JP2006158135A - Linear actuator and valve device using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a linear actuator that can obtain a large thrust force even when miniaturized and that is suitable for mass production, and a valve device. <P>SOLUTION: In the linear actuator 1 used for a valve device 100, a fixed body 3 is provided with a coil 33, and a fixed body side yoke 35 that surrounds the coil 33 from the outer peripheral surface to both sides in the axial direction of the coil 33 and whose ends 36a, 36b face each other in the axial direction via a slit 37 at the inner peripheral side of the coil 33. A movable body 5 is provided with a first movable body side yoke 51, a pair of magnets 53a, 53b stacked at both sides in its axial direction, and second movable body side yokes 55a, 55b at the end surfaces at the sides opposite to the first movable body side yoke 51. The magnets 53a, 53b are magnetized in the axial direction with same poles facing the first movable body side yoke 51. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a linear actuator and a valve device using the linear actuator.

  Conventionally, linear actuators used for valve devices in pumps, etc., use solenoids without using magnets, but this type of thrust is more thrust than volume reduction as miniaturization progresses. There is a problem of sudden decrease. In addition, for a short time, the thrust can be increased by supplying a large amount of current to the coil. However, continuous operation with a large amount of current applied to the coil is extremely dangerous and dangerous.

In view of this, there has been proposed one in which a movable body provided with one magnet inside an annular coil is arranged (see, for example, Patent Document 1).
JP 2002-206484 A

  However, the linear actuator using one magnet has the following problems, for example. First, when one magnet is magnetized in the axial direction, the use efficiency of magnetic flux decreases as the size is reduced, and there is a problem that a large thrust cannot be obtained. Further, if one magnet is magnetized in the radial direction, a magnetic flux is generated in the radial direction, so that a relatively large thrust can be obtained, but the radial magnetization itself is difficult. In particular, when the magnet is downsized, depending on the shape of the magnet, for example, in the case of a magnet having a small outer diameter dimension and a long linear dimension, it may be magnetized in the radial direction. It is extremely difficult, and the mass production is difficult because the magnetizing device itself may not be configured.

  In view of the above problems, an object of the present invention is to provide a linear actuator suitable for mass production and a valve device including the linear actuator, which can obtain a large thrust even when downsized. .

  In order to solve the above-described problem, in the linear actuator according to the present invention, a fixed body including a coil wound in an annular shape, and a first movable body whose peripheral surfaces face each other inside or outside the coil. A body-side yoke, and a movable body having a pair of magnets laminated on both sides in the axial direction with respect to the first movable body-side yoke, with the same pole facing the first movable body-side yoke, The movable body is driven in the axial direction by energizing the coil.

  In the present invention, each of the pair of magnets in the movable body has the same polarity and a magnetic repulsive force is acting. However, since the first movable body side yoke is disposed between the magnets, The magnet can be fixed with the same pole facing. In addition, since the pair of magnets in the movable body have the same polarity directed to the first movable body side yoke, a strong magnetic flux is generated in the radial direction from the first movable body side yoke. Therefore, if the first movable body side yoke and the peripheral surfaces of the coils are opposed to each other, a large thrust can be applied to the movable body. In addition, since the magnet only needs to be magnetized in the axial direction, unlike the case where the magnet is magnetized in the radial direction, the magnet can be easily magnetized even if it is downsized, and is suitable for mass production.

  In this invention, it is preferable that the said fixed body is arrange | positioned inside the said coil, and the outer peripheral surface of the said 1st movable body side yoke is facing the inner peripheral surface of the said coil. If comprised in this way, it will be easy to close a magnetic path compared with the structure which has arrange | positioned the magnet to the outer peripheral side of a coil. Further, when the magnet is arranged inside the coil, the magnet may be smaller than the case where the magnet is arranged outside the coil, so that the linear actuator can be configured at low cost.

  In the present invention, the fixed body wraps around both sides in the axial direction of the coil from the outer peripheral surface of the coil, and one front end portion and the other front end portion of the outer peripheral surface of the first movable body side yoke and the coil The fixed body side yoke is located in a gap with the inner peripheral surface, and the tip end portion of the fixed body side yoke is opposed in the axial direction through a slit, and there is a gap between the fixed body side yoke and the movable body. Is preferably ensured. It is preferable. If comprised in this way, a magnetic path can be closed.

  In the present invention, the fixed body side yoke is preferably formed with a coil wire lead-out portion for pulling out a terminal of the coil wire from the coil on at least one end face in the axial direction.

