WO2017110814A1

WO2017110814A1 - Solenoid actuator

Info

Publication number: WO2017110814A1
Application number: PCT/JP2016/087964
Authority: WO
Inventors: 剛史弘中
Original assignee: Ｋｙｂ株式会社
Priority date: 2015-12-24
Filing date: 2016-12-20
Publication date: 2017-06-29
Also published as: JP2017117945A

Abstract

This solenoid actuator (20, 21) comprises: a coil (41); a base (50) which is excited by a magnetic force of the coil (41); a plunger (60) which is moved by an attractive force of the excited base (50); a biasing unit (70, 71) which, when the distance between the plunger (60) and the base (50) becomes equal to or less than a first predetermined value (L1), biases the plunger (60) in the direction opposite to the attractive force; and a restricting unit (70, 72) which, when the distance between the plunger (60) and the base (50) becomes equal to or less than a second predetermined value (L2) less than the first predetermined value (L1), restricts movement of the plunger (60).

Description

Solenoid actuator

The present invention relates to a solenoid actuator.

JP2014-194969A includes a cylindrical coil provided in a case, a magnetic body disposed on the inner peripheral side of the coil, a plunger that moves toward the magnetic body by a magnetic force generated by energizing the coil, A solenoid actuator is disclosed.

This solenoid actuator further includes a stopper member provided between the magnetic body and the plunger. The stopper member restricts the movement of the plunger and defines the maximum driving position of the plunger.

However, in the solenoid actuator described in JP2014-194969A, when a current is supplied to the coil and the plunger moves to the maximum driving position, an oil film is formed in the gap between the plunger and the stopper member, and the plunger and the stopper member are not attached. Arise. When the plunger sticks to the stopper member, the plunger is likely to stay at the maximum drive position even if the current supplied to the coil is reduced. For this reason, the hysteresis is increased in the region around the maximum drive position where the plunger and the stopper member are stuck, and it becomes difficult to control the position of the plunger by adjusting the current supplied to the coil.

Generally, since a region having a large hysteresis is excluded from the control region, the control region of the solenoid actuator is limited to a region excluding a region affected by the sticking between the plunger and the stopper member. When the control area of the solenoid actuator is limited in this way, the operating range of the valve element driven by the plunger is also limited, and thus the range in which the flow rate of the working fluid can be adjusted may be narrowed.

The object of the present invention is to expand the control area of the solenoid actuator.

According to an aspect of the present invention, the solenoid actuator includes a coil that generates a magnetic force according to a supplied current, a fixed core that is excited by the magnetic force of the coil, and a shaft that is attracted by the attracted force of the excited fixed core. When the distance between the movable iron core that moves in the direction and the movable iron core that faces in the axial direction and the fixed iron core is equal to or less than a first predetermined value, the movable iron core is moved in a direction opposite to the suction force. Movement of the movable iron core when the distance between the urging portion to be urged and the movable iron core facing the axial direction and the fixed iron core is equal to or smaller than a second predetermined value smaller than the first predetermined value. And a limiting unit for limiting.

FIG. 1 is a longitudinal sectional view of an actuator device including a solenoid actuator according to a first embodiment of the present invention. FIG. 2 is an enlarged view of the portion indicated by II in FIG. FIG. 3 is a plan view of the wave washer of the solenoid actuator according to the first embodiment of the present invention. 4 is a cross-sectional view taken along line IV-IV in FIG. FIG. 5 is a diagram showing the relationship between the stroke amount of the plunger of the solenoid actuator and the supply current value according to the first embodiment of the present invention. FIG. 6 is a diagram illustrating the relationship between the stroke amount of the plunger of the conventional solenoid actuator and the supply current value. FIG. 7 is an enlarged view of a solenoid actuator according to a second embodiment of the present invention corresponding to FIG.

(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 FIG. 1, the actuator device 1 includes a solenoid actuator 20 and a valve device 10 driven by the solenoid actuator 20.

The valve device 10 is a spool valve installed in a flow path through which a working fluid such as hydraulic oil flows. The valve device 10 includes a cylindrical valve sleeve 11 and a spool 12 slidably provided in the valve sleeve 11. The spool 12 is driven by the solenoid actuator 20 and moves in the valve sleeve 11 in the axial direction of the valve sleeve 11. A flow path (not shown) is connected to each side opening of the valve sleeve 11.

