JP2006262698A - Actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To decrease the input to an excitation coil, and to reduce the size of a drive part, by reducing the load on the rotor. <P>SOLUTION: The actuator is operated, without generating contact resistance for an airtight seal by providing the excitation coil 33 and by airtightly separating through a partition wall 40 a stator 32 placed in a stationary state and a rotor 30 actuated to rotate. Energizing the force of an energization unit 39 for further axially energizing a flow-regulating body 38 is actuated between it and a moving body 36 so that the energizing force of the energizing unit 39 is prevented from serving as the load resistance, relating to the rotation of the rotor 30. In this way, with a sure airtight sealing structure due to the partition, a frictional resistance loss by the airtight seal can be prevented, and the load resistance due to the energizing force to the flow regulation body is eliminated to make the load reducible to the rotor, so that decrease in the input to the excitation coil and to miniaturize the drive part of the rotor or the stator and the like can be attained. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an actuator that controls the flow of fluid in a flow path.

  Conventionally, there is an actuator of this type as shown in Patent Document 1. The configuration will be described below with reference to FIGS.

  FIG. 9 shows a first conventional example in which a valve body 2 is provided opposite to a valve seat 1 in a fluid passage. The valve body 2 is provided with a valve body 2 on a flange 5 attached to an opening 4 of the fluid passage 3. It is attached via a spring 6 that urges the valve seat 1 in a pressing direction. Reference numeral 7 denotes a valve stem having a valve body 2 connected to one end. The valve stem 7 extends through the through hole 8 of the flange 5 and extends out of the fluid passage, and is located in the middle of the valve stem 7 in the axial direction. The feed male screw 9 is formed. Reference numeral 10 denotes a feed female screw formed on the inner peripheral surface of the rotor 11, and this feed female screw 10 is screwed into the feed male screw 9. 12 is a permanent magnet provided on the outer peripheral side of the rotor 11, 13 is a stationary electromagnetic coil provided so as to face the permanent magnet 12 through a gap, and 14 is a bearing provided at both ends of the rotor 11 to support the rotation of the rotor 11. , 15 are mounting plates fixed to the flange 5. Reference numeral 16 denotes an O-ring provided in the through hole 8 for preventing the fluid in the fluid passage 3 from the gap between the valve stem 7 and the flange 5 from leaking to the outside. Reference numeral 17 denotes an anti-rotation portion that is provided at the end of the valve stem 7 and prevents the valve stem 7 from rotating. In this configuration, the electromagnetic coil 13 is energized to rotate the rotor 11, and the valve rod 7 screwed into the rotor 11 is linearly moved in the axial direction.

FIG. 10 shows a second conventional example, in which the O-ring 16 that contacts the valve stem 7 of the first conventional example is eliminated. A rotor 18 is provided with a permanent magnet 19 on the outer peripheral side, and a rotary shaft 20 fixed to the rotor 18 has a feed male screw 21 at an end thereof. Reference numeral 22 denotes a non-magnetic pipe disposed on the outer peripheral side of the rotor 18 with a gap. An electromagnetic coil 23 is provided on the outer peripheral side of the pipe 22, and O-rings 24 as seal members are provided at both ends of the pipe 22. A motor is formed by providing a spring 26 between the motor mounting plate 25 and the valve body 2, and a valve body moving means 27 connected to the valve body 2 at the end is screwed to the feed male screw 21 of the rotary shaft 20. is there. Reference numeral 28 denotes a rotation stopper for preventing the valve body moving means 27 attached to the motor attachment plate 25 from rotating. In this configuration, the fluid in the fluid flow path 3 is prevented from leaking to the outside by the O-ring 24 of the pipe 22 part.
JP-A-5-71655

  However, in the first conventional example, in the seal structure using the O-ring 16 provided between the through hole 8 and the valve stem 7, the O-ring 16 is in close contact with the valve stem 7. Resistance must be generated to increase the driving force, leading to an increase in the size and input of the drive portion of the shut-off valve. Further, due to secular change, the O-ring 16 is fixed to the valve stem 7 and the operation of the valve body 2 is obstructed, which causes a problem in reliability.

In the second conventional example, since the valve body 2 is constantly urged by the spring 26, the motor constantly receives resistance due to the urging force of the spring 26 during its operation. That is, it is necessary to overcome the urging force of the spring 26 and move the valve body 2 when the valve is opened, and the urging force of the spring 26 is applied as an axial thrust to the feed screw portion at any time when the valve is opened and closed. Generates frictional resistance. Thus, since the biasing force of the spring 26 acts as a load resistance for the motor, it is necessary to increase the output of the motor, leading to an increase in motor input and an increase in size of the motor. There was a problem.

