JP6163337B2 - Solenoid actuator - Google Patents

Description

  The present invention relates to a solenoid actuator.

  In Patent Document 1, a coil provided in a case, a sleeve provided on a case bottom side, a base provided on a case opening end side, a sleeve generated by a magnetic field generated by energizing the coil, A solenoid actuator is disclosed that includes a plunger that moves between the bases toward the case opening end.

JP 2010-135469 A

  The solenoid actuator described above generates a plunger suction force that moves the plunger to the base side (case opening end side) when the coil is energized. However, in a state where the end surface of the plunger is close to the sleeve, particularly in a state where the end surface of the plunger is in contact with the sleeve, the magnetic flux density between the end surface of the plunger and the sleeve is high. When the magnetic flux density at the plunger end surface is increased in this way, the force for attracting the plunger toward the sleeve is increased, and the plunger suction force is rapidly reduced.

  If the plunger movement control range (so-called control zone) includes a region where the plunger suction force decreases, plunger jumping or the like occurs in that region, and the operation of the plunger and the drive target device driven by the plunger There is a possibility that the operation of the drive unit becomes unstable.

  Therefore, the present invention has been made in view of the above problems, and an object thereof is to provide a solenoid actuator capable of stably operating a plunger.

The solenoid actuator of the present invention includes a case having one end formed as an open end, a coil provided in the case, and a first recess extending in the case axial direction, and is disposed on the bottom surface side of the case. A magnetic body, a second magnetic body that extends in the axial direction of the case and has a second concave portion that faces the first concave portion, and is disposed on the case opening end side; A plunger that moves between the first recess and the second recess toward the case opening end by a magnetic field generated by the operation, and an end surface of the plunger and the first recess when the coil is not energized. A regulating portion that regulates the proximity between the end surface of the plunger and the bottom surface of the first recess by forming a gap larger than a predetermined distance between the bottom surface and the predetermined distance, Come on when energized The distance between the end surface of the plunger and the bottom surface of the first recess at a position where a plunger suction force larger than a minimum plunger suction force in a control zone that is a movement control range of the plunger is generated. And

  According to the present invention, since the proximity of the end surface of the plunger and the bottom surface of the first recess is restricted by the restricting portion, the plunger does not come too close to the bottom surface of the first recess, and the plunger end surface on the bottom surface side of the first recess. It is possible to suppress the magnetic flux density from increasing, and it is possible to prevent a decrease in plunger attractive force. Accordingly, the plunger of the solenoid actuator can be stably operated.

1 is a perspective sectional view of an actuator device including a solenoid actuator according to a first embodiment of the present invention. It is a longitudinal cross-sectional view of an actuator apparatus. It is a figure which shows the characteristic of plunger stroke amount and plunger suction force. It is a longitudinal cross-sectional view of the actuator apparatus containing the solenoid actuator by 2nd Embodiment of this invention. It is a longitudinal cross-sectional view of the actuator apparatus containing the solenoid actuator by 3rd Embodiment of this invention.

(First embodiment)
Hereinafter, the actuator device 1 including the solenoid actuator 20 according to the first embodiment of the present invention will be described with reference to FIGS.

  As shown in FIGS. 1 and 2, the actuator device 1 includes a valve device 10 as a device to be driven and a solenoid actuator 20 that drives the valve device 10.

  The valve device 10 is a spool valve installed in a flow path through which hydraulic oil (working fluid) flows. The valve device 10 includes a cylindrical valve sleeve 11 and a spool 12 slidably provided in the valve sleeve 11. The valve sleeve 11 is configured as a housing that accommodates the spool 12 and is formed of aluminum. The spool 12 is configured as a drive unit that is driven by the solenoid actuator 20, and moves in the valve sleeve 11 in the sleeve axial direction.

  The valve device 10 is configured to adjust the flow rate of the hydraulic oil that flows through the valve sleeve 11 and flows into the flow path according to the position of the spool 12.

  As shown in FIG. 2, the solenoid actuator 20 includes a case 30 as an actuator case, a coil 41 wound around the bobbin 40, a sleeve 50 and a base 60 fitted into the inner peripheral surface 40 </ b> C of the bobbin 40, and a movable iron core. As a plunger 70. The solenoid actuator 20 is an electromagnetic actuator that moves the plunger 70 in the axial direction by a magnetic field generated by energizing the coil 41.

