JP5439749B2 - Linear actuator - Google Patents

Description

  The present invention relates to a linear actuator that reciprocates a mover.

Conventionally, linear actuators that reciprocate a mover by electromagnetic action have been used. Among these linear actuators, there are known ones including a yoke formed in an annular shape, a shaft portion supported so as to reciprocate in the yoke, and a plunger provided in the shaft portion. (For example, refer to Patent Document 1). A permanent magnet and a coil are provided in the yoke.
Under such a configuration, when the coil is energized, the magnetic flux generated from the coil passes through the plunger along the length direction of the shaft from the yoke, thereby forming a magnetic flux loop from the yoke to the plunger. Therefore, the shaft portion reciprocates in the axial direction.

As another linear actuator, an electromagnet such as a solenoid that attracts the shaft portion by the attraction force of the electromagnet is also known.
Japanese Utility Model Publication No. 57-52787

  However, the linear actuator described in Patent Document 1 as described above has a problem that magnetic flux generated from a coil or the like leaks, and a large amount of energy is required to properly reciprocate the shaft portion. . That is, since the magnitude of the generated force is small and the thrust decreases with the change in the position of the magnetic pole, a small and large thrust cannot be realized. Although a permanent magnet can be incorporated in the magnetic circuit to change the direction of coil energization and change the direction of thrust generation, the thrust drop at the stroke end is large, so there is no thrust drop when trying to use a relatively large thrust Therefore, the effective stroke is shortened.

  On the other hand, in the solenoid type, although a large thrust can be obtained, it is necessary to provide a plurality of electromagnets or an elastic member such as a spring in order to return the moved shaft portion, which increases the size as a whole. is there.

  The present invention has been made in view of such circumstances, and with a simple configuration similar to that of a conventional reciprocating type linear actuator, the thrust generation efficiency is improved and effective thrust is generated over a wide range. An object of the present invention is to provide a linear actuator that can be used.

In order to solve the above problems, the present invention provides the following means .

The present invention includes a stator, a mover supported by the stator so as to reciprocate, a coil that generates a magnetic flux for reciprocating the mover, and either the stator or the mover. A permanent magnet arranged in such a manner that different magnetic poles are arranged along the reciprocating direction, and provided on the other of the stator or the movable element, projecting toward the permanent magnet, and the movable element is reciprocated. A projecting magnetic pole portion disposed so as to face the center between different magnetic poles in the permanent magnet, and the permanent magnet is provided by the magnetic flux of the coil and the permanent magnet. It is configured to generate a thrust for moving the mover between the stator or the mover and the protruding magnetic pole part, and at least of both ends of the protruding magnetic pole part in the reciprocating direction. The magnetic resistance at one end is gradually increased from the center in the reciprocating direction toward the edge of the one end, provided at either the stator or the mover, and the reciprocating A projecting wall portion projecting in a direction intersecting the reciprocating direction so as to overlap with the other of the stator or the movable element when viewed from the moving direction, and the generation of the thrust and the magnetic flux of the coil and the permanent magnet An attraction force generating portion that generates an attraction force for attracting the mover in the reciprocating direction is provided on both sides of the reciprocating drive direction with the protruding magnetic pole portion interposed therebetween.

According to the present invention, with a simple configuration similar to that of a conventional reciprocating type linear actuator, thrust for moving the mover is generated by the magnetic flux of the coil and the permanent magnet, and the mover is moved in the reciprocating direction. A suction force for suction can be generated.

Therefore, the mover can be reciprocated not only by thrust but also by suction force, and thrust generation efficiency can be improved.

At this time, the suction force generating portion is provided in either the stator or the mover, and the reciprocating direction is overlapped with the other of the stator or the mover as viewed from the reciprocating direction. Since the projecting wall portion projecting in the direction intersecting with is included, it is possible to reliably generate thrust and suction force for the mover.

Further, it is effective by gradually increasing the magnetoresistance of at least one end portion of the projecting magnetic pole portion in the reciprocating direction from the center portion toward the edge of the one end portion in the reciprocating direction. Since the path of the magnetic flux can be limited, the leakage magnetic flux between at least one end of the projecting magnetic pole portion and either the stator or the mover can be reduced.

Therefore, it is possible to further improve the thrust generation efficiency and increase the thrust on the mover over a wide range, and improve the stability of the reciprocating motion of the mover .

As described above, specific examples of “gradually increasing” include, for example, a taper shape, a round shape, and a step shape, but it goes without saying that other modes may be used. Absent.

  Further, the present invention is characterized in that a buffer member is provided between an inner wall of the protruding wall portion and a facing portion facing the inner wall of either the stator or the mover. To do.

  According to the present invention, not only noise and vibration due to contact between the moving element and the stator can be prevented, but also durability can be improved.

In addition, the present invention includes a suction force reinforcing portion that is provided at both ends of the reciprocating direction of either the stator or the mover and reinforces the suction force with respect to the mover by the suction force generation unit. It is characterized by.

In this invention, the attractive force with respect to the needle | mover is reinforced by the attractive force reinforcement part.
Thereby, the attraction | suction force with respect to a needle | mover can be increased and thrust generation efficiency can further be improved.

  Further, the present invention is characterized in that the attraction force reinforcing portion includes a magnetic body provided on at least one of the stator and the mover.

  According to this invention, the attractive force with respect to the needle | mover can be reinforced reliably.

  Further, in the present invention, the suction force reinforcing portion is provided in at least one of the stator and the mover, and is provided offset in a reciprocating region of the mover, and the reciprocating direction. Auxiliary protrusions extending along the line are provided.

  According to this invention, the suction force with respect to the needle | mover can be reliably reinforced by the auxiliary | assistant protrusion part.

  Further, the present invention is characterized in that at least one of the permanent magnet and the protruding magnetic pole portion is provided in a plurality in the reciprocating direction.

  According to this invention, the thrust with respect to a needle | mover can be increased and efficiency can further be improved.

  According to the present invention, since the magnetic flux density of the protruding magnetic pole portion can be increased by the magnetic resistance, the thrust generation efficiency is improved by a simple configuration similar to that of the conventional reciprocating linear actuator, and effective thrust can be obtained over a wide range. Can be generated.

(Embodiment 1)
Hereinafter, a linear actuator according to a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a linear actuator as a first embodiment of the present invention.
As shown in FIG. 1A, the linear actuator 100 includes a stator 101 formed in a cylindrical shape and a mover 105 formed in a cylindrical shape. The stator 101 and the mover 105 are made of a magnetic member.

The mover 105 is inserted through the cylindrical hole 101 a of the stator 101. The movable element 105 is supported so as to reciprocate in the direction of the axis L in the cylindrical hole of the stator 101 via a bearing member (not shown) such as a sliding bearing or a rolling bearing. A cylindrical permanent magnet 110 is provided at the center of the mover 105 in the direction of the axis L. That is, the mover 105 includes cylindrical half movers 105a and 105b, and a permanent magnet 110 is provided between the half movers 105a and 105b. Half body mover 105a, 105b and permanent magnet 110 are connected on the concentric axis.
The magnetic pole of the permanent magnet 110 is directed in the direction of the axis L, and one end side of the stator 101 in the axis L direction is an S pole and the other end side is an N pole. That is, the permanent magnet 110 is arranged such that different magnetic poles are arranged along the axis L direction which is the reciprocating direction.

