JP6192305B2 - Permanent magnet type electromagnetic drive - Google Patents

Description

  The present invention relates to an electromagnetic drive device using a permanent magnet, and more particularly to an electromagnetic drive device suitable for use as a vibration generation source in a material tester, a fatigue tester, a vibration tester, a vibration generator, and the like.

  As a vibration generation source in a material testing machine, a fatigue testing machine, a vibration testing machine, an exciter, etc., those using a hydraulic servo system using a piston and a cylinder are known. In general, hydraulic servo type material testing machines, fatigue testing machines, etc. are used to cool the hydraulic oil and hydraulic oil consisting of hydraulic pumps, hydraulic tanks, etc., as well as pistons and cylinders of the main body as components. A cooling device such as a cooling tower is essential. Therefore, when the hydraulic servo system is adopted, the installation itself is not realistic unless the device is large to some extent, and even a small device tends to be larger than necessary. Moreover, it becomes a big burden also in terms of maintenance management including the maintenance of the quality of hydraulic oil.

  On the other hand, medium and large vibration testing machines employ an electromagnetic system using a circular electromagnet magnetic circuit. In a vibration testing machine using a circular electromagnet magnetic circuit, it is necessary to pass a current through an exciting coil in order to generate magnetism. For this reason, an electromagnet magnetic circuit requires an excitation power source and further requires constant cooling. Therefore, a cooling blower with a large air flow is required even for short-time operation and low-power operation, and noise countermeasures for the cooling blower are inevitable, and power consumption for that purpose cannot be ignored.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a permanent magnet type electromagnetic drive device having a larger thrust and a high reproduction accuracy of an output acceleration waveform or displacement waveform.

  The specific problem of the present invention is realized in a conventional permanent magnet type electromagnetic drive device by adopting an efficient closed magnetic circuit that minimizes leakage magnetic flux and a neodymium magnet that is a rare earth magnet having a high maximum energy product. It is an object of the present invention to provide a permanent magnet type electromagnetic drive device which can obtain a long stroke and a large thrust which have been difficult.

  According to an aspect of the present invention, a pair of permanent magnet bodies are assembled such that a plurality of block-shaped neodymium magnets are arranged and fixed on one side of a magnetic plate, and the magnetic pole surfaces of the neodymium magnets are opposed to each other. A pair of yokes provided so as to be interposed between both ends of the pair of magnetic plates, and a pair of poles attached so as to cover all the magnetic pole surfaces of the plurality of neodymium magnets arranged in alignment A magnetic pole material and a central magnetic pole made of a magnetic material spanned between the pair of yokes so as to be interposed between the magnetic pole surfaces of the plurality of neodymium magnets in the pair of permanent magnet bodies facing each other And a fixed part including the movable body, and a movable wire ring assembled so as to contain the central magnetic pole body, and reciprocating due to an interaction between a current flowing through the movable wire ring and a magnetic flux generated by the pair of permanent magnet bodies. Vibrate Wherein a fixing portion combined movable portion, a permanent magnet-type electromagnetic drive device, characterized in that it comprises a are provided so.

  In the permanent magnet type electromagnetic drive device, one of the pair of permanent magnet bodies includes one of the neodymium magnet, the gap, the central magnetic pole body, the pair of yokes, the one magnetic plate, and the neodymium magnet. In addition to forming a circuit, the other magnetic circuit of the neodymium magnet, the gap, the central magnetic pole body, the pair of yokes, the other magnetic plate, and the neodymium magnet is formed on the other of the pair of permanent magnet bodies. And covering the entire outer circumference of the central magnetic pole body contained in the movable wire inserted in the gap of the one magnetic circuit and the gap of the other magnetic circuit with a metal plate having a low electrical resistance. Therefore, it is desirable to use a magnetic circuit to which an electrical short circuit is added.

  In the permanent magnet type electromagnetic drive device, a column is attached to each of the pair of yokes, a guide shaft extending in the same direction as the reciprocating vibration direction is spanned between the pair of columns, and the guide shaft is moved to the movable portion. It is desirable to constitute the guide mechanism of the movable part by supporting it with a bearing provided in the part.

  In the above permanent magnet type electromagnetic drive device, as a movable conducting wire for guiding an electric current to the movable wire ring, a resin coated wire of a very fine stranded wire excellent in flexibility is molded so as to be folded in a zigzag shape at an appropriate pitch. It is desirable to provide a movable lead guide mechanism in which the foldable movable lead is housed in a box-shaped guide made of a resin having little mutual friction.

