JP2014062608A - Solenoid valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solenoid valve that suppresses generation of noise and has an enhanced durability.SOLUTION: In a solenoid valve 100, a valve body 110 includes a coupling part 113 to which a plunger tube 120 is coupled, a valve chest 115, and a valve seat 105a. First and second plungers 130, 140, which are movable in up and down direction, are arranged in the plunger tube, and first and second coils 121, 126 are arranged at a periphery of the plunger tube. The first plunger passes through a center through-hole 145 formed in the second plunger and is arranged to be movable in the up and down direction, and has a valve body 135 for opening/closing the valve seat at its lower end. The second plunger passes through a communication hole 114 formed in the coupling part and is arranged to be movable in the up and down direction. The valve body is movable to a fist position which is a position where the solenoid valve is completely closed, a second position which is a position where the solenoid valve is slightly opened, and a third position which is a position where the solenoid valve is fully opened.

Description

  The present invention relates to a solenoid valve used for opening and closing a flow path in a system for controlling the flow of fluid.

  Conventionally, electromagnetic valves have been used as on-off valves. The electromagnetic valve includes a plunger formed integrally with the valve body and an electromagnet that drives the plunger with a magnetic force. In addition, electromagnetic valves have been used as proportional control valves for controlling the flow rate and pressure of fluid. Proportional solenoid valves, for example, use a pulse width modulation (PWM) drive system that supplies a pulsed voltage with a fixed period to adjust the ratio of on time to off time (duty ratio) to the coil of the proportional solenoid valve. The opening degree is adjusted by opening and closing.

Japanese Patent Application Laid-Open No. 10-0778155 Japanese Patent No. 3095892

  However, as disclosed in Patent Document 1, the electromagnetic valve has a very large number of opening and closing operations, and the valve body and the valve seat collide with each other, so that the valve seat and the valve body are worn, and fluid leakage and accurate control are performed at an early stage. Not only is there a problem in durability, such as the inability to perform the operation, but there are also problems such as the occurrence of noise due to the collision between the valve body and the valve seat.

  In view of such problems, an object of the present invention is to provide an electromagnetic valve that suppresses the generation of noise and improves durability.

  In order to achieve the above object, a solenoid valve according to the present invention includes a valve main body, a plunger tube, a first and a second plunger movable in the plunger tube, and the first and second plungers independently. An electromagnetic valve having at least first and second coils to be excited and an attractor capable of attracting the excited first and second plungers, wherein the valve body is connected to a plunger tube, and the first and second coils are connected to each other. A connecting portion through which the two plungers penetrate, a valve chamber communicating with the inlet-side fluid passage and the outlet-side fluid passage, and a valve seat provided in the valve chamber between the inlet-side fluid passage and the outlet-side fluid passage. The plunger tube is provided with first and second plungers that can move independently in the vertical direction, Around the tube, first and second coils are provided corresponding to the first and second plungers, respectively, and the first plunger further passes through a central through hole formed in the second plunger. A valve body is provided that is movable in the vertical direction, and at the lower end thereof can be seated or separated from the valve seat and can open and close the valve seat. The second plunger is further connected to the valve body. The valve body provided in the first plunger is movable in the vertical direction through the communication hole formed in the portion, and is located at the position where the electromagnetic valve is completely closed by being seated on the valve seat. 1 position, moved upward by moving away from the valve seat, the second position, which is a position where the solenoid valve is slightly opened, and moved further sufficiently upward from the valve seat, and the solenoid valve is fully opened It is possible to move to a third position that is a position To.

  By configuring the solenoid valve in this way, it is possible to select a slightly open position where the solenoid valve does not completely close. Therefore, the frequency with which the valve body constituting the solenoid valve contacts the valve seat is reduced. The wear of the body and the valve seat is reduced, and the generation of noise due to the contact between the valve body and the valve seat is suppressed. Furthermore, it is possible to suppress the water hammer phenomenon caused by the complete closing of the solenoid valve. As a result, the durability of the solenoid valve can be improved.

FIG. 3 is a vertical sectional view of the electromagnetic valve according to the first embodiment of the present invention when the electromagnetic valve is in a fully closed position as a first position. It is a vertical sectional view when the solenoid valve of FIG. 1 is in the slightly open position as the second position. It is a vertical sectional view when the solenoid valve of FIG. 1 is in a fully open position as a third position. It is a solenoid valve concerning a 2nd embodiment of the present invention, Comprising: It is a vertical sectional view when this solenoid valve exists in a fully closed position as the 1st position. FIG. 5 is a vertical cross-sectional view when the solenoid valve of FIG. 4 is in a slightly open position as a second position. FIG. 5 is a vertical sectional view when the solenoid valve of FIG. 4 is in a fully open position as a third position.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

  1-3 show vertical sectional views in which the electromagnetic valve according to the first embodiment of the present invention is in the first to third positions, respectively. As shown in FIG. 1, the electromagnetic valve 100 generally includes a valve body 110, a plunger tube 120, first and second plungers 130 and 140, first and second coils 121 and 126, an attractor 150, a first one. First and second coil springs 139 and 149 are provided. As shown in FIGS. 1 to 3, these components constituting the electromagnetic valve 100 are assembled concentrically with the axis O-O ′ as a common center line.

