JPH079081U - Movable magnet type actuator - Google Patents

Abstract

(57) [Abstract] [Purpose] By effectively utilizing the magnetic flux generated by the magnetic poles of a plurality of permanent magnets included in a movable magnet body, thrust and efficiency are improved, and at the same time, each permanent magnet penetrates a through shaft The permanent magnets are fixed to each other so as to be slidably supported, the permanent magnets are securely fixed and the assembling is facilitated, and the movement of the magnet movable body is smoothed. [Structure] Two permanent magnets 5A, 5B having the same poles facing each other and a penetrating shaft body 8 penetrating an intermediate magnetic body 6 arranged between the permanent magnets are attached to the permanent magnets 5A, 5B and the intermediate magnetic body. 6 is fixed to form the magnet movable body 3, and the penetrating shaft body 8 is slidably supported by the bearing member 22 to form the triple coils 2A, 2
The magnet movable body 3 is movably provided inside B and 2C,
The three coils 2A, 2B and 2C are connected to the permanent magnets 5 respectively.
The wires are connected so that current flows in different directions with the magnetic poles A and 5B as a boundary.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a movable magnet type actuator for converting electric energy into reciprocating kinetic energy and the like by electromagnetic operation in control equipment, electronic equipment, machine tools and the like.

[0002]

[Prior art]

 Conventionally, as a movable magnet type reciprocating device, there are a reciprocating device having the structure of the first conventional example shown in FIG. 8 and a structure having the second conventional example shown in FIG.

In the first conventional example of FIG. 8, reference numeral 10 denotes a magnet movable body composed of a rod-shaped permanent magnet magnetized in the axial direction, and has magnetic poles on both end faces. The coils 11A and 11B are wound around the outer peripheral side of the end of the magnet movable body 10 so as to circulate in a ring shape, and the same pole is generated in adjacent portions. Although not shown, the coils 11A and 11B are usually mounted on a guide cylinder body for guiding the movable magnet body 10 movably in the axial direction. The magnetic flux from each end surface of the movable magnet body 10 is linked to the coils 11A and 11B, respectively.

In the second conventional example shown in FIG. 9, the movable magnet body 15 is composed of two rod-shaped permanent magnets 16A and 16B having the same pole facing each other and a rod-shaped soft magnetic body 17 fixed between these permanent magnets 16A and 16B. Are fixedly integrated with each other, and the coil 18 is wound so as to circulate in an annular shape on the outer peripheral side of the intermediate portion of the magnet movable body 15. Although not shown, the coil 18 is usually attached to a guide cylinder body for guiding the movable magnet body 15 movably in the axial direction. The magnetic fluxes from the end faces of the permanent magnets of the movable magnet body 15 facing each other with the same pole are linked with the coil 18.

By the way, in the first conventional example and the second conventional example, the thrust generated in the magnet movable bodies 10 and 15 is basically similar to the thrust given based on Fleming's left-hand rule ( Fleming's left-hand rule is applied to the coil, but since the coil is fixed here, thrust is generated as a reaction force of the force acting on the coil in the movable magnet body.) Therefore, it is the vertical component of the magnetic flux of the permanent magnet of the magnet movable body (the component orthogonal to the axial direction of the permanent magnet) that contributes to the thrust.

Therefore, in the case of one permanent magnet or in the case of two permanent magnets of the same pole facing each other, the respective vertical components of the magnetic flux were analyzed.

FIG. 10 shows the result of magnetic field analysis of the vertical component of the surface magnetic flux density along the longitudinal side surface of a single permanent magnet. However, the permanent magnet was a rare earth permanent magnet, had a diameter of 2.5 mm and a length of 6 mm, and measured the position 0.25 to 0.45 mm away from the surface of the permanent magnet.

FIG. 11 shows the results of magnetic field analysis of the vertical component of the surface magnetic flux density along the longitudinal side surfaces of the two permanent magnets in the case where the two permanent magnets are arranged in the same pole and facing each other and are directly bonded. Show. However, each permanent magnet was a rare earth permanent magnet, had a diameter of 2.5 mm and a length of 3 mm (two magnets were 6 mm), and measured the position 0.25 to 0.45 mm away from the surface of the permanent magnet.

FIG. 12 shows a magnetic field analysis of the vertical component of the surface magnetic flux density along the longitudinal side faces of the two permanent magnets when the two permanent magnets have the same poles facing each other and the facing distance is 1 mm. The result is shown. However, each permanent magnet was a rare earth permanent magnet, had a diameter of 2.5 mm and a length of 3 mm, and measured the position 0.25 to 0.45 mm away from the surface of the permanent magnet.