  In the permanent magnet type electromagnetic drive device, the mechanical zero point position of the movable part is maintained by a structure in which the movable part is pulled by a string-like elastic rubber from the front part and the rear part of the fixed part. It is desirable to provide a center holding mechanism for the purpose.

  According to the present invention, the adoption of an efficient closed magnetic circuit that minimizes leakage magnetic flux and a neodymium magnet, which is a rare earth magnet having a high maximum energy product, is difficult to achieve with a conventional permanent magnet electromagnetic drive device. It is possible to provide a permanent magnet type electromagnetic drive device capable of generating a long stroke and a large thrust.

It is the perspective view which showed the principal part of the permanent magnet type electromagnetic drive device which concerns on embodiment of this invention. It is the perspective view which showed the principal part of the permanent magnet type electromagnetic drive device shown by FIG. 1 except the one part component. It is the perspective view which showed the movable part in the permanent magnet type electromagnetic drive device shown by FIG. It is the perspective view which showed the magnetic circuit part used as a fixing | fixed part in the permanent magnet type electromagnetic drive device shown by FIG. FIG. 5 is an exploded perspective view of the magnetic circuit unit shown in FIG. 4. FIG. 4 is a front view (FIG. A), a longitudinal sectional view (FIG. B), a transverse sectional view (FIG. C), and an enlarged view of a D portion of FIG. d). 1 is an external view of a permanent magnet type electromagnetic drive device according to an embodiment of the present invention.

(Concept of invention)
Before describing embodiments of the present invention, the concept of the present invention will be described.

  The permanent magnet type electromagnetic drive device according to the present invention includes a fixed portion by a closed magnetic circuit and a movable portion by a movable wire ring. In particular, the permanent magnet type electromagnetic drive device is premised on the use of a neodymium magnet, which is a rare earth magnet having a high maximum energy product, as a permanent magnet for constituting a closed magnetic circuit. In adopting a neodymium magnet, it is technically difficult to manufacture a large neodymium magnet. Therefore, when manufacturing a medium-sized or large-sized magnetic circuit, it is necessary to use it as a medium-sized or large-sized magnet by arranging a plurality of small magnets in parallel and fixing them. When a magnetic circuit is configured by arranging a plurality of small magnets, the number of joints between the magnets increases, and an arrhythmia of magnetic flux distribution appears at the joints. The arrhythmia adversely affects the reproduction accuracy of the output acceleration waveform or displacement waveform during operation of the permanent magnet type electromagnetic drive device, and further increases the leakage magnetic flux.

  As a countermeasure against such an arrhythmia, the arrhythmia is removed by fixing a magnetic plate having an appropriate thickness as a magnetic shunt plate to the entire magnetic pole surface of a plurality of small magnets. The magnetic shunt plate fixed to the entire magnetic pole face of a plurality of small magnets is also very effective for protecting the surface of a neodymium magnet that is vulnerable to impact and corrosion.

  Next, a short circuit in the same direction as the winding direction of the movable wire ring is formed by covering the magnetic pole of the permanent magnet in the closed magnetic circuit with a thin plate of a good conductor, and the induced current due to the current flowing in the movable wire ring is reduced. By flowing through this short circuit, a part of the AC resistance of the movable wire ring is canceled, and the burden on the drive power supply is reduced.

  When operating with a long stroke, which is a feature of the permanent magnet type electromagnetic drive device according to the present invention, a movable conductor is required to pass a current through a movable wire wheel that reciprocates with a long stroke. It is desirable that the movable conductor is housed compactly in the driving device without obstructing the movement of the movable portion. In the permanent magnet type electromagnetic drive device according to the present invention, a cable formed by heat-molding a resin-coated electric wire such as nylon and a very fine braided wire cable resistant to repeated bending stress in a zigzag manner at an appropriate pitch is used as a movable lead. use. In particular, as a place for installing the movable lead, an accommodation place for the movable lead is secured on at least one of the left and right sides of the fixed portion, and the place corresponding to the upper side and the lower side of the movable lead is provided with friction. By installing a guide with a rectangular pocket made of resin with a small amount of resin, a movable lead guide mechanism is constructed that can reciprocate by moving the movable lead smoothly in the guide.