  The case 30 is a bottomed cylindrical member formed of a magnetic material (for example, iron), and is a housing frame that houses various members constituting the solenoid actuator 20. The front end of the case 30 is an open end 30A, and the open end 30A is configured as a caulking portion 31 for caulking and fixing one end of the valve sleeve 11 of the valve device 10.

  The bobbin 40 is a cylindrical member having flanges 40A and 40B at both ends. The bobbin 40 is made of an electrically insulating resin. The conductive wire wound around the outer peripheral surface of the bobbin body between the flanges 40A and 40B constitutes the coil 41. A terminal 42 that is electrically connected to the coil 41 is provided on the flange portion 40 </ b> A of the bobbin 40.

  The bobbin 40 is disposed in the case 30 in a state where the coil 41 is wound. In such a state, the terminal 42 of the bobbin 40 protrudes to the outside through the notch 32 of the case 30. By passing a current through the coil 41 via the terminal 42, a magnetic field is generated around the coil 41.

  Inside the bobbin 40, a sleeve 50 and a base 60 are installed as members constituting a magnetic path.

  The sleeve 50 is a cylindrical first magnetic body formed of a magnetic material (for example, iron). The sleeve 50 is press-fitted into the inner peripheral surface near the base end of the bobbin 40, and the base end surface of the sleeve 50 abuts against the bottom surface of the case 30 in such a press-fitted state.

  The base 60 is a cylindrical second magnetic body formed of a magnetic material (for example, iron). The base 60 is configured such that a base end portion thereof is press-fitted into an inner peripheral surface near the tip end of the bobbin 40. The base 60 and the sleeve 50 disposed inside the bobbin 40 are installed side by side in the axial direction. The base 60 is disposed on the opening end 30 </ b> A side in the case 30, and the sleeve 50 is disposed on the bottom surface side in the case 30.

  The base 60 and the sleeve 50 are connected by a cylindrical filler ring 21 formed of a nonmagnetic material. One end of the filler ring 21 is fitted into an annular recess 51 formed on the outer peripheral surface of the distal end of the sleeve 50, and the other end of the filler ring 21 is fitted into an annular recess 61 formed on the outer peripheral surface of the base end of the base 60. . By fixing the filler ring 21 in this manner, the sleeve 50 and the base 60 are separated in the axial direction, and a gap is formed between the distal end of the sleeve 50 and the proximal end of the base 60.

  At the tip of the base 60, a flange portion 64 that protrudes outward in the radial direction is formed. In a state where the base 60 is attached to the bobbin 40, the flange portion 64 of the base 60 and the flange portion 40A of the bobbin 40 face each other. A ring-shaped wave washer 22 is disposed between the flange portion 64 of the base 60 and the flange portion 40 </ b> A of the bobbin 40. The bobbin 40 is provided in the case 30 in a state in which the flange portion 40 </ b> B is urged by the wave washer 22 so as to contact the bottom surface of the case 30. Thereby, the play of the bobbin 40 in the case 30 in the case axial direction can be suppressed.

  The plunger 70 is a cylindrical member formed of a magnetic material (for example, iron). The plunger 70 is caulked and fixed to the outer peripheral surface of a shaft 71 formed of a nonmagnetic material (for example, stainless steel). As described above, by using the plunger 70 and the shaft 71 as separate members and caulking and fixing the plunger 70 to the shaft 71, it is possible to reduce variations in assembly as a plunger assembly.

  The shaft 71 passes through the plunger 70 in the axial direction through the through hole of the plunger 70. The shaft 71 projects from both end surfaces of the plunger 70 and extends in the axial direction. The shaft 71 is configured such that a tip surface thereof abuts on an end surface of the spool 12 of the valve device 10. The plunger 70 and the shaft 71 constituting the plunger assembly are movably disposed inside the sleeve 50 and the base 60.

  The inside of the sleeve 50 at the distal end side is formed as a circular hole-shaped first recess 53, and the inside of the sleeve 50 at the proximal end side is formed as a through hole 52 having a smaller diameter than the first recess 53. The 1st recessed part 53 and the through-hole 52 are extended in the case axial direction. One end of the through hole 52 opens to the base end surface (end surface on the case bottom side) of the sleeve 50, and the other end of the through hole 52 opens to the bottom surface of the first recess 53. The inner diameter of the first recess 53 is slightly larger than the outer diameter of the plunger 70, and the inner diameter of the through hole 52 is larger than the outer diameter of the shaft 71.