FIG. 13 shows a magnetic field analysis of the vertical component of the surface magnetic flux density along the longitudinal side surfaces of the two permanent magnets when the two permanent magnets have the same poles facing each other and the facing distance is 2 mm. The result is shown. However, each permanent magnet was a rare earth permanent magnet, had a diameter of 2.5 mm and a length of 3 mm, and measured the position 0.25 to 0.45 mm away from the surface of the permanent magnet.

FIG. 14 shows a magnetic field analysis of the vertical component of the surface magnetic flux density along the longitudinal side faces of the two permanent magnets when the two permanent magnets have the same pole facing each other and the facing distance is 3 mm. The result is shown. However, each permanent magnet was a rare earth permanent magnet, had a diameter of 2.5 mm and a length of 3 mm, and measured the position 0.25 to 0.45 mm away from the surface of the permanent magnet.

FIG. 15 shows a case where two permanent magnets are arranged so as to face each other with the same pole, and a soft magnetic body having a length of 1 mm is arranged between the permanent magnets. The results of magnetic field analysis of the vertical component of the density are shown. However, each permanent magnet was a rare earth permanent magnet, and had a diameter of 2.5 mm and a length of 3 mm, and the position measured 0.25 to 0.45 mm away from the surface of the permanent magnet was measured.

In FIG. 16, two permanent magnets are arranged with the same poles facing each other, a soft magnetic material having a length of 1 mm is arranged between the two permanent magnets, and the permanent magnets are further opposed to the outer circumferences of the two permanent magnets. The results of magnetic field analysis of the vertical component of the surface magnetic flux density along the longitudinal side faces of the two permanent magnets when the yoke is arranged are shown. However, each permanent magnet is a rare earth permanent magnet with a diameter of 2.5 mm and a length of 3 mm, and the yoke has a cylindrical shape surrounding the permanent magnet and has a thickness of 0.5 mm and a length of 10 mm and is separated from the outer circumference of the permanent magnet by 1.25 mm. The vertical component of the surface magnetic flux density was measured at a position 0.25 to 0.45 mm away from the surface of the permanent magnet.

[0014]

[Problems to be solved by the device]

 As described above, the thrust generated in the magnet movable body basically complies with the thrust given based on Fleming's left-hand rule, and the vertical component (permanent component) of the magnetic flux of the permanent magnet that interlinks with the coil. It is desired that there are many components (perpendicular to the axial direction of the magnet), but in the first conventional example of FIG. 8, the vertical component of the surface magnetic flux density is as shown in FIG. 10, and the two permanent components of FIGS. It was found that the vertical component is small compared to the case where the magnets are arranged opposite to each other. Therefore, the structure of the first conventional example shown in FIG. 8 has a limit in improving the thrust. For example, the magnet movable body 10 is composed of a rare earth permanent magnet with a diameter of 2.5 mm and a length of 6 mm, and 40 mA is applied to each coil 11A, 11B so that the same pole is generated in the adjacent portions of the two coils 11A, 11B. The thrust F1 generated when an electric current of (4) was applied was 4.7 (gf).

On the other hand, in the second conventional example of FIG. 9, a magnet movable body 15 in which a soft magnetic material is arranged between two permanent magnets of the same pole facing each other is used, and the vertical component of the magnetic flux density is shown in FIG. As shown, the magnetic flux emitted from the magnetic poles of the permanent magnets 16A and 16B facing each other is the same as in the case of one permanent magnet (see FIG. 10) or only two permanent magnets (see FIGS. 11 to 14). Although there is a large number, there is only one coil surrounding the intermediate portion of the magnet movable body 15, and there is a dislike that the magnetic flux due to the magnetic poles on both end surfaces of the magnet movable body 15 is not effectively used. Therefore, in the case of the second conventional example shown in FIG. 9, it was difficult to improve the thrust. For example, in the second conventional example of FIG. 9, two rare earth permanent magnets having a diameter of 2.5 mm and a length of 3 mm are used as the magnet movable body 15 (the performance of the rare earth permanent magnet is the same as that of the first conventional example), and both of them are used. Using a soft magnetic material with a length of 1 mm placed between them, a current of 40 mA was applied to the coil 18 that was created to have the same power consumption as the first conventional example in FIG. The thrust F2 generated when it was converted to electric power was 5.6 (gf).

When a plurality of permanent magnets and a magnetic body are combined to form a movable magnet body, it is required to surely integrate them. Also, when an actuator is constructed by providing an output extraction pin on a permanent magnet, it is desirable to eliminate unnecessary rattling of the movable magnet body and output extraction pin, and consideration must be given to that point. .