  In particular, when a motor is driven by a battery having a limited capacity or a limited voltage, low input and high output are major issues that determine the feasibility of practical use.

  In order to solve the above-mentioned problems, the present invention allows a stationary stator having an exciting coil and a rotating rotor to be hermetically separated by a partition so as to operate without generating contact resistance for hermetic sealing. Further, the urging force of the urging body that urges the flow restricting body in the axial direction is applied between the moving body and the urging force of the urging body during the movement of the moving body is a load resistance against the rotation of the rotor. It is something that is not.

  According to the above invention, it is possible to prevent a loss of frictional resistance due to the airtight seal with the reliable airtight seal structure by the partition wall, and it is possible to reduce the load on the rotor by eliminating the load resistance due to the urging force to the flow restricting body. Low input and downsizing of the drive unit such as the rotor or stator can be realized.

  As is clear from the above description, according to the actuator of the present invention, the flow restricting body connected to the moving body so as to be movable in the axial direction through the biasing body biased in the axial direction, the rotor, and the stator A partition wall that is disposed on one end face side of the rotor and the rotor and that is integrally formed to hermetically separate the stator and the rotor on the fluid side, a mounting body on which the partition wall and the stator are mounted, a moving body provided on the mounting body A rotation preventing body that restricts rotation of the liquid, a first seal provided between the flange portion of the partition wall and the mounting body, and a second seal provided between the fluid and the mounting plate. It is a reliable airtight seal structure that prevents frictional resistance loss due to the airtight seal, and it can reduce the load resistance by the urging force between the moving body and the flow restricting body, reducing the load on the rotor. Lower stator input Has the effect of that can be further downsized driving unit, such as a rotor or stator.

  A rotor having magnetic poles, a stator having an exciting coil, a rotor rotating shaft provided on the rotor, a feeding means provided on the rotor rotating shaft, a moving body screwed or engaged with the feeding means, and an axial direction A flow restricting body that is connected to the moving body so as to be movable in the axial direction through an urging body that urges the rotor, and is disposed on and integrated with a gap between the rotor and the stator and one end surface of the rotor. And a partition wall that hermetically separates the stator and the rotor on the fluid side, an attachment body to which the partition wall and the stator are attached, and a rotation prevention provided on the attachment body to restrict the rotation of the moving body A body, a first seal provided between the flange portion of the partition wall and the attachment body, and a second seal provided between the fluid and the attachment plate.

  And, it can be a reliable and reliable airtight seal structure by the partition wall, prevents frictional resistance loss due to the airtight seal, and prevents the biasing force to the flow restricting body from acting as a load resistance on the rotation of the rotor, It is possible to reduce the input of the stator and reduce the size of the drive unit such as the rotor or the stator.

  In addition, the shaft has a shaft hole provided at the center of the rotor rotation shaft and a support shaft that is inserted into the shaft hole and supports the rotation of the rotor, and the support shaft is fixed to the partition wall. The rotor is supported by the support shaft at a small diameter portion, the frictional resistance is reduced by reducing the contact radius, and the low input is promoted. Further, the actuator can be downsized by downsizing the shaft support structure.

Further, one end of the support shaft is joined to the shaft support, and this shaft support is joined to the partition wall. And even when the partition wall is made of an extremely thin material, the support shaft can be securely attached to the partition wall with increased bonding strength, and the durability of the partition wall can be increased by increasing the output power and the structure strength. It is possible to improve reliability.

  The shaft support is made of a magnetic material. Even if the partition walls are made of a nonmagnetic material, the magnetic material can be arranged on the side of the rotor, so that the magnetic resistance of the magnetic circuit between the rotor and the stator can be reduced, the magnetic driving force can be improved, and the rotational force can be increased. realizable.

  Further, a sealing portion is provided on the flow regulating body side of the shaft hole of the rotor rotation shaft. Further, it is possible to prevent dust and foreign matter from entering the support shaft portion from the flow regulating body side, and it is possible to maintain stable rotation and improve reliability. Further, it is possible to prevent wear powder generated at the support shaft portion or the applied lubricant from flowing out to the fluid side, and it can be used for a clean fluid.