  On the other hand, the inside of the base end side of the base 60 is formed as a circular hole-like second recess 63, and the inside of the base 60 is formed as a through hole 62 having a smaller diameter than the second recess 63. The 2nd recessed part 63 and the through-hole 62 are extended in the case axial direction. The second recess 63 of the base 60 is provided to face the first recess 53 of the sleeve 50. One end of the through hole 62 opens on the tip end surface (end surface on the case opening end side) of the base 60, and the other end of the through hole 62 opens on the bottom surface of the second recess 63. The inner diameter of the second recess 63 is slightly larger than the outer diameter of the plunger 70, and the inner diameter of the through hole 62 is larger than the outer diameter of the shaft 71.

  The first recess 53 of the sleeve 50 and the second recess 63 of the base 60 form a plunger chamber 23 in which the plunger 70 fixed to the shaft 71 can move in the axial direction. The through holes 52 and 62 of the sleeve 50 and the base 60 respectively form shaft chambers 24 and 25 in which the shaft 71 can move in the axial direction.

  A bush 26 that slidably supports the plunger 70 is provided on the inner peripheral surface of the first recess 53 of the sleeve 50. The bush 26 is made of a nonmagnetic material. The inner diameter of the bush 26 is set slightly smaller than the inner diameters of the first recess 53 of the sleeve 50 and the second recess 63 of the base 60. By supporting the plunger 70 slidably via the bush 26, contact between the outer peripheral surface of the plunger 70 and the inner peripheral surfaces of the first recess 53 and the second recess 63 is prevented.

  A ring-shaped washer 27 is provided on the bottom surface of the second recess 63 of the base 60. The washer 27 is made of a nonmagnetic material. The washer 27 functions as a stopper member that defines the maximum drive position (maximum stroke amount) of the plunger 70.

  A plurality of communication grooves 70 </ b> A are formed on the outer peripheral surface of the plunger 70 along the axial direction to communicate the plunger chamber 23 on the base 60 side and the plunger chamber 23 on the sleeve 50 side. Therefore, the plunger chamber 23 and the shaft chambers 24 and 25 are always in communication with each other through the communication groove 70A. The base 60 and the sleeve 50 of the solenoid actuator 20 connected to the valve device 10 are filled with hydraulic oil, but the hydraulic oil in the plunger chamber 23 and the shaft chambers 24 and 25 moves in accordance with the movement of the plunger 70. The movement of the plunger 70 is not hindered by the hydraulic oil.

  The solenoid actuator 20 configured as described above is connected to the valve device 10. The valve sleeve 11 of the valve device 10 includes a flange portion 11 </ b> A at an end portion inserted into the case 30 of the solenoid actuator 20. The flange portion 11 </ b> A is formed so as to protrude radially outward from the end portion of the valve sleeve 11. 11 A of flange parts are formed as a taper-shaped protrusion which expands toward the base end side (base 60 side).

  The proximal end of the valve sleeve 11 including the flange portion 11 </ b> A is inserted into the case 30 through the open end 30 </ b> A of the case 30 of the solenoid actuator 20. The valve sleeve 11 is disposed such that the base end surface thereof is in contact with the front end surface of the base 60. The opening end 30A of the case 30 is configured as a caulking portion 31 that is caulked against the flange portion 11A of the valve sleeve 11 from the outside, and the caulking portion 31 is engaged so as to cover the tapered flange portion 11A. The valve device 10 and the solenoid actuator 20 are coupled to each other. The caulking portion 31 of the case 30 is formed by bending the opening end 30A of the case 30 inward.

  As described above, the flange portion 11A of the valve sleeve 11 and the caulking portion 31 of the case 30 constitute a connecting mechanism 80 that connects the valve sleeve 11 of the valve device 10 and the case 30 of the solenoid actuator 20 in the axial direction.

  In the actuator device 1, when no current is supplied to the coil 41 of the solenoid actuator 20, the shaft 71 is pushed rightward in FIG. 2 via the spool 12 biased by a spring (not shown), and one end of the shaft 71 is Stops in contact with the bottom surface of the case 30. At this time, the plunger 70 is located at the initial position in the plunger chamber 23 formed by the first recess 53 and the second recess 63.