In the present embodiment, the valve main body 110 includes a housing portion 111 having a valve chamber 115 formed as a cylindrical space having a circular horizontal section inside, and a lid portion 112 that closes the valve chamber 115 above the housing portion 111. I have. The lid part 112 is fixed to the housing part 111 by screwing or the like. The lid portion 112 is also provided with a cylindrical coupling portion 113 to which the plunger tube 120 is coupled, and a communication hole 114 is formed in the coupling portion 113 so as to penetrate the entire lid portion 112 up and down. . The communication hole 114 formed in the connecting portion 113 of the lid portion 112 has a circular horizontal cross section. In the present embodiment, first and second plungers 130 and 140 described later pass through the communication hole 114 and extend into the valve chamber 115. The first and second plungers 130 and 140 are concentrically arranged along the axis OO ′ in the communication hole 114 and the valve chamber 115, and are attached to be movable in the vertical direction independently of each other. . In the present embodiment, a stepped portion 112 a is formed on the lower surface of the lid portion 112 between the communication hole 114 and the valve chamber 115 so as to face downward. Specifically, the horizontal cross-sectional diameter circle (inside diameter) _{d 1} of the communication hole 114 is designed to be smaller than the horizontal cross-sectional diameter circle (inside diameter) _{d 2} of the valve chamber 115 (d1 <d2). By forming the stepped portion 112a on the lower surface of the lid portion 112 in this way, the stepped portion 143a of the second plunger 140 abuts on the stepped portion 112a formed on the lid portion 112, as will be described later, and the second portion The plunger 140 is restricted from rising.

  In the present embodiment, the valve chamber 115 is opened upward and closed by the lid portion 112 as described above. The valve chamber 115 is also opened downward so as to communicate with an outlet side fluid passage formed in the second joint 106, and further, an inlet side formed in the first joint 108. It opens to the side so as to communicate with the fluid passage. A seat member 105 is disposed between the second joint 106 and the valve chamber 115. The seat member 105 has a substantially cylindrical shape, and a flow passage 107 penetrating vertically is formed. A valve seat 105a is formed at an upper end portion, and a flange 105b surrounding the lower end surface opening portion is formed at a lower end portion. Is formed. The seat member 105 and the first and second joints 108 and 106 can be fixed to the casing 111 of the valve body 110 by, for example, brazing. The valve seat 105 a formed at the upper end opening of the seat member 105 is configured such that a spherical valve body 135 attached to the lower end of the first plunger 130 can be seated. In the present embodiment, the fluid flows from the first joint 108 in which the inlet-side fluid passage is formed to the second joint 106 in which the outlet-side fluid passage is formed. However, the flow of the fluid is not limited to this, and may flow from the fluid passage of the second joint to the fluid passage of the first joint.

  As shown in FIG. 1, when the valve body 135 is seated on the valve seat 105a and the flow of fluid from the first joint 108 to the second joint 106 is interrupted, the solenoid valve 100 is The position is in the fully closed position. In this embodiment, the valve body 135 is formed in a spherical shape, but the valve body 135 is not limited to a spherical shape, and is seated (lowered) or separated (raised) from the valve seat 105a. Thus, any shape may be used as long as the fluid flow can be opened and closed.

The plunger tube 120 has a hollow cylindrical shape, extends above the valve main body 110, and is attached to the valve main body 110 via a lid portion 112 at a lower portion thereof. It is attached. That is, the cylindrical plunger tube 120 has a configuration in which the upper end is closed by the suction element 150 and the lower end is closed by the valve body 110. In the present embodiment, the inside diameter _{d 3} of the plunger tube 120 is substantially equal to the outer diameter of the connecting portion 113 of the lid 112 (diameter).

  In the present embodiment, the solenoid valve 100 includes first and second plungers 130 and 140 as two movable iron cores, and a first coil 121 and second solenoid coils as two solenoid coils that drive the two movable iron cores. Two coils 126 are provided.

  In the plunger tube 120, first and second plungers 130 and 140 as two movable iron cores are accommodated so as to be movable in the vertical direction along the axis O-O '. The first and second plungers 130 and 140 are excited and de-energized independently by turning on and off the first coil 121 and the second coil 126, respectively. As a result, the first and second plungers 130 and 140 are independently attracted to the attracting element 150 or are urged downward by the respective coil springs 139 and 149 so as to be independently vertically moved. Can move in the direction.

  In the present embodiment, the first plunger 130 is roughly mounted in a cylindrical body 131, a spring receiving portion 132, a cylindrical small diameter portion 133, and a recess 134 formed at the lower end of the cylindrical small diameter portion 133. A valve body 135 and a first coil spring 139 are provided.

The outer diameter (diameter) D ₁ of the cylindrical main body 131 of the first plunger 130 is substantially equal to the inner diameter d ₃ of the plunger tube 120 (D ₁ ≈d ₃ ). As shown in FIG. 1, the columnar main body 131 is formed to be movable in the vertical direction along the axis OO ′ within the cylindrical plunger tube 120. Since the columnar main body 131 of the first plunger 130 is formed to be movable in the vertical direction within the plunger tube 120, the valve body 135 attached to the lower end of the columnar small diameter portion 133 of the first plunger 130 is a valve. The seat 105a is opened and closed.