  Further, the flow restricting body and the moving body are connected by a locking portion provided with a backlash in the radial direction so that the flow restricting body can swing freely with respect to the moving body. And if there is an error in the mounting of the actuator to the fluid passage, for example, even if it is installed tilted with respect to the valve seat, the flow restrictor can normally close the valve seat of the fluid passage by swinging motion, and reliable fluid control It is possible to realize further improvement in reliability by the operation.

  In addition, a bearing that supports the outer periphery of the rotor rotation shaft and a bearing holding portion that is integrally formed with the partition wall are provided, and the bearing is held by the bearing holding portion. Since the bearing holding part is integrally formed with the partition wall, the clearance between the rotor and the partition wall can be further reduced by high-precision processing without misalignment, and the strength of the partition wall can be improved by forming irregularities, so that the partition wall thickness is reduced. Can be further promoted, and the rotational force of the rotor can be improved.

An attachment body to which the partition wall, the stator and the rotation preventing body are fixed, and a bearing body for receiving an axial thrust load of the rotor rotation shaft are provided between the attachment body and the rotor. In addition, the thrust load generated in the axial direction prevents the rotor from moving in the axial direction and comes into contact with components such as a partition wall or a mounting body, and prevents dust and foreign matter from entering the rotor side from the fluid side. In the following, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the present embodiment.

(Embodiment 1 and Embodiment 2)
FIG. 1 is a cross-sectional view showing the valve opening state of the actuator according to the first and second embodiments of the present invention, and FIG. 2 shows the valve closing state of the actuator according to the first and second embodiments of the present invention. It is sectional drawing shown. In FIG. 1, reference numeral 30 denotes a rotor having a magnetic pole 31 made of a permanent magnet on the outer periphery, 32 denotes a stator formed of a magnetic material that surrounds the exciting coil 33, and the stator 32 faces the outside of the magnetic pole 31 of the rotor 30. Has been placed. Reference numeral 34 denotes a rotor rotation shaft provided on the rotor 30, and a feed means 35 is provided on the outer periphery of the rotor rotation shaft 34. In this embodiment, a male screw with a spiral groove (or protrusion) is used as the feed means 35. ing. Reference numeral 36 denotes a moving body provided with a female screw that is screwed to the feeding means 35, and reference numeral 37 denotes a rotation preventing body that prevents the moving body 36 from rotating with respect to the rotor rotating shaft 34.

Reference numeral 38 denotes a flow restricting body that is disposed in the fluid passage 3 and restricts the flow state of the fluid. The flow restricting body 38 is connected to the moving body 36 so as to be movable in the axial direction. Reference numeral 39 denotes an urging body that is interposed between the moving body 36 and the flow restricting body 38 and applies an urging force to be separated from each other in the axial direction. The flow restricting body 38 has a valve rubber plate 38a contacting the valve seat 1 attached to the valve rubber holding portion 38b and fixed with a valve rubber presser 38c. Reference numeral 40 is a partition wall that hermetically separates the rotor 30 on the fluid side and the flow regulating body 38 side that is connected to the rotor 30 and the stator 32 side, and the partition wall 40 is a small distance (0) from the rotor 30 in the gap between the rotor 30 and the stator 32. The cylindrical portion 40a and the side surface portion 40b disposed on one end surface side of the rotor 30 are integrally formed of a nonmagnetic material.

  Reference numeral 41 denotes a support shaft having one end fixed to the cylindrical portion 40 a of the partition wall 40, and the support shaft 41 is inserted into a shaft hole 42 provided at the center of the rotor rotation shaft 34 to support the rotation of the rotor 30. Reference numeral 41 a denotes a relief portion provided on the support shaft 41, so that the tip end portion and the root portion of the support shaft 41 are surely in contact with the shaft hole 42. Here, although the case where the feeding means 35 and the moving body 36 are screwed together by continuous spiral peaks and grooves has been considered, the spiral peaks and grooves may be discontinuous, and the continuous spiral peaks and grooves may be discontinuous. A point contact method having several contact points with respect to a mountain or a valley may be used. Reference numeral 43 denotes an attachment body to which the partition wall 40 and the stator 32 are attached. The attachment body 43 is provided with a through hole 43a through which the rotor rotating shaft 34 passes. 44 is a side plate that covers the stator 32 and the side surface portion 40b of the partition wall 40, 45 is an O-ring (first seal) provided between the flange portion 40c of the partition wall 40 and the mounting body 43, and 46 is attached to the fluid passage 3. An O-ring (second seal) that hermetically seals between the bodies 43.