The inner wall of the stator 101 is formed with recesses 109a and 109b that sag radially outward over the entire circumference. Coils 11a and 11b are provided in the recesses 109a and 109b, respectively. In addition, a projecting magnetic pole portion 102 that projects inward in the radial direction is provided between the recesses 109a and 109b in the direction of the axis L. That is, the projecting magnetic pole portion 102 protrudes toward the permanent magnet 110, when the armature 105 is at the center position of the reciprocating, are arranged so as to face the center between definitive different magnetic poles in the permanent magnet 110.
The tip surface 106 of the protruding magnetic pole portion 102 is a flat surface along the axis L. The tip surface 106 is formed at the center of the protruding magnetic pole portion 102 in the axis L direction. Further, stepped portions (magnetic resistance increasing portions) 107 a and 107 b that are sunk radially outward with respect to the permanent magnet 110 are formed at both ends of the protruding magnetic pole portion 102 in the axis L direction. That is, the protruding magnetic pole portion 102 is formed in a convex shape with respect to the permanent magnet 110. Therefore, the gap between the stepped portions 107a, 107b and the permanent magnet 110 (between the stepped portions 107a, 107b and the permanent magnet 110) when the stepped portions 107a, 107b face each other is a gap between the tip surface 106 of the protruding magnetic pole portion 102 and the permanent magnet 110. Is larger than the gap between the two (the tip surface 106 and the permanent magnet 110). Thereby, the magnetic resistance of the stepped portions 107 a and 107 b is larger than the magnetic resistance of the tip surface 106 of the protruding magnetic pole portion 102.

Further, inward ends of the stator 101 in the axis L direction are provided with inward flanges (protruding wall portions, suction force generating portions) 103a and 103b extending inward in the radial direction (a direction orthogonal to the axis L direction), respectively. It has been.
The inward flanges 103a and 103b are formed in a disc shape, and are arranged to face each other in parallel. Inner edge portions 112a and 112b of the inward flanges 103a and 103b extend radially inward from outer edge portions 113a and 113b of both end surfaces of the mover 105 in the axis L direction. That is, when the mover 105 reciprocates, both end surfaces of the mover 105 come into contact with the inner surfaces of the inward flanges 103 a and 103 b, respectively, so that the mover 105 comes out of the stator 101. It is to be prevented. In other words, as shown in FIG. 1B, the inward flanges 103a and 103b protrude radially inward over the entire circumference so as to overlap the end face of the mover 105 when viewed from the direction of the axis L. .

  Next, the operation of the linear actuator 100 according to this embodiment configured as described above will be described. Here, one end side in the axis L direction of the linear actuator 100 is defined as the left end in FIG. 2, and the direction is defined as the −x direction on the basis of the position of the protruding magnetic pole portion 102. Further, the other end side is the right end in FIG. 2, and the direction is the x direction on the basis of the position of the protruding magnetic pole portion 102.

First, in a natural state in which the coils 11a and 11b are not energized, the mover 105 is fixed to either end of the stator 101 by the magnetic force of the permanent magnet 110.
Here, it is assumed that the mover 105 is fixed to the other end side.
That is, as shown in FIG. 2, the magnetic flux from the permanent magnet 110 passes through the other half-body movable element 105a from the N pole and reaches the inner edge 112a of the inward flange 103a from the outer edge 113a. Further, it returns from the inward flange 103a to the south pole of the permanent magnet 110 through the protruding magnetic pole portion 102 and within one half movable element 105b. As a result, a magnetic flux loop M1 that exits from the N pole of the permanent magnet 110 and returns to the S pole is formed.

At this time, a magnetic pole is formed between the end face of the half body movable element 105a and the inner surface of the inward flange 103a by the magnetic flux passing through the end face of the half body movable element 105a and the inner surface of the inward flange 103a on the other end side. Is done. Therefore, a suction force that attracts the half-body movable element 105a and the inward flange 103a to each other is generated, and an F force directed to the other end side is applied to the movable element 105. The force in the x direction is F, and the force in the -x direction is -F.
Therefore, the outer edge portion 113a is sucked in the direction of the axis L so as to approach the inner edge portion 112a, the mover 105 moves in the x direction, and further on the other end side with the end face of the half body mover 105a. The inner surface of the orientation flange 103a contacts and is fixed in this state. At this time, the tip surface 106 of the protruding magnetic pole portion 102 is in a state of facing the permanent magnet 110 and the one half body movable element 105b.

Here, when the stepped portions 107a and 107b are not formed on the protruding magnetic pole portion 102, as shown in FIG. 8, a part of the magnetic flux from the N pole of the permanent magnet 110 ′ is the other end of the protruding magnetic pole portion 102 ′. It leaks out through the end portion 102a 'on the side. That is, since the gap between the end portion of the projecting magnetic pole portion 102 ′ and the half-body movable element 105a ′ is small and the magnetic resistance is small, the leakage magnetic flux m1 ′ is generated. Therefore, the magnetic flux density of the attractive force generating surface is reduced at the magnetic pole between the end face of the half body movable element 105a ′ and the inner surface of the inward flange 103′a. As a result, the attractive force is reduced.
In this embodiment, as shown in FIG. 9, a stepped portion 107a is formed in the protruding magnetic pole portion 102, the gap between the end portion of the protruding magnetic pole portion 102 and the half-body movable element 105a is large, and the magnetic resistance is large. Therefore, the leakage magnetic flux m1 from the N pole of the permanent magnet 110 is extremely small. Therefore, the magnetic flux density of the attractive force generation surface increases at the magnetic pole between the end face of the half body movable element 105a and the inner surface of the inward flange 103a, and as a result, the attractive force increases. Thereby, the mover 105 is firmly fixed to the other end side of the stator 101.

  When a current in a predetermined direction is passed through the coils 11a and 11b with the mover 105 fixed to the other end of the stator 101, magnetic flux is generated from the coils 11a and 11b. As shown in FIG. 3, since the magnetic flux loop M1 is canceled by the magnetomotive force from the coil 11a, the magnetic flux from the coil 11b and the magnetic flux from the N pole of the permanent magnet 110 are the other end of the half armature 105a. It progresses to the protruding magnetic pole part 102 through the step part 107a without going to the side. Further, the magnetic flux passes through the stator 101 from the protruding electrode portion 102, and returns from the inner surface of the inward flange 103b to the south pole of the permanent magnet 110 through the half-body movable element 105b. Thereby, the magnetic flux loop M2 is formed. At this time, a magnetic flux passes from the mover 105 to the projecting magnetic pole portion 102, whereby a magnetic pole is formed between the mover 105 and the projecting magnetic pole portion 102. A force (thrust) of -F in the direction of the parallel axis L is generated. Therefore, the mover 105 moves in the −x direction.

Here, when the stepped portions 107a and 107b are not formed on the protruding magnetic pole portion 102, the magnetic flux that has reached the protruding magnetic pole portion through the inward flange on the other end side from the mover is the end portion on one end side of the protruding magnetic pole portion. (The reference numeral 102b ′ shown in FIG. 8) leaks to the half body movable element (reference numeral 105b ′ shown in FIG. 8).
In the present embodiment, since the stepped portion 107b is formed, the leakage of magnetic flux to the half-body movable element 105b becomes extremely small, and the thrust to the movable element 105 increases.

Conventionally, the mover is moved only by thrust, but in the linear actuator 100 according to the present embodiment, a suction force is applied to the thrust.
That is, when the magnetic flux from the coil 11b and the magnetic flux from the permanent magnet 110 reach the end face of the half body movable element 105b from the inner surface of the inward flange 103b, the inner surface of the inward flange 103b and the half body movable element 105b A magnetic pole is formed between the end face and an attractive force between the mover 105 and the inward flange 103b. At this time, since the leakage magnetic flux from the stepped portion 107b to the half movable element 105b is extremely small, the attractive force between the inner surface of the inward flange 103b and the end face of the half movable element 105b also increases.
As a result, a suction force of −F is applied to the mover 105. Therefore, an attractive force is added to the thrust generated by the magnetic pole between the protruding magnetic pole portion 102 and the movable element 105, and the movable element 105 moves in the −x direction by the thrust and the attractive force.

