JP4610884B2 - Linear actuator - Google Patents

Description

  The present invention relates to a linear actuator that constitutes a generator or an electric motor by the cooperative action of a stator and a movable element that linearly reciprocates in the axial direction facing the stator.

A so-called linear generator is known as a typical technique of a linear actuator. As a conventional technique of this linear generator, a permanent magnet magnetized in a direction orthogonal to the direction of motion is used as a mover, and a stator is provided on both sides of the mover, and the direction of magnetic flux passing through the mover is indicated by a mover. A configuration is known that is orthogonal to the direction of motion of (see, for example, Patent Document 1).
Japanese Utility Model Publication No. 7-27825 (Claim 1 and FIG. 1)

However, a conventional generator requires a considerable amount of permanent magnets in order to output a predetermined capacity, and a neodymium magnet used as a permanent magnet is expensive and affects the weight.
Therefore, it is desirable to reduce the amount of permanent magnets used while maintaining a predetermined capacity in terms of cost reduction and weight reduction.

  Therefore, an object of the present invention is to reduce the amount of permanent magnets used while maintaining a predetermined capacity.

According to a first aspect of the present invention, a linear actuator according to the present invention is disposed on a concentric circle between an inner yoke formed in a cylindrical shape and an outer yoke formed in a cylindrical shape, and between the inner yoke and the outer yoke. and a permanent magnet that is, the coil is wound in the inner yoke or said outer yoke, lutein Isu to form a magnetic path between the other yoke on one yoke the coil is wound comprising a part, the teeth of only the pair for one of the yoke core is formed, between the pair of teeth are voids formed, one of the yoke of the permanent magnet and hand one mover, the other is a stator, the said yoke of the permanent magnet and the hand is a linear actuator for moving in the axial direction relatively cylindrical, both ends of the permanent magnet Respectively an auxiliary yoke through the magnetic resistance region, said permanent magnet when made to face the gap between one of the teeth, the teeth of the other faces the other of the auxiliary yoke, the permanent Magnetic flux radiated from the magnet travels from one of the tooth portions into the iron core, forms a magnetic path along the iron core, travels from the other tooth portion to the other auxiliary yoke, and the permanent magnet When the permanent magnet is opposed to the other tooth portion and the air gap when one of the teeth portions is one of the above-described ones, a voltage is induced by a change in magnetic flux interlinked with the coil. A magnetic flux radiated from the permanent magnet, facing the auxiliary yoke, travels from the other tooth portion into the iron core, forms a magnetic path along the iron core, and from one tooth portion to the other one Proceeds to aid the yoke, by returning to the permanent magnet, characterized in that it induces a voltage in the variation of the magnetic flux interlinked with the coil.
According to a second aspect of the present invention, in the linear actuator according to the first aspect, the magnetoresistive region is configured by a gas space.
A third aspect of the present invention is the linear actuator according to the first aspect, wherein the magnetoresistive region is made of a resin material.
According to a fourth aspect of the present invention, in the linear actuator according to the first aspect, the magnetoresistive region is formed of a permanent magnet having a magnetic pole direction different from that of the permanent magnet.
According to a fifth aspect of the present invention, in the linear actuator according to the first aspect, the axial length of the surface of the teeth portion facing the permanent magnet is ht, and the axial length of the auxiliary yoke is When the height is hy, the hy is 0.25 ht or more.
According to a sixth aspect of the invention, in the linear actuator according to claim 1, before Kite Isu unit consists narrow portion and which is connected with the wide portion which is formed across the gap between the wide portion When the length of the narrow portion in the axial direction is ha and the length of the auxiliary yoke in the axial direction is hy, hy is set to 0.75 ha or more.
According to a seventh aspect of the present invention, in the linear actuator according to the first aspect, the length of the auxiliary yoke in the direction perpendicular to the axis is wy, and the length of the permanent magnet in the direction perpendicular to the axis is set. When wm is set, wy is set to 0.93 wm or more.
The present invention of claim 8, wherein, in the linear actuator according to claim 1, before Kite Isu unit consists narrow portion and which is connected with the wide portion which is formed across the gap between the wide portion , When the axial length of the permanent magnet is hm, the axial length of the surface of the wide portion facing the permanent magnet is ht, and the axial length of the gap is slt, It is characterized in that hm is 0.87 (ht + slt) or more.
The present invention of claim 9, wherein, in the linear actuator according to claim 1, before Kite Isu unit consists narrow portion and which is connected with the wide portion which is formed across the gap between the wide portion When the axial length of the surface of the wide portion facing the permanent magnet is ht and the length of the axial movement stroke is strk, ht is 0.40 strk or more and 1.14 strk or less. It is characterized by.
The present invention of claim 10, wherein, in the linear actuator according to claim 1, before Kite Isu unit consists narrow portion and which is connected with the wide portion which is formed across the gap between the wide portion The distance between the surfaces of the pair of auxiliary yokes facing the permanent magnet is hg, the length of the gap in the axial direction is slt, and the length of the surface of the wide portion facing the permanent magnet is in the axial direction. Where hg is 0.85 (slt + 2ht) or more and 1.19 (slt + 2ht) or less.
The present invention of claim 11, wherein, in the linear actuator according to claim 1, before Kite Isu unit consists narrow portion and which is connected with the wide portion which is formed across the gap between the wide portion , The axial length of the permanent magnet is hm, the axial length of the gap is slt, the axial length of the surface of the wide portion facing the permanent magnet is ht, and the pair of the permanent magnets When the distance between the surfaces of the auxiliary yoke facing the permanent magnet is hg, hm = slt + ht and hg = slt + 2ht.
The present invention of claim 12, wherein, in the linear actuator according to any one of claims 1 to claim 11, characterized in that the movable element by connecting the yoke of the permanent magnet and the other side .
The present invention of claim 13, wherein the Te linear actuator smell of claim 12, and the yoke of the outer yoke other hand, characterized in that the yoke of the hand and the inner yoke.