The valve device 10 adjusts the flow rate of the hydraulic oil flowing into the flow path through the valve sleeve 11 by changing the communication opening degree of the flow path according to the position of the spool 12.

The solenoid actuator 20 includes a coil 41 wound around the bobbin 40, a base 50 as a fixed iron core fitted on the inner peripheral side of the bobbin 40, a sleeve 52 connected to the base 50 via a nonmagnetic ring 51, A plunger 60 as a movable iron core slidably disposed in the sleeve 52, a spring 62 interposed between the base 50 and the plunger 60 in a compressed state, and a case 30 for housing them. Prepare. The solenoid actuator 20 is an electromagnetic actuator that excites the base 50 by a magnetic field generated by energizing the coil 41 and moves the plunger 60 in the axial direction by the attracting force of the excited base 50.

The case 30 is a bottomed cylindrical member formed of a magnetic material such as iron and accommodates various members constituting the solenoid actuator 20. The open end of the case 30 is configured as a caulking portion 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 at both ends, and is formed of an electrically insulating resin. A conductive wire wound around the outer peripheral surface of the bobbin body between the flanges constitutes the coil 41. A terminal 42 that is electrically connected to the coil 41 is provided on one flange of the bobbin 40.

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

The sleeve 52 is a cylindrical member formed of a magnetic material such as iron, and has a sliding hole 52a in which the plunger 60 is slidably accommodated. The base 50 is a columnar member formed of a magnetic material such as iron, and an accommodation recess 50a that can accommodate one end of the plunger 60, and an accommodation hole 50b that is formed coaxially with the accommodation recess 50a and accommodates the spring 62. Have.

The base 50 and the sleeve 52 are press-fitted inside the bobbin 40 along the axial direction. The base 50 is disposed on the bottom side in the case 30, and the sleeve 52 is disposed on the opening end side in the case 30.

The base 50 and the sleeve 52 are connected by a cylindrical nonmagnetic ring 51 formed of a nonmagnetic material. One end of the nonmagnetic ring 51 is fitted into an annular recess formed on the outer peripheral surface of the end portion of the sleeve 52, and the other end of the nonmagnetic ring 51 is fitted into an annular concave portion formed on the outer peripheral surface of the end portion of the base 50. The By fixing the nonmagnetic ring 51 in this manner, the sleeve 52 and the base 50 are separated from each other in the axial direction, and a gap is formed between the sleeve 52 and the base 50.

The plunger 60 is a cylindrical member formed of a magnetic material such as iron, and includes a through hole 60 a through which the shaft 61 is inserted, an outer peripheral surface 60 b slidably in contact with the inner peripheral surface of the sleeve 52, and an accommodation recess 50 a of the base 50. It has an end surface 60c facing the bottom surface 50c, and a plurality of communication grooves 60d formed in the outer peripheral surface 60b along the axial direction.

The base 50 and the sleeve 52 in which the plunger 60 is accommodated are filled with hydraulic oil. The oil chambers in the base 50 and the sleeve 52 partitioned by the plunger 60 are always communicated by the communication groove 60d. For this reason, the hydraulic oil in the base 50 and the sleeve 52 moves through the communication groove 60d in accordance with the movement of the plunger 60, and the movement of the plunger 60 is not hindered by the hydraulic oil.

The shaft 61 inserted through the through-hole 60a is a rod-like member formed of a non-magnetic material such as stainless steel, and the plunger 60 is caulked and fixed to the outer peripheral surface of the shaft 61. The shaft 61 penetrates the plunger 60 in the axial direction, and both end portions protrude from both end surfaces of the plunger 60. One end of the shaft 61 is coupled to the spool 12 of the valve device 10 by coupling means (not shown). At the other end of the shaft 61, a hook-shaped spring receiving portion 61a having an outer diameter larger than that of the through hole 60a is formed.

In the above configuration, the shaft 61 is fixed to the plunger 60. However, the present invention is not limited to this, and the shaft 61 may be inserted into the through hole 60a of the plunger 60 with play. In this case, in order to prevent the plunger 60 from coming out of the sleeve 52, a retaining portion is provided in the sliding hole 52 a of the sleeve 52.

