JP2023131585A - electromagnetic actuator - Google Patents

Abstract

To improve magnetic suction efficiency of a plunger, and to further increase a stroke of the plunger.SOLUTION: A stepped portion is formed at a position separated in a second direction by a predetermined distance from a magnetic throttling portion in an inner peripheral portion of a stator core, and a stator tapered portion gradually decreasing a diameter from the stepped portion toward the second direction is formed. A shoulder portion opposing to the stepped portion is formed on an outer peripheral portion of a plunger. A plunger tapered portion gradually decreasing a diameter with generally a same inclined angle as the stator tapered portion, is formed. A ring-shaped magnetic concentration portion is formed at a tip end, and a recessed portion is formed therein. A magnetic flux is concentrated on the ring-shaped magnetic concentration portion, suction force is raised, and thus a stroke of the plunger is increased.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to an electromagnetic actuator, and is suitable for use in, for example, an electromagnetic valve that opens and closes a flow path of a working fluid.

Patent Document 1 discloses an electromagnetic actuator used in an electromagnetic valve that switches the flow path of washer fluid. In Patent Document 1, the suction surface of the electromagnetic actuator is formed into a stepped portion consisting of a tapered surface and a flat surface, thereby achieving miniaturization of the electromagnetic valve while maintaining suction force.

On the other hand, in recent years, there has been a demand for increasing the stroke of the valve body in order to reduce pressure loss when fluid passes through the electromagnetic valve. Electromagnetic actuators are required to have a larger plunger stroke. Therefore, in order to increase the stroke of the plunger while maintaining the physique of the electromagnetic actuator, it is necessary to further improve the suction efficiency.

Japanese Patent Application Publication No. 2021-143747

In view of the above points, an object of the present disclosure is to provide an electromagnetic actuator that can further increase the magnetic attraction efficiency of the plunger and increase the stroke of the plunger.

A first aspect of the present disclosure provides a coil that is excited when energized, a stator core made of a magnetic material that is disposed in a magnetic circuit when the coil is energized, and has a magnetic constriction part, and a stator core that is made of a magnetic material and is arranged in a magnetic circuit when the coil is energized. The electromagnetic actuator includes a plunger made of a magnetic material that is arranged to face the stator core through a magnetic gap, and a plunger spring that biases the plunger in a first direction away from the stator core.

The first stator core of the present disclosure has a cylindrical shape, and has a step bent radially inward at a position a predetermined distance away from the magnetic constriction portion in a second direction opposite to the first direction. In addition, the inner peripheral portion forms a stator taper portion whose diameter gradually decreases in the second direction from the stepped portion.

The first plunger of the present disclosure has a cylindrical shape, and has a shoulder portion facing the stepped portion formed on its outer periphery, and a stator tapered portion in which the diameter of the outer periphery extends from the molded portion toward the second direction. A plunger taper portion is formed that gradually decreases at approximately the same inclination angle, and a ring-shaped magnetic concentration portion is formed at the tip of the plunger taper portion in the second direction, and the radially inner side of the ring-shaped magnetic concentration portion is formed in the first direction. A concave portion is formed.

In the first aspect of the present disclosure, a ring-shaped magnetic concentration part is formed at the tip in the second direction of the plunger taper part, and the radially inner side of the ring-shaped magnetic concentration part is a recessed part depressed in the first direction. The magnetic flux directed in the second direction can be concentrated in the ring-shaped magnetic concentration portion. As a result, the suction force can be increased when the suction gap is large, leading to an increase in the stroke of the plunger.

In the second disclosure, the magnetic constriction portion is formed as a thin wall portion of the stator core. By forming the magnetic constriction directly on the stator core, it can be made into one piece, the plunger volume can be increased, and the amount of magnetic flux passing through can be increased. This also makes it possible to increase the overall suction power.

In the third disclosure, a washer made of a non-magnetic material is disposed on either the stepped portion or the plunger shoulder. This prevents the plunger from being attracted to the stator core due to residual magnetism, and when the coil is not energized, the plunger is pulled away from the stator core in the first direction by the plunger spring.