  In the permanent magnet type electromagnetic drive device according to the present invention, when the movable part reciprocates, the displacement signal of the displacement meter attached to the movable part is input to the movable wire wheel in order to maximize the reciprocating stroke. The signal is negatively fed back, and the mechanical center position (zero position) of the movable part is held by a closed servo loop control system. Since the closed servo loop control system is not the gist of the present invention, illustration and description thereof are omitted.

  In the permanent magnet type electromagnetic drive device according to the present invention, in order to ensure safety, a general machine is constructed by pulling the movable part with a plurality of string-like elastic rubbers using the fixed ends of the fixed part as front and rear fixed points. A center holding mechanism that holds a typical center point (zero point) is employed. The elastic rubber is accommodated on the left and right sides of the same fixed portion as the movable conductive wire. In this way, it is possible to prevent the risk of damaging the device or the sample due to the movable part colliding with the fixed part due to the inertial force even in the event of an unforeseen situation such as a power failure or disconnection in the servo loop. As this kind of danger prevention means, conventionally, a method of absorbing collision energy with a buffer rubber for a stopper, etc. has been adopted, but by using such a method together with the method according to the present invention, safer operation is possible. Become.

(Embodiment of the Invention)
With reference to FIGS. 1-6, the permanent magnet type electromagnetic drive device which concerns on embodiment of this invention is demonstrated.

  FIG. 1 shows a permanent magnet type electromagnetic drive device according to an embodiment of the present invention with its outer cover removed. The fixing portion includes a closed magnetic circuit 10, front columns 21 and rear columns 22 fixed to both ends in the longitudinal direction, and a guide shaft 23 spanned between the front columns 21 and the rear columns 22. . The guide shaft 23 is used to guide a reciprocating operation associated with vibration of the movable part described later, and is also provided between the front column 21 and the rear column 22 on the opposite side to the illustrated location. Hereinafter, the longitudinal direction of the closed magnetic circuit 10 is referred to as the front-rear direction, both sides of the longitudinal direction are referred to as front-rear, the lateral direction perpendicular to the front-rear direction is referred to as the left-right direction, and both sides in the left-right direction are referred to as left-right. The direction perpendicular to is called the up-down direction.

  2 removes components such as the movable lead 31 and the elastic rubbers 32a and 32b from the permanent magnet type electromagnetic drive device shown in FIG. 1 in order to facilitate understanding of the permanent magnet type electromagnetic drive device shown in FIG. It shows in the state.

  1 and 2, the permanent magnet type electromagnetic drive device includes the above-described fixed portion and movable portion. The movable portion includes a U-shaped frame 41 in which legs 41-1 and 41-2 are attached to both sides of an operating piece 40 for extracting vibrations with bolts and the like, and two legs 41- of the frame 41. 1 and 41-2 and the movable wire ring 42 wound around the open end side. Each of the leg portions 41-1 and 41-2 has projecting portions projecting outward at two places with the winding portion of the movable wire ring 42 therebetween, and these two projecting portions include a guide shaft. 23 bearings 43a and 43b are mounted. In the vicinity of the two protrusions, pins 44a and 44b are respectively provided above and below them. Also, pins 21a and 22a similar to the pins 44a and 44b are provided on the upper and lower sides of the left and right side ends of the front column 21 and the rear column 22, respectively. Between the upper pin 21a of the front column 21 and the upper pin 44b closer to the rear column 22, and between the lower pin 22a of the rear column 22 and the lower pin 44a closer to the front column 21 Each is stretched in a state where the ring-shaped elastic rubbers 32a and 32b are stretched, that is, in a state where a tensile force is applied.

  The bearings 43a and 43b and the elastic rubbers 32a and 32b are also provided on the left and right sides of the closed magnetic circuit 10, that is, between the front column 21 and the rear column 22 on the opposite side of the illustrated location.

  In order to supply electric power to the movable wire ring 42, the movable conductive wire 31 is provided from the rear column 22 toward the movable wire ring 42, and is connected to the starting end of the winding of the movable wire ring 42. In particular, the movable conducting wire 31 is made of a resin coating such as nylon in order to supply electric power to the movable wire ring 42 without interfering with the reciprocating motion associated with the vibration in the front-rear direction of the movable portion and ensuring a long stroke of the movable portion. An extremely fine braided wire cable that is an electric wire and is resistant to repeated bending stress is heat-molded so that it can be folded in a zigzag shape at an appropriate pitch.