  Therefore, as shown in FIG. 4, the mover 105 is arranged at the center in the direction of the axis L with respect to the stator 101 at a certain timing. As described above, when the mover 105 passes near the center of the stator 101, the magnetic flux from the coil 11b and the magnetic flux from the N pole of the permanent magnet 110 do not pass through the stepped portion 107a having a high magnetic resistance, but the front end face 106. It will pass through the other end side. Therefore, the magnetic flux density between the protruding electrode portion 102 and the mover 105 is increased, and the thrust is increased.

As the mover 105 continues to move in the −x direction, the inner surface of the inward flange 103b and the end face of the half-body mover 105b come into contact with each other as shown in FIG. 5, and the movement of the mover 105 is restricted. . Since the suction force depends on the distance between the inner surface of the inward flange 103b and the end surface of the half-body movable element 105b, the suction force is maximized in this state.
At this time, even if the energization is stopped, as shown in FIG. 6, the magnetic flux from the N pole of the permanent magnet 110 passes through the half-body movable element 105a, and the protruding electrode portion 102, the inward flange 103b, the half-body movable element. The magnetic flux loop M3 is formed by passing through 105b and returning to the S pole. Therefore, the mover 105 is fixed on one end side by the attractive force generated by the magnetic pole between the inner surface of the inward flange 103b and the end face of the half-body mover 105b.

Furthermore, when a reverse current is passed through the coils 11a and 11b, as shown in FIG. 7, the magnetic flux from the permanent magnet 110 and the magnetic flux from the coil 11a are inward from the end face a of the half-body movable portion 105a. A magnetic flux loop M4 is formed by passing through the flange 103a, the protruding electrode portion 102, the stepped portion 107b, and the half body movable element 105b. As a result, F thrust and suction force are applied to the mover 105, and the mover 105 moves in the x direction.
These are repeated and the mover 105 reciprocates.

  FIG. 10 is a graph showing the relationship between the position of the mover 105 and the generated force applied to the mover 105. The generated force F is obtained by adding a suction force to a thrust. This graph shows the characteristics of four states which are divided by the state of energization / non-energization of the coils 11a and 11b and the state of presence or absence of the stepped portions 107a and 107b. The position x indicates the other end of the stator 101, the position −x indicates one end of the stator 101, and the position 0 indicates the center of the stator 101.

A characteristic a indicates a characteristic of the generated force when there is no stepped portion 107a, 107b and is not energized. A characteristic b is a case where there are the stepped portions 107a and 107b, and shows a characteristic of the generated force when no power is supplied. That is, the characteristics a and b indicate the suction force.
As shown by the characteristics a and b, when the movable element 105 is disposed at the end of the stator 101, the suction force is maximized. Furthermore, at the both ends of the stator 101, the suction force when the step portions 107a and 107b are present is almost double the suction force when there is no step portion 107a and 107b. That is, the attractive force is increased by reducing the leakage magnetic flux and increasing the magnetic flux density.

A characteristic c indicates a characteristic of the generated force at the time of energization when there is no stepped portion 107a, 107b. The characteristic b is a case where there are the stepped portions 107a and 107b, and shows the characteristic of the generated force when energized. That is, the characteristics a and b indicate thrust + attraction force.
As shown by the characteristics c and d, when the mover 105 is arranged before and after the center of the stator 101, the generated force in the case where the stepped portions 107a and 107b are present increases. That is, the magnetic flux from the coil 11b (11a) and the magnetic flux from the N pole of the permanent magnet 110 are not passed through the stepped portion 7a (7b) but concentrated on the tip surface 106 of the protruding magnetic pole portion 102, so that the magnetic flux density is increased. The thrust is increased, and thus the generated force is increased.

As described above, according to the linear actuator 100 in this embodiment, the magnetic flux density between the projecting magnetic pole portion and the mover can be increased by the stepped portions 7a and 7b, so that the thrust force on the mover 105 can be increased. it can. Therefore, it is possible to improve the thrust generation efficiency with a simple configuration and generate an effective thrust over a wide range.
Moreover, since the attraction | suction force can also be generated using the energy for generating a thrust, the needle | mover 105 can be reciprocated appropriately with little energy.
In other words, since a reduction in thrust at the stroke end of the mover 105 can be compensated by the suction force, a large thrust can be generated over the entire stroke of the mover 105. Further, the thrust generation direction can be easily changed depending on the energization direction to the coils 11a and 11b. This is due to the fact that the central pole of the electromagnet is the N pole and the S pole, and that the opposing magnetic pole (projecting magnetic pole portion 102) has a convex shape.
Furthermore, at the stroke end of the mover 105, an attractive force is generated by the magnetic flux of the permanent magnet 110, so that the position at the stroke end of the mover 105 can be maintained even when the energization of the coils 11a and 11b is stopped (at zero current). It becomes. This force is further increased by energization.

Here, in automobiles and the like, the replacement of hydraulic actuators with electric actuators and the like has been studied, but naturally there is a demand for a small actuator that generates a large thrust. If the magnetic circuit is configured like the linear actuator 100 according to the present embodiment, a small and large thrust actuator can be provided. In a lock mechanism or the like, it is necessary to hold the state in which the mover 105 is moved in one direction. According to the linear actuator 100, the position can be held even without energization, and the holding force is to be increased. Can increase the current applied to the coils 11a and 11b, and the lock mechanism can be realized with low power consumption.
Further, opening and closing of the compressor and the valve often requires a large thrust at the stroke end of the mover 105, and a large thrust can be generated at the stroke end of the mover 105 like the linear actuator 100. By applying the actuator, it can greatly contribute to the efficiency improvement and miniaturization of these devices.

(Embodiment 2)
Next, a second embodiment of the present invention will be described.
FIG. 11 shows a second embodiment of the present invention.
In FIG. 11, the same components as those shown in FIGS. 1 to 9 are denoted by the same reference numerals, and the description thereof is omitted.
This embodiment and the first embodiment have the same basic configuration, and different points will be mainly described here.

In the present embodiment, tapers (magnet resistance increasing portions) 115a and 115b are formed at both ends of the protruding magnetic pole portion 102 in the axis L direction. The tapers 115a and 115b are formed so as to gradually become thinner toward both ends in the direction of the axis L. That is, the taper 115a, 115b is formed so that the distance dimension between the protruding magnetic pole portion 102 and the mover 105 gradually increases as it goes to both ends in the axis L direction. In other words, the magnetic resistance in the tapers 115a and 115b changes so as to gradually increase from the central portion (tip surface 106) side of the projecting magnetic pole portion 102 to the end surface side of the projecting magnetic pole portion 102. Not only can the same effect as that of the first embodiment be achieved, but also the thrust and suction force with respect to the movable element 105 can be changed smoothly according to the reciprocating movement of the movable element 105, and the reciprocating movement of the movable element 105 can be improved. Stability can be improved. Further, it is possible to prevent the step from being caught at the time of assembling, and the assembling workability can be improved.

The magnetic resistance increasing portion provided in the protruding magnetic pole portion 102 can be changed as appropriate.
For example, as shown in FIG. 12, step portions 107a and 107b and tapers 115a and 115b may be provided together.
Further, as shown in FIG. 35, the magnetic resistance increasing portion may be formed in a round shape. That is, the rounded surface may be circular, or the magnetic resistance may be gradually changed by gradually changing the curvature of the rounded surface as shown in FIG. Note that the protruding magnetic pole portion 102 in the figure has a gradually decreasing curvature from the central portion toward the end portion. Furthermore, it is good also considering the center part of a round surface as a flat surface.
In addition, as shown in FIG. 36, a plurality of stepped portions 107a and 107b may be provided so that the magnetic resistance increasing portion may be formed stepwise from the central portion side to both ends of the protruding magnetic pole portion 102. This also makes it possible to gradually change the magnetic resistance from the central portion side to both ends of the protruding magnetic pole portion 102.
Furthermore, as shown in FIG. 37, spacers 114 made of resin or metal may be provided on the stepped portions 107a and 107b. The surface of the spacer 114 is preferably arranged flush with the tip surface 106. Thereby, the catch of a level | step difference can be prevented and an assembly workability | operativity can be improved. Needless to say, if the stepped portions 107a and 107b are formed, the processing can be facilitated rather than forming a taper shape or a round shape.