Fourthly, in the present disclosure, a second stepped portion facing the ring-shaped magnetic concentration portion of the plunger is formed on the second direction side of the stator taper portion of the stator core. By arranging the second stepped portion to face the ring-shaped magnetic concentration portion of the plunger, the magnetic attraction force in the second direction can be further increased.

A fifth aspect of the present disclosure provides a valve body having an inflow passage for a working fluid, an outflow passage for the working fluid, a valve seat formed between the inflow passage and the outflow passage and against which a valve body abuts, and a valve body that includes a valve body. It further includes a valve spring biasing in two directions. When the plunger moves in the second direction when the coil is energized, the valve body moves in the second direction under the urging force of the valve spring. In the fifth aspect of the present disclosure, the electromagnetic actuator can be used as a solenoid valve.

FIG. 2 is a diagram illustrating a piping configuration of an electromagnetic actuator. FIG. 3 is a cross-sectional view of an electromagnetic actuator. FIG. 3 is an enlarged cross-sectional view of the stator core and plunger of FIG. 2; FIG. 3 is a cross-sectional view showing magnetic flux in a comparative example. FIG. 3 is a sectional view showing the magnetic flux of the electromagnetic actuator shown in FIG. 2; It is a sectional view showing other examples of a valve housing. It is a figure explaining other examples of piping composition of an electromagnetic actuator.

An example in which the electromagnetic actuator 100 of the present disclosure is used as the electromagnetic valve 200 will be described. This is a solenoid valve 200 disposed in the piping 10 as shown in FIG. 1, and an on-off valve that switches on and off a flow path is used as the solenoid valve 200. A nozzle 11 disposed at the tip of the pipe 10 faces the rear window glass 13 and jets washer fluid onto the rear window glass 13. The camera nozzle 14 of the camera pipe 12 spouts washer fluid to the camera 15.

Note that the washer fluid is stored in the tank 16 and is injected by the discharge force of the pump 17. Further, a stop valve 18 is arranged between the solenoid valve 200 and the nozzle 11 and between the solenoid valve 200 and the camera nozzle 14. The stop valve 18 is used to improve the draining of the washer fluid at the end of injection.

As shown in FIG. 2, the electromagnetic actuator 100 includes a coil bobbin 101 made of resin and a coil 102 made of an enamelled copper wire wound around the coil bobbin 101 many times. The coil bobbin 101 is made of polyphenylene sulfide (PPS), for example, and the stator core 110 is disposed on the inner periphery thereof. The stator core 110 is made of a magnetic material, such as SUS430.

Further, the outer periphery of the coil bobbin 101 is covered with an outer shell 120 made of resin. The outer shell 120 is also made of polyphenylene sulfide (PPS), for example, and is formed integrally with the connector 121. A pair of terminals 122 are embedded in the connector 121, and the pair of terminals 122 are connected to the plus side and the minus side of the coil 102, respectively.

As shown in FIG. 3, the stator core 110 has a cylindrical shape with a closed end 111. A magnetic constriction portion 112 is formed in the middle portion of the stator core 110 . The magnetic constriction portion 112 is formed by forming a thin portion of the stator core 110 with a wall thickness of about 1 mm or less.

A plunger 130 is arranged on the inner periphery of this stator core 110. The plunger 130 has a cylindrical shape and is made of a magnetic material such as SUS430. A plunger spring 140 is arranged between the plunger 130 and the end 111 of the stator core 110 to bias the plunger 130 in a direction to separate it from the stator core 110. In the following description, the direction in which plunger 130 is pulled away from stator core 110 will be referred to as the first direction. The first direction corresponds to the downward direction of FIGS. 2 and 3. A direction opposite to the first direction is defined as a second direction. The second direction corresponds to the upper side of FIGS. 2 and 3.