According to the present invention, the efficiency is improved by the auxiliary yoke, and the amount of permanent magnets to be used can be reduced while maintaining a predetermined capacity.
Further, by connecting the permanent magnet and the outer yoke to form a mover, the actuator can be reduced in size by making the air gap between the mover and the stator one.

Linear actuator according to the first embodiment of the present invention, both ends of the permanent magnet, respectively an auxiliary yoke through the magnetic resistance region, when made to face a permanent magnet in one of the teeth and the gap The other tooth portion faces the other auxiliary yoke, and the magnetic flux radiated from the permanent magnet travels from one tooth portion into the iron core, forms a magnetic path along the iron core, and from the other tooth portion. By proceeding to the other auxiliary yoke and returning to the permanent magnet, a voltage is induced by a change in the magnetic flux linked to the coil, and when the permanent magnet is opposed to the other teeth portion and the gap, The part faces one auxiliary yoke, and the magnetic flux radiated from the permanent magnet travels from the other tooth part into the iron core, forms a magnetic path along the iron core, and from one tooth part to one auxiliary yoke. Progress and permanent By returning to the stone, by inducing a voltage in the variation of the magnetic flux interlinking the coil, it can be reliably caught by one of flux auxiliary yoke emitted through the magnetic path of the yoke from the permanent magnet Therefore, the output taken out as an actuator can be increased. Therefore, since the efficiency is improved by the auxiliary yoke, the amount of permanent magnets used can be reduced while maintaining a predetermined capacity. Further, the efficiency is further improved by providing auxiliary yokes at both ends.
In the second embodiment of the present invention, in the linear actuator according to the first embodiment, the magnetoresistive region is configured by a gas space, and the magnetoresistive region is formed without providing other materials. Thus, the weight can be reduced.
In the linear actuator according to the first embodiment, the third embodiment of the present invention further reduces the leakage magnetic flux from the permanent magnet to the auxiliary yoke by configuring the magnetoresistive region with a resin material. Can do.
According to the fourth embodiment of the present invention, in the linear actuator according to the first embodiment, the magnetoresistive region is formed of a permanent magnet having a magnetic pole direction different from that of the permanent magnet, so that the permanent magnet is changed to the auxiliary yoke. The leakage magnetic flux can be further reduced.
According to the fifth embodiment of the present invention, in the linear actuator according to the first embodiment, the axial length of the surface of the teeth portion facing the permanent magnet is ht, and the axial length of the auxiliary yoke is the same. When hy is used, hy is 0.25 ht or more. According to this embodiment, since the amount of magnetic flux captured by the auxiliary yoke can be increased, the output taken out as the actuator can be increased.
Sixth embodiment of the present invention, Te linear actuator odor according to the first embodiment, Te Isu unit is composed of a narrow portion which is connected with the wide portion and the wide portion which is formed across the gap When the axial length of the narrow portion is ha and the axial length of the auxiliary yoke is hy, hy is 0.75 ha or more. According to this embodiment, since the amount of magnetic flux captured by the auxiliary yoke can be increased, the output taken out as the actuator can be increased.