  On the other hand, when a current is passed through the coil 41 of the solenoid actuator 20, a magnetic field is generated around the coil 41, and the plunger 70 moves in the case axial direction by this magnetic field. That is, the plunger 70 moves to the left in FIG. 2 toward the bottom surface of the second recess 63 between the first recess 53 of the sleeve 50 and the second recess 63 of the base 60. As the plunger 70 moves, the shaft 71 moves the spool 12 leftward. The spool 12 moves to a position where the plunger suction force and the biasing force of the spring that biases the spool 12 are balanced. By moving the spool 12 in this way, the flow rate of the hydraulic oil that flows through the valve sleeve 11 and flows into the flow path is adjusted. Note that the plunger suction force that moves the plunger 70 in the left direction can be controlled by adjusting the value of the current supplied to the coil 41.

  As described above, the solenoid actuator 20 generates a plunger suction force that moves the plunger 70 toward the opening end 30 </ b> A of the case 30 when the coil 41 is energized. As shown in FIG. 3, the plunger suction force changes according to the position (stroke amount) of the plunger 70 in the plunger chamber 23 even when the energization amount is constant. In FIG. 3, increasing the stroke amount means that the plunger 70 approaches the bottom surface of the second recess 63 of the base 60.

  Further, in the solenoid actuator 20, when the proximal end surface of the plunger 70 is close to the end surface of the first recess 53 of the sleeve 50, particularly when the proximal end surface of the plunger 70 is in contact with the bottom surface of the first recess 53. The magnetic flux density between the base end face of 70 and the bottom face of the first recess 53 is increased. When the magnetic flux density on the base end surface side of the plunger 70 is increased in this way, the force for attracting the plunger 70 toward the sleeve 50 is increased, and the plunger suction force is rapidly reduced as shown in the region A of FIG. End up.

  In order to prevent such a sudden decrease in the plunger suction force, the solenoid actuator 20 according to the present embodiment restricts the proximal end surface of the plunger 70 from being too close to the bottom surface of the first recess 53 of the sleeve 50.

  That is, as shown in FIG. 2, when the plunger 70 is in the initial position (non-energized position) in the plunger chamber 23, the shaft 71 formed of a nonmagnetic material (for example, stainless steel) is formed in the through hole of the sleeve 50. By contacting the bottom surface of the case 30 through 52, a gap is formed between the base end surface of the plunger 70 and the bottom surface of the first recess 53. As shown in FIG. 3, when the distance between the base end surface of the plunger 70 and the bottom surface of the first recess 53 becomes smaller than the distance d, the plunger suction force decreases, so the plunger 70 when the shaft 71 contacts the bottom surface of the case 30. The gap between the base end surface and the bottom surface of the first recess 53 is set to be larger than the distance d.

  Thus, in the solenoid actuator 20 of this embodiment, the non-magnetic shaft 71 connected to the plunger 70, the through hole 52 of the sleeve 50, and the bottom surface of the case 30 make the base end surface of the plunger 70 and the first recess. A restricting portion 100 that restricts proximity to the bottom surface of 53 is configured.

  The solenoid actuator 20 of the actuator device 1 according to the present embodiment described above has the following effects.

  The solenoid actuator 20 is configured such that the restriction portion 100 restricts the proximity of the end surface of the plunger 70 and the bottom surface of the first recess 53. That is, in the solenoid actuator 20, the nonmagnetic shaft 71 contacts the bottom surface of the case 30 through the through hole 52 of the sleeve 50, and a gap is formed between the base end surface of the plunger 70 and the bottom surface of the first recess 53. Thus, the proximity of the end surface of the plunger 70 and the bottom surface of the first recess 53 is restricted.

  As a result, the plunger 70 does not get too close to the bottom surface of the first recess 53 of the sleeve 50, the magnetic flux density on the base end surface side of the plunger 70 can be suppressed from increasing, and the plunger suction force can be prevented from decreasing. . Therefore, the plunger 70 and the spool 12 driven by the plunger 70 can be stably operated.

  Further, in a conventional solenoid actuator that does not have a restricting portion, not only the range where the plunger suction force decreases (region A in FIG. 3) is excluded from the control zone, but also the dimensional variation and assembly variation of the plunger assembly are taken into account. Thus, it is necessary to set the minimum stroke amount large as shown in the control zone B of FIG. As described above, in the conventional solenoid actuator, when the dimension variation of the plunger assembly is taken into consideration, the stroke area of the plunger closer to the bottom surface of the first recess cannot be effectively used.