  In the present invention, the tip end portion of the fixed side yoke has, for example, a shape in which the slit width on the movable body side is equal to or narrower than the slit width on the coil side. .

  In this invention, it is preferable that the spacer which consists of a nonmagnetic material which connects the said front-end | tip parts is arrange | positioned between the said front-end | tip parts. If comprised in this way, it can prevent that a front-end | tip part will be attracted | sucked by a magnet and will deform | transform.

  In the present invention, it is preferable that the outer peripheral surface of the first movable body side yoke projects from the outer peripheral surface of the pair of magnets to the outer peripheral side. With this configuration, even when the fixed body side yoke is provided, the magnetic attractive force acting on the movable body in the direction perpendicular to the axial direction can be reduced. Therefore, there are advantages that it is easy to perform assembly work and the movable body is not easily tilted.

  In the present invention, it is preferable that a second movable body side yoke is laminated on each of the pair of magnets on the side opposite to the first movable body side yoke. Also in this case, it is preferable that the outer peripheral surface of the second movable body side yoke projects from the outer peripheral surface of the pair of magnets to the outer peripheral side. With this configuration, even when the fixed body side yoke is provided, the magnetic attractive force acting on the movable body in the direction perpendicular to the axial direction can be reduced. Therefore, there are advantages that it is easy to perform assembly work and the movable body is not easily tilted.

  In the present invention, the movable body includes a support shaft extending in at least one axial direction, and in the fixed body, a bearing that supports the support shaft movably in the axial direction in an opening opening in the axial direction. It is preferable that the member is held. If comprised in this way, it is not necessary to arrange | position a bearing member separately. Further, since the bearing member can be fixed on the basis of the fixed body, there is an advantage that the support shaft does not tilt.

  In the present invention, the movable body includes a support shaft extending in at least one axial direction, and at least the first movable body-side yoke and the magnet have a through hole or a non-insertion hole. It is preferable that a through hole is formed. If comprised in this way, centering of a spindle, a 1st movable body side yoke, and a magnet can be performed easily.

  In the present invention, it is preferable that an urging member for urging the movable body in at least one direction in the axial direction is disposed on the movable body.

  The actuator according to the present invention can be used, for example, as a drive device for a valve device. In this case, the fluid delivery is controlled by opening / closing the flow path or increasing / decreasing the cross-sectional area of the flow path by the axial movement of the movable body by energizing the actuator or the like. The movable body is preferably connected to a valve body for controlling fluid delivery by opening and closing the flow path or increasing or decreasing the cross-sectional area of the flow path. If comprised in this way, a valve body can be directly linearly driven. In such a case, it is preferable that the valve body is disposed on each of both sides of the movable body in the axial direction. With such a configuration, it is possible to control the fluid delivery to the two flow paths. .

  In the present invention, since the pair of magnets in the movable body have the same polarity directed to the first movable body side yoke, a strong magnetic flux is generated in the radial direction from the first movable body side yoke. Therefore, if the first movable body side yoke and the peripheral surfaces of the coils are opposed to each other, a large thrust can be applied to the movable body. In addition, since the magnet only needs to be magnetized in the axial direction, unlike the case where the magnet is magnetized in the radial direction, the magnet can be easily magnetized even if it is downsized, and is suitable for mass production. Moreover, since the configuration of the magnetic circuit is simple, it is suitable for downsizing. In addition, unlike the solenoid system, the magnet takes up much of the magnetic flux, so it consumes less current and requires about half the volume to achieve the same stroke and thrust. Can do.

  A linear actuator to which the present invention is applied will be described with reference to the drawings.

(overall structure)
1 (a) and 1 (b) are an explanatory view when a main part of a linear actuator to which the present invention is applied is cut in an axial direction, and an explanatory view showing lines of magnetic force of the linear actuator. is there.

