving unit 26 and the moving speed of the driving unit 26, the mass of the driving unit 26 is substantially increased, and the driving force is increased.

As described above, in the third embodiment of the present invention, a ferromagnetic material having an axial length shorter than that of the permanent magnet is added to the end of the drive unit of the permanent magnet of the magnetic drive device. Even in this case, the same driving force as that of a long permanent magnet can be obtained.

(Fourth embodiment)

The fourth embodiment of the present invention is a magnetic drive device that surrounds the magnetic flux focusing core and the air core coil with a housing made of a ferromagnetic material that contacts the outer periphery of the magnetic flux focusing core.

FIG. 7 is a longitudinal sectional view showing a configuration of a magnetic drive device according to a fourth embodiment of the present invention. In FIG. 7, a housing 51 is a member made of a ferromagnetic material that surrounds the magnetic flux focusing core and the air-core coil. The coils 22, 23, the drive unit 26, and the coil bobbins 24, 25 are the same as those in the first embodiment shown in FIG.

FIG. 8 is a longitudinal sectional view showing another configuration of the magnetic drive device according to the fourth embodiment of the present invention. In FIG. 8, a housing 52 is a member made of a ferromagnetic material that surrounds the magnetic flux focusing core and the air-core coil.

The operation of the magnetic drive device according to the fourth embodiment of the present invention thus configured will be described. As shown in FIG. 7, the magnetic flux converging core 21 is in contact with a housing 51 made of a magnetic material at a contact position 50 on the opposite side of the drive unit 26 from the permanent magnet. At the contact position 50, a non-magnetic inclusion exists between the magnetic flux focusing core 21 and the housing 51. not exist. The housing 51 surrounds the outside of the magnetic flux focusing core 21 and the air-core coils 22 and 23. Two metal springs 47 are provided between the drive unit 26 and the coil bobbins 24 and 25 as a cushioning material when the drive unit 26 is driven.

When power is supplied to the two coils 22 and 23 from a power source (not shown), the drive unit 26 repeatedly moves rapidly in the left and right directions in FIG. The magnetic drive device becomes a vibrator (vibrator) by the movement of the drive unit 26. By simply holding the housing 51, it is possible to detect that the device is vibrating. Therefore, it can be used for incoming call detection in the “manner mode” of a mobile phone.

The lines of magnetic force generated by the coils 22 and 23 pass through the inside of the drive unit 26 from the magnetic flux focusing core 21 through the housing 51, and thus the loss of the generated lines of magnetic force is extremely small. Since the housing 51 is a good conductor of heat, the heat dissipation effect on the coils 22 and 23 is large. Since magnetic lines of force do not leak out of the housing 51, no magnetic noise is generated for peripheral devices.

The magnetic drive device shown in FIG. 8 is obtained by partially changing the configuration of the housing 51 shown in FIG. The housing 52 is made of a magnetic material similar to that of the magnetic flux focusing core 21 so that there is no gap therebetween. That is, the magnetic flux focusing core 21 and the housing 52 are integrated. Therefore, the loss of the generated magnetic field lines is further reduced.

As described above, in the fourth embodiment of the present invention, the magnetic drive device is formed of a housing made of a ferromagnetic material that is in contact with the outer periphery of the magnetic flux focusing core, and surrounds the magnetic flux focusing core and the air-core coil. With this configuration, the heat dissipation and sound insulation of the housing makes the operation of the magnetic drive device quiet and allows long-term continuous operation.

(Fifth embodiment)

The fifth embodiment of the present invention is a magnetic drive device in which the magnetic flux converging core has a three-layer structure in which a nonmagnetic material layer is interposed in the axial middle.

FIG. 9 is a longitudinal sectional view showing a configuration of a magnetic drive device according to a fifth embodiment of the present invention. In FIG. 9, the magnetic flux converging cores 61 and 62 are cores having a nonmagnetic material layer 63 interposed therebetween.

The magnetic flux focusing core is divided into a core 61 and a core 62. A three-layer structure is formed with the nonmagnetic material layer 63 interposed therebetween. Lines of magnetic force generated from coils 22 and 23 are used for focusing magnetic flux After passing through the closer one of the cores 61 and 62, it passes through the housing 52. For this reason, the loss of the lines of magnetic force is extremely small, and the magnetic flux focusing core is reduced in size, so that the device can be reduced in weight.

As described above, in the fifth embodiment of the present invention, the magnetic flux focusing core of the magnetic drive device has a three-layer structure in which the non-magnetic material layer is interposed in the middle in the axial direction. Can be quantity.

(Sixth embodiment)

The sixth embodiment of the present invention is a magnetic drive device in which magnetic flux focusing cores are provided on both sides of a set of two coils.