  In addition, by installing guides 45a and 45b having rectangular pockets made of resin with little friction in the longitudinal direction at locations corresponding to the upper side and the lower side of the movable lead 31 at the place where the movable lead 31 is installed, respectively. The movable conducting wire 31 constitutes a movable conducting guide mechanism capable of reciprocating by smoothly expanding and contracting in the guides 45a and 45b.

  The movable lead wire connected to the end of the movable wire ring 42 may be installed on the same side as the movable lead wire 31 so as to be parallel to the illustrated movable lead wire 31, but the balance of the reciprocating motion accompanying the vibration of the movable part is balanced. In consideration, like the bearing and the elastic rubber, it is preferably provided on the left and right sides of the closed magnetic circuit 10, that is, on the opposite side to the illustrated location.

  FIG. 3 shows the movable part removed from the permanent magnet type electromagnetic drive shown in FIG.

  FIG. 4 is a view showing the closed magnetic circuit 10 removed from the fixed portion in the permanent magnet type electromagnetic drive device shown in FIG. 2, and FIG. 5 is an exploded perspective view of the closed magnetic circuit 10. is there. 6 (a) is a front view of the closed magnetic circuit 10, FIG. 6 (b) is a cross-sectional view taken along the line AA 'of FIG. 6 (a), and FIG. 6 (c) is a diagram of FIG. 6 (a). FIG. 6 (d) is an enlarged view of a portion D in FIG. 6 (b). 6A is substantially the same as the arrow along the BB ′ section, and is not shown.

  4 to 6, the closed magnetic circuit 10 is provided so as to be interposed between the upper magnetic pole plate 11, the lower magnetic pole plate 12, and the front and rear ends of the upper magnetic pole plate 11 and the lower magnetic pole plate 12, respectively. A plurality of block-shaped neodymium magnets 16a provided on the lower surface of the upper magnetic pole plate 11 so as to be lined up in the front-rear and left-right directions, The lower magnetic pole plate 12 includes a plurality of block-like neodymium magnets 16b provided on the upper surface of the lower magnetic pole plate 12 so as to be arranged in the front-rear and left-right directions in the same arrangement pattern as the neodymium magnets 16a. The upper magnetic pole plate 11, the lower magnetic pole plate 12, the yokes 13 and 14, and the central magnetic pole body 15 are all made of a magnetic material. The neodymium magnets 16 a and 16 b are arranged so that the N pole faces the central magnetic pole body 15 with a predetermined gap. Magnetic shunt plates 17a and 17b are attached to the magnetic pole end faces of the neodymium magnets 16a and 16b, respectively. On the other hand, a short ring 18 made of a good conductor having a small electric resistance is wound around the central magnetic pole body 15 so as to cover the four surfaces of the upper, lower, left and right sides. As a result, the closed magnetic circuit 10 includes a neodymium magnet 16a-central magnetic pole body 15- yoke 14 and 15-upper magnetic pole plate 11-neodium magnet 16a magnetic circuit by a magnetic flux flow indicated by an arrow in FIG. And a neodymium magnet 16b-a central magnetic pole body 15-a yoke 14 and a 15-lower magnetic pole plate 12-a neodymium magnet 16b magnetic circuit. The gap between the neodymium magnets 16a and 16b and the central magnetic pole body 15 is short-circuited with the magnetic shunt plate 17a (17b) from the distance between the magnetic pole end face of the neodymium magnets 16a and 16b and the end face of the central magnetic pole body 15. It is defined by a value obtained by subtracting the thickness of the ring 18.

  Bolts are used to assemble the upper magnetic pole plate 11, the lower magnetic pole plate 12, the yokes 13 and 14, and the central magnetic pole body 15, and an adhesive is used to attach the neodymium magnets 16a and 16b.

  Returning to FIGS. 1 and 2, the movable part of the permanent magnet type electromagnetic drive device is mounted on the fixed part so that the central magnetic pole body 15 of the closed magnetic circuit 10 is inserted through the space inside the wire ring of the movable wire ring 42. The As a result, the movable wire ring 42 is interposed in the gap between the neodymium magnets 16 a and 16 b and the central magnetic pole body 15.

  Below, an example of the assembly operation | work of a movable part and a fixed part is demonstrated.