  1A and 1B, a linear actuator 1 according to this embodiment is used for a valve device or a compressor device for supplying various fluids, and includes a cylindrical fixed body 3 and the fixed body 3. And a movable body 5 having a substantially cylindrical shape disposed on the inside. The fixed body 3 includes a coil 33 that is wound around the bobbin 31 in an annular shape, and wraps around both sides in the axial direction of the coil 33 from the outer peripheral surface of the coil 33, and one tip portion 36 a and the other tip portion 36 b of the coil 33. The fixed body side yoke 35 which opposes in an axial direction through the slit 37 on the inner peripheral side is provided. The movable body 5 includes a disk-shaped first movable body side yoke 51 and a pair of magnets 53 a and 53 b stacked on both sides in the axial direction with respect to the first movable body side yoke 51. As the pair of magnets 53a and 53b, Nd—Fe—B or Sm—Co rare earth magnets or resin magnets can be used. In the movable body 5, the second movable body side yokes 55 a and 55 b are laminated on the end surface opposite to the first movable body side yoke 51 in each of the pair of magnets 53 a and 53 b.

  In this embodiment, each of the pair of magnets 53 a and 53 b is magnetized in the axial direction, and has the same polarity toward the first movable body side yoke 51. Hereinafter, in the present embodiment, the pair of magnets 53a and 53b will be described as having the north pole facing the first movable body side yoke 51 and the south pole facing the outside in the axial direction. Vice versa.

  Here, the outer peripheral surface of the first movable body side yoke 51 protrudes from the outer peripheral surface of the pair of magnets 53a and 53b to the outer peripheral side. Further, the outer peripheral surfaces of the second movable body side yokes 55a and 55b also project from the outer peripheral surfaces of the pair of magnets 53a and 53b to the outer peripheral side.

  In addition, concave portions are formed on both end surfaces in the axial direction of the first movable body side yoke 51, and a pair of magnets 53a and 53b are fitted into these concave portions and fixed with an adhesive or the like. Note that the first movable body side yoke 51, the pair of magnets 53a and 53b, and the second movable body side yokes 55a and 55b may be fixed by bonding, press-fitting, or a combination thereof.

  In addition, bearing plates 71a and 71b (bearing members) are fixed to openings on both sides in the axial direction of the fixed body 3, and support shafts 57a projecting from the second movable body side yokes 55a and 55b to both sides in the axial direction. , 57b are slidably inserted into the holes of the bearing plates 71a, 71b. In this way, the movable body 5 is supported by the fixed body 3 so as to be capable of reciprocating in the axial direction. In this state, the movable body 5 has the outer peripheral surface facing the inner peripheral surface of the fixed body 3 with a predetermined gap, and the distal end portions 36a and 36b of the fixed body side yoke 35 are the first movable body side yoke. It is in the state which opposes in an axial direction within the clearance gap between the outer peripheral surface of 51, and the internal peripheral surface of the coil 33. FIG. A gap is secured between the movable body 5 and the fixed body side yoke 35. Note that the second movable body side yokes 55a and 55b and the support shafts 57a and 57b may be fixed by bonding, press-fitting, or a combination thereof.

(Operation)
In the linear actuator 1 configured as described above, a period in which a current flows from the far side to the near side on the left side in the drawing and a current flows in the coil 33 from the near side to the far side on the right side in the drawing. Then, the lines of magnetic force are expressed as shown in FIG. Therefore, first, the movable body 5 receives the thrust upward in the axial direction by the Lorentz force as shown by the arrow U and rises. On the other hand, when the energization direction to the coil 33 is reversed, the movable body 5 descends along the axial direction as indicated by an arrow D. Therefore, when an alternating current is applied to the coil 33, the movable body 5 performs a reciprocating linear motion in the axial direction.

(Main effects of this form)
As described above, in this embodiment, the pair of magnets 53a and 53b are directed to the same pole in the movable body 5, and a magnetic repulsive force is acting on them. Since the movable body side yoke 51 is disposed, the pair of magnets 53a and 53b can be fixed with the same poles directed.

  Further, in the movable body 5, the pair of magnets 53 a and 53 b have the same polarity directed to the first movable body side yoke 51, so that a strong magnetic flux is generated in the radial direction from the first movable body side yoke 51. Therefore, if the peripheral surfaces of the first movable body side yoke 51 and the coil 33 are opposed to each other, a large thrust can be applied to the movable body 5.

  Further, since the magnets 53a and 53b may be magnetized in the axial direction, unlike the case where the magnets 53a and 53b are magnetized in the radial direction, the magnets 53a and 53b can be easily magnetized even when downsized, and are suitable for mass production. .