Cylindrical small diameter portion 133 of the first plunger 130 is smaller than the outer diameter (diameter) _{D 1} of the cylindrical body 131, and outer diameter substantially equal to the inner diameter _{d 4} of the central through hole 145 of the second plunger 140 to be described later (Diameter) D ₂ (D ₁ > D ₂ ≈d ₄ ). With this configuration, the cylindrical small-diameter portion 133 of the first plunger 130 passes through the center through hole 145 of the second plunger 140, and the center through hole 145 has an axis OO ′. It can move independently in the vertical direction along. Accordingly, the first plunger 130 and the second plunger 140 are movable in the vertical direction along the axis OO ′.

A first coil spring 139 is provided between the cylindrical main body 131 of the first plunger 130 and the suction element 150 provided at the upper end of the plunger tube 120, and the first plunger 130 is attached facing downward. It is fast. Thereby, as shown in FIG. 1, the valve body 135 attached to the lower end of the first plunger 130 is seated on the valve seat 105a to block the flow of fluid. When the solenoid valve 100 is in the first position, which is the fully closed position, a first gap L ₁ is formed between the lower surface of the attractor 150 and the upper surface of the columnar body 131 of the first plunger 130. It is formed. One end of the first coil spring 139 is supported by the suction element 150, and the other end is held in a recess 137 provided in the columnar body 131.

A spring receiving portion 132 is formed at the lower end of the cylindrical main body 131 so as to support the other end of the second coil spring 149 interposed between the first plunger 130 and the second plunger 140. The spring receiving portion 132 is preferably formed of a buffer member such as PTFE (polytetrafluoroethylene), for example, so as to reduce the impact of the first and second plungers 130 and 140 colliding with each other. Note that one end of the second coil spring 149 is held in a recess 147 provided in the cylindrical main body 141 of the second plunger 140. As shown in FIG. 1, when the electromagnetic valve 100 is in the first position of the fully closed position, the second plunger 140 is urged downward by the second coil spring 149. At this time, the distance between the lower surface of the spring receiving portion 132 of the first plunger 130 and the upper surface of the cylindrical main body 141 of the second plunger 140 is designed to have a _second gap L2.

  In the present embodiment, the second plunger 140 generally includes a cylindrical main body 141, a cylindrical small diameter portion 142, a flange portion 143 provided at the lower end of the cylindrical small diameter portion 142, and a second coil spring 149. The second plunger 140 is formed with a central through hole 145 that penetrates from the upper cylindrical body 141 to the lower flange portion 143. In FIG. 1, the cylindrical main body 141 is formed so as to be movable in the vertical direction along the axis O-O ′ in the plunger tube 120. In the present embodiment, the cylindrical small diameter portion 142 including the flange portion 143 is integrally connected to the cylindrical main body 141 by, for example, welding, brazing, screw connection, or the like.

Incidentally, the cylindrical body 141, since that can move the plunger tube 120, an outer diameter (diameter) _{D 3} of the cylindrical body 141 is substantially equal to the inside diameter _{d 3} of the plunger tube 120 _{(D 1} ≒ _{D 3} ≈d ₃ ). Further, the outer diameter (diameter) D ₄ of the cylindrical small-diameter portion 142 is smaller than the outer diameter (diameter) D ₃ of the cylindrical main body 141 (D ₄ <D ₃ ), so that the cylindrical main body 141 and the cylindrical small-diameter portion 142 are the same. A stepped portion 141a is formed between the two. The cylindrical small-diameter portion 142 is configured to be able to move in the vertical direction along the axis OO ′ within the communication hole 114 formed in the connecting portion 113 of the lid portion 112 of the valve body 110. Therefore, the outer diameter (diameter) D ₄ of the cylindrical small diameter portion 142 is substantially equal to the inner diameter d ₁ of the communication hole 114 formed in the connecting portion 113 of the lid portion 112 of the valve body 110 (D ₄ ≈d ₁ ).

A disc-shaped flange portion 143 is formed at the lower end of the cylindrical small diameter portion 142 of the second plunger 140. Outer diameter (diameter) _{D 5} of the flange portion 143 has an outer diameter (diameter) larger than _{D 4} of the cylindrical small-diameter portion 142 has substantially the same size as the inner diameter _{d 2} of the valve chamber 115 _{(D 5} ≒ _{d 2>} D _4).

As described above, the cylindrical small-diameter portion 142 is disposed in the communication hole 114 formed in the connection portion 113 of the lid portion 112 of the valve body 110, and moves in the vertical direction along the axis OO ′. Moreover, the flange part 143 is arrange | positioned in the valve chamber 115 of the valve main body 110, and moves to an up-down direction along axis OO '. Incidentally, the outer diameter _{D 3} of the cylindrical body 141 is larger than the outer diameter _{D 4} of the cylindrical small-diameter portion 142 on the lower surface of the cylindrical body 141, the stepped portion 141a is formed faces downward. As shown in FIG. 1, the formed stepped portion 141 a comes into contact with the upper surface of the connecting portion 113 of the lid portion 112 of the valve body 110. Thereby, the downward movement of the second plunger 140 is prevented (see FIGS. 1 and 3).