  (1) A movable part shown in FIG. 3 and a closed magnetic circuit shown in FIG. 4 are prepared. Although a guide shaft 23 is shown in FIG. 3 for easy understanding of the explanation, the guide shaft 23 is attached after the main assembly operation.

  (2) The yoke 13 is removed from the upper magnetic pole plate 11 and the lower magnetic pole plate 12 so that the central magnetic pole body 15 around which the short ring 18 is wound is passed through the movable wire ring 42. At this time, the upper magnetic pole plate 11 and the lower magnetic pole plate 12 are each held by a holding jig so that the interval shown in FIG. 4 can be maintained. Further, when removing the yoke 13, a large attractive force is exerted by the neodymium magnets 16a and 16b attached to the upper magnetic pole plate 11 and the lower magnetic pole plate 12, so a jig having a pulling force exceeding the attractive force is used. The yoke 13 is pulled out. After the yoke 13 is removed, the holding is performed so that the space between the upper magnetic pole plate 11 and the lower magnetic pole plate 12 is not narrowed by a large attractive force acting between the front ends of the upper magnetic pole plate 11 and the lower magnetic pole plate 12. Holding by the jig is maintained. The removed yoke 13 is temporarily placed in another place.

  (3) The movable part is combined with the fixed part so that the central magnetic pole body 15 passes through the movable wire ring 42.

  (4) The operating piece 40 is removed from the frame 41, and the yoke 13 is connected to the upper magnetic pole plate 11 and the lower magnetic pole plate 12 by utilizing the space between the two leg portions 41-1 and 41-2. Return to the original position in between. Subsequently, the operating piece 40 is returned to the frame 41 to be in the state shown in FIG. Although the guide shaft 23 is shown in FIG. 2 for easy understanding of the explanation, the guide shaft 23 is attached after the main assembly operation.

  (5) A front column 21 and a rear column 22 are attached to the front ends of the upper magnetic pole plate 11 and the lower magnetic pole plate 12, and to the rear ends of the upper magnetic pole plate 11 and the lower magnetic pole plate 12, respectively. Although this attachment is also performed with bolts, illustration is omitted. As is clear from FIG. 1, the front column 21 is provided with an opening 21-1 for projecting the operating piece 40 in the frame 41 of the movable portion outward. When the front column 21 and the rear column 22 are attached, the guide shaft 23 is also mounted through the bearings 43a and 43b. By this guide shaft 23, the force generated by the interaction between the magnetic force generated in the closed magnetic circuit 10 and the current flowing through the movable wire ring 42 is regulated in the direction in which the force is generated, that is, the extending direction of the guide shaft 23. It becomes.

  (6) The movable conducting wire 31 and the elastic rubbers 32a and 32b for constituting the center holding mechanism are mounted, and the tensile force of the elastic rubbers 312a and 32b and the movable part so that the movable part is at a middle position in the vibration range in a stationary state. Adjust the positional relationship.

  That is, the front column 21 and the rear column 22 at the end of the magnetic circuit are provided by a plurality of elastic rubbers 32a and 32b spanned between the pins 44a and 44b provided on the movable portion and the pins 21a and 22a provided on the fixed portion. By applying a tensile force in opposite directions with respect to the reference point, the moving center of the movable part can be held at a desired position (mechanical zero point position) while being displaceable in the front-rear direction.

  (7) The guides 45a and 45b are respectively attached to the upper and lower sides so as to accommodate the movable conducting wire 31, and an outer cover (not shown) is attached so as to cover the outer surface between the front column 21 and the rear column 22.

  FIG. 7 shows the appearance of the outer cover attached to the configuration of FIG. The outer cover 50-1, 50-2 covers at least both sides of the configuration shown in FIG. The working piece 40 protruding from the front column 21 is connected to a driven part when used in a vibration testing machine or a vibration generator, and provided with a mounting table on which a sample is placed when used in a material testing machine or a fatigue testing machine. It is done.

  The permanent magnet type electromagnetic drive device assembled as described above causes a current to flow to the movable wire ring 42 through the movable conducting wire 31, thereby causing an interaction between the current value and the magnetic field by the plurality of neodymium magnets 16 a and 16 b. A force that vibrates in the front-rear direction acts on the frame 41, that is, the movable portion, through the movable wire ring 42. Thereby, the vibration force can be taken out through the operating piece 40. Since such a vibration mode itself is well-known, detailed description is abbreviate | omitted. Further, the current flowing through the movable wire ring 42 may be only an alternating current component, (DC component + alternating current component), or only a direct current component. In the case of only the DC component, it is used as an electromagnetic drive device that obtains an operating force in one direction.