  Moreover, in this embodiment, since the outer peripheral surface of the first movable body side yoke 51 protrudes from the outer peripheral surface of the pair of magnets 53a and 53b to the outer peripheral side, even when the fixed body side yoke 35 is provided, the movable body 5 On the other hand, the magnetic attractive force acting in the direction perpendicular to the axial direction can be reduced. Similarly, since the outer peripheral surface of the second movable body side yoke 55a, 55b protrudes from the outer peripheral surface of the pair of magnets 53a, 53b to the outer peripheral side, even when the fixed body side yoke 35 is provided, Thus, the magnetic attractive force acting in the direction perpendicular to the axial direction can be reduced. Therefore, there is an advantage that the assembly work is easy to perform and the movable body 5 is difficult to tilt.

  In this embodiment, since the magnets 53a and 53b are arranged on the outer peripheral side of the coil 33, the magnets 53a and 53b may be smaller than the case where the magnets 53a and 53b are arranged outside the coil 33. The actuator 1 can be configured at low cost. In addition, since the coil 33 is disposed outside, the magnetic path can be closed only by the fixed side yoke.

  Furthermore, in the fixed body 3, since the bearing plates 71a and 71b for supporting the support shafts 57a and 57b so as to be movable in the axial direction are held in the openings that are open in the axial direction, it is necessary to separately arrange the bearing members. There is no. Further, since the bearing plates 71a and 71b can be fixed on the basis of the fixed body 3, there is an advantage that the support shafts 57a and 57b are not inclined.

[Other embodiments]
In the modifications described below, the basic configuration is the same as that of the above-described embodiment. Therefore, common portions are denoted by the same reference numerals, and the descriptions thereof are as follows. Omitted.

(Modification of fixed body 3)
2A, 2B, and 2C are modifications of the fixed body 3 in the linear actuator 1 to which the present invention is applied.

  In the linear actuator 1 shown in FIGS. 1 (a) and 1 (b), the position where the one end portions 36a and 36b of the fixed body side yoke 35 oppose each other is substantially at the center in the axial direction. As shown, the position (slit 37) where the tip portions 36a and 36b face may be shifted from the central position in the axial direction to one side, for example, the lower side. If comprised in this way, the raising speed and descending speed of the movable body 5 can be made different. Therefore, it is possible to adjust the speed at which the fluid is guided to the pump chamber and the speed at which the fluid is discharged from the pump chamber in a valve device described later. Further, with respect to the shape of the tip portions 36a, 36b of the fixed body side yoke 35, a taper is provided from the outer peripheral side to the inner peripheral side with respect to the end surface, and the tip portion 36a is provided on the inner peripheral side (side closer to the movable body 5). , 36b may be adjacent to each other. If comprised in this way, the slit 37 width | variety by the side of the movable body 5 can be made narrower than the slit 37 width | variety by the side of the coil 33 in the front-end | tip parts 36a and 36b of a fixed side yoke.

  As shown in FIG. 2B, the fixed body side yoke 35 of the linear actuator 1 may be constituted by two yoke members arranged in the axial direction. In this case, the fixed body 3 can be assembled such that the bobbin 31 around which the coil 33 is wound is sandwiched from both sides in the axial direction, and the efficiency of the assembly work can be increased. Further, with respect to the shapes of the tip portions 36a and 36b of the fixed body side yoke 35 of the linear actuator 1, by providing a stepped portion that protrudes from the outer peripheral side to the inner peripheral side, the inner peripheral side (the side close to the movable body 5) is provided. ), The tip portions 36a and 36b may be close to each other. If comprised in this way, the slit 37 width | variety by the side of the movable body 5 can be made narrower than the slit 37 width | variety by the side of the coil 33 in the front-end | tip parts 36a and 36b of a fixed side yoke.

  As shown in FIG. 2 (c), the tips 36a, 36b of the fixed body side yoke 35 of the linear actuator 1 are tapered from the outer peripheral side to the inner peripheral side with respect to the end surface, and in the middle A configuration in which the tip portions 36a and 36b are close to each other on the inner peripheral side (side close to the movable body 5) in a state where the annular grooves 361a and 361b are formed at the positions may be adopted. Moreover, if the spacer which consists of a nonmagnetic material engaged with the cyclic | annular groove | channels 361a and 361b is fitted between the front-end | tip parts 36a and 36b, the front-end | tip parts 36a and 36b can be connected. As a result, it is possible to prevent the tip portions 36a and 36b from being attracted by the magnets 53a and 53b and deformed.

(Modification on the movable body 5 side)
3 (a), (b), (c), FIG. 4, FIG. 5 (a), (b), and (c) are modified examples of the movable body 5 in the linear actuator 1 to which the present invention is applied.