In the seventh embodiment of the present invention, in the linear actuator according to the first embodiment, the length in the direction perpendicular to the axis of the auxiliary yoke is wy, and the length in the direction perpendicular to the axis of the permanent magnet is wm. , Wy is 0.93 wm or more. According to the present embodiment, since the amount of magnetic flux captured by the auxiliary yoke can be increased by shortening the distance in the air gap, the output taken out as the actuator can be increased.
Eighth embodiment of the present invention, Te linear actuator odor according to the first embodiment, Te Isu unit is composed of a narrow portion which is connected with the wide portion and the wide portion which is formed across the gap When the length of the permanent magnet in the axial direction is hm, the length of the surface of the wide portion facing the permanent magnet in the axial direction is ht, and the length of the gap in the axial direction is slt, hm is 0.87 (ht + slt ) That's it. According to this embodiment, since the amount of magnetic flux captured by the auxiliary yoke can be increased, the output taken out as the actuator can be increased.
Ninth embodiment of the present invention, Te linear actuator odor according to the first embodiment, Te Isu unit is composed of a narrow portion which is connected with the wide portion and the wide portion which is formed across the gap When the length in the axial direction of the surface of the wide portion facing the permanent magnet is ht and the length of the moving stroke in the axial direction is strk, ht is 0.40 strk or more and 1.14 strk or less. According to this embodiment, since the amount of magnetic flux captured by the auxiliary yoke can be maximized, the output taken out as the actuator can be increased.
Tenth embodiment of the present invention, Te linear actuator odor according to the first embodiment, Te Isu unit is composed of a narrow portion which is connected with the wide portion and the wide portion which is formed across the gap When the distance between the surfaces of the pair of auxiliary yokes facing the permanent magnet is hg, the axial length of the air gap is slt, and the axial length of the surface facing the permanent magnet of the wide portion is ht, hg Is 0.85 (slt + 2ht) or more and 1.19 (slt + 2ht) or less. According to this embodiment, since the amount of magnetic flux captured by the auxiliary yoke can be maximized, the output taken out as the actuator can be increased.
Eleventh embodiment of the present invention, Te linear actuator odor according to the first embodiment, Te Isu unit is composed of a narrow portion which is connected with the wide portion and the wide portion which is formed across the gap The axial length of the permanent magnet is hm, the axial length of the air gap is slt, the axial length of the surface facing the permanent magnet of the wide portion is ht, and the permanent magnet faces the permanent magnet of the pair of auxiliary yokes. When the distance between the surfaces is hg, hm = slt + ht and hg = slt + 2ht. According to the present embodiment, it is possible to provide an optimum condition for reducing the size of an expensive permanent magnet and obtaining a large output.
The twelfth embodiment of the present invention is a linear actuator according to any of the first to eleventh embodiments, wherein a permanent magnet and the other yoke are connected to form a mover. According to this embodiment, since the air gap between the mover and the other yoke can be eliminated, it is possible to reduce the size and to ensure stable operation.
In a thirteenth embodiment of the present invention, in the linear actuator according to the twelfth embodiment, the other yoke is an outer yoke and one yoke is an inner yoke. According to the present embodiment, the weight can be reduced by setting the coil on the inner yoke side.