The spring 62 is a coil spring that biases the plunger 60 in a direction opposite to the attractive force acting on the plunger 60 when the coil 41 is energized. One end of the spring 62 is locked to the spring receiving portion 61 a of the shaft 61, and the other end of the spring 62 is received and locked in the receiving hole 50 b of the base 50.

2, the solenoid actuator 20 further includes a wave washer 70 disposed on the bottom surface 50c of the housing recess 50a of the base 50 that faces the end surface 60c of the plunger 60.

As shown in FIG. 3, the wave washer 70 is an annular member, and is formed of a nonmagnetic material such as stainless steel or brass. The cross section in the circumferential direction of the wave washer 70 is formed in a wave shape having irregularities, as shown in FIG. The shape of the wave washer 70 is not limited to an annular shape, and may be a C-shape having a notch cut out in the radial direction.

As shown in FIG. 4, the axial length of the wave washer 70 is a natural length L1 when no external force is applied from the axial direction, and changes to a maximum compression length L2 when the external force is applied from the axial direction. The maximum compressed length L2 is substantially equal to the thickness of the wave washer 70.

Next, the operation of the actuator device 1 configured as described above will be described with reference to FIGS. FIG. 5 shows the relationship between the current value supplied to the coil 41 and the stroke amount of the plunger 60.

In the actuator device 1, when no current is supplied to the coil 41 of the solenoid actuator 20, the plunger 60 is biased in the direction of arrow A in FIG. At this time, the spool 12 comes into contact with a stopper portion provided on the valve sleeve 11, and the plunger 60 and the spool 12 are stopped at the initial position shown in FIG.

When a current exceeding a predetermined value is supplied to the coil 41 of the solenoid actuator 20, the base 50 is excited by the magnetic field generated around the coil 41, and the plunger 60 is pulled toward the base 50. That is, the plunger 60 moves in the direction of arrow B in FIG. As the plunger 60 moves, the spool 12 connected to the plunger 60 via the shaft 61 also moves. The spool 12 moves to a position where the force for attracting the plunger 60 and the biasing force of the spring 62 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. Since the force for attracting the plunger 60 varies depending on the current value supplied to the coil 41, the stroke amount of the plunger 60, that is, the position of the spool 12 is controlled by changing the current value supplied to the coil 41. Can do.

As shown in FIG. 5, when the current value supplied to the coil 41 gradually increases and the stroke amount of the plunger 60 reaches the first position S <b> 1, the plunger 60 comes into contact with the wave washer 70. In other words, when the stroke amount of the plunger 60 reaches the first position S1, the distance between the end surface 60c of the plunger 60 facing the axial direction and the bottom surface 50c of the base 50 is the first predetermined value of the wave washer 70. The natural length L1 is reached, and the end surface 60c of the plunger 60 comes into contact with the wave washer 70.

The wave washer 70 is gradually compressed by the plunger 60 as the plunger 60 is further drawn toward the base 50. The wave washer 70 is compressed to generate a biasing force that biases the plunger 60 in a direction opposite to the base 50.

When the current supplied to the coil 41 is further increased and the stroke amount of the plunger 60 reaches the second position S2, the movement of the plunger 60 is restricted by the wave washer 70. In other words, when the stroke amount of the plunger 60 reaches the second position S2, the distance between the end surface 60c of the plunger 60 and the bottom surface 50c of the base 50 is the maximum compression length of the wave washer 70 as a second predetermined value. L2 and the plunger 60 is restricted from moving further toward the base 50. That is, the maximum drive position of the plunger 60 is defined by the wave washer 70.

Thus, the plunger 60 and the base 50 are not in contact with each other, and the distance between the plunger 60 and the base 50 facing each other in the axial direction is kept in a state of being separated by a length L2 or more when the wave washer 70 is compressed. . Generally, in the region immediately before the plunger 60 and the base 50 come into contact, the suction force increases rapidly. In such a region, since the relationship between the current value supplied to the coil 41 and the stroke amount of the plunger 60 becomes unstable, it is necessary to exclude it from the control region. Therefore, the maximum compression length L2 of the wave washer 70, that is, the thickness of the wave washer 70, is set so as to limit the movement of the plunger 60 before the plunger 60 reaches the region where the suction force increases rapidly. The

When the stroke amount of the plunger 60 reaches the second position S2, that is, the maximum driving position, when the current supplied to the coil 41 is decreased, the force for attracting the plunger 60 toward the base 50 is also weakened. At this time, the wave washer 70 that has been compressed urges the plunger 60 in the direction opposite to the base 50. This urging force also acts as a restoring force for returning the shape of the wave washer 70 to a shape having a wavy cross section as shown in FIG.