FIG. 3 shows an enlarged view of the electromagnetic actuator 100 portion in FIG. A stepped portion 113 bent inward in the radial direction is formed at a position a predetermined distance (approximately 1 millimeter) away from the magnetic constriction portion 112 of the stator core 110 in the second direction. In this example, the width of the stepped surface of the stepped portion 113 is approximately 1 mm or less. A stator tapered portion 114 whose diameter gradually decreases in the second direction from the stepped portion 113 is formed in the inner peripheral portion of the stator core 110. The angle of inclination of this stator tapered portion 114 is about 5 to 25 degrees on both sides. Further, the length of the stator tapered portion 114 in the second direction is approximately several millimeters. A second stepped portion 115 is also formed at the end of the stator tapered portion 114 in the second direction. The width of the stepped surface of the second stepped portion is also approximately 1 mm or less.

The above-mentioned plunger spring 140 is arranged in the second cylindrical part 118 of the stator core 110 on the second direction side with respect to the magnetic constriction part 112. The stator core 110 also has a cylindrical shape on the first direction side from the magnetic constriction part 112, forming a first cylindrical part 117. The open end of the first cylindrical portion 117 extends outward in the radial direction in the shape of a disk to form the flange portion 116 .

A plunger shoulder 131 facing the stepped portion 113 of the stator core 110 is formed at the end of the plunger 130 in the second direction. Further, a plunger taper portion 132 whose diameter gradually decreases in the second direction from the plunger shoulder portion 131 is formed on the outer peripheral portion of the end portion in the second direction of the plunger 130 . The angle of inclination of the plunger taper portion 132 gradually decreases at approximately the same angle as the angle of inclination of the stator taper portion 114.

The plunger 130 has a ring-shaped magnetic concentration part 133 formed continuously at the tip of the plunger taper part 132 in the second direction. This ring-shaped magnetic concentration portion 133 faces the second stepped portion 115 of the stator core 110 described above. A concave portion 134 recessed in the first direction is formed on the radially inner side of the ring-shaped magnetic concentration portion 133 of the plunger 130 . Thereby, the ring-shaped magnetic concentration part 133 is located at the tip of the plunger 130 in the second direction.

The first direction end portion of the plunger spring 140 described above is supported by this recess 134. Further, the end portion of the plunger spring 140 in the second direction is supported by the end portion 111 of the stator core 110.

A washer 135 is engaged with a plunger shoulder 131 of the plunger 130 . The washer 135 is made of a non-magnetic material such as SUS304, and prevents the magnetic stator core 110 and the plunger 130 from remaining attracted to each other due to residual magnetic force after the energization ends. Note that the plunger 130 is guided by the first cylindrical portion 117 of the stator core 110 and moves in the first direction and the second direction in FIGS. 2 and 3. The movement of the plunger 130 in the second direction is regulated by the washer 135 coming into contact with the stepped portion 113. In other words, while the washer 135 is in contact with the stepped portion 113, the stator taper portion 114 and the plunger taper portion 132 are not in contact with each other. Similarly, the ring-shaped magnetic concentration part 133 also does not come into contact with the second stepped part 115.

A yoke 150 is arranged further on the outer periphery of the outer shell 120 of the coil bobbin 101. The yoke 150 is made of magnetic steel, such as cold rolled steel plate (SPCE). When the coil 102 is energized, a magnetic circuit is formed by the yoke 150, the stator core 110, and the plunger 130.

The electromagnetic actuator 100 having this structure is assembled in the following steps. First, the coil 102 is wound many times around the outer periphery of the coil bobbin 101, and the pair of terminals 122 and both ends of the winding of the coil 102 are connected. In this state, the outer shell 120 and the connector 121 are molded with resin.

Next, the stator core 110 is arranged around the inner periphery of the coil bobbin 101. After that, the yoke 150 is arranged around the outer circumference of the outer shell 120. Plunger spring 140 and plunger 130 are arranged within second cylindrical section 118 and first cylindrical section 117 of stator core 110 when assembled with valve section 201, which will be described later.

The electromagnetic actuator 100 is configured with the above configuration. This electromagnetic actuator 100 is coupled to a valve portion 201 via an O-ring 210. Note that the O-ring 210 is made of ethylene propylene rubber (EPDM) or the like. The electromagnetic actuator 100 and the valve section 201 are combined to form the electromagnetic valve 200.