Embodiments of the present invention will be described below in detail with reference to the drawings.
FIG. 1 is a cross-sectional configuration diagram on one side of an embodiment of a linear actuator according to the present invention. In the linear actuator of the present embodiment, a permanent magnet 12 arranged in a cylindrical shape is attached to a central portion of one main surface (inner peripheral surface) of a yoke (outer yoke) 11 formed in a cylindrical shape. . Cylindrical auxiliary yokes 13 and 14 are provided at both ends of the yoke 11 via a permanent magnet 12 and a space (magnetic resistance region) 15. One of the auxiliary yokes 13 and 14 may be omitted. The yoke 10, the permanent magnet 12, and the auxiliary yokes 13 and 14 constitute a mover 10, which reciprocates in a moving direction (axial direction) 16 indicated by an arrow.
A stator (inner yoke) 20 formed in a cylindrical shape facing the mover 10 is arranged on a concentric circle. The stator 20 is configured by winding a coil 26 around an iron core 21 in which iron pieces having a U-shaped or annular plane are arranged in a cylindrical shape. The iron core 21 has a U-shaped or annular narrow portion 23 and wide portions 24 and 25 formed at both ends of the narrow portion 23, and a gap 22 is formed between the wide portions 24 and 25. Yes. A teeth portion is constituted by the wide portions 24 and 25 and a part of the narrow portion 23. The surface composed of the surface 241 of the wide portion 24, the surface 251 of the wide portion 25, and the gap 22 is a surface composed of the surface 121 of the permanent magnet 12, the surface 131 of the auxiliary yoke 13, and the surface 141 of the auxiliary yoke 14. Is facing.
The magnetoresistive region 15 of the mover 10 preferably has a high magnetic resistance in order to prevent the magnetic flux from the permanent magnet 12 from leaking to the auxiliary yokes 13 and 14. Specifically, the space may be a gas space, but it is necessary to secure a certain space length between the permanent magnet 12 and the auxiliary yokes 13 and 14 in order to obtain a predetermined magnetic resistance. In addition, you may interpose the permanent magnet from which the direction of a magnetic pole differs from resin material or the permanent magnet 12 instead of space.

In this embodiment, the yoke 11 and the permanent magnet 12 are integrally provided. However, a gap is provided between the yoke 11 and the permanent magnet 12, and only the permanent magnet 12 is configured as a mover. Also good. Alternatively, the stator 20 side may be a movable element, and the yoke 11 and the permanent magnet 12 may be configured as a stator.
Further, the stator 20 may be configured as an outer yoke, and the yoke 11 may be configured as an inner yoke. Even in this case, a gap may be provided between the yoke 11 and the permanent magnet 12, and only the permanent magnet 12 may be configured as a mover. Alternatively, the stator 20 side may be a movable element, and the yoke 11 and the permanent magnet 12 may be configured as a stator.