In this manner, when the current supplied to the coil 41 is reduced after the plunger 60 reaches the maximum drive position, the plunger 60 is urged away from the wave washer 70 by the wave washer 70, and the wave washer 70. Returns to a shape with a wavy cross section. Therefore, even if the end surface 60 c of the plunger 60 is attracted to the wave washer 70 at the maximum drive position, the plunger 60 is immediately separated from the wave washer 70 by reducing the current supplied to the coil 41.

In general, the sliding frictional force between the plunger 60 and the sleeve 52 increases as the current supplied to the coil 41 increases, that is, as the magnetic field increases. The sliding frictional force acts as a static frictional force when the plunger 60 returns from the maximum driving position. For this reason, even if the current supplied to the coil 41 is decreased after the plunger 60 reaches the maximum drive position, a relatively large static frictional force acts on the plunger 60, so that the stroke amount of the plunger 60 is unlikely to decrease. Become.

On the other hand, in the solenoid actuator 20 according to the first embodiment, when the plunger 60 returns from the maximum drive position, the urging force of the wave washer 70 opposes the static friction force between the plunger 60 and the sleeve 52. Act on. For this reason, even after the plunger 60 reaches the maximum drive position, the stroke amount of the plunger 60 is likely to change according to the magnitude of the current supplied to the coil 41.

As described above, the wave washer 70 functions as an urging portion that urges the plunger 60 when the distance between the plunger 60 and the base 50 becomes equal to or less than the first predetermined value. It functions as a restricting unit that restricts the movement of the plunger 60 when the distance between them becomes equal to or smaller than a second predetermined value that is smaller than the first predetermined value.

And by providing the wave washer 70 between the plunger 60 and the base 50, the hysteresis caused by the plunger 60 sticking to the limiting portion can be eliminated, and the hysteresis due to the static frictional force can be reduced. . As a result, the control area of the solenoid actuator 20 can be expanded.

The solenoid actuator 20 of the actuator device 1 according to the first embodiment has the following effects.

The solenoid actuator 20 functions as a biasing portion that biases the plunger 60 in a direction opposite to the suction force when the distance between the plunger 60 and the base 50 facing each other in the axial direction becomes equal to or less than a first predetermined value. And a wave washer that functions as a restricting portion that restricts movement of the plunger 60 when the distance between the plunger 60 and the base 50 facing in the axial direction becomes equal to or smaller than a second predetermined value smaller than the first predetermined value. 70.

By providing the wave washer 70 having the above function, the plunger 60 is prevented from sticking to the restricting portion, and the hysteresis caused by the plunger 60 sticking can be eliminated. As a result, the control area of the solenoid actuator 20 can be expanded.

On the other hand, in the conventional solenoid actuator not provided with the pressing portion, if the plunger is attracted to the stopper member that restricts the movement of the plunger, the plunger stays at the maximum drive position even if the force for sucking the plunger is reduced. It will be. This case will be specifically described with reference to FIG.

As shown in FIG. 6, when the current supplied to the coil increases and the plunger stroke reaches the maximum drive position Smax, the plunger sticks to the stopper member that defines the maximum drive position Smax. Even if the current supplied to the coil is decreased, the plunger remains at the maximum drive position Smax.

As described above, the hysteresis is increased in the region where the stopper member and the plunger stick to each other. Since the stroke amount of the plunger cannot be accurately controlled in a region where the hysteresis is large, the conventional solenoid actuator has a narrow control region.

On the other hand, in the solenoid actuator 20 according to the present embodiment, as shown in FIG. 5, the plunger 60 does not stick, so that the stroke range of the controllable plunger 60 can be expanded to the maximum drive position Smax. .

Hereinafter, modified examples of the solenoid actuator 20 according to the first embodiment will be described.

In the solenoid actuator 20, the wave washer 70 is disposed on the bottom surface 50c of the housing recess 50a of the base 50. Alternatively, the wave washer 70 may be disposed on the end surface 60c of the plunger 60, or when the distance between the axially opposed plunger 60 and the base 50 becomes equal to or less than the first predetermined value. As long as 60 can be urged in the direction opposite to the suction force, it may be arranged at any position.