Further, the outer diameter D ₅ of the flange portion 143 is larger than the inner diameter d ₁ of the communication hole 114 equal to the outer diameter D ₄ of the cylindrical small diameter portion 142, so that it is between the cylindrical small diameter portion 142 and the flange portion 143. On the upper surface of the flange portion 143, a step portion 143a is formed facing upward. Therefore, when the stepped portion 143a of the flange portion 143 of the second plunger 140 abuts on the stepped portion 112a formed on the lid portion 112 of the valve body 110, the second plunger 140 is prevented from further rising ( (See FIG. 2).

When the solenoid valve 100 is in the first position shown in FIG. 1, the first and second coils 121 and 126 are in the off state. Accordingly, the first plunger 130, the first coil spring 139, is urged downwardly so as to form a first gap L ₁ between the attractor 150. Similarly, the second plunger 140 is urged downward by the second coil spring 149. At this time, a second gap L ₂ is formed between the lower surface of the spring receiving portion 132 of the first plunger 130 and the upper surface of the cylindrical main body 141 of the second plunger 140. Further, the stepped portion 141 a of the cylindrical main body 141 of the second plunger 140 is in contact with the upper surface of the connecting portion 113 formed on the lid portion 112 of the valve main body 110. Further, the stepped portion 143a of the flange portion 143 and the stepped portion 112a of the lid portion 112 of the valve main body 110 are separated so as to have a _third gap L3. Therefore, in the present embodiment, the vertical length of the cylindrical small diameter portion 142 of the second plunger 140 is the vertical length of the communication hole 114 formed in the connecting portion 113 of the lid portion 112 of the valve body 110. It is designed to be a length obtained by adding a third gap L ₃ in.

The relationship between the first gap L ₁ , the second gap L _2, and the third gap L ₃ is L ₁ > L ₃ > L ₂ .

  Around the plunger tube 120, there are provided first and second coils 121 and 126 for moving the first and second plungers 130 and 140 vertically in the plunger tube 120.

  The first coil 121 that excites the first plunger 130 is wound around a coil bobbin 122 that is concentrically attached to the plunger tube 120, and is surrounded by a yoke 123 made of a magnetic material as a magnetic flux path. Reference numeral 129 denotes a lid made of a magnetic material, which is fixed to the attractor 150 by a screw 128 and also functions as a magnetic flux path.

  The second coil 126 that excites the second plunger 140 is wound around a coil bobbin 125 that is concentrically attached to the plunger tube 120, and is surrounded by a yoke 127 made of a magnetic material as a magnetic flux path. Yes.

  A spacer 124 made of a non-magnetic material such as a synthetic resin is preferably provided between the first coil 121 and the second coil 126 as shown in this embodiment.

  From the configuration of the electromagnetic valve 100 described above, the first and second plungers 130 and 140 can move independently in the vertical direction, so that the fluid can be moved as described below. The flow can be controlled.

  As shown in FIG. 1, the electromagnetic valve 100 is in a first position as a fully closed position where the valve body 135 is seated on the valve seat 105 a and blocks the flow of fluid.

Next, as shown in FIG. 2, when a current is passed through the second coil 126, that is, when the second coil 126 is turned on, a magnetic field is formed by the second coil 126, and the second plunger 140 is excited. Thereby, the second plunger 140 is attracted to the suction element 150, to raise the second plunger 140 just third gap _{L 3} minutes. Second gap _{L 2} is a third gap _{L 3} is smaller than between the spring bearing 132 of the cylindrical body 141 and the first plunger 130 of the second plunger 140. Therefore, the second plunger 140 abuts on the first plunger 130 and raises the first plunger 130 by (L ₃ −L ₂ ). When the first plunger 130 is raised, the valve element 135 is separated from the valve seat 105a, and thus the electromagnetic valve 100 is opened. At this time, the electromagnetic valve 100 is slightly opened as a position where the valve body 135 is slightly separated from the valve seat 105a, specifically, as a second position where the valve body 135 is raised about 0.2 mm from the valve seat 105a. In position.

  In this specification, the solenoid valve is in the first position when the valve body of the solenoid valve is completely seated on the valve seat, the valve seat is completely closed, and the fluid flow is completely shut off. It is said to be in the fully closed position. In addition, the state in which the valve body is not completely seated on the valve seat and the flow of fluid is hardly generated is said that the solenoid valve is in the slightly open position as the second position. The state in which the solenoid valve is in the fully open position as the third position is the state where the seat is maximally separated (raised) and the fluid flow is maximum.

  Subsequently, as shown in FIG. 3, when a current is passed through the first coil 121, that is, when the first coil 121 is turned on, a magnetic field is formed by the first coil 121, and the first plunger 130 is excited. Thereby, the first plunger 130 is sucked by the suction element 150, and the first plunger 130 is raised by {L1- (L3-L2)} until the first plunger 130 contacts the suction element 150. . At this time, the solenoid valve 100 is in the fully open position as the third position.

  Next, the solenoid valve 100 lowers the first plunger 130 until it abuts against the second plunger 140 by completely turning off the first coil 121. Thereby, the solenoid valve 100 returns to the slightly open position as the second position as shown in FIG.