  However, in the solenoid actuator 20 according to the present embodiment, since the proximity between the plunger 70 and the bottom surface of the first recess 53 is physically restricted by the restriction portion 100, the control in FIG. As shown in zone A, the minimum stroke amount can be set to a value immediately before the plunger suction force decreases. Therefore, in the solenoid actuator 20, the control zone can be expanded as compared with the conventional solenoid actuator.

  Furthermore, since the end surface of the plunger 70 does not contact the bottom surface of the first recess 53 of the sleeve 50, the end surface of the plunger 70 does not stick to the bottom surface of the first recess 53 via a thin oil film.

(Second Embodiment)
Next, the actuator device 1 including the solenoid actuator 20 according to the second embodiment will be described with reference to FIG. In FIG. 4, the same components as those in the first embodiment are denoted by the same reference numerals as those in the first embodiment.

  As shown in FIG. 4, in the solenoid actuator 20 according to the second embodiment, the plunger 90 is formed in a columnar shape instead of a cylindrical shape. On the outer peripheral surface of the plunger 90, a plurality of communication grooves 90 </ b> A are formed along the axial direction to communicate the plunger chamber 23 on the base 60 side and the plunger chamber 23 on the sleeve 50 side. Therefore, the plunger chamber 23 and the shaft chambers 24 and 25 are always in communication with each other through the communication groove 90A.

  A shaft 91 made of a non-magnetic material is connected to the distal end surface of the plunger 90. The shaft 91 is configured such that a tip surface thereof abuts on an end surface of the spool 12 of the valve device 10.

  In the solenoid actuator 20 of the second embodiment, a ring-shaped spacer 92 is used as the restricting portion 100 that restricts the proximity between the base end surface of the plunger 90 and the bottom surface of the first recess 53. It is arranged between the bottom surface of 53.

  The spacer 92 is formed of a non-magnetic material (for example, stainless steel) and is installed so as to contact the bottom surface of the first recess 53. The thickness of the spacer 92 is set so that the distance between the base end surface of the plunger 90 and the bottom surface of the first recess 53 is larger than the distance d when the plunger 90 abuts on the spacer 92.

  According to the solenoid actuator 20 according to the second embodiment, the plunger 90 abuts against the nonmagnetic spacer 92 provided in the first recess 53, so that the proximal end surface of the plunger 90 and the bottom surface of the first recess 53 are close to each other. Is regulated.

  Thereby, the plunger 90 does not come too close to the bottom surface of the first recess 53 of the sleeve 50, and a decrease in the plunger suction force can be prevented. Therefore, the plunger 90 and the spool 12 driven by the plunger 90 can be stably operated. Further, the control zone of the solenoid actuator 20 can be expanded as compared with the conventional solenoid actuator.

  Instead of providing the through hole 52 in the sleeve 50, a hole that is recessed in the bottom surface of the first recess 53 of the sleeve 50 is formed, and a nonmagnetic spacer 92 that can contact the base end surface of the plunger 90 is formed in this hole. It may be provided. In this case, the spacer 92 is formed in a block shape such as a cylinder, and the thickness of the spacer 92 is the distance between the base end surface of the plunger 90 and the bottom surface of the first recess 53 when the plunger 90 abuts against the spacer 92. It is set to be larger than d. Also in such a configuration, the proximity of the base end surface of the plunger 90 and the bottom surface of the first recess 53 is restricted by the plunger 90 coming into contact with the nonmagnetic spacer 92 provided in the first recess 53. The

(Third embodiment)
Next, the actuator device 1 including the solenoid actuator 20 according to the third embodiment will be described with reference to FIG. In FIG. 5, the same components as those in the first and second embodiments are denoted by the same reference numerals as those in the first and second embodiments.

  As shown in FIG. 5, in the solenoid actuator 20 according to the third embodiment, the plunger 90 is formed in a columnar shape, and a nonmagnetic shaft 91 is connected to the distal end surface of the plunger 90.

  In the solenoid actuator 20 of the third embodiment, a restriction shaft 93 is disposed on the bottom surface of the case 30 as the restriction portion 100 that restricts the proximity of the proximal end surface of the plunger 90 and the bottom surface of the first recess 53.