The valve portion 201 includes a valve body 220 made of resin such as polyphenylene sulfide (PPS). The valve body 220 is formed with an inflow passage 221 through which high-pressure washer fluid from the pump 17 flows, and an outflow passage 222 connected to the piping 10 leading to the rear window glass 13 and the camera piping 12 heading to the camera 15. . Both the inlet passage 221 and the outlet passage 222 have an inner diameter of about 3 mm. The outer circumferences of the ends of the inflow passage 221 and the outflow passage 222 are tapered to facilitate connection of piping. A pipe shoulder 224 is formed at the tapered end to prevent the pipe from coming off.

A valve chamber 223 is formed in the valve body 220, and the valve chamber 223 communicates with the inflow passage 221. Valve chamber 223 also communicates with outflow passage 222 via valve seat 227 . The valve seat 227 has an arcuate or tapered cross section. The inner diameter of the valve seat 227 is a little less than 5 mm.

A valve body 230 is arranged within the valve chamber 223 so as to be able to abut against the valve seat 227 . The valve body 230 includes a main valve 231 made of resin and having a cylindrical shape, and an abutment member 232 arranged at the end of the main valve 231 in the first direction. The end portion of the main valve 231 in the second direction is formed into a disk shape, and a stopper 2310 is formed on the outer periphery of the main valve 231 to come into contact with the flange portion 116 of the stator core 110 when the valve body 230 moves in the second direction.

The contact member 232 is made of a rubber material such as ethylene propylene rubber (EPDM), and seals the valve seat 227 when seated on the valve seat 227. Therefore, the shape of the first direction end portion 2321 of the contact member 232 is an arcuate shape or a tapered shape corresponding to the cross-sectional shape of the valve seat 227. The contact member 232 is integrally molded from water-resistant rubber, and its surface is coated. This coating material is a substance such as fluorine or molybdenum that prevents the surface of the rubber from melting and improves the seating ability of the valve body and the mating valve seat.

A passage hole 2323, which serves as a passage for a pressure relief valve 240 to be described later, passes through the central shaft portion of the contact member 232. The contact member 232 is press-fitted into the main valve 231 and moves together as the valve body 230. That is, the contact member 232 and the main valve 231 move together as the valve body 230 in the first direction and the second direction.

A valve spring 233 is disposed in the valve chamber 223 around the outer periphery of the main valve 231, and the valve spring 233 biases the valve body 230 in the second direction. The valve spring 233 is provided to stabilize the position of the valve body 230 within the valve chamber 223. Therefore, the spring force of the valve spring 233 is smaller than the spring force of the plunger spring 140.

A pressure relief valve 240 is arranged inside the main valve 231 . The pressure relief valve 240 faces the second end 2322 of the abutting member 232 and is seated on the second end 2322 by a pressure relief valve spring 241 . The pressure relief valve spring 241 releases the contact member 232 in the second direction when the washer fluid pressure on the outflow passage 222 side becomes higher than the pressure on the inflow passage 221 side by a predetermined pressure set by the pressure relief valve spring 241. It separates from the end 2322. The set pressure (release pressure) of this pressure relief valve spring 241 is about 5 kilopascals, which is about half the set pressure (release pressure) of the stop valve 18.

The pressure relief valve 240 has a cylindrical shape, and three pressure relief grooves are formed on the outer periphery to allow washer fluid to flow. The pressure relief groove is semicircular with a radius of about 0.3 mm.

A connecting portion 225 for connecting to the electromagnetic actuator 100 is formed at the end of the valve body 220 in the second direction. The connecting portion 225 has a cylindrical shape, and the first direction end portion of the plunger 130 is arranged inside. Further, the upper portion of the connecting portion 225 widens to form a surface for receiving the O-ring 210 and to form a locking shoulder portion 226 that locks with the yoke 150.