In the solenoid actuator 20, one wave washer 70 is provided. Instead of this, a plurality of wave washers 70 may be provided.

In the solenoid actuator 20, the wave washer 70 is employed as a member that functions as an urging portion and a limiting portion. Instead of this, a coil spring or a disc spring formed of a non-magnetic material, or an elastic ring formed of rubber or resin may be employed as a member that functions as an urging portion and a limiting portion. In this case, the natural length of the coil spring or the disc spring is set to be the natural length L1 of the wave washer 70, and the length when the coil spring is in close contact and the axial length of the disc spring at the maximum compression are set as the wave washer. The maximum compression length L2 is set to 70. The axial length of the elastic ring when no external force is applied from the axial direction is set to be the natural length L1 of the wave washer 70, and the axial length of the elastic ring at the time of maximum compression is the wave washer. The maximum compression length L2 is set to 70.

(Second Embodiment)
Next, the actuator device 1 including the solenoid actuator 21 according to the second embodiment will be described with reference to FIG. FIG. 7 shows a portion corresponding to FIG. 2. In FIG. 7, the same reference numerals as those in the first embodiment are given to the same components as those in the first embodiment.

As shown in FIG. 7, in the solenoid actuator 21 according to the second embodiment, instead of the wave washer 70, an elastic ring 71 that functions as an urging portion and a washer 72 that functions as a restricting portion are included in the housing recess 50a. Arranged on the bottom surface 50c.

The elastic ring 71 is an annular member that is formed of rubber, resin, or the like and has an axial length L3 in a state where no external force is applied from the axial direction. The elastic ring 71 is deformed when the end surface 60c of the plunger 60 comes into contact therewith, and generates a restoring force. The restoring force acts on the plunger 60 as a biasing force that biases the plunger 60 in a direction opposite to the suction force. The cross-sectional shape of the elastic ring 71 is not limited to a circle, and may be an ellipse, a rectangle, or an X shape.

The washer 72 is an annular plate member formed of a nonmagnetic material such as stainless steel or brass, and is disposed inside the elastic ring 71. The axial length L4 of the washer 72, that is, the thickness of the washer 72, is set so as to limit the movement of the plunger 60 before the plunger 60 reaches the region where the suction force suddenly increases.

The axial length L3 of the elastic ring 71 corresponds to the natural length L1 of the wave washer 70 in the first embodiment, and the axial length L4 of the washer 72 is the maximum compression length L2 of the wave washer 70. It corresponds to.

Next, the operation of the actuator device 1 including the solenoid actuator 21 will be described with reference to FIGS.

When a predetermined current or more is supplied to the coil 41 of the solenoid actuator 21, the base 50 is excited by the magnetic field generated around the coil 41, and the plunger 60 is pulled toward the base 50. The spool 12 connected to the plunger 60 via the shaft 61 moves to a position where the force for attracting the plunger 60 and the biasing force of the spring 62 are balanced. As described above, in the actuator device 1, similarly to the actuator device 1 including the solenoid actuator 20 according to the first embodiment, the flow rate of the working oil that flows into the flow path through the valve sleeve 11 by the movement of the spool 12. Is adjusted.

As shown in FIG. 5, when the current value supplied to the coil 41 gradually increases and the stroke amount of the plunger 60 reaches the first position S1, the plunger 60 comes into contact with the elastic ring 71. In other words, when the stroke amount of the plunger 60 reaches the first position S1, the distance between the end surface 60c of the plunger 60 facing the axial direction and the bottom surface 50c of the base 50 is the first predetermined value of the elastic ring 71. The length in the axial direction is L 3, and the end surface 60 c of the plunger 60 comes into contact with the elastic ring 71.

The elastic ring 71 is gradually compressed by the plunger 60 as the plunger 60 is further pulled toward the base 50. The elastic ring 71 is compressed to generate a biasing force that biases the plunger 60 in a direction opposite to the base 50.

When the current supplied to the coil 41 is further increased and the stroke amount of the plunger 60 reaches the second position S2, the movement of the plunger 60 is limited by the washer 72. In other words, when the stroke amount of the plunger 60 reaches the second position S2, the distance between the end surface 60c of the plunger 60 and the bottom surface 50c of the base 50 becomes the axial length L4 of the washer 72 as the second predetermined value. The plunger 60 is restricted from moving further toward the base 50. That is, the maximum drive position of the plunger 60 is defined by the washer 72.