  The restriction shaft 93 is made of a non-magnetic material (for example, stainless steel) and extends in the case axial direction. The restriction shaft 93 is configured to protrude into the first recess 53 through the through hole 52 of the sleeve 50. The amount of protrusion of the restriction shaft 93 from the bottom surface of the first recess 53 is such that the distance between the base end surface of the plunger 90 and the bottom surface of the first recess 53 is larger than the distance d when the plunger 90 contacts the restriction shaft 93. Is set to be

  As described above, in the solenoid actuator 20, the restriction that restricts the proximity of the proximal end surface of the plunger 90 and the bottom surface of the first recess 53 by the restriction shaft 93 fixed to the bottom surface of the case 30 and the through hole 52 of the sleeve 50. The unit 100 is configured.

  According to the solenoid actuator 20 according to the third embodiment, the proximity of the base end surface of the plunger 90 and the bottom surface of the first recess 53 is restricted by the plunger 90 coming into contact with the nonmagnetic restriction shaft 93.

  Thereby, the plunger 90 does not come too close to the bottom surface of the first recess 53 of the sleeve 50, and a decrease in the plunger suction force can be prevented. Therefore, the plunger 90 and the spool 12 driven by the plunger 90 can be stably operated. Further, the control zone of the solenoid actuator 20 can be expanded as compared with the conventional solenoid actuator.

  The embodiment of the present invention has been described above. However, the above embodiment only shows a part of application examples of the present invention, and the technical scope of the present invention is limited to the specific configuration of the above embodiment. Absent.

  The actuator device 1 according to the first to third embodiments is configured to drive the spool 12 of the valve device 10 by the solenoid actuator 20. However, the actuator device 1 may be configured such that the drive unit of the drive target device other than the valve device 10 is driven by the solenoid actuator 20.

1 Actuator device 10 Valve device (device to be driven)
20 Solenoid actuator 30 Case 30A Open end 41 Coil 50 Sleeve (first magnetic body)
52 Through-hole 53 1st recessed part 60 Base (2nd magnetic body)
62 Through-hole 63 2nd recessed part 70 Plunger 71 Shaft 90 Plunger 91 Shaft 92 Spacer 93 Restriction shaft 100 Restriction part

Claims (4)

A case where one end is formed as an open end;
A coil provided in the case;
A first magnetic body having a first recess extending in the case axial direction and disposed on the bottom surface side of the case;
A second magnetic body that extends in the axial direction of the case and has a second recess provided to face the first recess, and is disposed on the case opening end side;
A plunger that moves between the first recess and the second recess toward the case opening end by a magnetic field generated by energizing the coil;
When the coil is not energized, a gap larger than a predetermined distance is formed between the end surface of the plunger and the bottom surface of the first recess , so that the end surface of the plunger and the bottom surface of the first recess are close to each other. and a regulating portion for regulating,
The predetermined distance is the end surface of the plunger and the bottom surface of the first recess at a position where a plunger suction force larger than a minimum plunger suction force in a control zone that is a movement control range of the plunger is generated when the coil is energized. The distance between
A solenoid actuator characterized by that . The regulation part is
A through hole formed in the first magnetic body so as to open to an end surface of the first magnetic body on a case bottom surface side and a bottom surface of the first recess;
A shaft formed of a non-magnetic material and extending in the axial direction from the plunger,
The shaft comes into contact with the bottom surface of the case through the through hole, and a gap is formed between the end surface of the plunger and the bottom surface of the first recess, so that the end surface of the plunger and the bottom surface of the first recess are close to each other. regulate,
The solenoid actuator according to claim 1. The regulation part is
A through hole formed in the first magnetic body so as to open to an end surface of the first magnetic body on a case bottom surface side and a bottom surface of the first recess;
A shaft formed of a nonmagnetic material and extending in the axial direction from the bottom surface of the case through the through hole, and
The end surface of the plunger abuts on the end surface of the shaft, and a gap is formed between the end surface of the plunger and the bottom surface of the first recess, so that the end surface of the plunger and the bottom surface of the first recess are close to each other. regulate,
The solenoid actuator according to claim 1. The restricting portion is a spacer formed of a nonmagnetic material and disposed in the first recess of the first magnetic material.
The solenoid actuator according to claim 1.

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