(Effect of embodiment)
As described above, the permanent magnet type electromagnetic driving device according to the embodiment of the present invention is not only a small and high performance permanent magnet type electromagnetic driving device but also a high performance of a closed type magnetic circuit using a neodymium magnet. The large-thrust and large-stroke permanent magnet type electromagnetic drive device, which was difficult with conventional permanent magnets, can be manufactured, and the permanent magnet type electromagnetic drive device is used in the field of electromagnet type electromagnetic drive device or hydraulic drive device. Thus, not only energy saving but also great effects such as space saving, noise reduction, and labor saving of maintenance can be obtained.

  The permanent magnet type electromagnetic drive device according to the present invention is suitable for application as a vibration generation source to a material testing machine, a fatigue testing machine, a vibration testing machine, a vibrator, and the like.

10 closed magnetic circuit 11 upper magnetic pole plate 12 lower magnetic pole plate 13, 14 yoke 15 central magnetic pole body 16a, 16b neodymium magnet 17a, 17b magnetic shunt plate 18 short ring 21 front column 22 rear column 23 guide shaft 31 movable conductor 32a, 32b Elastic rubber 40 Actuating piece 41 Frame 41-1, 41-2 Leg part 42 Movable wire ring 43a, 43b Bearing 45a, 45b Guide 50-1, 50-2 Outer cover

Claims (2)

A pair of permanent magnet bodies assembled such that a plurality of block-shaped neodymium magnets are arranged and fixed on one side of the magnetic plate, and the magnetic pole surfaces of the neodymium magnets are opposed to each other,
A pair of yokes provided so as to be interposed between both ends of the pair of magnetic plates;
A pair of magnetic shunts that are attached so as to cover all the magnetic pole faces of the plurality of neodymium magnets arranged in alignment and reduce the arrhythmia of the magnetic flux distribution generated at the boundary surface of the neodymium magnets and protect the surface of the neodymium magnets The board,
A central magnetic pole body made of a magnetic material spanned between the pair of yokes so as to be interposed between the magnetic pole faces of the plurality of neodymium magnets in the pair of permanent magnet bodies facing each other. A fixed part;
A movable wire ring assembled so as to contain the central magnetic pole body, and reciprocally vibrate as a vibration generation source due to an interaction between a current flowing through the movable wire ring and a magnetic flux generated by the pair of permanent magnet bodies. A movable part combined with a fixed part;
With
In one of the pair of permanent magnet bodies, one magnetic circuit of the neodymium magnet-gap-the central magnetic pole body-the pair of yokes-one of the magnetic plates-the neodymium magnet is formed, and the pair of permanent magnet bodies The other magnetic circuit of the neodymium magnet-gap-the central magnetic pole body-the pair of yokes-the other magnetic body plate-the neodymium magnet is formed in the other permanent magnet body,
Covering the entire outer surface of the central magnetic pole body included in the movable wire ring inserted in the gap of the one magnetic circuit and the gap of the other magnetic circuit directly with a metal plate having low electrical resistance. By adding an electrical short circuit that cancels part of the AC resistance of the movable wire ring and reduces the load on the drive power source of the movable wire wheel ,
Furthermore, as a movable conducting wire for guiding current to the movable wire ring, a resin-coated wire of a very fine stranded wire excellent in flexibility is molded so as to be foldable in a zigzag shape, and the foldable movable conducting wire is arranged on its upper side. A movable lead guide mechanism housed in a resin rectangular pocket guide with little friction on the lower side;
The movable part collides with the fixed part due to inertial force in the event of a power failure or disconnection of the movable lead wire by adopting a structure in which the movable part is pulled by a string-like elastic rubber from the front part and the rear part of the fixed part. And a center holding mechanism that holds the mechanical zero point position of the movable part . The permanent magnet electromagnetic drive device according to claim 1,
A column is attached to each of the pair of yokes, a guide shaft extending in the same direction as the reciprocating vibration direction is spanned between the pair of columns, and the guide shaft is supported by a bearing provided in the movable portion. A permanent magnet type electromagnetic drive device characterized in that a guide mechanism of a movable part is configured.

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