  In the linear actuator 1 shown in FIGS. 1A and 1B, recesses into which the magnets 53a and 53b are fitted are formed on both end surfaces in the axial direction of the first movable body side yoke 51. However, FIG. As shown in FIG. 4, the both end surfaces in the axial direction of the first movable body side yoke 51 may be flat, and the magnets 53a and 53b may be fixed to these flat end surfaces with an adhesive or the like.

  As shown in FIG. 3B, the first movable body side yoke 51, the pair of magnets 53a and 53b, and the second movable body side yokes 55a and 55b are fixed with an adhesive 59 or the like while being separated in the axial direction. It may be configured.

  As shown in FIG. 3 (c), through holes of predetermined sizes are formed in the center of the first movable body side yoke 51, the pair of magnets 53a and 53b, and the second movable body side yokes 55a and 55b. The stepped support shaft 57 may be fitted into the through hole. Here, the through hole becomes smaller in the order of the first movable body side yoke 51, the pair of magnets 53a and 53b, and the second movable body side yokes 55a and 55b. It is getting thinner toward. With this configuration, the first movable body side yoke 51, the pair of magnets 53a and 53b, and the second movable body side yokes 55a and 55b are inserted in order from both shaft ends of the stepped support shaft 57. Can be easily determined, and the first movable body side yoke 51, the pair of magnets 53a and 53b, and the second movable body side yokes 55a and 55b can be centered efficiently.

  As shown in FIG. 4, the support shaft 57 is not limited to a round bar, and a support shaft 57 made of a square bar such as a hexagonal bar may be used. In this case, the first movable body side yoke 51 and the pair A through hole having a shape corresponding to the support shafts 57a and 57b may be formed in the magnets 53a and 53b and the second movable body side yokes 55a and 55b. Further, the bearing plates 71a and 71b that support the support shaft 57 may be formed with bearing holes having a shape corresponding to the support shafts 57a and 57b. If comprised in this way, rotation around the axis line of the movable body 5 can be prevented.

  A through hole is formed in the pair of magnets 53a and 53b and the second movable body side yoke 55a and 55b, and a non-through hole is formed in the first movable body side yoke 51 and supported from both sides in the axial direction. The structure which inserts an axis | shaft may be sufficient.

  In any of the above forms, the first movable body side yoke 51, the pair of magnets 53a and 53b, and the second movable body side yokes 55a and 55b are all cylindrical, but for example, as shown in FIG. As described above, the first movable body side yoke 51 and the second movable body side yokes 55a and 55b may be prismatic shapes such as hexagonal columns.

  Further, for example, as shown in FIGS. 5B and 5C, the second movable body side yokes 55a and 55b may have a configuration in which the end surfaces thereof are not cylindrical and the end surfaces thereof are curved. The planar shape may be an ellipse, an oval, or a deformed shape that extends toward one side.

(Addition of biasing member)
FIGS. 6A, 6B, and 7 are modifications of the linear actuator 1 to which the present invention is applied.

  In the linear actuator 1 shown in FIGS. 1A and 1B, the movable body 5 is propelled only by magnetic force. For example, as shown in FIG. 6A, on one side in the axial direction, Between the bearing plates 71a and 71b and the second movable body side yokes 55a and 55b, a truncated cone-shaped coil spring 91 is disposed as an urging member. For example, when the movable body 5 descends, the compression is performed. When the movable body 5 moves at a low speed while deforming the spring, the shape restoring force of the compression spring may be assisted to move at a high speed.

  Further, as shown in FIG. 6B, coil springs 91 and 92 as urging members are disposed between the bearing plates 71a and 71b and the second movable body side yokes 55a and 55b on both sides in the axial direction. Alternatively, an urging force that always holds the movable body 5 at the center position (origin position) in the axial direction may be applied.

  When urging the movable body 5 in the axial direction, instead of the coil springs 91 and 92 as shown in FIGS. 6A and 6B, a gimbal spring 93 as shown in FIG. 7, a flat spring, or a bamboo spring is used. Etc. may be arranged.

  As shown in FIGS. 6 and 7, the fixed body side yoke 35 is formed with a coil wire drawing hole 350 for drawing a terminal end of the coil wire from the coil 33 at least at one position, for example, at an end located in the axial direction. It is preferable that the cylindrical portion 310 of the bobbin 31 is disposed in the coil drawing hole 350. If comprised in this way, the terminal of a coil wire can be pulled out easily.