  Next, the operation will be described. First, a drive circuit (not shown) connected to the excitation coil 33 of the stator 32 sequentially energizes the excitation coil 33 in the direction to close the valve to apply electromagnetic force to the magnetic poles of the rotor 30 to center the rotor 30 on the support shaft 41. And a force is applied to the moving body 36 screwed onto the rotor rotating shaft 34. Since the moving body 36 is prevented from rotating by the rotation preventing body 37, it moves toward the valve seat 1 along with the rotation of the rotor rotating shaft 34. At this time, the flow restricting body 38 connected to the moving body 36 moves toward the valve seat 1 together with the moving body 36. During this movement, the biasing force of the biasing body 39 is a load against the rotational force of the rotor 30. Don't be.

  However, when the flow restricting body 38 comes into contact with the valve seat 1, the urging force of the urging body 39 acts as a load on the rotor 30, and the rotational force of the rotor 30 moves so as to compress the urging body 39 by a small amount. The body 36 is moved toward the valve seat 1. When the urging body 39 is slightly compressed to stop the rotation of the rotor 30, the urging force of the urging body 39 is applied so as to press the flow restricting body 38 against the valve seat 1, and a stable valve closing force is obtained. The valve is closed in the added state. FIG. 2 shows a state where the flow restricting body 38 closes the valve seat 1 in a state where the valve closing force is applied.

  Next, when the flow restrictor 38 is moved away from the valve seat 1 in the opening direction, the drive circuit (not shown) is switched and driven so that the rotation direction of the rotor 30 is the reverse direction. In the process in which the urging force of the urging body 39 is applied to the valve seat 1 in the valve opening operation, this urging force acts as a force for rotating the rotor 30 in the valve opening direction, so that the load for rotating the rotor 30 is reduced. . Particularly, when the pressure difference of the fluid occurs between the upstream and downstream of the valve seat 1 when the valve is closed and the flow restricting body 38 in the drawing has a high pressure, the force for pressing the flow restricting body 38 against the valve seat 1 Although acting as (back pressure), the urging force of the urging body 39 acts in a direction to reduce the back pressure, so the load at the time of valve opening is reduced.

  When the flow restricting body 38 moves away from the valve seat 1, the urging force of the urging body 39 becomes independent of the load of the rotor 30, and the flow restricting body 38 is moved to the valve opening position (shown in FIG. 1) by the rotation of the rotor 30. Then, the rotation of the rotor 30 is stopped by a drive circuit (not shown). In addition, by configuring the rotor 30 and the stator 32 as so-called stepping motors that drive the rotation of the rotor 30, the accuracy of the valve closing position and the valve opening position can be easily increased, and the drive frequency applied to the excitation coil 33. The (pulse rate) can be changed according to the load.

  The rotation of the rotor 30 is rotatably supported by a support shaft 41 inserted into a shaft hole 42 provided at the center of the rotor rotation shaft 34, and the inner peripheral surface, not the outer peripheral surface of the rotor rotation shaft 34, is supported. The torque loss due to the frictional force is reduced by reducing the contact radius as a sliding surface.

  In the above operation, since the stator 32 having the exciting coil 33 is provided with the airtight seal structure provided outside the fluid passage by the partition wall 40 crossing the magnetic circuit, the contact resistance due to the airtight seal is eliminated and the airtight seal load on the rotor 30 is eliminated. It is a thing. In addition, although the flow restricting body 38 is urged in the axial direction by the urging body 39, the urging force of the urging body 39 becomes an internal force applied between the moving body 36 and the flow restricting body 38, and the moving body 36. The flow regulating body 38 and the biasing body 39 move together. For this reason, the urging force is only a load on the rotor 30 only when the flow restricting body 38 abuts on the valve seat 1, and when the flow restricting body 38 moves away from the valve seat 1, the urging force is not applied to the rotor 30. The load can be reduced without the load on the valve, and the biasing force of the biasing member 39 acts to reduce the back pressure applied to the flow restricting member 38 when the flow restricting member 38 is opened away from the valve seat 1. The load on the rotor 30 when the valve is opened can be reduced.