In view of the above points, the present invention improves the thrust force by using a magnetic movable body in which at least two permanent magnets are arranged with the same poles facing each other and by effectively using the magnetic flux generated by the magnetic poles of the permanent magnets. In addition to improving the efficiency and efficiency, each permanent magnet is fixed to the penetrating shaft to support the penetrating shaft in a slidable manner, so that the permanent magnets are securely fixed and the assembling is facilitated. It is an object of the present invention to provide a movable magnet type actuator in which the movement of a movable body is smoothed.

[0018]

[Means for Solving the Problems]

 In order to achieve the above-mentioned object, the movable magnet type actuator of the present invention comprises: a penetrating shaft body that penetrates at least two permanent magnets having the same poles and an intermediate magnetic body arranged between the permanent magnets; The permanent magnet and the intermediate magnetic body are fixed to form a movable magnet body, and the penetrating shaft body is slidably supported by a bearing member so that the movable magnet body can be moved inside at least three coils. The permanent magnets are connected to each other so that current flows in different directions with the magnetic poles of the permanent magnets as boundaries.

Further, end magnetic bodies may be provided on the outer end surfaces of the permanent magnets located at both ends of the magnet movable body.

Further, a magnetic attraction body for attracting the movable magnet body may be arranged at at least one end of the guide cylinder body to which the at least three continuous coils are fixed.

Alternatively, a spring for pushing back the magnet movable body or a returning permanent magnet that generates a repulsive force between the magnet movable body and the magnet movable body may be arranged at an end position of the guide cylinder.

Further, a structure may be adopted in which the permanent magnet and the magnetic body are fixed to the penetrating shaft body by a retaining ring that engages with the penetrating shaft body.

[0023]

[Action]

 The basic operation principle of the movable magnet type actuator of the present invention will be described with reference to the schematic configuration diagram of the reference example of FIG. In FIG. 6, the movable magnet body 3 includes two columnar permanent magnets 5A and 5B having the same pole facing each other and a columnar soft magnetic body (intermediate portion magnetic body) fixed between these permanent magnets 5A and 5B. As shown in FIG. 15, the magnetic flux density has a large vertical component (a component orthogonal to the axial direction of the permanent magnet). The three coils 2A, 2B and 2C are wound so as to circulate around the outer circumference of the magnet movable body 3, and the left end of the permanent magnet 5A constituting the magnet movable body 3 and the opposite ends of the permanent magnets 5A and 5B having the same poles. And the magnetic flux from the right end magnetic pole of the permanent magnet 5B. These coils 2A, 2B, 2C are connected so that currents flow in different directions at the boundaries between the magnetic poles of the permanent magnets 5A, 5B (the boundary between the magnetic poles is not necessarily the magnetic pole middle if it is between the magnetic poles). It doesn't have to be in the position.). Although not shown, the coils 2A, 2B and 2C are usually mounted on a guide cylinder for guiding the movable magnet body 3 movably in the axial direction. The positional relationship between the coils 2A, 2B and 2C and the magnet movable body 3 is set so that the currents flowing through the coils are opposite to each other across the permanent magnet magnetic poles in the movable range of the magnet movable body 3. It is normal to do.

The basic structure of the movable magnet body 3 in the reference example of FIG. 6 is such that, as shown in FIG. 15, two permanent magnets have the same poles facing each other and a soft magnetic body is arranged between the permanent magnets. In FIG. 15, the vertical component of the surface magnetic flux density in the region Q corresponding to the position of the soft magnetic material is superior to that in FIGS. 11 to 14 where the soft magnetic material is not present (the peak of the magnetic flux density of 0.3T or more). Wide and high peak.)

In this way, the magnet movable body 3 in which the two permanent magnets 5A and 5B have the same poles facing each other and the soft magnetic body 6 is provided between the permanent magnets can contribute to the thrust based on Fleming's left-hand rule. The magnetic flux component perpendicular to the longitudinal direction of the movable magnet body 3 can be increased, and the triple coils 2A, 2B, 2C effectively interlink with the magnetic fluxes of all the magnetic poles of the permanent magnet, so that the triple coils 2A, 2B. , 2C are alternately supplied with a current in a direction in which a magnetic field of opposite polarity is generated, so that a large thrust that cannot be reached in the conventional example can be generated. If the current of each coil is reversed, the direction of the thrust of the movable magnet body 3 is also reversed. When an alternating current is applied, it acts as a vibrator that vibrates repeatedly in a fixed cycle.