Thus, the plunger 60 and the base 50 are not in contact with each other, and the distance between the plunger 60 and the base 50 facing each other in the axial direction is kept at a distance apart from the axial length L4 of the washer 72.

When the stroke amount of the plunger 60 reaches the second position S2, that is, the maximum driving position, when the current supplied to the coil 41 is decreased, the force for attracting the plunger 60 toward the base 50 is also weakened. At this time, the compressed elastic ring 71 urges the plunger 60 in a direction opposite to the base 50.

Thus, when the current supplied to the coil 41 is reduced after the plunger 60 reaches the maximum drive position, the plunger 60 is urged away from the washer 72 by the elastic ring 71. For this reason, even if the end surface 60 c of the plunger 60 is attracted to the washer 72 at the maximum drive position, the plunger 60 is immediately separated from the washer 72 by reducing the current supplied to the coil 41.

Further, in the solenoid actuator 21 according to the second embodiment, as with the solenoid actuator 20 according to the first embodiment, when the plunger 60 returns from the maximum drive position, the urging force of the elastic ring 71 is applied to the plunger 60 and the sleeve 52. It acts so as to oppose the static friction force between the two. For this reason, even after the plunger 60 reaches the maximum drive position, the stroke amount of the plunger 60 is likely to change according to the magnitude of the current supplied to the coil 41.

Thus, the elastic ring 71 functions as an urging portion that urges the plunger 60 when the distance between the plunger 60 and the base 50 is equal to or less than the first predetermined value, and the washer 72 When the distance to the base 50 becomes equal to or smaller than a second predetermined value that is smaller than the first predetermined value, it functions as a limiting unit that limits the movement of the plunger 60.

By providing the elastic ring 71 and the washer 72 between the plunger 60 and the base 50, the hysteresis caused by the plunger 60 sticking to the restricting portion can be eliminated, and the hysteresis caused by the static frictional force can be reduced. it can. As a result, the control area of the solenoid actuator 21 can be expanded.

According to the above second embodiment, the following effects are obtained.

The solenoid actuator 21 functions as an urging unit that urges the plunger 60 in a direction opposite to the suction force when the distance between the axially opposed plunger 60 and the base 50 is equal to or less than a first predetermined value. Functioning as a restricting portion that restricts movement of the plunger 60 when the distance between the elastic ring 71 and the axially opposed plunger 60 and the base 50 is equal to or smaller than a second predetermined value smaller than the first predetermined value. And a washer 72.

Since the elastic ring 71 is provided, the plunger 60 is prevented from sticking to the washer 72, and the hysteresis caused by the plunger 60 sticking can be eliminated. As a result, the control area of the solenoid actuator 21 can be expanded.

Hereinafter, modified examples of the solenoid actuator 21 according to the second embodiment of the present invention will be described.

In the solenoid actuator 21, the elastic ring 71 and the washer 72 are disposed on the bottom surface 50 c of the housing recess 50 a of the base 50. Instead of this, either one or both of them may be disposed on the end surface 60 c of the plunger 60. If the elastic ring 71 can urge the plunger 60 in a direction opposite to the suction force when the distance between the plunger 60 and the base 50 facing in the axial direction becomes equal to or less than the first predetermined value. It may be arranged at any position. Further, the washer 72 is disposed at any position as long as the movement of the plunger 60 can be restricted when the distance between the plunger 60 and the base 50 becomes equal to or smaller than a second predetermined value smaller than the first predetermined value. May be.

In the solenoid actuator 21, the elastic ring 71 and the washer 72 are disposed on the same plane. Instead, an accommodation groove for accommodating the washer 72 disposed inside the elastic ring 71 may be formed in the bottom surface 50c. In this case, since the washer 72 is disposed in the receiving groove, the movement of the washer 72 in the radial direction is restricted. The elastic ring 71 may be disposed inside the washer 72, and a receiving groove for receiving the elastic ring 71 may be formed on the bottom surface 50c.

Further, in the solenoid actuator 21, an elastic ring 71 is adopted as an urging portion. Instead of this, a coil spring or a disc spring formed of a non-magnetic material may be employed as the urging portion.