Next, the operation will be described. FIG. 2A shows a state where the mover 10 has moved to the lowest position. When the mover 10 moves downward along the arrow 16 in FIG. 1, the permanent magnet 12 of the mover 10 moves into the gap 22 formed in the iron core 21 of the stator 20 and the wide portion (tooth portion) 25 of the iron core 21. opposite. At this time, the magnetic flux radiated from the permanent magnet 12 proceeds from the wide portion 25 into the iron core 21, forms a magnetic path 28 along the iron core 21, and proceeds from the other wide portion 24 to the auxiliary yoke 13. The magnetic flux that has entered the auxiliary yoke 13 forms a magnetic path 28 in the yoke 11 and returns to the permanent magnet 12. At this time, a change in magnetic flux linked to the coil 26 wound around the stator 20 induces a voltage to generate power.
When the mover 10 is moved upward from the state of FIG. 2A and the center of the permanent magnet 12 of the mover 10 coincides with the center of the gap 22 of the stator 20 as shown in FIG. 2B. The magnetic flux radiated from the permanent magnet 12 is equally incident on the wide portions 24 and 25 of the stator 20. Therefore, since magnetic flux flows uniformly in the forward direction and the reverse direction in the magnetic path 28 of the stator 20, the two cancel each other.
If the mover 10 is further moved upward from the state of FIG. 2B and moved to the uppermost position, the state of FIG. 2C is obtained. In the state of FIG. 2C, the permanent magnet 12 of the mover 10 faces the gap 22 and the wide portion 24 formed in the stator 20. At this time, the magnetic flux radiated from the permanent magnet 12 proceeds from the wide portion 24 into the iron core 21, forms a magnetic path 28 along the iron core 21, and proceeds from the other wide portion 25 of the iron core 21 to the auxiliary yoke 14. To do. That is, it proceeds in the opposite direction to FIG. The magnetic flux that has entered the auxiliary yoke 14 returns to the permanent magnet 12 by forming a magnetic path 28 in the yoke 11. At this time, a change in magnetic flux linked to the coil 26 wound around the stator 20 induces a voltage to generate power. The voltage at this time is opposite in polarity to the voltage induced in FIG.

When the mover 10 is moved downward again, the state shown in FIG. 2A is obtained. When the mover 10 is reciprocated in the moving direction 16 shown in FIG. 1, FIG. 2A → FIG. 2B → FIG. 2 (c) → FIG. 2 (b) → FIG. 2 (a) → FIG. 2 (b) → FIG. 2 (c) →... As a result, as shown in FIG. 3, the coil 26 is induced with a sine wave voltage whose phase is shifted by 90 deg with respect to the change in the magnetic flux, so that sine wave power is generated. 3, (a) shows the state of FIG. 2 (a), (b) shows the state of FIG. 2 (b), and (c) shows the state of FIG. 2 (c).
The dimensions of the permanent magnet 12, the auxiliary yokes 13 and 14, the teeth portion, and the air gap 22 affect the magnitude of the voltage induced in the coil 26. Therefore, the dimensional relationship among the permanent magnet 12, the auxiliary yokes 13 and 14, the tooth portion, and the gap 22 will be described in detail below.

  FIG. 4 is a characteristic diagram showing the relationship between the length of the auxiliary yoke 13 and the length of the wide portion 24, the relationship between the length of the auxiliary yoke 14 and the length of the wide portion 25, and the magnitude of the voltage induced in the coil 26. It is. As shown in FIG. 1, the length in the moving direction 16 of the movable element 10 on the surfaces 241 and 251 of the wide width parts 24 and 25 facing the movable element 10 (corresponding to the height when the moving direction is the vertical direction). ) And the length of the auxiliary yokes 13 and 14 in the same movement direction 16 (corresponding to the height when the movement direction is the vertical direction) is hy, and when hy / ht is 0.25 or more, The output ratio of the induced voltage is 90% or more. When hy / ht is 0.25 or less, the output ratio decreases rapidly. In addition, when hy / ht is 0.32 or more and 0.9 or less, the output ratio is more preferably 100% or more.

  FIG. 5 is a characteristic diagram showing the relationship between the relationship between the lengths of the auxiliary yokes 13 and 14 and the length of the narrow width portion 23 and the magnitude of the voltage induced in the coil 26. As shown in FIG. 1, the length in the moving direction 16 of the mover 10 at the distal end portion of the narrow portion 23, that is, the connecting portion with the wide portions 24 and 25 (height when the moving direction is the vertical direction). Hy / ha is 0.75 or more, where ha is the length of the auxiliary yokes 13 and 14 in the moving direction 16 (corresponding to the height when the moving direction is the vertical direction). Then, the output ratio of the induced voltage is 90% or more. When hy / ha is 0.75 or less, the output ratio decreases rapidly. Further, when hy / ha is 1 or more and 2.7 or less, the output ratio is more preferably 100% or more.