In the case of the reference example of FIG. 6 which is the basic configuration of the present invention, for example, two rare earth permanent magnets having a diameter of 2.5 mm and a length of 3 mm are used as the magnet movable body 3 (the performance of the rare earth permanent magnet is 1) It is the same as the conventional example), and a soft magnetic material with a length of 1 mm is placed between the two, and it is made to have the same power consumption as the first and second conventional examples of FIGS. 8 and 9. The thrust F3 generated when a current of 40 mA was applied to the three coils 2A, 2B, and 2C and the power consumption was the same was 6.7 (gf). This is about 1.42 times the thrust of the first conventional example with the same power consumption, and about 1.2 times the thrust of the second conventional example, which is a comparison with the first and second conventional examples. It turns out that it is remarkably excellent.

The curve (a) in FIG. 7 shows the relationship between the axial displacement of the magnet movable body 3 and the thrust (gf) in the case of FIG. 6 (without a yoke). However, the dimensions and characteristics of the permanent magnet are as shown in FIG. 15, and when the midpoint of the magnet movable body 3 is located at the midpoint of the central coil 2B, the amount of displacement is zero, and the current of each coil is Was 40 mA.

The curve (B) in FIG. 7 is obtained when a magnetic yoke is added to the configuration of the reference example in FIG. 6 (however, the dimensions and arrangement of the permanent magnet and the yoke and the characteristics of the permanent magnet are as shown in FIG. 16). The relationship between the axial displacement of the magnet movable body 3 and the thrust (gf), and shows the case where the magnet movable body operates in the direction away from the point where the displacement is zero. The curve (c) is a relationship between the axial displacement of the magnet movable body 3 and the thrust (gf) under the same conditions as the curve (b), and operates in the direction of approaching the point of zero displacement. Indicates when. However, the displacement amount was set to zero when the midpoint of the movable magnet body 3 was located at the midpoint of the central coil 2B, and the current of each coil was set to 40 mA. As described above, in the case where the magnetic yoke is provided, the thrust force is different depending on whether the movable magnet body 3 approaches or moves away from the point where the displacement amount is zero, because the magnetic pole of the permanent magnet of the movable magnet body 3 and the yoke are different. This is because the magnetic attraction force that returns the movable magnet body 3 to the displacement zero point is working.

As described above, in the reference example of FIG. 6 which is the basis of the present invention, the movable magnet body is constituted by the combination structure of permanent magnets of the same pole facing each other. ), The vertical magnetic flux density component can be made sufficiently large, and the magnetic flux generated by all the magnetic poles of the permanent magnet can be effectively used. Therefore, between the current flowing through at least three coils surrounding the movable magnet body, The thrust based on Fleming's left-hand rule can be made sufficiently large, and a large thrust can be obtained with a small size and small current.

The movable magnet type actuator of the present invention is premised on the structure of the reference example of FIG. 6, and further, a plurality of permanent magnets and a magnetic body are securely integrated to produce a movable magnet body, and the magnet is manufactured. The movement of the movable body is smoothed. That is, the permanent magnet and the magnetic body are fixed to the penetrating shaft body that penetrates the permanent magnet and the magnetic body disposed between the permanent magnets to form the movable magnet body. It can be securely fixed to the shaft, making assembly easy. Also, by supporting the penetrating shaft slidably, the movable magnet body can move smoothly inside the coils without rattling, and the end of the penetrating shaft body is provided with an output extraction pin. Available as

[0031]

【Example】

 An embodiment of a movable magnet type actuator according to the present invention will be described below with reference to the drawings.

1 and 2 show a first embodiment of the present invention. In these figures, reference numeral 1 denotes a soft magnetic cylindrical yoke, three coils 2A, 2B and 2C are arranged inside the cylindrical yoke 1, and these coils 2A, 2B and 2C are movable magnets. It is fixed to the cylindrical yoke 1 by an insulating member such as an insulating resin which constitutes a guide cylinder 4 for movably guiding the magnet 3. The inner circumference of the guide cylinder 4 is a circumferential surface.