  As described above, in the present embodiment, the solenoid valve 100 controls the flow of fluid between the finely open position as the second position and the fully open position as the third position. . That is, during normal use, the solenoid valve 100 moves up or down between the slightly open position as the second position and the fully open position as the third position, and only when the operation of the system is completely completed. The fully closed position is configured as the first position where the flow of fluid is blocked. By configuring the electromagnetic valve in this way, the frequency with which the valve abuts on the valve seat is reduced, wear of the valve and the valve seat is reduced, and generation of noise due to the contact between the valve and the valve seat is suppressed. Furthermore, it is possible to suppress the water hammer phenomenon caused by the complete closing of the valve. As a result, the durability of the solenoid valve can be improved.

  Next, a solenoid valve according to a second embodiment of the present invention will be described with reference to FIGS. The solenoid valve 200 according to the second embodiment is different in the configuration of the first plunger 230 and the second plunger 240. Thereby, the solenoid valve 200 of the present embodiment is not different from the first embodiment in that the solenoid valve takes the first, second and third positions, but the opening / closing operation thereof is slightly different. is there.

  As shown in FIG. 4, the electromagnetic valve 200 according to the present embodiment is roughly composed of a valve body 210, a plunger tube 220, first and second plungers 230 and 240, first and second coils 221 and 226, A suction element 250 and first and second coil springs 239 and 249 are provided. Also in this embodiment, these components constituting the electromagnetic valve 200 are assembled concentrically so that the axis O-O ′ is a common center line, as shown in FIGS.

The valve main body 210 in the present embodiment is different from the first embodiment in that the lid portion 112 has a configuration in which the lid portion 112 is formed integrally with the housing portion 111, and the other configurations are the same. . Specifically, in the present embodiment, a cylindrical connecting portion 212 to which the plunger tube 220 is connected is formed on the upper portion of the housing portion 211. A communication hole 213 that opens the valve chamber 215 upward is formed in the connection portion 212. In the communication hole 213 and the valve chamber 215, the first and second plungers 230 and 240 are concentrically attached along the axis OO ′ so as to be movable in the vertical direction, as in the first embodiment. The same. Further, the inner diameter of the communication hole 213 and _{d 5,} when the inner diameter of the valve chamber 215 and _{d 6,} it is also the same as in the first embodiment is _{d 5 <d 6.} Furthermore, when the valve body 236 is seated on the valve seat 205a and the flow of fluid is blocked, the electromagnetic valve 200 is in the fully closed position, which is the first position, as in the first embodiment. Since the other structure of the valve body 210 is the same as that of the first embodiment as described above, the description of the other structure of the valve body 210 is omitted. In addition, the other structure of the valve main body 210 can be understood by replacing the 100th series with the 200th series in the first embodiment (hereinafter, the same applies to the components whose explanation is omitted). .

The plunger tube 220 in the present embodiment is cylindrical, and has an upper end closed by a suction element 250 and a lower end closed by a valve body 210, and has the same configuration as that of the first embodiment. Therefore, the inner diameter d ₇ of the plunger tube 220 is the same as the outer diameter of the connecting portion 212 of the valve body 210.

  Also in this embodiment, the electromagnetic valve 200 includes the first and second plungers 230 and 240 as two movable iron cores, and the first coil 221 and the second coils as two solenoid coils that drive the two movable iron cores. Two coils 226 are provided.

  In the plunger tube 220, first and second plungers 230 and 240 as two movable iron cores are accommodated so as to be movable in the vertical direction along the axis O-O '. The first and second plungers 230 and 240 can move in the vertical direction as in the first embodiment when the first coil 221 and the second coil 226 are turned on and off.

The first plunger 230 is a valve attached to a cylindrical main body 231, a spring receiving portion 232, a cylindrical small diameter portion 233, a cylindrical flange portion 234, and a recess 235 formed at the lower end of the cylindrical flange portion 234. A body 236 and a first coil spring 239 are provided. This embodiment differs from the first embodiment in that a cylindrical flange portion 234 is formed at the lower end of the first plunger 230. The outer diameter D ₆ of the cylindrical main body 231 is substantially equal to the inner diameter d ₇ of the plunger tube 220. As shown in FIG. 1, the columnar body 231 is formed to be movable in the vertical direction along the axis OO ′ within the cylindrical plunger tube 220. The cylindrical body 231 of the first plunger 230 is formed to be movable in the vertical direction in the plunger tube 220, so that the valve body 236 attached to the lower end of the first plunger 230 opens and closes the valve seat 205a. To do.

Cylindrical small diameter portion 233 of the first plunger 230 has a diameter substantially equal _{D 7} to the inner diameter _{d 8} of the second central through-hole 245 of the plunger 240 smaller than the outer diameter _{D 6,} and will be described later, of the cylindrical body 231 _{(D 6> D 7 ≒ d} 8). With this configuration, the cylindrical small diameter portion 233 of the first plunger 230 passes through the center through hole 245 of the second plunger 240 and the inside of the center through hole 245 has an axis OO ′. It can move independently in the vertical direction along. Accordingly, the first plunger 230 and the second plunger 240 are independently movable in the vertical direction along the axis OO ′ with respect to each other. In the present embodiment, the columnar small diameter portion 233 is integrally connected to the columnar main body 231 by, for example, welding, brazing, screw connection, or the like.