  FIG. 6 shows the relationship between the thickness of the auxiliary yokes 13 and 14, that is, the length in the direction of extension to the stator 20 (direction perpendicular to the axis) and the thickness of the permanent magnet 12, that is, the length in the direction of extension. FIG. 6 is a characteristic diagram showing the relationship between the voltage and the magnitude of the voltage induced in the coil 26. As shown in FIG. 1, the length of the auxiliary yokes 13 and 14 in the extending direction (corresponding to the thickness when viewed from the surface of the yoke 11) is wy, and the length of the permanent magnet 12 in the extending direction (yoke 11 is equivalent to the thickness when viewed from the surface of 11, where wm is 0.93 or more, the output ratio of the induced voltage is 90% or more. Therefore, it is preferable that wy / wm is 0.93 or more.

FIG. 7 is a characteristic diagram showing the relationship between the relationship between the length of the permanent magnet 12, the length of the air gap 22, the length of the wide portions 24 and 25, and the magnitude of the voltage induced in the coil 26. As shown in FIG. 1, the length of the permanent magnet 12 in the movement direction 16 of the mover 10 (corresponding to the height when the movement direction is the vertical direction) is hm, and the mover 10 of the wide portions 24 and 25. , The length in the moving direction 16 of the mover 10 on the surfaces 241 and 251 (corresponding to the height when the moving direction is the vertical direction) is ht, and the distance between the gaps 22 in the iron core 21 (the moving direction is the vertical direction). When hm / (ht + slt) is 0.87 or more, the output ratio of the induced voltage is 90% or more. Therefore, it is preferable that hm / (ht + slt) is 0.87 or more.
According to FIG. 7, the larger the length hm of the permanent magnet 12, the larger the output ratio can be obtained. However, in realizing the linear actuator, when the length of the permanent magnet 12 is increased, the mover 10 is correspondingly increased. In addition, since the material used for the permanent magnet 12 is made of an expensive material such as neodymium, a smaller one is preferable. Therefore, practically, it is preferable to set hm = ht + slt.

  FIG. 8 is a characteristic diagram showing the relationship between the lengths of the wide portions 24 and 25 and the movement stroke of the mover 10 and the magnitude of the voltage induced in the coil 26. As shown in FIG. 1, the length in the moving direction 16 of the movable element 10 on the surfaces 241 and 251 of the wide portions 24 and 25 facing the movable element 10 (corresponding to the height when the moving direction is the vertical direction). ) Is ht and the length of the moving stroke of the mover 10 is strk, the output ratio of the induced voltage is 90% or more when ht / strk is 0.40 or more and 1.14 or less. When ht / strk is out of this range, the output ratio decreases rapidly. Therefore, ht / strk is preferably 0.40 or more and 1.14 or less. Furthermore, ht / strk is preferably 0.50 or more and 1 or less, and ht / strk is preferably 0.64 or more and 0.85 or less.

  FIG. 9 is a characteristic diagram showing a relationship between the relationship between the gap between the auxiliary yokes 13 and 14, the length of the gap 22 and the lengths of the wide portions 24 and 25, and the magnitude of the voltage induced in the coil 26. As shown in FIG. 1, the distance between the inner wall surface of the auxiliary yoke 13 facing the permanent magnet 12 and the inner wall surface of the auxiliary yoke 14 facing the permanent magnet 12 is hg, facing the mover 10 of the wide portions 24 and 25. The length in the moving direction 16 of the mover 10 on the surfaces 241 and 251 to be moved (corresponding to the height when the moving direction is the vertical direction) is ht, and the distance between the gaps 22 of the iron core 21 (the moving direction is the vertical direction). In some cases, corresponding to the height) is set to slt, and when hg / (2ht + slt) is 0.85 or more and 1.19 or less, the output ratio of the induced voltage is 90% or more. Therefore, it is preferable that hg / (2ht + slt) is 0.85 or more and 1.19 or less. Furthermore, it is preferable that hg / (2ht + slt) is 1.00 or more and 1.05 or less. In particular, since the output ratio becomes maximum in the vicinity of hg = 2ht + slt, it is preferable to set hg = 2ht + slt as an actual linear actuator.