The magnet movable body 3 is composed of two perforated columnar rare earth permanent magnets 5 A and 5 B having the same poles facing each other, a perforated columnar intermediate soft magnetic body 6 disposed between the permanent magnets, and The metal penetrating shaft body 8 is inserted through the perforated disk-shaped cushion plates 7A, 7B arranged at the outer positions of the permanent magnets 5A, 5B, and the stopper (made of metal) is inserted into the engaging groove 9 of the metal penetrating shaft body 8. The E-ring) 20 is fitted and locked, and the permanent magnets 5A and 5B, the intermediate soft magnetic body 6 and the disc-shaped cushion plates 7A and 7B are fixed to the metal penetrating shaft body 8. Here, the penetrating shaft body 8 is a non-magnetic or magnetic metal, and the cushion plates 7A and 7B are elastic materials such as silicone rubber, and are sandwiched between the pair of stoppers 20 in a slightly compressed state. As a result, the cushion plates 7A and 7B can absorb variations in the thickness of the permanent magnets 5A and 5B and the soft magnetic body 6 and prevent rattling. An adhesive may be used together when the permanent magnets 5A, 5B and the soft magnetic body 6 are integrated with the metal penetrating shaft 8.

The triple coils 2A, 2B, 2C are connected so that currents flow in different directions with the magnetic poles of the permanent magnets 5A, 5B as boundaries. That is, the central coil 2B surrounds the ends of the soft magnetic body 6 and the permanent magnets 5A and 5B including the N poles, and the coils 2A and 2C on both sides include the ends of the permanent magnets 5A and 5B including the S poles. It is wound in an annular shape so that it can be surrounded, and the direction of the current flowing through the central coil 2B is opposite to the direction of the current flowing through the coils 2A and 2C on both sides (in each coil in FIG. 1, (See attached N and S).

Further, non-magnetic side plates 21A and 21B are fitted and fixed to both ends of the soft magnetic cylindrical yoke 1 and the non-magnetic guide cylindrical body 4, respectively, and are burned at the central portions of the side plates 21A and 21B. Cylindrical bearing members 22 such as a binding metal and a highly slidable resin are fixedly supported. The inner peripheral surface of each cylindrical bearing member 22 slidably supports a through shaft body 8 which penetrates and is integrated with the permanent magnets 5A and 5B and the soft magnetic body 6, and one of the through shaft bodies 8 is slidably supported. The end of the is projected outside the bearing member and can be used as an output pin. The side plates 21A and 21B each have a convex portion 23 that fits on the inner peripheral surface of the guide cylinder 4, and the tip end surface of the convex portion 23 is a cushion plate when the magnet movable body 3 moves. The movable range of the magnet movable body 3 is regulated by abutting against 7A and 7B. The bearing member 22 may be non-magnetic or magnetic.

In this first embodiment, since the soft magnetic cylindrical yoke 1 is provided on the outer peripheral side of each coil 2A, 2B, 2C, the vertical component of the surface magnetic flux density of the magnet movable body 3 is as shown in FIG. It is further increased as compared with the reference example. Therefore, the magnetic flux component perpendicular to the longitudinal direction of the magnet moving body 3 that can contribute to the thrust force based on Fleming's left-hand rule can be increased, and the triple coils 2A and 2B that wind around the magnet moving body 3 in an annular shape. , 2C, a larger thrust can be generated by passing a current in the direction of alternately generating magnetic fields of opposite polarities. In the polarity of FIG. 1, the movable magnet body 3 is in the direction of moving to the right, and if the current of each coil is reversed, the direction of the thrust of the movable magnet body 3 is also reversed. When an alternating current is applied, it acts as a vibrator that vibrates repeatedly in a fixed cycle.

Further, the metal penetrating shaft body 8 is inserted through the perforated columnar rare earth permanent magnets 5A, 5B, the perforated columnar intermediate soft magnetic material 6 and the perforated disc-shaped cushion plates 7A, 7B to penetrate the metal. The magnet movable body 3 is configured by fitting the stopper 20 into the engagement groove 9 of the shaft body 8 and locking the same, so that the permanent magnets 5A and 5B and the intermediate soft magnetic body 6 can be fixed and integrated reliably. And easy to assemble.

Further, by supporting the penetrating shaft body 8 integrated with the movable magnet body 3 slidably by the bearing member 22, the rattling of the movable magnet body 3 can be eliminated and the inside of the guide cylinder body 4 can be maintained. The outer circumference of the permanent magnets 5A, 5B and the coil 2A can be regulated concentrically with the center of the circumference, and there is no need to cover the outer circumference of the permanent magnets with a holder or the like for integrating the permanent magnets 5A, 5B and the soft magnetic body 6. , 2B, 2C can be set to the minimum required gap, which is effective in improving thrust. Moreover, since the magnet movable body 3 does not contact the inner peripheral surface of the guide cylinder 4, the magnet movable body 3 can be smoothly moved in the axial direction, and the magnet movable body 3 and the guide cylinder 4 can be moved. It is possible to eliminate problems such as wear of the.