In the present embodiment, as described above, the columnar flange portion 234 is formed at the lower end portion of the first plunger 230, that is, below the columnar small diameter portion 233 of the first plunger 230. The outer diameter D ₈ of the columnar flange portion 234 is set larger than the outer diameter D ₇ of the columnar small diameter portion 233 (D ₇ <D ₈ ), and therefore, between the columnar flange portion 234 and the columnar small diameter portion 233. The stepped portion 234a is formed on the upper surface of the cylindrical flange portion 234 so as to face upward. Outer diameter D ₈ of the cylindrical flange portion 234 is also preferably designed to have a magnitude equal to the outer diameter (diameter) D ₁₀ of the cylindrical small-diameter portion 242 of the second plunger 240 to be described later (D ₈ = _D 10). With this configuration, the stepped portion 234a of the cylindrical flange portion 234 of the first plunger 230 abuts the lower surface of the buffer portion 244 formed at the lower end of the cylindrical small diameter portion 242 of the second plunger 240 described later. Touch. Thereby, the 1st plunger 230 is prevented from raising further (refer FIG. 5).

A first coil spring 239 is provided between the cylindrical main body 231 of the first plunger 230 and the suction element 250 provided at the upper end of the plunger tube 220, and the first plunger 230 is attached downward. It is fast. As a result, the valve body 236 attached to the lower end of the first plunger 230 is seated on the valve seat 205a as shown in FIG. 4 and blocks the flow of fluid. Thus, when the solenoid valve 200 is in the first position, which is the fully closed position, the first gap L is formed between the lower surface of the attractor 250 and the upper surface of the columnar body 231 of the first plunger 230. An interval is formed to have _four . One end of the first coil spring 239 is supported by the suction element 250 and the other end is held in a recess 237 provided in the columnar body 231.

At the lower end of the plunger main body 231, a spring receiving portion 232 that supports the other end of the second coil spring 249 interposed between the first plunger 230 and the second plunger 240 is the same as in the first embodiment. Can be formed. As shown in FIG. 4, when the electromagnetic valve 200 is in the first position of the fully closed position, the second plunger 240 is urged downward by the second coil spring 249. At this time, the interval having a second gap L ₅ between the upper end of the cylindrical body 241 of the lower end and the second plunger 240 of the spring receiving portion 232 of the first plunger 230 is formed. In the case of this embodiment, the second clearance and L ₅ may be zero.

In the present embodiment, the second plunger 240 generally includes a cylindrical main body 241, a cylindrical small diameter portion 242, a buffer portion 244 provided at the lower end of the cylindrical small diameter portion 242, and a second coil spring 249. The second plunger 240 is formed with a central through hole 245 that passes from the upper cylindrical body 241 to the lower buffer portion 244. In FIG. 4, the cylindrical main body 241 is formed to be movable in the vertical direction along the axis OO ′ in the plunger tube 220. Therefore, the outer diameter D ₉ of the cylindrical body 241 is substantially equal to the inner diameter d ₇ of the plunger tube 220 (D ₆ ≈D ₉ ≈d ₇ ). Further, since the outer diameter D ₁₀ of the cylindrical small diameter portion 242 is smaller than the outer diameter D _{9 of} the cylindrical main body 241, it is between the cylindrical main body 241 and the cylindrical small diameter portion 242 and the lower surface of the cylindrical main body 241. The step portion 241a is formed facing downward. The outer diameter _{D 10} of the cylindrical small-diameter portion 242 is substantially equal to the inside diameter _{d 5} of the communication hole 213 formed in the connecting portion 212 of the valve body _{110 (D 10 ≒ d 5)} .

In the present embodiment, a cylindrical buffer portion 244 is formed integrally with the cylindrical small diameter portion 242 at the lower end of the cylindrical small diameter portion 242 of the second plunger 240. When the lower surface of the buffer portion 244 comes into contact with the stepped portion 234a formed on the cylindrical flange portion 234 of the first plunger 230, the buffer portion 244 is made of, for example, PTFE (polytetrafluoroethylene) so as to reduce the impact. It is preferable to form it from a buffer member. The outer diameter of the buffer section 244 preferably has the same size as the outer diameter D ₁₀ of the cylindrical small-diameter portion 242.

  As described above, the cylindrical small-diameter portion 242 is disposed in the communication hole 213 formed in the connecting portion 212 of the valve body 210, and moves in the vertical direction along the axis O-O ′. When the second plunger 240 is lowered, the stepped portion 241 a formed downward on the lower surface of the cylindrical main body 241 contacts the upper surface of the connecting portion 212 of the valve main body 210. Thereby, the downward movement of the second plunger 240 is prevented (see FIGS. 4 and 5).

When the solenoid valve 200 is in the first position of the fully closed position shown in FIG. 4, the first and second coils 221 and 226 are in the off state. Accordingly, the first plunger 230 is urged downward by the first coil spring 239 so as to form the first gap L ₄ between the first plunger 230 and the suction element 250. Similarly, the second plunger 240 is urged downward by the second coil spring 249. In this case, between the upper surface of the cylindrical body 241 lower surface of the second plunger 240 of the spring receiving portion 232 of the first plunger 230, the interval having a second gap which L ₅ is formed. Further, the stepped portion 241 a of the cylindrical main body 241 of the second plunger 240 is in contact with the upper surface of the connecting portion 212 formed on the valve main body 2. Further, a third gap L ₆ is formed between the lower surface of the buffer portion 244 of the second plunger 240 and the step portion 234 a of the cylindrical flange portion 234 of the first plunger 230. In the present embodiment, the relationship between the first gap L ₄ , the second gap L _5, and the third gap L ₆ is L ₄ > L ₆ > L ₅ .