As described above, the permanent magnet 12 is preferably small because an expensive material such as neodymium is used. On the other hand, it is necessary to increase the output with the small permanent magnet 12. Therefore, the optimum dimensions of the permanent magnet 12 are preferably hm = slt + ht and hg = slt + 2ht from FIG. 7 and FIG.
4 to 9, the stator 20 in FIG. 1 is the outer yoke, the yoke 11 is the inner yoke, the distance from the shaft center to the inner peripheral surface of the yoke 11 is 53 mm, and the shaft center to the inside of the stator 20 is the same. 67.5 mm to the peripheral surface, 90 mm from the axial center to the outer peripheral surface of the stator 20, the thickness of the yoke 11 is 8 mm, the gap depth of the stator 20 is 3 mm, and the outer peripheral side thickness of the iron core 21 of the stator 20 Is a fixed value with 5 mm as a reference value, and hereafter, when ht is 18 mm, hy is 6 mm, ha is 6 mm, wy is 6 mm, wm is 6 mm, hm is 28 mm, slt is 10 mm, strk is 18 mm, and hg is 46 mm The ratio when the characteristic is 100. In this case, an output of about 1 kw could be obtained at an output ratio of 90%.

  The linear actuator according to the present invention is useful as a power generation unit of various small generators and electric motors, particularly Stirling engines.

Cross-sectional configuration diagram of the main part of a linear actuator in an embodiment of the present invention BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing explaining operation | movement of the linear type actuator in the Example of this invention, (a) is a figure which shows the state which moved the needle | mover to the lowest part, (b) is the center of the permanent magnet of a needle | mover, and stator The figure which shows the state which the center of the space | gap corresponded, (c) is the figure which shows the state which the needle | mover moved to the top Voltage waveform diagram induced in the coil of the linear actuator in the embodiment of the present invention The characteristic view which shows the relationship between the length of the auxiliary yoke in the linear actuator in the Example of this invention, the length of a wide part, and the magnitude | size of the voltage induced in a coil The characteristic view which shows the relationship between the length of the auxiliary yoke in the linear actuator in the Example of this invention, the length of a narrow part, and the magnitude | size of the voltage induced in a coil The characteristic view which shows the relationship between the thickness of the auxiliary yoke in the linear actuator in the Example of this invention, the thickness of a permanent magnet, and the magnitude | size of the voltage induced in a coil The characteristic view which shows the relationship between the length of the permanent magnet in the linear actuator in the Example of this invention, the length of the space | gap of a yoke, the length of a wide part, and the magnitude | size of the voltage induced in a coil The characteristic view which shows the relationship between the magnitude | size of the voltage induced by the length of the wide part in the linear actuator in the Example of this invention, the moving stroke of a needle | mover, and a coil The characteristic view which shows the relationship between the magnitude | size of the voltage induced by the clearance gap between the auxiliary yokes in the Example of this invention, the length of the clearance gap of a yoke, and the length of a wide part, and the coil.

DESCRIPTION OF SYMBOLS 10 Movable element 11 Yoke 12 Permanent magnet 13, 14 Auxiliary yoke 15 Magnetoresistive area 18 Magnetic path 20 Stator 21 Iron core 22 Air gap 23 Narrow part 24, 25 Wide part 26 Coil 28 Magnetic path 121 Surface of permanent magnet 131, 141 Auxiliary Yoke surface 241, 251 Wide surface

Claims (13)