(Embodiment 3)
Next, a third embodiment of the present invention will be described.
FIG. 13 shows a second embodiment of the present invention.
In FIG. 13, the same components as those shown in FIGS. 1 to 12 are denoted by the same reference numerals, and description thereof is omitted.
This embodiment and the first embodiment have the same basic configuration, and different points will be mainly described here.

  The linear actuator 1 in the present embodiment includes a stator 2 formed in a cylindrical shape and a mover 3 extending in a long shape. The stator 2 and the mover 3 are made of magnetic members.

The stator 2 includes a pair of annular bodies 7a and 7b formed with recesses 6a and 6b, respectively. That is, the cross-sections of the annular bodies 7a and 7b are formed in a U shape, and the recesses 6a and 6b are opened inward in the radial direction. The pair of annular bodies 7 a and 7 b are connected via an annular permanent magnet 8. And a pair of annular bodies 7a and 7b and the permanent magnet 8 are arrange | positioned coaxially.
The magnetic pole of the permanent magnet 8 is directed in the direction of the axis L, and one end side of the stator 2 in the axis L direction is an N pole and the other end side is an S pole.

The mover 3 is inserted into the cylindrical hole 2 a of the stator 2. The mover 3 is supported so as to reciprocate in the direction of the axis L in the cylindrical hole of the stator 2 via a bearing member (not shown) such as a sliding bearing or a rolling bearing.
The mover 3 includes a shaft portion 9 extending in a columnar shape. At both ends in the longitudinal direction of the shaft portion 9, flanges (protruding wall portions, suction force generating portions) 12 a and 12 b extending in a direction perpendicular to the axis L direction are provided. The flanges 12a and 12b are formed in a disk shape, and are arranged to face each other in parallel. The outer edge portions 16 a and 16 b of the flanges 12 a and 12 b extend radially outward from the inner edge portions 17 a and 17 b on both end surfaces of the stator 2. That is, the inner walls of the outer edge portions 16a and 16b of the flanges 12a and 12b come into contact with the inner edge portions 17a and 17b of the stator 2 when the mover 3 reciprocates, whereby the mover 3 Is prevented from coming out of the stator 2. In other words, as shown in FIG. 13B, the flanges 12 a and 12 b protrude in a direction orthogonal to the axis L direction over the entire circumference so as to overlap the end surface of the stator 2 when viewed from the axis L direction. ing.

A projecting magnetic pole portion 13 extending outward in the radial direction is provided over the entire circumference of the central portion in the longitudinal direction (axis L direction) of the mover 3. The protruding magnetic pole portion 13 has a convex cross section. The leading end surface 14 of the projecting magnetic pole portion 13 is disposed to face the permanent magnet 8 and the leading end surfaces of the projecting portions of the annular bodies 7a and 7b that sandwich the permanent magnet 8.
Further, step portions (magnetic resistance increasing portions) 15 a and 15 b are formed at both ends of the protruding magnetic pole portion 13 in the axis L direction.

With this configuration, when the coils 11a and 11b are energized, the mover 3 reciprocates in the same manner as described above.
As described above, according to the linear actuator 1 in the present embodiment, not only can the same effect as described above be achieved, but also the permanent magnet 8 is provided on the stator 2 side, so that the weight and size of the mover 3 can be reduced. Can be planned.

(Embodiment 4)
Next, a fourth embodiment of the present invention will be described.
FIG. 14 shows a fourth embodiment of the present invention.
In FIG. 14, the same components as those shown in FIGS. 1 to 13 are denoted by the same reference numerals, and the description thereof is omitted.
The basic configuration of this embodiment is the same as that of the third embodiment, and here, different points will be mainly described.

In the present embodiment, elastic members (buffer members) 20 such as urethane and rubber are provided on the inner walls of the flanges 12a and 12b. That is, the elastic member 20 is provided between the inner wall parts of the flanges 12a and 12b and the opposing part (end surface of the stator 2) facing these inner wall parts.
Under such a configuration, when the mover 3 is arranged at the end of the stator 2, the inner edge portions 17 a and 17 b are not directly in contact with the inner wall portions of the flanges 12 a and 12 b, respectively. Contact.
Therefore, not only can the noise and vibration due to the contact between the mover 3 and the stator 2 be prevented, but also the durability can be improved.
The elastic member 20 is provided on the inner wall portions of the flanges 12a and 12b. However, the elastic member 20 is not limited to this, and may be provided on the inner edge portions 17a and 17b, and the inner wall portions and inner edge portions of the flanges 12a and 12b. You may provide in both 17a, 17b.

(Embodiment 5)
Next, a fifth embodiment of the present invention will be described.
FIG. 15 shows a fifth embodiment of the present invention.
In FIG. 15, the same components as those shown in FIGS. 1 to 14 are denoted by the same reference numerals, and the description thereof is omitted.
The basic configuration of this embodiment is the same as that of the third embodiment, and here, different points will be mainly described.

In the present embodiment, auxiliary magnets (magnetic body, attractive force reinforcing portions) 21a, 21b made of annular permanent magnets are provided on the inner edge portions 17a, 17b. The magnetic poles of the auxiliary magnets 21 a and 21 b are oriented in the same direction as the permanent magnet 8.
Under such a configuration, when a magnetic pole is formed between the outer edge portions 16a and 16b and the inner edge portions 17a and 17b by energization of the coils 11a and 11b, the magnetic flux of the coils 11a and 11b and the permanent magnet 8 The magnetic fluxes of the auxiliary magnets 21a and 21b are added to the magnetic flux.
Thereby, the attractive force with respect to the needle | mover 3 can be increased, and thrust generation efficiency can further be improved.

(Embodiment 6)
Next, a sixth embodiment of the present invention will be described.
FIG. 16 shows a sixth embodiment of the present invention.
In FIG. 16, the same components as those shown in FIGS. 1 to 15 are denoted by the same reference numerals, and description thereof is omitted.
The basic configuration of this embodiment is the same as that of the third embodiment, and here, different points will be mainly described.

In the present embodiment, auxiliary protrusions (suction force reinforcing portions) 24a and 24b are provided on the inner edges of the inner walls of the flanges 12a and 12b. The auxiliary protrusions 24a and 24b extend in a rectangular shape (step shape) toward the inside in the direction of the axis L. The distance dimension in the direction of the axis L between the apex parts 25a and 25b of these auxiliary protrusions 24a and 24b is set equal to the length dimension of the stator 2 in the longitudinal direction. The auxiliary protrusions 24 a and 24 b are provided offset to the reciprocating region S of the mover 3. Therefore, in the reciprocating motion of the mover 3, the mover 3 does not contact the auxiliary protrusions 24a and 24b.
The reciprocating region S is a region where the outer edge portions 16a and 16b reciprocate with respect to the inner edge portions 17a and 17b. That is, the reciprocating region S refers to the entire region in which the outer edge portions 16a and 16b and the inner edge portions 17a and 17 overlap in the radial direction and extend along the axis L direction.

Under such a configuration, even when the outer edge portions 16a and 16b are separated from the inner edge portions 17a and 17b, the apex portions 25a and 25b of the auxiliary protruding portions 24a and 24b are brought close to the inner edge portions 17a and 17b. (The gap is reduced and the magnetic resistance is reduced), so that the magnetic flux easily passes between the auxiliary projecting portions 24a and 24b and the inner edge portions 17a and 17b, and the apex portions 25a and 25b and the inner edge portion 17a. , 17b are also formed with magnetic poles. Therefore, the attractive force due to the magnetic pole formed between the apex portions 25a, 25b and the inner edge portions 17a, 17b is added to the attractive force due to the magnetic pole formed between the outer edge portions 16a, 16b and the inner edge portions 17a, 17b. It is done.
Therefore, the suction force with respect to the needle | mover 3 can be increased, and thrust generation efficiency can further be improved.
In addition, the generating force at the time of electricity supply increases by providing auxiliary protrusion part 24a, 24b. That is, since the generated force at the time of current switching is large, it is suitable for applications that require faster response.
Further, for example, when the mover 3 is arranged at the other end of the stator 2, the inner edge when the coils 11a and 11b are energized by appropriately providing the step portion 24b closer to the inner edge portion 17b. The magnetic flux between the portion 17b and the outer edge portion 16b can be more easily passed, and the attractive force can be further increased.