  Also in the present embodiment, the first and second coils 221 and 226 for moving the first and second plungers 230 and 240 in the plunger tube 220 in the vertical direction are provided around the plunger tube 220. Since the structures of the first and second coils 221 and 226 are substantially the same as those of the first embodiment, description thereof is omitted.

  From the configuration of the electromagnetic valve 200 described above, the first and second plungers 230 and 240 can move independently in the vertical direction, so that the flow of fluid can be described as described below. Can be controlled.

  As shown in FIG. 4, the electromagnetic valve 200 is in a first position as a fully closed position where the valve body 236 is seated on the valve seat 205 a and blocks the flow of fluid.

Next, as shown in FIG. 5, in the present embodiment, first, a current is passed through the first coil 221 to turn on the first coil 221. When a current flows through the first coil 221, a magnetic field is formed, and the first plunger 230 is excited. Thereby, the first plunger 230 is sucked by the suction element 250 and moves upward. At this time, since the second coil 226 is not excited in the second plunger 240, the step portion 241 a formed on the lower surface of the cylindrical main body 241 is formed by the second coil spring 249 on the connecting portion 212 of the valve main body 210. The position in contact with the upper surface is held. The third gap _{L 6,} which are set smaller than the first gap _{L 4} formed between the first plunger 230 and the suction element 250, a first plunger 230, a valve seat 205a To the third gap L ₆ minutes.

As the first plunger 230 moves up, the electromagnetic valve 200 is opened. At this time, as shown in FIG. 5, the electromagnetic valve 200 is in the slightly open position as the second position, which is elevated about 0.2 mm from the valve seat 205a, as in the first embodiment. Further, the distance between the suction element 250 and the first plunger 230 is (L ₄ −L ₆ ). Furthermore, the distance between the lower surface of the spring receiving portion 232 of the first plunger 230 and the upper surface of the cylindrical main body 241 of the second plunger 240 is (L ₅ + L ₆ ).

Subsequently, as shown in FIG. 6, when a current is passed through the second coil 226 and the second coil 226 is turned on, a magnetic field is formed by the second coil 226 and the second plunger 240 is excited. Is done. Accordingly, the second plunger 240 is also sucked by the suction element 250, and the first plunger 230 and the second plunger 240 are brought together (L ₄ -L) until the first plunger 230 abuts on the suction element 250. ₆ ) Raise by the minute. As a result, the first plunger 230 will be raised by the first gap L ₄ minutes. Further, a gap having a gap (L ₄ -L ₆ ) is formed between the stepped portion 241 a of the cylindrical main body 241 of the second plunger 240 and the upper surface of the connecting portion 212 of the valve main body 210. At this time, the solenoid valve 200 is in the fully open position as the third position. Further, while the first and second plungers 230 and 240 are raised together, the distance (L ₅ + L ₆ ) formed between the first plunger 230 and the second plunger 240 is maintained. Is done.

  Next, the solenoid valve 200 turns off the second coil 226 completely. Accordingly, the first and second plungers 230 and 240 are joined together until the stepped portion 241a formed on the lower surface of the cylindrical main body 241 of the second plunger 240 abuts on the upper end of the connecting portion 212 of the valve main body 210. Descend. As a result, the electromagnetic valve 200 returns to the slightly open position as the second position as shown in FIG.

  As described above, also in the present embodiment, the electromagnetic valve 200 controls the flow of fluid between the finely open position as the second position and the fully open position as the third position. And the solenoid valve 200 in this embodiment is also comprised so that it may not take the fully closed position as a 1st position where the flow of the fluid is interrupted | blocked completely at the time of normal use. Therefore, the electromagnetic valve in the present embodiment can also exhibit the same operational effects as the electromagnetic valve 100 in the first embodiment.

100, 200 Solenoid valve 105, 205 Seat member 105a, 205a Valve seat 110, 210 Valve body 113, 212 Connecting portion 114, 213 Communication hole 115, 215 Valve chamber 120, 220 Plunger tube 121, 221 First coil 126, 226 Second coil 130, 230 First plunger
131, 231 Columnar body 133, 233 Columnar small diameter portion 135, 236 Valve body 140, 240 Second plunger 141, 241 Cylindrical body 142, 242 Cylindrical small diameter portion 143 Flange portion 145, 245 Center through hole 150, 250 Suction element 234 Flange

Claims (8)