A yoke portion comprising a cylindrical inner yoke and a cylindrical outer yoke; and a permanent magnet disposed concentrically between the inner yoke and the outer yoke, the inner yoke or coil is wound around the outer yoke, the one yoke which said coil is wound comprises a ruthenate Isu portion to form a magnetic path between the other yoke, with respect to one of the yoke core are formed teeth of the pair only, between the pair of teeth are formed voids, one of the yoke of the permanent magnet and hand mover, the other is a stator, the permanent and the yoke of the magnet and the hand is a linear actuator for moving in the axial direction relatively cylindrical,
Both ends of the permanent magnets, provided respectively auxiliary yoke through the magnetic resistance region,
When the permanent magnet is opposed to one of the tooth portions and the gap, the other tooth portion is opposed to the other auxiliary yoke, and the magnetic flux radiated from the permanent magnet is generated from the one tooth portion. Proceeding into the iron core, forming a magnetic path along the iron core, proceeding from the other tooth portion to the other auxiliary yoke, and returning to the permanent magnet, the magnetic flux interlinked with the coil A change induces a voltage,
When the permanent magnet is opposed to the other tooth portion and the gap, one of the tooth portions faces one of the auxiliary yokes, and the magnetic flux radiated from the permanent magnet is changed to the other tooth portion. From the one tooth portion to one of the auxiliary yokes and returning to the permanent magnet so that the magnetic flux interlinks with the coil. A linear actuator characterized in that a voltage is induced by a change in the angle.   The linear actuator according to claim 1, wherein the magnetoresistive region is configured by a gas space.   The linear actuator according to claim 1, wherein the magnetoresistive region is made of a resin material.   The linear actuator according to claim 1, wherein the magnetoresistive region is formed of a permanent magnet having a magnetic pole direction different from that of the permanent magnet.   When the axial length of the surface of the teeth portion facing the permanent magnet is ht and the axial length of the auxiliary yoke is hy, hy is 0.25 ht or more. The linear actuator according to claim 1. Before Kite Isu unit is composed of a wide portion which is formed across the gap between the wide portion and connecting the narrow portion, the length of the axis direction of the narrow portion ha, the said auxiliary yoke The linear actuator according to claim 1, wherein when the axial length is hy, hy is 0.75 ha or more.   The length of the auxiliary yoke in the direction perpendicular to the axis is wy, and the length of the permanent magnet in the direction perpendicular to the axis is wm, wherein wy is 0.93 wm or more. The linear actuator according to 1. Before Kite Isu unit consists of a wide portion which is formed across the gap between the wide portion and connecting the narrow portion, the axial length of the permanent magnet hm, the permanent of the wide portion The hm is 0.87 (ht + slt) or more, where ht is the axial length of the surface facing the magnet and slt is the axial length of the gap. The linear actuator described. Before Kite Isu unit is composed of a narrow portion which is connected to the wide portion and the wide portion which is formed across the gap, the axial length of the surface facing the permanent magnet of the wide portion 2. The linear actuator according to claim 1, wherein ht is 0.40 strk or more and 1.14 strk or less when the length of the moving stroke in the axial direction is strk. Before Kite Isu unit consists wide portion and the narrow portion which is connected to the wide portion and which is formed across the gap, hg the spacing of the surface between which facing the permanent magnet of the pair of the auxiliary yoke, When the length of the gap in the axial direction is slt and the length of the surface of the wide portion facing the permanent magnet is ht, hg is 0.85 (slt + 2ht) or more and 1.19 (slt + 2ht) The linear actuator according to claim 1 , wherein: Before Kite Isu unit consists of a wide portion which is formed across the gap between the wide portion and connecting the narrow portion, the axial length of the permanent magnet hm, the axial direction of the gap Where hm is the length of the surface of the wide portion facing the permanent magnet, ht is the length in the axial direction, and hg is the distance between the surfaces of the pair of auxiliary yokes facing the permanent magnet. The linear actuator according to claim 1 , wherein: = slt + ht and hg = slt + 2ht. Linear actuator according to any one of claims 1 to 11, characterized in that the movable element by connecting the yoke of the permanent magnet and the other side. Linear actuator according to claim 12, the yoke of the other hand to the outer yokes, characterized in that the yoke of the hand and the inner yoke.

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