FIG. 10 is a longitudinal sectional view showing a configuration of a magnetic drive device according to a sixth embodiment of the present invention. FIG. 10 (a) is a longitudinal sectional view showing a configuration of a magnetic drive device provided with a plate-ring-shaped ferromagnetic flux focusing core for converging magnetic fluxes at both ends of a set of two coils. is there. FIG. 10 (b) is a longitudinal sectional view showing a configuration of a magnetic drive device provided with a disk-shaped ferromagnetic flux focusing core for converging magnetic fluxes at both ends of a set of two coils. It is. Fig. 10 (c) is a longitudinal section showing the configuration of a magnetic drive device provided with a flat ring-shaped ferromagnetic flux converging core for converging the magnetic flux between the middle and both ends of a set of two coils. FIG. FIG. 10 (d) is a diagram for explaining the restriction on the length of the drive unit. In FIG. 10, the magnetic flux converging core 21 is a flat ring-shaped or disk-shaped ferromagnetic core for converging the magnetic flux outside the two coils. Other configurations are the same as those of the first embodiment.

FIG. 11 is an operation transition diagram showing the operation of the magnetic drive device according to the sixth embodiment of the present invention. FIG. 11 (a) is a diagram showing a state in which no current is flowing through the coil and the permanent magnet of the drive unit is on the left side of the coil. FIG. 11 (b) is a diagram showing a state where the right drive current has begun to flow through the coil. FIG. 11 (c) is a view showing a state in which the permanent magnet of the drive unit comes to the right side of the coil and stops after a right drive current is supplied to the coil.

The operation of the magnetic drive device according to the sixth embodiment of the present invention thus configured will be described. As shown in FIG. 10 (a), two air-core coils 22, 23 are arranged in a straight line with their axes coincident to generate magnetic fields in opposite directions. With ferromagnetic materials The perforated magnetic flux converging core 21 is provided at both ends of a set of two coils 22 and 23. A permanent magnet is passed through the inside of the two coils 22 and 23 to form a drive unit 26. One magnetic flux focusing core is attached to each coil at both ends of the coil set, and the magnetic field generated by each coil is concentrated by the magnetic flux focusing core 21 and the magnetic force is permanently magnetized. Act on the stone drive 26.

In the magnetic drive device having the configuration shown in FIG. 10 (b), a disc-shaped magnetic flux focusing core 21 having no hole is provided at one end of a set of two air-core coils. The distance between the magnetic flux focusing core 21 and the permanent magnet of the drive unit 26 is reduced by making the shape of the magnetic flux focusing core 21 a disk shape instead of a ring shape, thereby reducing the magnetic resistance. . A spring 47 is provided between the drive unit 26 of the permanent magnet and the magnetic flux focusing core 21. Therefore, the drive unit 26 is stably stopped at the center when not operating. In the magnetic drive device having the configuration shown in FIG. 10 (c), the magnetic flux converging core 21 is also provided in the middle of the pair of two air-core coils 22,23. Since the magnetic flux focusing core 21 as a magnetic separation plate is added between the coils, the operation efficiency is improved.

In these configurations, the length of the permanent magnet of the drive unit 26 is limited. As shown in FIG. 10 (d), the upper limit of the length of the permanent magnet of the drive unit 26 is up to the length that does not cover the magnetic flux focusing cores 21 of both sides of the coil set. It does not operate with such a length that the permanent magnet covers the two magnetic flux focusing cores 21.

The operation of the magnetic drive device will be described with reference to FIG. As shown in the operation transition diagram in FIG. 11, the permanent magnets of the drive unit 26 are repelled and attracted by the magnetic flux lines collected in the magnetic flux focusing core 21. When no current is flowing through the coil and the drive unit 26 is on the left side of Fig. 11 (a), the magnetic flux focusing core 21 on the left side is driven by the permanent magnet of the drive unit 26 in Fig. 11 (a). As shown in (a), the inside is the S pole and the outside is the N pole. The magnetic flux focusing core 21 on the right side has an N pole on the inside and an S pole on the outside. The left end of the driving unit 26 is located at a position facing the inside of the magnetic flux converging core 21 and is stably stopped. As shown in Fig. 11 (b), when a current is applied to the coils 22 and 23 to generate a magnetic field, the magnetic flux focusing core 21 on the left side is opposite to the original magnetization direction due to the magnetic field of the coil 22. It is magnetized in the direction. Since the magnetization of the coil 22 due to the magnetic field is larger than that of the permanent magnet, the polarity of the magnetic flux focusing core 21 is reversed, as shown in FIG. 11 (a). It is the opposite of polarity. The right magnetic flux focusing core 21 is strongly magnetized by the magnetic field of the coil 23 in the same direction as the initial magnetization direction. The S pole on the right side of the drive unit 26 is opposite in polarity to the N pole inside the magnetic flux focusing core 21 on the right side and strongly attracts each other, so the drive unit 26 starts moving to the right in the figure. I do.