(Other variations)
In the said form, it was the structure by which the movable body 5 was arrange | positioned inside the fixed body 3, However, by the structure by which the fixed body provided with the coil wound circularly was arrange | positioned inside the cyclic | annular movable body. There may be. In this case, the configuration is basically the same as that of the above embodiment except that the outer peripheral surface of the coil and the inner peripheral surface of the movable body face each other.

[Configuration example of valve device]
The linear actuator 1 which concerns on this invention can be used as a drive device of the valve apparatus 100 so that it may demonstrate below with reference to FIG. 8 and FIG. The linear actuator 1 used in the valve device 100 described below is common because the basic configuration is the same as that described with reference to FIGS. 1A and 1B. The parts are illustrated with the same reference numerals, and only the main part of the description of the linear actuator 1 is omitted.

  FIG. 8 and FIG. 9 are both explanatory views when the valve device 100 using the linear actuator 1 to which the present invention is applied as a drive device is cut in the axial direction and viewed obliquely from above.

  In the valve device 100 shown in FIG. 8, the linear actuator 1 suitable for the present invention is used in a state surrounded by a cylindrical housing 110, and below that is indicated by an arrow Lin and an arrow Lout by a flow path component 130. A pump chamber 170 having a flow path through which fluid flows is formed.

  As described with reference to FIGS. 1A and 1B, the linear actuator 1 used here controls the energization of the coil 33, whereby the movable body 5 reciprocates in the axial direction. Here, the lower ends of one of the support shafts 57 a and 57 b are connected to the central portion of the diaphragm valve 150. An annular thick portion 151 that functions as an O-ring is formed on the outer peripheral side of the diaphragm valve 150. In the diaphragm valve 150, the outer peripheral side including the annular thick portion 151 is between the housing 110 and the flow path component 130. Liquid tightness is ensured between the two. A check valve (not shown) is disposed on the in and out sides of the flow path. Here, the in side is generally kept at a high pressure with respect to the out side by a pressure generating means (not shown) prepared separately. Further, the in-side flow path is almost liquid-tightly sealed by the close contact of the bottom of the diaphragm valve 150 at the opening. Here, the operation of the diaphragm valve 150 in the direction indicated by the arrow U opens the opening of the in-side flow path, and quickly conducts the liquid to the out-side. On the contrary, the operation of the diaphragm valve 150 in the direction indicated by arrow D closes the opening of the in-side flow path or overcomes the pressure from the in-side to open it, and promptly conducts the liquid to the out-side. Stop. Such an operation can be effectively assisted if an urging spring is appropriately used. At that time, since the diaphragm valve 150 is directly connected to the support shafts 57a and 57b, the diaphragm valve 150 can be directly linearly driven.

  In addition, about a valve body, you may use not only the diaphragm valve 150 but a bellows valve and another valve body. Further, the support shafts 57a and 57b and the valve body may be configured as separate members, or the support shafts 57a and 57b and the valve body may be formed integrally.

  The basic configuration of the valve device 100 shown in FIG. 9 is the same as that of the valve device 100 described with reference to FIG. 8, and thus the description of the housing 110 and the flow path component 130 is omitted. The support shafts 57a and 57b on both sides of 1 are fixed to the diaphragm valve 150, respectively. For this reason, when the movable body 5 moves in the direction indicated by the arrow U or the direction indicated by the arrow D, the two diaphragm valves 150 are deformed in opposite directions. Therefore, in the two upper and lower pump chambers 170, the above-described operation (liquid suction and discharge) is performed exclusively.

  Depending on the configuration of the valve device 100, the upper and lower pump chambers 170 can be similarly expanded and contracted.

[Application to other devices]
8 and 9, the example in which the linear actuator 1 according to the present invention is used in the valve device 100 has been described. However, the linear actuator 1 according to the present invention is not limited to the valve device 100 for liquid feeding, You may use for various dynamic pressure control etc., such as the air valve apparatus 100. FIG. The linear actuator 1 alone may be used as a small linear propulsion device.