Hereinafter, the configuration, operation, and effect of the embodiment of the present invention will be described together.

The

solenoid actuators

20 and 21 include a coil 41 that generates a magnetic force according to a supplied current, a base 50 that is excited by the magnetic force of the coil 41, and a plunger 60 that moves in the axial direction by the attractive force of the excited base 50. And biasing

portions

70 and 71 for biasing the plunger 60 in the direction opposite to the suction force when the distance between the axially facing plunger 60 and the base 50 is equal to or less than the first predetermined value L1; Limiting

portions

70 and 72 for restricting movement of the plunger 60 when the distance between the axially facing plunger 60 and the base 50 is equal to or smaller than a second predetermined value L2 smaller than the first predetermined value L1, Is provided.

In this configuration, when the distance between the plunger 60 and the base 50 facing in the axial direction becomes equal to or less than the first predetermined value L1, the plunger 60 is moved in the direction opposite to the suction force by the urging

portions

70 and 71. When the distance between the urged and axially opposed plunger 60 and the base 50 becomes equal to or smaller than a second predetermined value L2 that is smaller than the first predetermined value L1, the movement of the plunger 60 is limited by the limiting

portions

70 and 72. Limited by. As described above, the provision of the urging

portions

70 and 71 suppresses the plunger 60 from sticking to the limiting

portions

70 and 72, and the hysteresis caused by the plunger 60 sticking is eliminated. As a result, the control area of the

solenoid actuators

20 and 21 can be expanded. Further, since the controllable stroke range is expanded, it is not necessary to enlarge the

solenoid actuators

20 and 21 in order to ensure the stroke amount. For this reason, the

solenoid actuators

20 and 21 can be miniaturized, and the manufacturing cost can be reduced.

Further, the urging

portions

70 and 71 and the restricting

portions

70 and 72 are disposed between the plunger 60 and the base 50 facing in the axial direction.

In this configuration, the urging

portions

70 and 71 and the restricting

portions

70 and 72 are disposed between the plunger 60 and the base 50 facing in the axial direction. Thus, since the plunger 60 and the base 50 do not contact directly, it can prevent that the plunger 60 and the base 50 are damaged by a collision. Further, since the impact when the plunger 60 approaches the base 50 is absorbed by the urging

portions

70 and 71, the operating noise of the

solenoid actuators

20 and 21 can be reduced.

Further, the urging unit 70 and the limiting unit 70 are integrally formed.

In this configuration, the urging unit 70 and the limiting unit 70 are integrally formed. Since it is not necessary to form the urging portion 70 and the limiting portion 70 separately, the number of parts can be reduced, the manufacturing cost of the solenoid actuator 20 can be reduced, and the assemblability can be improved.

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.

For example, the

solenoid actuators

20 and 21 are of a so-called pull type that displaces the spool 12 toward the coil 41 by energizing the coil 41. Instead of this, the solenoid actuator may be a so-called push type that displaces the spool 12 to the opposite side to the coil 41 by energizing the coil 41.

Further, the

solenoid actuators

20 and 21 drive the spool 12 connected to the plunger 60. Instead of this, the

solenoid actuators

20 and 21 may drive the poppet valve by the plunger 60. The valve element driven by the plunger 60 may be any type of valve element as long as it adjusts the opening of the flow path.

This application claims priority based on Japanese Patent Application No. 2015-252141 filed with the Japan Patent Office on December 24, 2015, the entire contents of which are incorporated herein by reference.

Claims

A solenoid actuator,
A coil that generates a magnetic force according to the supplied current;
A fixed iron core excited by the magnetic force of the coil;
A movable core that moves in the axial direction by the attractive force of the magnetized fixed core;
A biasing portion that biases the movable core in a direction opposite to the suction force when a distance between the movable core facing the axial direction and the fixed core is equal to or less than a first predetermined value;
A limiting unit that restricts movement of the movable core when a distance between the movable core and the fixed core facing each other in the axial direction is equal to or smaller than a second predetermined value that is smaller than the first predetermined value; Solenoid actuator provided.
The solenoid actuator according to claim 1,
The urging portion and the restricting portion are solenoid actuators arranged between the movable iron core and the fixed iron core facing in the axial direction.
The solenoid actuator according to claim 1,
The biasing portion and the limiting portion are solenoid actuators that are integrally formed.