In the structure of the first embodiment, if one or both of the side plates 21A and 21B at both ends are made of soft magnetic material, the side plates made of soft magnetic material attract the magnet movable body 3. It can function as a magnetic adsorbent.

For example, when both the side plates 21A and 21B are made of a soft magnetic material, the magnet movable body 3 is attracted and held by one of the side plates when the coils 2A, 2B and 2C are not energized, and is currently attracted. If a thrust is generated in each of the coils 2A, 2B, 2C in the direction in which the magnet movable body 3 separates from the side plate, the magnet movable body 3 moves in the direction of the side plate on the opposite side to stop the adsorption.

If only one of the side plates is made of a soft magnetic material, the magnet movable body 3 is always attracted to and held by the one side plate when the coils 2A, 2B and 2C are not energized. Can be set to.

FIG. 3 shows a second embodiment of the present invention. In this figure, non-magnetic side plates 21C and 21D are fitted and fixed to both ends of the soft-magnetic cylindrical yoke 1 and the non-magnetic guide cylindrical body 4, respectively, and the inner surfaces of the side plates 21C and 21D and the magnet movable body. A compression spring 24 is arranged between the disk-shaped cushion plates 7A and 7B on the third side. The compression spring 24 has a function of pushing the magnet movable body 3 back to the intermediate position. The other structure is the same as that of the first embodiment.

According to the second embodiment, when the coils 2A, 2B, 2C are not energized, the magnet movable body 3 is moved to the intermediate position in the cylindrical yoke 1 by the elastic force of the left and right compression springs 24. The magnet movable body 3 can be driven to one side by supplying a direct current to each coil 2A, 2B, 2C. Further, when an alternating current is applied, the magnet movable body 3 reciprocates and operates as a vibrator, but the magnet movable body 3 is returned to the intermediate position by the elastic force of the compression spring 24 when it is displaced to some extent. It is possible to prevent the movable magnet body 3 from colliding with the side plates 21C and 21D and generating impact noise.

FIG. 4 shows a third embodiment of the present invention. In this figure, the non-magnetic side plates 21A and 21B are fitted and fixed to both ends of the soft-magnetic cylindrical yoke 1 and the non-magnetic guide cylindrical body 4, respectively, and the inside of the convex portion 23 of the side plates 21A and 21B is fixed. Returning annular permanent magnets 25 are fixed to the circumference. Then, the penetrating shaft body 8 of the magnet movable body 3 penetrates through the inner peripheral holes of the return annular permanent magnet 25 and the bearing member 22. The return annular permanent magnet 25 has a magnetic pole that generates a repulsive force between the permanent magnets 5A and 5B of the movable magnet body 3 on the outer surface of the permanent magnets 5A and 5B on the surface facing the movable magnet body 3. . For example, in FIG. 4, the south pole of the return annular permanent magnet 25 faces the south pole of the outer end surfaces of the permanent magnets 5A and 5B. The other structure is the same as that of the first embodiment.

According to the third embodiment, when the coils 2A, 2B, 2C are not energized, the magnet movable body 3 repels the permanent magnets 5A, 5B and the left and right return annular permanent magnets 25. Then, the magnet movable body 3 can be driven to one side by returning to the intermediate position in the cylindrical yoke 1 and supplying a direct current to each coil 2A, 2B, 2C. Further, when an alternating current is applied, the magnet movable body 3 reciprocates and operates as a vibrator, but when the magnet movable body 3 is displaced to some extent, the permanent magnets 5A and 5B and the left and right annular permanent magnets 25 are moved. Since the magnet movable body 3 is returned to the intermediate position by the repulsive force, it is possible to prevent the impact noise from being generated by the movable magnet body 3 colliding with the side plates 21A, 21B and the annular permanent magnet 25.