Next, a method of assembling the electromagnetic valve 200 having the above structure will be explained. First, the valve body 230 and the check valve are assembled. In this assembly, first, the pressure relief valve spring 241 and the pressure relief valve 240 are inserted into the main valve 231. In this state, the abutting member 232 is fitted into the first direction open end of the main valve 231 to fix the main valve 231 and the abutting member 232 together. The valve body 230, pressure relief valve 240, and valve spring 233 assembled in this way are placed in the valve chamber 223, and the valve portion 201 is assembled.

After assembling the electromagnetic actuator 100 as described above, the O-ring 210 is placed on the connection portion 225 of the valve body 220. At this time, a plunger spring 140 is arranged inside the second cylindrical part 118 of the stator core 110, and a plunger 130 is arranged in the first cylindrical part 117. Thereafter, the end of the yoke 150 is fixed to the locking shoulder 226 of the valve body 220 by caulking. The crimping is performed all around the yoke 150 except for the portion where the connector 121 is located.

By caulking the yoke 150, the connecting portion 225 of the valve body 220 comes into contact with the flange portion 116 of the stator core 110. Then, by caulking, the O-ring 210 is compressed and deformed by the flange portion 116 of the stator core 110 and the connecting portion 225 of the valve body 220.

Next, the operation of the electromagnetic valve 200 of the present disclosure will be explained. An inflow passage 221 and an outflow passage 222 are communicated with each other when the washer liquid is ejected from the nozzle 11 toward the rear window glass 13 and when the washer liquid is ejected from the camera nozzle 14 toward the camera 15. Therefore, the coil 102 of the electromagnetic actuator 100 is energized. The behavior of the electromagnetic actuator 100 will be described later.

When the pump 17 starts operating, high-pressure washer fluid is sent to the electromagnetic valve 200 via the piping 10 and the camera piping 12. The sent washer fluid flows into the inflow passage 221 and then flows out from the outflow passage 222 via the valve chamber 223 and the valve seat 227.

The washer fluid that has passed through the electromagnetic valve 200 is injected onto the rear window glass 13 from a nozzle 11 via a pipe 10. Further, the liquid is ejected from the camera nozzle 14 to the camera 15 via the camera pipe 12. The washer fluid may be sprayed onto both the rear window glass 13 and the camera 15, or only one of them may be sprayed. In the case of only one of them, the electromagnetic actuator 100 is energized only to the electromagnetic valve 200 that requires injection.

When only one of the solenoid valves 200 is opening the valve seat 227, the high-pressure washer fluid from the pump 17 is also supplied to the other solenoid valve 200. However, when the valve body 230 is seated on the valve seat 227, the pressure of the washer fluid acts in a direction that presses the valve body 230 toward the valve seat 227. Therefore, the valve seat 227 is reliably sealed by the abutment member 232. Note that since the pressure of the washer fluid rises to about 400 kilopascals, the release pressure of the stop valve 18 (about 10 kilopascals) is hardly a problem.

When cleaning of the rear window glass 13 and camera 15 is completed, the pump 17 is stopped. When the pump 17 is stopped, the pressure inside the piping 10 and the camera piping 12 becomes atmospheric pressure, so the stop valve 18 closes them. By closing the stop valve 18, it is possible to improve liquid drainage at the end of injection. Additionally, washer fluid can be stored in the piping 10 and camera piping 12, and responsiveness during the next operation can be improved.

Next, the operation of the electromagnetic actuator 100 will be explained. In operation, coil 102 is energized. The coil 102 is excited by the energization, and a magnetic circuit is formed around the coil 102. The magnetic circuit is formed in a yoke 150 and stator core 110 that are made of magnetic material. Since a magnetic constriction section 112 is formed in the stator core 110, the magnetism bypasses this magnetic constriction section 112. Specifically, the flow flows from the first cylindrical portion 117 of the stator core 110 to the plunger taper portion 132 of the plunger 130, flows from the plunger taper portion 132 and the ring-shaped magnetic concentration portion 133 of the plunger 130 to the stator taper portion 114, and flows into the stator core 110. It flows into the second cylindrical portion 118 of. Note that the flow direction of the magnetic flux may be directed from the second cylindrical portion 118 to the first cylindrical portion 117 depending on the direction of the applied current.