A valve body, a plunger tube, first and second plungers movable in the plunger tube, first and second coils for independently exciting the first and second plungers, and the excited first In an electromagnetic valve including at least an attractor capable of attracting the first and second plungers,
The valve body is connected to the plunger tube, the connecting portion through which the first and second plungers penetrate, the valve chamber communicating with the inlet side fluid passage and the outlet side fluid passage, and the inlet side fluid passage and the outlet side fluid. A seat member having a valve seat provided between the passage and the valve chamber;
The plunger tube is provided with the first and second plungers that are independently movable in the vertical direction,
Around the plunger tube, the first and second coils are provided corresponding to the first and second plungers, respectively.
The first plunger is further provided so as to be vertically movable through a central through hole formed in the second plunger, and a lower end portion of the first plunger is seated on or separated from the valve seat, A valve body that can open and close the valve seat is provided,
The second plunger is further provided so as to be movable in the vertical direction through a communication hole formed in the connecting portion of the valve body.
The valve body provided on the first plunger moves to the first position, which is a position where the electromagnetic valve is completely closed by being seated on the valve seat, and is moved upward by being separated from the valve seat. The electromagnetic valve can be moved to a second position, which is a slightly opened position, and a third position, which is a position where the electromagnetic valve is fully opened by moving further sufficiently upward from the valve seat. And solenoid valve.   2. The solenoid valve according to claim 1, wherein the plunger tube, the first and second plungers, the valve chamber of the valve body, and the seat member are arranged concentrically. The first plunger has a cylindrical main body that is movable in the vertical direction in the plunger tube, an outer diameter smaller than the outer diameter of the cylindrical main body, and the same outer diameter as the inner diameter of the central through hole of the second plunger. A cylindrical small-diameter portion, comprising the spherical valve body fixed in a recess formed in the lower end portion of the cylindrical small-diameter portion,
The second plunger includes a cylindrical main body that is movable in the vertical direction in the plunger tube, an outer diameter of the cylindrical main body, and an inner diameter of a communication hole formed in the connecting portion of the valve main body. A cylindrical small-diameter portion having the same outer diameter, a flange portion formed at the lower end of the cylindrical small-diameter portion, having an outer diameter larger than the outer diameter of the cylindrical small-diameter portion, and movable in the valve chamber in the vertical direction The electromagnetic valve according to claim 2, comprising: The first plunger includes a first coil spring, and the first coil spring forms a _first gap (L ₁ ) between the suction element and the first plunger, and the valve body is Urging the first plunger downward to close the valve seat;
The second plunger includes a second coil spring, and the second coil spring forms a _second gap (L ₂ ) between the first plunger and the second plunger, and the second coil spring The lower surface of the cylindrical main body of the plunger is in contact with the upper surface of the connecting portion of the valve main body, and between the upper surface of the flange portion of the second plunger and the upper surface of the valve chamber of the valve main body. Urging the second plunger downward to form a _third gap (L ₃ );
4. The solenoid valve according to claim 3, wherein the sizes of the first, second, and third gaps have a relationship of L ₁ > L ₃ > L ₂ . The solenoid valve is in the first position when no current is passed through the first and second coils;
When a current is passed through the second coil, the second plunger is excited, whereby the second plunger is attracted by the attractor, and the upper surface of the flange portion of the second plunger is the valve. The second plunger rises against the urging force of the second coil spring until it comes into contact with the upper surface of the valve chamber of the main body, and the first plunger is also moved to the third position by the rise of the second plunger. Is increased by the difference between the gap and the second gap, whereby the valve body is separated from the valve seat, so that the electromagnetic valve is in the second position,
Further, when a current is passed through the first coil, the first plunger is excited, and is thereby attracted to the attractor, and the first coil spring until the first plunger comes into contact with the attractor. The solenoid valve according to claim 4, wherein the solenoid valve is in the third position by being raised against the urging force. The first plunger has a cylindrical main body that is movable in the vertical direction in the plunger tube, an outer diameter smaller than the outer diameter of the cylindrical main body, and the same outer diameter as the inner diameter of the central through hole of the second plunger. A cylindrical small-diameter portion, formed at the lower end of the cylindrical small-diameter portion, fixed in a flange portion having an outer diameter larger than the outer diameter of the cylindrical small-diameter portion, and a recess formed on the lower surface side of the flange portion. Comprising a spherical valve body,
The second plunger includes a cylindrical main body that is movable in the vertical direction in the plunger tube, an outer diameter of the cylindrical main body, and an inner diameter of a communication hole formed in the connecting portion of the valve main body. The solenoid valve according to claim 2, further comprising a cylindrical small-diameter portion having the same outer diameter. The first plunger includes a first coil spring, and the first coil spring forms a first gap (L ₄ ) between the suction element and the first plunger, and the valve body is Urging the first plunger downward to close the valve seat;
The second plunger includes a second coil spring, and the second coil spring forms a second gap (L ₅ ) between the first plunger and the second plunger. The lower surface of the cylindrical main body of the plunger is in contact with the upper surface of the connecting portion of the valve main body, and between the upper surface of the flange portion of the second plunger and the upper surface of the valve chamber of the valve main body. Urging the second plunger downward to form a third gap (L ₆ );
The solenoid valve according to claim 6, wherein the first, second, and third gaps have a relationship of L ₄ > L ₆ > L ₅ . The solenoid valve is in the first position when no current is passed through the first and second coils;
When a current is passed through the first coil, the first plunger is excited and is thereby attracted by the attractor, and the upper surface of the flange portion of the first plunger is the surface of the second plunger. Until the first lower end of the cylindrical small-diameter portion abuts against the urging force of the first coil spring, the first plunger moves up against the urging force of the first coil spring so that the valve body is separated from the valve seat. In the second position,
Further, when a current is passed through the second coil, the second plunger is further excited, whereby the second plunger is also attracted by the attractor, and the first plunger is moved together with the second plunger. The electromagnetic valve according to claim 7, wherein the electromagnetic valve is in the third position by moving up against the urging force of the first and second coil springs until contacting the attractor. .

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