When the drive unit 26 moves to the right and the S pole on the right side of the drive unit 26 comes to a position facing the N pole inside the magnetic focusing core 21 on the right side, both magnetic poles attract each other and stop. As a result, the state shown in FIG. 11 (c) is obtained. In the state shown in FIG. 11 (c), when the direction of the current is reversed so as to reverse the magnetic field of the coil, the magnetic poles of the magnetic flux focusing core 21 are reversed, and the driving unit 26 is turned leftward. The drive unit 26 moves to the position shown in FIG. 11 (b). At this time, the polarity of the magnetic flux focusing core 21 is opposite to the polarity shown in FIG. 11 (b).

As described above, in the sixth embodiment of the present invention, the magnetic drive device is configured such that the magnetic flux focusing cores are attached to both sides of the two coil sets, so that the permanent magnets can be efficiently driven. Can be. Industrial applicability

As is clear from the above description, in the present invention, the magnetic drive device is provided with a perforated magnetic flux converging core formed of a ferromagnetic material, and a magnetic flux concentrating core having substantially the same inner diameter as the hole of the magnetic flux concentrating core and having opposite directions. Equipped with two air-core coils arranged in a straight line with magnetic flux converging cores sandwiched between them so that their axes are aligned so as to generate a magnetic field, and a drive unit for a permanent magnet passed through the air-core coils With the configuration, the driving forces from the two air-core coils can be added, and an effect that a device for obtaining the same driving force can be made smaller than a conventional device can be obtained. That is, since the magnetic flux focusing core is added to the air-core coil, the lines of magnetic force generated by the coil can be converged and a strong driving force can be given to the permanent magnet serving as the driving unit. Therefore, a strong driving force can be obtained even with a small size.

Claims

Scope of Claim 1. Perforated magnetic flux converging core formed of a ferromagnetic material, and a shaft having the same inner diameter as the hole of the magnetic flux converging core and having their axes aligned so as to generate magnetic fields in opposite directions. A magnetic drive comprising: two air-core coils arranged linearly with a magnetic flux focusing core interposed therebetween; and a permanent magnet drive unit penetrating the air-core coil. Dress

2. The magnetic drive device according to claim 1, wherein the number of turns of the two air-core coils is made equal.

3. The magnetic drive device according to claim 1, wherein an outer diameter of the magnetic flux focusing core is larger than an outer diameter of the air core coil.

4. The magnetic drive device according to claim 1, wherein a pulse current having a constant repetition frequency is applied to the air-core coil to drive the coil.

5. The magnetic drive device according to any one of claims 1 to 3, wherein a pulse current having a variable repetition frequency is supplied to the air-core coil for driving.

6. The magnetic drive according to any one of claims 1 to 5, wherein a ferromagnetic material having an axial length shorter than that of the permanent magnet is added to an end of the drive unit of the permanent magnet.

7. A perforated magnetic flux concentrating core formed of a ferromagnetic material, and a magnetic flux concentrating core having the same inner diameter as the hole of the magnetic flux concentrating core and having the axes aligned so as to generate magnetic fields in opposite directions. , Two air-core coils arranged in a straight line with a space between them, a drive unit for a permanent magnet passed through the air-core coil, and the magnetic flux converging at a location opposite to the drive unit side. A magnetic drive device comprising: a housing made of a ferromagnetic material surrounding the magnetic flux converging core and the air-core coil in contact with a magnetic core.

8. The magnetic drive device according to claim 7, wherein the magnetic flux focusing core and the housing are integrally formed of a ferromagnetic material.

9. The magnetic drive device according to claim 7, wherein the magnetic flux converging core has a three-layer structure in which a nonmagnetic material layer is interposed in the middle in the axial direction.

10. A perforated magnetic flux converging core formed of a ferromagnetic material; Two air-core coils arranged in a straight line with the same axis and the same axis so as to generate magnetic fields in opposite directions to the hole, and a drive unit for a permanent magnet passed through the air-core coil A magnetic drive device comprising: a magnetic flux converging core provided at both ends of a set of two air-core coils.

11. The magnetic drive device according to claim 10, wherein the magnetic flux converging core is also provided at a position sandwiched between the two air-core coils.

12. A disk-shaped magnetic flux converging core formed of a ferromagnetic material, two air-core coils arranged in a straight line with their axes aligned to generate magnetic fields in opposite directions, and the air-core A magnetic drive device, comprising: a permanent magnet drive unit penetrated in a coil; and the magnetic flux converging cores provided at both ends of a set of the two air-core coils.