Immediately after the coil 102 is energized, when the distance between the plunger taper portion 132 and the stator taper portion 114 is large, an attractive force F1 is generated between the plunger taper portion 132 and the stator taper portion 114, as shown in FIG. This suction force F1 is decomposed into F1V, which is a force acting in the axial direction (second direction) of the stator core 110 and the plunger 130, and F1R, which is a force acting in the radial direction of the stator core 110 and the plunger 130.

Among them, the force F1V acting in the second direction causes the plunger 130 to move in the second direction (upward). As the plunger 130 moves and the overlap between the plunger taper section 132 and the stator taper section 114 widens, the magnetic attraction gap becomes smaller. Therefore, as the plunger 130 moves in the second direction, the force F1R in the radial direction increases and the force F1V in the second direction decreases accordingly.

However, as the gap between the plunger 130 and the stator core 110 decreases as the plunger 130 moves in the second direction, the gap between the stepped portion 113 of the stator core 110 and the plunger shoulder 131 also decreases. Therefore, the suction force F2 in the second direction acting between the stepped portion 113 and the plunger shoulder portion 131 increases. Similarly, the distance between the second stepped portion 115 of the stator core 110 and the ring-shaped magnetic concentration portion 133 is also narrowed. Therefore, the suction force F2 in the second direction acting between the second stepped portion 115 and the plunger shoulder portion 131 also increases. As a result, the magnetic force that attracts the plunger 130 in the second direction can be maintained.

As a comparative example, the shape of the tapered portion shown in Patent Document 1 is shown in FIG. In the example of FIG. 4, the stator core 110 is divided into a first cylindrical portion 117 and a second cylindrical portion 118, which are connected by a sleeve 119 made of a non-magnetic material. Therefore, a magnetic constriction section is formed by the part divided into the first cylindrical section 117 and the second cylindrical section 118.

As described above, in the plunger 130 and the stator core 110, movement of magnetic flux occurs between the magnetic gap between the plunger taper portion 132 and the stator taper portion 114. However, there is space between the tapered surfaces and the magnetic resistance is large. Since the magnetic flux tends to flow in a place where magnetic resistance is small, in the comparative example shown in FIG. In other words, the magnetic flux does not remain in the plunger taper portion 132 but escapes to the convex portion X. Then, a magnetic flux Y is generated that moves from the convex portion X to the stator tapered portion 114. The magnetic flux Y from the convex portion X reduces the magnetic flux Z flowing through the plunger taper portion 132, which results in a reduction in magnetic attraction efficiency.

On the other hand, in the present disclosure, as shown in FIG. 5, the convex portion X is eliminated. By forming the recess 134, the tip of the plunger 130 in the second direction becomes a ring-shaped magnetic concentration part 133. As a result, the magnetic flux passing through the plunger 130 does not escape outside the plunger taper portion 132. The magnetic flux flowing in the second direction through the plunger taper portion 132 is concentrated without escaping from the ring-shaped magnetic concentration portion 133, and a highly efficient magnetic attraction force can be obtained.

Due to such magnetic attraction force, the plunger 130 moves in the second direction against the compressive force of the plunger spring 140. In particular, in the present disclosure, as described above, since the magnetic attraction efficiency of the electromagnetic actuator 100 is increased, it is possible to increase the stroke of the plunger 130.

As the plunger 130 moves, the valve body 230 is pushed up by the valve spring 233 and separated from the valve seat 227. The movement of the valve body 230 in the second direction is basically performed until the plunger shoulder 131 abuts the stepped portion 113 of the stator core 110. However, in this example, in order to stabilize the behavior of the valve body 230, the movement of the valve body 230 in the second direction ends when the stopper 2310 of the main valve 231 comes into contact with the flange 116 of the stator core 110.