(Embodiment 7)
Next, a seventh embodiment of the present invention will be described.
FIG. 17 shows a seventh embodiment of the present invention.
In FIG. 17, the same components as those shown in FIGS. 1 to 16 are denoted by the same reference numerals, and description thereof is omitted.
The basic configuration of this embodiment is the same as that of the third embodiment, and here, different points will be mainly described.

  In the present embodiment, outward projecting portions (auxiliary projecting portions, suction force reinforcing portions) 27a and 27b that are directed outward in the axis L direction are provided at the radial center of both end faces of the stator 2. Yes. The cross sections of the outward projecting portions 27a and 27b are formed in a rectangular shape. The distance dimension in the axis L direction between the tip surfaces of the outward projecting portions 27a and 27b is set equal to the distance dimension in the axis L direction between the inner walls of the flanges 12a and 12b. Further, the outward projecting portions 27 a and 27 b are offset from the reciprocating region S of the mover 3. Therefore, in the reciprocating motion of the mover 3, the mover 3 does not contact the outward projecting portions 27a and 27b.

Under such a configuration, even in a state where the outer edge portions 16a and 16b and the inner edge portions 17a and 17 are separated from each other, the movable element 3 of the outward projecting portions 27a and 27b is formed in the same manner as in the fourth embodiment. A magnetic pole is formed between the apex portion on the side and the outer edge portions 16a and 16b. Therefore, a magnetic pole formed between the apex of the outward projecting portions 27a and 27b and the inner edge portions 17a and 17b is attracted by the magnetic pole formed between the outer edge portions 16a and 16b and the inner edge portions 17a and 17b. The suction force by is applied.
Therefore, the suction force with respect to the needle | mover 3 can be increased, and thrust generation efficiency can further be improved.

  In the fifth and sixth embodiments, the auxiliary protrusions 24a and 24b or the outward protrusions 27a and 27b are provided. However, the installation position and size of the auxiliary protrusions 24a and 24b depends on the required generating force of the mover 3. It can be appropriately changed depending on the installation space. In addition, the shapes of the auxiliary protrusions 24 a and 24 b and the outward protrusions 27 a and 27 b can be changed as appropriate according to the force generated by the mover 3. For example, as shown in FIGS. 18 and 19, the auxiliary protrusions 24a and 24b or the outward protrusions 27a and 27b may be provided with a taper that becomes thinner toward the base end side.

(Embodiment 8)
Next, an eighth embodiment of the present invention will be described.
20 to 23 show an eighth embodiment of the present invention.
20 to 23, the same components as those shown in FIGS. 1 to 19 are denoted by the same reference numerals, and the description thereof is omitted.
The basic configuration of this embodiment is the same as that of the third embodiment, and here, different points will be mainly described.

In the present embodiment, a plurality of permanent magnets 8 are provided in the direction of the axis L. The magnetic poles of the plurality of permanent magnets 8 are aligned in the same direction, with the N pole directed toward one end and the S pole directed toward the other end. That is, these permanent magnets 8 are arranged such that different magnetic poles are arranged along the axis L direction which is the reciprocating direction. In addition, annular magnetic members 28 a and 28 b are provided between the permanent magnets 8.
The shaft portion 9 is provided with a plurality of protruding magnetic pole portions 13a and 13b with a predetermined interval in the direction of the axis L. As shown in FIG. 22, the protruding magnetic pole portions 13 a and 13 b have both ends when the mover 3 is arranged at the center in the longitudinal direction of the stator 2, that is, when the mover 105 is at the center position of the reciprocating motion. so that the opposed to the center between the definitive different magnetic poles in the permanent magnet 8, respectively.

Under such a configuration, the movable element 3 is fixed to, for example, the other end side when the coils 11a and 11b are not energized. That is, as shown in FIG. 20, the magnetic flux from the N pole of the permanent magnet 8a on the other end side passes through the magnetic member 28a on the other end side, the protruding magnetic pole portion 13a, and the shaft portion 9 in order, and reaches the flange 12a. Then, the magnetic flux reaches the inner edge portion 17a from the outer edge portion 16a and returns to the S pole in the other annular body 7a, thereby forming the main magnetic flux loop M5. At this time, a magnetic force between the outer edge portion 16 a and the inner edge portion 17 a causes an attractive force of −F, and the mover 3 is fixed on the other end side of the stator 2.
The magnetic flux from the N pole of the permanent magnet 8b on one end side passes through the projecting magnetic pole portion 13b and the magnetic member 28b in this order from one annular body 7b and returns to the S pole. Thereby, the magnetic flux loop M6 is formed.

When a current is passed in a predetermined direction from this state, as shown in FIG. 21, the magnetic flux from the coil 11b goes to one end side of the stator 2 together with the magnetic flux from the N pole of the permanent magnet 8b, and from the inner edge portion 17b. It reaches the outer edge 16b of the flange 12b on one end side. Further, the magnetic flux passes through the shaft portion 9, the protruding magnetic pole portion 13b, and the magnetic member 28b in this order and returns to the S pole of the permanent magnet 8b, thereby forming a magnetic flux loop M7.
The magnetic flux from the coil 11a passes through the other annular body 7b (inner edge portion 17a), the flange 12a (outer edge portion 16a), the shaft portion 9 protruding magnetic pole portion 13a in this order, and further returns to the annular body 7b. Is formed.
Further, the magnetic flux from the N pole of the permanent magnet 8a passes through the magnetic member 28a, the protruding magnetic pole portion 13a, and the other annular body 7a in this order to return to the S pole, thereby forming a magnetic flux loop M8.
The projecting magnetic pole portions 13 a and 13 b form magnetic poles, respectively, and F thrust is generated on the mover 3. Further, an attractive force F is generated on the mover 3 by the magnetic pole between the outer edge portion 16b and the inner edge portion 17b on one end side. As a result, the mover 3 moves in the x direction.

  When the mover 3 further moves in the x direction, the mover 3 is arranged at the center in the longitudinal direction of the stator 2 as shown in FIG. Furthermore, as shown in FIG. 23, the outer edge part 16b contacts the inner edge part 17b, and the mover 3 is fixed on one end side.

  As described above, according to the present embodiment, since a plurality of magnetic poles are formed in the direction of the axis L of the stator 2 and the mover 3, the thrust on the mover 3 can be increased, and the thrust generation efficiency can be improved. Can do.

(Embodiment 9)
Next, a ninth embodiment of the present invention will be described.
24 to 27 show a ninth embodiment of the present invention.
24 to 27, the same components as those shown in FIGS. 1 to 23 are denoted by the same reference numerals, and the description thereof is omitted.
The basic configuration of this embodiment is the same as that of the third embodiment, and here, different points will be mainly described.