FIG. 5 shows a fourth embodiment of the present invention. In this figure, the magnet movable body 3A is composed of two perforated columnar rare earth permanent magnets 5A and 5B having the same poles facing each other, a perforated columnar intermediate portion soft magnetic body 6 disposed between the permanent magnets, Perforated disc-shaped end soft magnetic material 26 arranged outside the permanent magnets 5A, 5B and perforated circular disc-shaped cushion plates 7A, 7B arranged outside the end soft magnetic material 26. The shaft body 8 is inserted, a stopper (metal E ring) 20 is fitted and locked in the engagement groove 9 of the metal through shaft body 8, and the permanent magnets 5A, 5B and the intermediate portion are attached to the metal through shaft body 8. The soft magnetic material 6, the end soft magnetic material 26, and the disk-shaped cushion plates 7A and 7B are fixed. Here, the penetrating shaft 8 is made of non-magnetic or magnetic metal, and the cushion plates 7A and 7B are made of elastic material such as silicon rubber, and are sandwiched between the pair of stoppers 20 in a slightly compressed state. As a result, the cushion plates 7A and 7B can absorb the variations in the thickness of the permanent magnets 5A and 5B and the soft magnetic bodies 6 and 26 to prevent rattling. An adhesive may be used together when the permanent magnets 5A and 5B and the soft magnetic bodies 6 and 26 are integrated with the metal penetrating shaft 8. The thickness of the end soft magnetic material 26 is set to about 1/2 to 1 times that of the intermediate soft magnetic material 6. The other structure is the same as that of the first embodiment.

In the fourth embodiment, the end soft magnetic material 26 is arranged on the outer end surfaces of the permanent magnets 5A, 5B of the movable magnet body 3A, and the end soft magnetic material 26 is projected from the magnetic poles on the outer end surfaces of the permanent magnets 5A, 5B. The vertical component of the magnetic flux density (the component orthogonal to the axial direction of the permanent magnet) in the outer portion of the permanent magnets 5A and 5B is easily changed because the magnetic flux easily bends in the vertical direction due to the presence of the end soft magnetic material 26. Increase. That is, the magnetic flux component perpendicular to the longitudinal direction of the magnet movable body 3A that can contribute to the thrust force based on Fleming's left-hand rule can be increased, and the triple coils 2A, 2B, which are wound around the magnet movable body 3A in an annular shape, An even greater thrust can be generated by applying a current to 2C in the direction in which a magnetic field of opposite polarity is generated alternately. For example, a thrust improvement of several% to 10% can be obtained as compared with the case of the first embodiment without the end soft magnetic material.

In the first to third embodiments, the magnet movable body 3 including the two permanent magnets having the same poles facing each other and the soft magnetic body between the permanent magnets has been exemplified. It is also possible to employ a configuration in which a permanent magnet facing each other and a soft magnetic material between both permanent magnets are provided, and the number of coils can be set to 4 or more correspondingly.

In addition, in the fourth embodiment, a magnet including two permanent magnets of the same pole facing each other, an intermediate soft magnetic material between both permanent magnets, and an outer end soft magnetic material of the two permanent magnets. Although the movable body 3A is illustrated as an example, the movable body 3A may be configured to include three or more permanent magnets of the same pole facing each other, a soft magnetic material between both permanent magnets, and end soft magnetic materials on the outer sides of the permanent magnets located at both ends, Correspondingly, the number of coils can be increased to four or more. Further, in addition to the structure of the fourth embodiment, a compression spring 24 or an annular permanent magnet 25 for returning the magnet movable body described in the second and third embodiments to the intermediate position may be provided.

Further, in each of the embodiments, both sides of the penetrating shaft body of the movable magnet bodies 3 and 3A are supported by the bearings, but a structure in which only one side of the penetrating shaft body is supported by the bearings may be adopted. In this case, there is only one bearing member (however, it is desirable to lengthen the bearing member).

Further, in each embodiment, it is possible to employ a structure in which the guide cylinder 4 is omitted and the coils 2A, 2B, 2C are insulated and fixed to the inner peripheral side of the yoke 1.

Although the cylindrical yoke 1 and the guide cylindrical body 4 are used in the above-mentioned embodiment, a square cylindrical yoke and the guide cylindrical body may be employed, and in this case, each coil is a magnet movable body. It may be wound so as to go around the outer circumference.

[0053]

[Effect of device]

 As described above, according to the movable magnet type actuator of the present invention, the movable magnet type body is used in which the intermediate magnetic body is arranged between at least two permanent magnets having the same poles and is integrated with the penetrating shaft body. Since the through shaft is slidably supported by the bearing member, the magnetic flux component perpendicular to the longitudinal direction of the magnet movable body (the magnetizing direction of the permanent magnet) can be sufficiently increased, and the magnet movable body Since at least three coils are wound so as to surround the circumference, and the magnetic flux generated by each magnetic pole of the magnet movable body can be effectively linked, the magnetic flux between the vertical magnetic flux component and the current flowing through each coil can be effectively linked. The thrust given based on Fleming's left-hand rule can be made sufficiently large. Further, by using the penetrating shaft body, a plurality of permanent magnets and intermediate magnetic bodies can be securely fixed to the penetrating shaft body, a robust magnet movable body can be constructed, and the assembling work becomes easy. Further, by using the through shaft, it is not necessary to use a non-magnetic holder or the like that covers the outer circumference of the permanent magnet or the intermediate magnetic body in order to integrate a plurality of permanent magnets and the intermediate magnetic body. The thrust can be further improved by reducing the gap between the outer peripheral surface of the permanent magnet and each coil. Then, by supporting the penetrating shaft that functions as an output extracting pin of the magnet movable body by a bearing member having a fixed positional relationship with the triple coil, the movement of the magnet movable body can be smoothed. It is possible to realize a highly reliable movable magnet type actuator that has a small size, a small current and a large thrust.