  Further, by inserting the support shaft 41 into the shaft hole 42 provided in the inner diameter direction of the rotor rotation shaft 34, it is not necessary to provide the rotation support portion in the axial direction, so that the shaft support configuration can be downsized. Since the inertia is reduced, the load on the rotor 30 can be reduced or the responsiveness when the rotor 30 rotates can be improved.

  As described above, in the first embodiment, the airtight seal structure by the partition wall 40 and the frictional resistance loss due to the airtight seal can be prevented, and the load resistance is reduced by the urging force between the moving body 36 and the flow restricting body 38. Thus, the load on the rotor can be reduced, and the input of the stator 32, which is a drive unit, can be reduced, and the drive unit such as the rotor 30 or the stator 32 can be downsized.

  Further, in the second embodiment, the rotor 30 is supported by the small-diameter support shaft 41, whereby the frictional resistance is reduced by the reduction of the contact radius, and the low input to the drive unit is promoted, and the shaft support structure is further downsized. This makes it possible to reduce the size of the actuator.

(Embodiment 3 and Embodiment 4)
FIG. 3 is a sectional view of the actuator according to the third and fourth embodiments of the present invention. In the figure, the same members and the same functions as those of the embodiment of FIGS. 1 and 2 are denoted by the same reference numerals, detailed description thereof will be omitted, and different points will be mainly described.

  Reference numeral 47 denotes a shaft support in which one end of the support shaft 41 is joined. The shaft support 47 is further joined to the fluid passage 3 side of the side surface portion 40 b of the partition wall 40. The shaft support 47 is accurately finished so that the outer shape conforms to the inner shape of the cylindrical portion 40a of the partition wall 40, and an opening 47a is provided at the center thereof to fit the end portion of the support shaft 41 so that the cylindrical portion of the partition wall 40 is fitted. The support shaft 41 is arranged in the center of 40a without misalignment. The joining of the support shaft 41 to the shaft support 47 and the joining of the shaft support 47 to the partition wall 40 can be easily performed by welding or the like. A thrust bearing 48 receives the axial thrust load of the rotor 30 and ensures smooth operation of the rotor rotating shaft 34 even when the biasing force of the biasing body 39 is applied when the valve is closed. Further, by using the shaft support 47 as a magnetic material, the magnetic material can be disposed in the vicinity of the side surface of the magnetic pole 31 of the rotor 30, and the magnetic resistance of the magnetic circuit on the side surfaces of the rotor 30 and the stator 32 is reduced.

For this reason, the support shaft 41 can be supported with increased strength by increasing the thickness of the shaft support 47, and the strength of the partition 40 can be increased by joining the strong shaft support 47 to the partition 40. Can do. By the way, the magnetic gap which is the distance between the rotor 30 and the stator 32 becomes a resistance of the magnetic circuit and should be set as small as possible. Therefore, the partition 40 disposed between the rotor 30 and the stator 32 is thin. Necessary. In particular, when the partition wall 40 is formed by drawing with excellent productivity, the side surface portion 40b is thin, and it is difficult to join the support shaft 41 directly in terms of strength. However, if the support shaft 41 is installed via the shaft support 47 having strength, the formation of the partition wall 40 and the reinforcement of the partition wall 40 by the drawing process of the ultrathin plate can be compatible and the productivity can be improved.

  Further, when the shaft support 47 is made of a magnetic material, the magnetic circuit resistance between the rotor 30 and the stator 32 facing each other is reduced. Therefore, when the excitation coil 33 is energized, the magnetic part in which the cylindrical portion 40a of the partition wall 40 is interposed. A larger magnetic flux can be generated in the gap portion, and the electrical input to the exciting coil 33 for increasing the rotational force of the rotor 30 and obtaining a predetermined rotational force can be reduced. In particular, since the partition wall 40 is disposed between the rotor 30 and the stator 32 facing each other, the partition wall 40 needs to be made of a nonmagnetic material. When the cylindrical portion 40a and the side surface portion 40b are integrally formed, the magnetic material shaft support 47 is used. The magnetic circuit can be improved by reducing the magnetic resistance.

  As described above, in the third embodiment, even when the partition wall 40 is formed of an extremely thin material, the support shaft 41 can be securely attached to the partition wall 40 with an increased bonding strength. Reliability and durability can be improved by increasing the output and strengthening the structure, and productivity can be further improved.

  Furthermore, in the fourth embodiment, even if the partition 40 is made of a nonmagnetic material, a magnetic material can be disposed on the side surface of the rotor 30, so that the magnetic resistance of the magnetic circuit between the rotor 30 and the stator 32 can be reduced and the magnetic driving force can be reduced. It is possible to improve the output of the rotational force or reduce the input of the drive unit.