In the present embodiment, a plurality of permanent magnets 8 are provided in the direction of the axis L, and the magnetic poles of these permanent magnets 8 are oriented in a direction perpendicular to the direction of the axis L. Specifically, the N pole of the permanent magnet 8a-1 disposed on the other end side is directed to the radially outward side, and the S pole is directed to the radially inward side (mover 3 side). Yes. The N pole of the adjacent permanent magnet 8a-2 is directed radially inward, and the S pole is directed radially outward. The N pole of the adjacent permanent magnet 8b-1 is directed to the radially outward side, and the S pole is directed to the radially inward side. The N pole of the adjacent permanent magnet 8b-1 on the one end side thereof is directed to the radially inner side, and the S pole is directed to the radially outer side. That is, the permanent magnets 8 are arranged alternately in the direction of the axis L so that the magnetic poles of the adjacent permanent magnets 8 are different. In other words, these permanent magnets 8 are arranged such that different magnetic poles are arranged along the axis L direction which is the reciprocating direction.
The shaft portion 9 is provided with a plurality of protruding magnetic pole portions 13a and 13b. As shown in FIG. 26, each of the protruding magnetic pole portions 13 a and 13 b has two permanent magnets 8 a-1 and 8 a-2 on one end side when the mover 3 is arranged at the center in the longitudinal direction of the stator 2. In addition, the two permanent magnets 8b-1 and 8b-2 on the other end side are arranged to face each other. That is, the protruding magnetic pole portions 13a and 13b face the centers between different magnetic poles of the permanent magnets 8a-1 and 8a-2, respectively, when the movable element 105 is at the center position of the reciprocating motion.
The annular body 7 is integrally formed.

Under such a configuration, the movable element 3 is fixed to, for example, the other end side when the coils 11a and 11b are not energized. That is, as shown in FIG. 24, the magnetic flux from the north pole of the permanent magnet 8a-2 passes through the protruding magnetic pole portion 13a and the shaft portion 9, and reaches the flange 12a. Then, the magnetic flux reaches the inner edge portion 17a from the outer edge portion 16a and returns to the south pole of the permanent magnet 8a-2 on the other end side of the annular body 7, thereby forming a magnetic flux loop M11. At this time, a magnetic force between the outer edge portion 16 a and the inner edge portion 17 a causes an attractive force of −F, and the mover 3 is fixed on the other end side of the stator 2.
The magnetic flux from the N pole of the permanent magnet 8b-2 passes through the protruding magnetic pole portion 13b and the shaft portion 9, and reaches the flange 12a. And the magnetic flux reaches | attains the inner edge part 17a from the outer edge part 16a, and returns to the S pole of the permanent magnet 8b-2 in the annular body 7, Thereby, the magnetic flux loop M10 is formed.

When a current is passed from this state in a predetermined direction, the magnetic flux from the coil 11b goes to one end side of the stator 2 together with the magnetic flux from the N pole of the permanent magnet 8b-1, as shown in FIG. The outer edge 16b of the flange 12b on one end side is reached from 17b. Furthermore, the magnetic flux returns to the S pole of the permanent magnet 8b-1 through the shaft portion 9 and the protruding magnetic pole portion 13b, thereby forming a magnetic flux loop M12.
The magnetic flux from the coil 11b goes to one end side of the stator 2 together with the magnetic flux from the N pole of the permanent magnet 8a-1, and reaches the outer edge portion 16b of the flange 12b on one end side from the inner edge portion 17b. Furthermore, the magnetic flux returns to the S pole of the permanent magnet 8a-1 through the shaft portion 9 and the protruding magnetic pole portion 13b, thereby forming a magnetic flux loop M13.
Further, the magnetic flux from the coil 11a goes to the other end side of the stator 2 together with the magnetic flux from the N pole of the permanent magnet 8a-1, and reaches the outer edge portion 16a of the flange 12a on the other end side from the inner edge portion 17a. Further, the magnetic flux returns to the S pole of the permanent magnet 8a-1 through the shaft portion 9 and the protruding magnetic pole portion 13b, thereby forming a magnetic flux loop M14.
The projecting magnetic pole portions 13 a and 13 b form magnetic poles, respectively, and F thrust is generated on the mover 3. Further, the magnetic force between the outer edge portion 16b and the inner edge portion 17b generates an attractive force F for the mover 3. As a result, the mover 3 moves in the x direction.

  When the mover 3 further moves in the x direction, the mover 3 is arranged at the center in the longitudinal direction of the stator 2 as shown in FIG. Furthermore, as shown in FIG. 27, the outer edge portion 16b abuts on the inner edge portion 17b, and the mover 3 is fixed on one end side.

  As described above, according to the present embodiment, since a plurality of magnetic poles are formed in the direction of the axis L of the stator 2 and the mover 3, the thrust on the mover 3 can be increased, and the thrust generation efficiency can be improved. Can do.

(Embodiment 10)
Next, a tenth embodiment of the present invention will be described.
FIG. 28 shows a tenth embodiment of the present invention.
In FIG. 28, the same components as those shown in FIGS. 1 to 27 are denoted by the same reference numerals, and description thereof is omitted.
The basic configuration of this embodiment is the same as that of the third embodiment, and here, different points will be mainly described.

In the present embodiment, the length dimension in the axis L direction of the recesses 6a and 6b is larger than the length dimension in the axis L direction of the coils 11a and 11b. The coils 11a and 11b are eccentrically provided on the center side in the longitudinal direction of the recesses 6a and 6b, respectively. Then, flanges 12a and 12b are arranged in regions where the recesses 6a and 6b are vacant.
The shaft portion 9 is provided with a plurality of protruding magnetic pole portions 13a and 13b.

  Thereby, while the length dimension of the needle | mover 3 can be made small, thrust can be increased by several protrusion magnetic pole part 13a, 13b.

(Embodiment 11)
Next, an eleventh embodiment of the present invention will be described.
FIG. 33 shows an eleventh embodiment of the present invention.
In FIG. 33, the same components as those shown in FIGS. 1 to 32 are denoted by the same reference numerals, and the description thereof is omitted.
This embodiment and the first embodiment have the same basic configuration, and different points will be mainly described here.

The linear actuator 1a in this embodiment includes a rectangular parallelepiped and hollow case 59. Through holes 31 a and 31 b are respectively formed in the centers of both end surfaces in the longitudinal direction of the case 59. A shaft 32 extending in a columnar shape is inserted into the through holes 31a and 31b. Furthermore, bearings 33a and 33b for supporting the shaft 32 so as to be able to reciprocate are provided at the edges of the through holes 31a and 31b, respectively.
The shaft 32 is made of a metal such as iron. The shaft 32 may not be a metal. However, in the case of a cylindrical actuator, the inner diameter side having a smaller cross-sectional area is more likely to be magnetically saturated, and therefore, it is preferable in that saturation can be reduced by using the shaft 32 as a magnetic material.
The shaft 32 is provided with a cylindrical movable core (movable element) 36. That is, when the shaft 32 is press-fitted into the cylindrical hole 36 a of the movable core 36, the movable core 36 is fixed to the central portion in the longitudinal direction of the shaft 32.

  The movable core 36 is made of a magnetic member, and flanges 37a and 37b extending in a direction orthogonal to the axis L direction are provided on both end faces in the longitudinal direction. The flanges 37 a and 37 b are provided over the entire circumference of both end surfaces of the movable core 36. Further, on the surface side of the edge portions of the flanges 37a and 37b, tapers 38a and 38b are formed so as to become thinner outward in the radial direction.

A fixed core (stator) 41 is provided around the movable core 36. The fixed core 41 includes first annular bodies 40 a and 40 b that sandwich the permanent magnet 8. The first annular bodies 40a and 40b are formed in an L-shaped cross section, and their bottom surface portions are arranged to face each other. Second annular bodies 46a and 46b having an L-shaped cross section are provided at the ends in the axis L direction of the first annular bodies 40a and 40b. The bottom portions of the second annular bodies 46a and 46b are arranged to face each other. And the recessed parts 45a and 45b are formed by the inner surface of the 1st annular bodies 40a and 40b and the bottom face part of the 2nd annular bodies 46a and 46b.
Moreover, the vertical wall part orthogonal to the bottom face part of 2nd annular body 46a, 46b is provided with taper 50a, 50b which becomes thick as it goes to the front-end | tip of the axis line L direction.