(A), (b) is explanatory drawing when the principal part of the linear actuator to which this invention is applied cut | disconnected in the axial direction seen from diagonally upward, and explanatory drawing which shows the magnetic force line of this linear actuator. (A), (b), (c) is a modification of the fixed body in the linear actuator to which this invention is applied. (A), (b), (c) is the modification of the movable body in the linear actuator to which this invention is applied. It is a modification of the movable body in the linear actuator to which this invention is applied. (A), (b), (c) is the modification of the movable body in the linear actuator to which this invention is applied. (A), (b) is a modification when a biasing member is provided in a linear actuator to which the present invention is applied. It is a modification at the time of providing a biasing member in the linear actuator to which the present invention is applied. It is explanatory drawing when the thing which cut | disconnected the axial direction the valve apparatus which used the linear actuator to which this invention is applied as a drive device was seen from diagonally upward. It is explanatory drawing when the thing which cut | disconnected the axial direction the valve apparatus which used the linear actuator to which this invention is applied as a drive device was seen from diagonally upward.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Linear actuator 3 Fixed body 5 Movable body 31 Bobbin 33 Coil 35 Fixed body side yoke 36a, 36b Tip part 37 of fixed body side yoke Slit 51 1st movable body side yoke 53a, 53b Magnet 55a, 55b 2nd movable body side yoke 57a, 57b Support shafts 71a, 71b Bearing plates 91, 92 Coil springs (biasing members)
93 Gimbal spring (biasing member)
100 Valve device 150 Diaphragm valve 170 Pump chamber

Claims (15)

A stationary body with a coil wound in a ring;
A first movable body side yoke whose circumferential surface faces the coil on the inner side or the outer side of the coil, and an axis line with respect to the first movable body side yoke with the same polarity directed toward the first movable body side yoke A movable body having a pair of magnets laminated on both sides in the direction,
The linear actuator, wherein the movable body is driven in an axial direction by energizing the coil. In Claim 1, the fixed body is disposed inside the coil,
A linear actuator, wherein an outer peripheral surface of the first movable body side yoke and an inner peripheral surface of the coil are opposed to each other. 3. The fixed body according to claim 2, wherein the fixed body wraps around both sides in the axial direction of the coil from the outer peripheral surface of the coil, and one front end portion and the other front end portion are the outer peripheral surface of the first movable body side yoke and the coil. A fixed body side yoke located in a gap with the inner peripheral surface of the
The tip portions of the fixed body side yokes face each other in the axial direction through a slit,
A linear actuator characterized in that a gap is secured between the fixed body side yoke and the movable body.   4. The linear actuator according to claim 3, wherein the fixed body side yoke is formed with a coil wire drawing portion for drawing a terminal end of the coil wire from the coil.   5. The tip portion of the fixed side yoke according to claim 3, wherein a slit width on the movable body side is equal to a slit width on the coil side or narrower than a slit width on the coil side. A linear actuator.   6. The linear actuator according to claim 3, wherein a spacer made of a nonmagnetic material that connects the tip portions is disposed between the tip portions of the fixed side yoke.   7. The linear actuator according to claim 3, wherein an outer peripheral surface of the first movable body side yoke projects from an outer peripheral surface of the pair of magnets to an outer peripheral side.   8. The linear actuator according to claim 3, wherein a second movable body side yoke is laminated on each of the pair of magnets on the side opposite to the first movable body side yoke. 9.   9. The linear actuator according to claim 8, wherein an outer peripheral surface of the second movable body side yoke projects from the outer peripheral surface of the pair of magnets to the outer peripheral side. In any one of Claims 1 thru | or 9, The said movable body is provided with the spindle which extended in at least one direction of the axial direction,
A linear actuator, wherein a bearing member that supports the support shaft so as to be movable in the axial direction is held in an opening portion that opens in the axial direction in the fixed body. In any one of Claims 1 thru | or 9, While the said movable body is provided with the spindle which extended in at least one direction of the axial direction,
A linear actuator, wherein a through hole or a non-through hole into which the support shaft is inserted is formed in at least the first movable body side yoke and the magnet.   12. The linear actuator according to claim 1, wherein an urging member that urges the movable body in at least one direction in an axial direction is arranged with respect to the movable body. A valve device comprising a linear actuator as defined in any one of claims 1 to 12,
A valve device that controls fluid delivery by opening and closing a flow path or increasing or decreasing a cross-sectional area of the flow path by an operation in an axial direction of the movable body by energization or the like.   14. The valve device according to claim 13, wherein the movable body is connected to a valve body for controlling fluid delivery by opening / closing a flow path or increasing / decreasing a cross-sectional area of the flow path.   15. The valve device according to claim 13, wherein the valve bodies are respectively disposed on both sides of the movable body in the axial direction.

Images