(Embodiment 5)
FIG. 4 is a sectional view of the actuator according to the fifth embodiment of the present invention. In the figure, the same members and the same functions as those in the embodiment of FIGS.

  A sealing portion 49 is provided on the flow restricting body 38 side so that the shaft hole 42 formed in the rotor rotating shaft 34 does not open on the flow restricting body 38 side.

  For this reason, it is possible to prevent dust, foreign matter and the like from entering the support shaft 41 from the flow regulating body 38 side facing the fluid passage 3, and wear powder generated at the support shaft 41 or lubricant that has been applied, etc. Can be prevented from leaking out to the fluid passage 3 side. The shaft hole 42 may be a blind hole opened so that the tip does not open from the rotor 30 side, but a sealing plug is provided after machining as a through hole that can be processed with high accuracy and the dimensions of the inlet and tip can be confirmed. By using the sealing portion 49, the workability and reliability of the shaft hole 42 can be improved.

  As described above, it is possible to prevent dust and foreign matter from entering the support shaft 41 from the flow restricting body 38 side, and it is possible to maintain stable rotation and improve durability and reliability. Further, it is possible to prevent wear powder generated at the support shaft 41 portion or applied lubricant from flowing out to the fluid passage side, thereby preventing the contamination of the fluid and using it for a clean fluid, thereby expanding the applicable range. be able to.

(Embodiment 6)
FIG. 5 is a partial sectional view of the actuator according to the sixth embodiment of the present invention. In the figure, the same members and the same functions as those in the embodiment of FIGS.

  Reference numeral 50 denotes a locking portion that fits and locks an outer peripheral protrusion 36a provided on the moving body 36 extending in the outer peripheral direction and an inner peripheral protrusion 38d extending on the inner peripheral direction provided on the valve rubber holding portion 38b of the flow restricting body 38. The outer peripheral protrusion 36a is formed to provide a backlash (gap) with the inner peripheral wall 38e of the flow restricting body 38, and the inner peripheral protrusion 38d is formed to provide a backlash (gap) with the outer peripheral wall 36b of the moving body 36. Yes.

  Therefore, as shown in FIG. 6, when a substantially axial external force P is applied to the flow restricting body 38 in the valve opening direction, the flow restricting body 38 is inclined with respect to the moving body 36 or the rotor rotating shaft 34 by an angle θ, so-called. Swing motion occurs. Therefore, even when the actuator is installed to be inclined with respect to the valve seat of the fluid passage, the flow restricting body 38 freely swings so as to be adapted to the inclination of the valve seat, and a reliable valve closing can be realized.

  As described above, when there is an error in the mounting of the actuator to the fluid passage, for example, even when the actuator is inclined with respect to the valve seat, the flow restricting body can normally close the valve seat of the fluid passage by the swinging operation, which is reliable. It is possible to realize further improvement in reliability by performing the fluid control operation.

(Embodiment 7)
FIG. 7 is a sectional view of an actuator according to a seventh embodiment of the present invention. In the figure, the same members and the same functions as those in the embodiment of FIGS.

  A first bearing 51 is provided on the side surface 40b side of the partition wall 40 and supports the outer periphery of the rotor rotating shaft 34. The bearing 51 is housed and held in a bearing holding portion 52 formed integrally with the side surface portion 40b of the partition wall 40. ing. The bearing holding portion 52 is formed by providing an annular protrusion 40d on the side surface portion 40b and a recess 40e in the center by drawing. Reference numeral 53 denotes a second bearing provided on the attachment body 43 side and supporting the outer periphery of the rotor rotating shaft 34, and the bearing 53 is fixed to the attachment body 43. Here, the case where the rotor rotating shaft 34 is rotatably supported by the first bearing 51 and the second bearing 53 is shown, but the axial length of the first bearing 51 is increased to eliminate the second bearing 53. Can be cantilevered.

  For this reason, the bearing holding portion 52 can be formed without any misalignment with respect to the cylindrical portion 40a of the partition wall 40 by drawing, and the bearing 51 can be accurately placed at the center of rotation. Further, the partition wall 40 formed of an extremely thin plate can be reinforced by forming the projections and recesses of the annular projection 40d and the central recess 40e.