Under such a configuration, the movable core 36 reciprocates and the shaft 32 reciprocates in the direction of the axis L in the same manner as described above.
Thereby, the suction force with respect to the movable core 36 can be increased reliably, and the thrust generation efficiency can be improved.
Further, since the tapers 38a, 38b, 50a, and 50b are formed, the gap (magnetic resistance) does not change rapidly, and therefore, a rapid change in magnetic flux can be prevented.

Embodiment 12
Next, a twelfth embodiment of the present invention will be described.
FIG. 34 shows a twelfth embodiment of the present invention.
34, the same components as those shown in FIGS. 1 to 33 are denoted by the same reference numerals, and the description thereof is omitted.
The basic configuration of this embodiment is the same as that of the eleventh embodiment, and only the differences will be described here.

The linear actuator 1b according to the present embodiment includes a rectangular parallelepiped and hollow case 59. The case 59 is made of a magnetic member. The case 59 includes a rectangular tubular case main body (stator) 60 made of a magnetic member.
Of the inner peripheral surface of the case main body 60, a projecting magnetic pole 60a projecting radially inward is provided at the center in the direction of the axis L. The protruding magnetic pole part 60a is formed in a rectangular cross section, and its tip is a flat surface. At both ends of the case body 60, convex lids 61a and 61b made of a magnetic member are provided.
The lid portions 61 a and 61 b are arranged facing each other outward in the direction of the axis L, and the bottom portions thereof are attached to the edges of the case main body portion 60. Concave portions 74a and 74b are provided at the centers of the bottom surface portions of the lid portions 61a and 61b, respectively. Further, through holes 67a and 67b are formed at the center of the lid portions 61a and 61b, and bearings 62a and 62b for supporting the shaft 32 so as to be able to reciprocate are provided in the through holes 67a and 67b. ing.

A cylindrical movable core (movable element) 69 and a permanent magnet 66 having the same shape are coaxially provided at the center in the longitudinal direction of the shaft 32, and the magnetization direction of the magnet is a direction along the axis L. It has become.
The movable core 69 is provided with convex convex half portions 63a and 63b that face each other outward in the direction of the axis L and are opposed to each other. The convex half portions 63a and 63b include cylindrical main body portions 75a and 75b and convex portions 76a and 76b provided at the center of one end surfaces of the main body portions 75a and 75b.
The bottom surface portions (the other end surfaces of the main body portions 75a and 75b) of the convex half portions 63a and 63b are arranged to face each other, and a permanent magnet 66 is provided between the bottom surface portions. That is, the bottom surfaces of the convex half parts 63 a and 63 b are joined to each other via the permanent magnet 66. The outer diameter of the convex half portions 63 a and 63 b is the same as the outer diameter of the permanent magnet 66. However, since the area of the suction force generating portion is determined by this diameter, it may be determined according to the required suction force.

The peripheral surfaces of the convex half portions 63a and 63b and the permanent magnet 66 are arranged to face the tip surface of the protruding magnetic pole portion 60a in a direction orthogonal to the axis L direction.
Moreover, half-body recessed parts 70a and 70b which are immersed in the radial direction inside are provided in the surrounding surface of main-body part 75a, 75b over the perimeter.
Furthermore, the convex portions 76a and 76b are disposed in the concave portions 74a and 74b, respectively. And the front end surface (suction force generation | occurrence | production part) of main-body part 75a, 75b and the bottom face part (suction force generation | occurrence | production part) of the inner edge part of cover part 61a, 61b are each arrange | positioned facing the axis L direction. . further,
The front end surfaces (suction force generating portions) of the convex portions 76a and 76b and the bottom surfaces (suction force generating portions) in the concave portions 74a and 74b are arranged to face each other in the direction of the axis L.
Further, tapers 71a and 71b are formed on the peripheral surfaces of the convex portions 76a and 76b so as to increase in thickness in the radial direction toward the tip. The convex portions 76a and 76b are provided in order to increase the generated thrust at the time of current switching, and there is no functional problem even if the convex portions 76a and 76b are not provided as shown in FIG. Further, the tapers 71a and 71b are provided to prevent a sudden change in magnetic flux and reduce leakage magnetic flux.

  Under such a configuration, when the coils 11a and 11b are energized, a magnetic pole is formed between the peripheral surfaces of the convex half portions 63a and 63b and the permanent magnet 66 and the tip surface of the protruding magnetic pole portion 60a. Thus, a thrust in the axis L direction acts on the shaft 32. Furthermore, a magnetic pole is formed between the front end surfaces of the main body portions 75a and 75b and the bottom surface portions of the inner edge portions of the lid portions 61a and 61b, whereby an attractive force in the direction of the axis L acts on the shaft 32. Furthermore, a magnetic pole is also formed between the front end surfaces of the convex portions 76a and 76b and the bottom surfaces in the concave portions 74a and 74b, whereby an attractive force in the direction of the axis L acts on the shaft 32.

As described above, according to the linear actuator 1b in the present embodiment, the suction force for sucking the shaft 32 can be generated not only on the front end surfaces of the main body portions 75a and 75b but also on the front end surfaces of the convex portions 76a and 76b. Therefore, the thrust generation efficiency can be further improved.
Moreover, since the half body recessed parts 70a and 70b are provided in the surrounding surface of the convex half-body parts 63a and 63b over the perimeter, and these half body recessed parts 70a and 70b work as a magnetic resistance, A magnetic flux loop can be formed efficiently without the magnetic flux between the permanent magnet 66 going outward in the direction of the axis L. Further, the half-body recesses 70a and 70b do not need to be provided, and can be provided to such an extent that magnetic saturation does not occur when considering the weight reduction of the movable part.
Further, since the permanent magnet 66 is provided on the shaft 32, the diameter of the permanent magnet 66 can be made smaller than that of the permanent magnet 8 in FIG. 28, so that the amount of the magnet used can be reduced and the cost can be further reduced. Can be reduced.

In addition, since the case main body 60 and the movable core 69 do not overlap in the direction of the axis L, the case 59 can be obtained simply by placing the movable core 69 in the case main body 60 and covering with the lid portions 61a and 61b. The movable core 69 can be easily and quickly incorporated therein.
In addition, since the case 59 is also used as a stator, a frame or the like is not necessary, so that the number of parts can be reduced and the configuration can be simplified.
Further, if the coils 11a and 11b and the movable core 69 are enlarged in the direction of the axis L, the performance can be improved, for example, the loss can be reduced while maintaining the height dimension H (shown in FIG. 34B). it can. Further, if the coils 11a and 11b are made larger in the direction of the axis L, their cross-sectional areas can be made constant and the height dimension H can be made smaller, so that the degree of freedom in design can be improved.

The technical scope of the present invention is not limited to the first to twelfth embodiments, and various modifications can be made without departing from the spirit of the present invention.
For example, as shown in FIG. 29, two permanent magnets 8 having magnetic poles oriented in a direction orthogonal to the direction of the axis L may be provided.
Further, as shown in FIG. 30, a recess 31 extending in the radial direction may be provided in the integrally formed annular body 7, and the permanent magnet 8 may be provided in the recess 31.
In addition, as shown in FIGS. 31A and 31B, the stator 2 and the movable element 3 may be formed in a rectangular shape. In this case, since the stator 2 can be formed by laminating silicon steel plates or the like in a direction orthogonal to the reciprocating direction of the mover 3 (N direction indicated by an arrow), loss can be suppressed.