[Brief description of drawings]

FIG. 1 shows a first movable magnet type actuator according to the present invention.
It is a right sectional view showing an example.

FIG. 2 is a side view of the same.

FIG. 3 is a front sectional view showing a second embodiment of the present invention.

FIG. 4 is a front sectional view showing a third embodiment of the present invention.

FIG. 5 is a front sectional view showing a fourth embodiment of the present invention.

FIG. 6 is a schematic configuration diagram of a reference example showing the basic operation principle of the present invention.

7 is a graph showing the relationship between the amount of displacement of a movable magnet body and thrust in the reference example of FIG.

FIG. 8 is a schematic configuration diagram showing a first conventional example.

FIG. 9 is a schematic configuration diagram showing a second conventional example.

FIG. 10 is a graph showing a vertical component (a component perpendicular to a longitudinal side surface) of a surface magnetic flux density on a longitudinal side surface (a surface parallel to a magnetizing direction of the permanent magnet) of a single permanent magnet.

FIG. 11 is a graph showing the vertical component of the surface magnetic flux density on the longitudinal side surface when two permanent magnets of the same pole facing each other are directly brought into contact with each other.

FIG. 12 is a graph showing the vertical component of the surface magnetic flux density on the longitudinal side surface when two permanent magnets are in the same pole facing state with an air gap of 1 mm.

FIG. 13 is a graph showing the vertical component of the surface magnetic flux density on the longitudinal side surface when two permanent magnets are in the state of facing each other with an air gap of 2 mm.

FIG. 14 is a graph showing the vertical component of the surface magnetic flux density on the longitudinal side surface when two permanent magnets are in the same pole facing state with an air gap of 3 mm.

FIG. 15 is a graph showing the vertical component of the surface magnetic flux density on the longitudinal side face when two permanent magnets are in the same pole facing state with a soft magnetic material interposed therebetween.

FIG. 16 is a graph showing the vertical component of the surface magnetic flux density on the longitudinal side face when two permanent magnets are in the same pole facing state with a soft magnetic material interposed and a soft magnetic material yoke is arranged.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylindrical yoke 2A, 2B, 2C Coil 3, 3A Magnet movable body 4 Guide cylinder 5 Cylindrical permanent magnet 6 Cylindrical middle part soft magnetic material 7A, 7B Cushion plate 8 Penetration shaft 9 Engagement groove 20 Stopper 21A , 21B, 21C, 21D Side plate 22 Bearing member 24 Compression spring 25 Return permanent magnet 26 End soft magnetic material

Claims (6)

[Scope of utility model registration request] 1. The permanent magnet and the intermediate magnetic body are fixed to a penetrating shaft body that penetrates at least two permanent magnets facing each other with the same pole and the intermediate magnetic body arranged between the permanent magnets. A magnet movable body is configured, the through shaft body is slidably supported by a bearing member, and the magnet movable body is movably provided inside at least three continuous coils. A movable magnet actuator characterized in that wires are connected so that currents flow in different directions with the magnetic poles of the magnets as boundaries. 2. The movable magnet type actuator according to claim 1, wherein end magnets are provided on outer end surfaces of permanent magnets located at both ends of the magnet movable body. 3. The movable magnet type actuator according to claim 1 or 2, wherein a magnetic attraction body that attracts the movable magnet body is disposed at at least one end of a guide cylindrical body to which the at least three continuous coils are fixed. 4. The movable magnet type actuator according to claim 1, wherein a spring for pushing back the magnet movable body is arranged at an end position of the guide cylinder body to which the at least three continuous coils are fixed. 5. The movable member according to claim 1, wherein a returning permanent magnet that generates a repulsive force with respect to the movable magnet body is provided at an end position of a guide cylinder body to which the at least three continuous coils are fixed. Magnetic actuator. 6. The movable magnet type actuator according to claim 1, wherein the permanent magnet and the intermediate magnetic body are fixed to the through shaft by a retaining ring that engages with the through shaft.