  In this way, since the bearing holding part is integrally formed with the partition wall, the gap between the rotor and the partition wall can be further reduced by high-precision processing without misalignment, and the strength of the partition wall can be improved by forming irregularities, so that the partition wall thickness is reduced. Further, the rotational force of the rotor can be further improved by reducing the magnetic gap between the stator and the rotor.

(Embodiment 8)
FIG. 8 is a sectional view of an actuator according to the eighth embodiment of the present invention. In the figure, the same members and the same functions as those in the embodiment of FIGS.

  A bearing body 54 receives a thrust load in the axial direction of the rotor rotating shaft 34 that is rotatably supported by the support shaft 41. The bearing body 54 is provided in contact with the outer peripheral portion of the rotor rotating shaft 34, and the through hole 43a and the rotor through which the rotor rotating shaft 34 is provided in the mounting body 43 to which the partition wall 40, the stator 32 and the rotation preventing body 37 are fixed. 30 is arranged so as to close the through hole 43a.

For this reason, when the back pressure is applied to the flow restricting body 38, an axial reaction force is applied to the mounting body 43 via the bearing body 54 as a thrust force when the flow restricting body 38 is pulled away from the valve seat 1. The bearing body 54 prevents the rotor 30 from coming into contact with the attachment body 43 and the like, and the friction loss is reduced by forming the bearing body 54 with a sliding material having a small frictional resistance. Furthermore, since the bearing body 54 is disposed so as to close the through hole 43a of the mounting body 43, dust, foreign matter, and the like can be prevented from entering the rotor 30 side from the fluid passage 3 side. Further, since the thrust bearing and the dust intrusion prevention lid can be used together in one, downsizing or productivity can be improved.

  As described above, the thrust load generated in the axial direction prevents the rotor from moving in the axial direction and comes into contact with a component such as a partition wall or an attachment body, and dust, foreign matter, etc. enter the rotor side from the fluid side. Can be maintained to maintain stable rotation and increase reliability, and further miniaturization or productivity can be improved.

Sectional drawing which shows the valve opening state of the actuator of Embodiment 1 and Embodiment 2 of this invention Sectional view showing the valve closed state of the actuator Sectional drawing of the actuator of Embodiment 3 and Embodiment 4 of this invention Sectional drawing of the actuator of Embodiment 5 of this invention Partial sectional view of an actuator according to Embodiment 6 of the present invention Sectional view showing the swing motion of the actuator Sectional drawing of the actuator of Embodiment 7 of this invention Sectional drawing of the actuator of Embodiment 8 of this invention Cross section of conventional actuator Sectional view of another conventional actuator

Explanation of symbols

DESCRIPTION OF SYMBOLS 30 Rotor 31 Magnetic pole 32 Stator 33 Excitation coil 34 Rotor rotating shaft 35 Feed means 36 Moving body 37 Anti-rotation body 38 Flow restricting body 39 Energizing body 40 Partition 41 Support shaft 42 Shaft hole 43 Attachment body 47 Shaft support body 49 Sealing Part 50 Locking part 51 Bearing 52 Bearing holding part 54 Bearing body

Claims (4)

A rotor having magnetic poles, a stator having an exciting coil, a rotor rotating shaft provided on the rotor, a feeding means provided on the rotor rotating shaft, a moving body screwed or engaged with the feeding means, and an axial direction A flow restricting body that is connected to the moving body so as to be movable in the axial direction through an urging body that urges the rotor, and is disposed on and integrated with a gap between the rotor and the stator and one end surface of the rotor. And a partition wall that hermetically separates the stator and the rotor on the fluid side, an attachment body to which the partition wall and the stator are attached, and a rotation prevention provided on the attachment body to restrict the rotation of the moving body An actuator comprising: a body; a first seal provided between the flange portion of the partition wall and the attachment body; and a second seal provided between the fluid and the attachment plate. The actuator according to claim 1, wherein the flow restricting body and the moving body are connected by a locking portion having a backlash in the radial direction so that the flow restricting body can swing freely. The actuator according to claim 1, further comprising: a bearing that supports an outer periphery of the rotor rotation shaft; and a bearing holding portion that is integrally formed with the partition wall, wherein the bearing is held by the bearing holding portion. The attachment body which fixed the partition, the stator, and the rotation prevention body, and the bearing body which receives the axial thrust load of a rotor rotating shaft were provided in any one of Claims 1-3 provided between the said attachment body and the rotor. The actuator described.

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