Further, as shown in FIG. 32, the coils 11 a and 11 b may be provided on the shaft portion 9. However, it is preferable that the coils 11a and 11b are provided on the stator 2 side because there is no fear of disconnection due to movement.
Moreover, although the needle | mover 3 was supported by the bearing member, it is not restricted to this, You may make it support with elastic bodies, such as a coil spring and a leaf | plate spring.
Further, although the outer side is the stator 2 and the inner side is the movable element 3, the present invention is not limited to this, and the outer member may be the movable element and the inner member may be the stator.
Further, there may be no suction force generating portions such as the inward flanges 103a and 103b and the flanges 12a and 12b.
Needless to say, the first to twelfth embodiments and the modification examples can be freely combined.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows 1st Embodiment of the linear actuator which concerns on this invention, Comprising: (a) is a side view which shows a mode that the half of the stator was fractured | ruptured, (b) is the front view seen from the axis L direction It is. In the linear actuator of FIG. 1, it is explanatory drawing which shows the mode of the magnetic flux when not supplying with electricity to a coil. It is explanatory drawing which shows the mode of the magnetic flux when it supplies with electricity to the coil of FIG. 2 to one direction. It is explanatory drawing which shows a mode that the needle | mover of FIG. 3 was distribute | arranged to the center of the longitudinal direction of a stator. FIG. 5 is an explanatory diagram illustrating a state in which the stator of FIG. 4 is further moved in the −x direction and the inward flange and the mover are in contact with each other. In the linear actuator of FIG. 5, it is explanatory drawing which shows the mode of the magnetic flux when not energizing a coil. It is explanatory drawing which shows the mode of the magnetic flux when it supplies with electricity to the coil of FIG. 6 in the opposite direction. It is explanatory drawing which shows the mode of the magnetic flux when the level | step-difference part is not formed. In this embodiment, it is explanatory drawing which shows a mode that a leakage magnetic flux is reduced by the level | step-difference part. It is a graph which shows the relationship between the position of the needle | mover of FIG. 1, and the generated force added to a needle | mover. It is a figure which shows 2nd Embodiment of the linear actuator which concerns on this invention, Comprising: It is a side view which shows a mode that the half of the stator was fractured | ruptured. It is sectional drawing which shows the modification of the linear actuator of FIG. It is a figure which shows 3rd Embodiment of the linear actuator which concerns on this invention, Comprising: (a) is a side view which shows a mode that the half of the stator was fractured | ruptured, (b) is the front view seen from the axis L direction It is. It is a sectional side view which shows 4th Embodiment of the linear actuator which concerns on this invention. It is a sectional side view which shows 5th Embodiment of the linear actuator which concerns on this invention. It is a sectional side view which shows 6th Embodiment of the linear actuator which concerns on this invention. It is a sectional side view which shows 7th Embodiment of the linear actuator which concerns on this invention. It is a sectional side view which shows the modification of the linear actuator of FIG. FIG. 18 is a side sectional view showing another modification of the linear actuator of FIG. 17. It is a figure which shows 8th Embodiment of the linear actuator which concerns on this invention, Comprising: It is explanatory drawing which shows the mode of the magnetic flux when not energizing a coil. It is explanatory drawing which shows the mode of the magnetic flux when it supplies with electricity to the coil of FIG. 20 to one direction. It is explanatory drawing which shows a mode that the needle | mover of FIG. 21 was distribute | arranged to the center of the longitudinal direction of a stator. It is explanatory drawing which shows a mode that the stator of FIG. 22 moved to the x direction further, and the stator and the flange of the one end side contacted. It is a figure which shows 9th Embodiment of the linear actuator which concerns on this invention, Comprising: It is explanatory drawing which shows the mode of the magnetic flux when not energizing a coil. It is explanatory drawing which shows the mode of the magnetic flux when it supplies with electricity to one direction to the coil of FIG. It is explanatory drawing which shows a mode that the needle | mover of FIG. 25 was distribute | arranged to the center of the longitudinal direction of a stator. FIG. 27 is an explanatory diagram illustrating a state in which the stator of FIG. 26 is further moved in the x direction and the stator and the flange on one end side are in contact with each other. It is a sectional side view which shows 10th Embodiment of the linear actuator which concerns on this invention. It is a sectional side view which shows the 1st modification of the linear actuator which concerns on this invention. It is a sectional side view which shows the 2nd modification of the linear actuator which concerns on this invention. It is a figure which shows the 3rd modification of the linear actuator which concerns on this invention, Comprising: (a) is a sectional side view, (b) is the front view seen from the axis line L direction. It is a sectional side view which shows the 4th modification of the linear actuator which concerns on this invention. It is a figure which shows 11th Embodiment of the linear actuator which concerns on this invention, Comprising: (a) is sectional drawing which shows a mode that the linear actuator was seen from the side surface, (b) is the front view seen from the axis line L direction It is. It is a figure which shows 12th Embodiment of the linear actuator which concerns on this invention, Comprising: (a) is sectional drawing which shows a mode that the linear actuator was seen from the side surface, (b) is the front view seen from the axis L direction It is. It is sectional drawing which shows the 2nd modification of the linear actuator of FIG. It is sectional drawing which shows the 3rd modification of the linear actuator of FIG. It is sectional drawing which shows the 4th modification of the linear actuator of FIG.

1, 1a, 100 Linear actuator 2, 101 Stator 3, 105 Movable element 8, 66, 110 Permanent magnet 11a, 11b Coil 12a, 12b Flange (protruding wall part, attractive force generating part)
13 Protruding magnetic pole parts 15a, 15b Stepped part (Magnetic resistance increasing part)
20 Elastic member (buffer member)
21a, 21b Auxiliary magnet (magnetic body, attractive force reinforcement part)
24a, 24b Auxiliary protrusion (suction force reinforcement)
27a, 27b outward projection (auxiliary projection, suction force reinforcement)
36,69 Movable core (movable element)
41 Fixed core (stator)
60 Case body (stator)
60a Protruding magnetic pole part 102 Protruding magnetic pole parts 103a, 103b
Inward flange (projecting wall, suction force generator)
107a, 107b
Step part (Magnetic resistance increasing part)
115a, 115b
Taper (Magnetic resistance increasing part)

Claims (6)

A stator,
A mover supported by the stator so as to be capable of reciprocating;
A coil for generating magnetic flux for reciprocating the mover;
A permanent magnet provided on either the stator or the mover and arranged so that different magnetic poles are arranged along the reciprocating direction ;
The stator or provided on the other of the mover and protruded toward the permanent magnet when the armature is in the center position of the reciprocating so as to face the center between the different magnetic poles in said permanent magnet A projecting magnetic pole portion arranged,
The magnetic flux of the coil and the permanent magnet is configured to generate a thrust for moving the mover between the stator or the mover provided with the permanent magnet and the protruding magnetic pole part, and
The magnetic resistance of at least one end of both ends of the projecting magnetic pole in the reciprocating direction is gradually increased from the center in the reciprocating direction toward the edge of the one end.
A protruding wall provided on either the stator or the mover and protruding in a direction intersecting the reciprocating direction so as to overlap with the other of the stator or the mover when viewed from the reciprocating direction An attraction force generating portion that generates an attraction force that attracts the mover in the reciprocating direction by the magnetic flux of the coil and the permanent magnet along with the generation of the thrust, and the reciprocating drive direction across the protruding magnetic pole portion A linear actuator characterized by being provided on both sides . An inner wall of the projecting wall portion, between the stator and facing portion that faces the inner wall one of one of the movable element, according to claim 1, characterized in that cushioning member is provided Linear actuator. The suction force reinforcement part which reinforces the suction power with respect to the mover by the suction force generation part provided at both ends of the reciprocating direction in either the stator or the mover. The linear actuator according to claim 1 or 2 . The suction force reinforcing portion is
The linear actuator according to claim 3 , comprising a magnetic body provided on at least one of the stator and the mover. The suction force reinforcing portion is
It is provided on at least one of the stator and the mover, and is provided with an auxiliary protrusion provided offset in a reciprocating region of the mover and extending along the reciprocating direction. The linear actuator according to claim 3 or 4 , wherein: Wherein at least one of the permanent magnets or the salient-pole portion, the linear actuator according to any one of claims 1 to 5, characterized in that is provided with a plurality in the reciprocating direction.

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