Note that the above operation of the solenoid valve 200 is performed before the pump 17 starts operating. Therefore, the pressure of the high-pressure washer fluid from the pump 17 is applied in a direction that separates the valve body 230 from the valve seat 227. That is, the pressure of the washer fluid is applied in a direction that assists the operation of the electromagnetic actuator 100. At least, the movement of the valve body 230 is not hindered by the pressure of the washer fluid.

When cleaning of the rear window glass 13 and the camera 15 is completed, the operation of the pump 17 is stopped, and when the pressure in the pipe 10 and the camera pipe 12 falls below the release pressure of the stop valve 18, the stop valve 18 is also closed. At the same time, the energization of the coil 102 of the electromagnetic actuator 100 also ends. Since a washer 135 made of a non-magnetic material is interposed between the stepped portion 113 of the stator core 110 and the plunger shoulder portion 131, the plunger 130 is pushed down by the plunger spring 140 when the energization ends.

Since the biasing force of the plunger spring 140 is greater than the biasing force of the valve spring 233, the valve body 230 is pressed against the valve seat 227. Since both the valve seat 227 and the abutting member 232 of the valve body 230 have an arc shape or a tapered shape, a reliable seal can be achieved as described above.

When the ambient temperature rises after the operation of the pump 17 is finished, the washer fluid and air in the piping 10 and camera piping 12 expand. In this state, both the valve seat 227 and the stop valve 18 are closed, so the washer fluid is trapped inside the piping 10 and the camera piping 12. Therefore, the pressure inside the piping 10 and the camera piping 12 may increase due to expansion of the washer fluid and air.

If the pressure exceeds the release pressure of the stop valve 18, there is a risk that washer fluid in the piping 10 and camera piping 12 may drip from the nozzle 11 onto the rear window glass 13 or leak from the camera nozzle 14 into the camera 15. . However, in the present disclosure, since the pressure relief valve 240 opens to release pressure, leakage of washer fluid can be reliably prevented.

When the pressure inside the pipe 10 or the camera pipe 12 becomes higher than the relief pressure, the urging force of the pressure relief valve spring 241 is overcome and the pressure relief valve 240 is lifted. As a result, the second direction end 2322 of the abutment member 232 is opened, and the passage hole 2323 is opened. The outflow passage 222 communicates with the inflow passage 221 via the pressure relief groove of the pressure relief valve 240 and the valve chamber 223 .

The relief pressure of the pressure relief valve 240 is about half the release pressure of the stop valve 18. Therefore, the pressure relief valve 240 opens before the stop valve 18 opens, and it is possible to suppress the pressure increase in the pipe 10 and the camera pipe 12.

In the embodiments described above, the electromagnetic actuator 100 of the present disclosure is used for the on-off two-way electromagnetic valve 200, but the electromagnetic actuator 100 can also be used for the three-way electromagnetic valve 200 as shown in FIG. The three-way valve includes two outflow passages, a first outflow passage 2220 and a second outflow passage 2221, for one inflow passage 221.

When the coil 102 of the electromagnetic actuator 100 is not energized, it is displaced in the first direction by the biasing force of the plunger spring 140, as described above. Therefore, the valve body 230 is removed from the first valve seat 2270 and is seated on the second valve seat 2271. Therefore, the first outflow passage 2220 becomes a normally open outflow passage, and the second outflow passage 2221 becomes a normally closed outflow passage.

FIG. 7 shows an example in which the electromagnetic valve 200 consisting of the three-way valve shown in FIG. 6 is connected to the piping 10 and the camera piping 12. Which of the first outflow passage 2220, which is a normally open outflow passage, and the second outflow passage 2221, which is a normally closed outflow passage, is used for the rear window glass 13 and which one is used for the camera 15 can be selected as appropriate depending on the design. .

When the first outflow passage 2220, which is a normally open outflow passage, is used in the rear window glass 13, when the washer fluid is to be ejected to the camera 15, the coil 102 is energized and excited. As described above, the plunger 130 is attracted in the second direction, and the valve body 230 is seated on the first valve seat 2270 and separated from the second valve seat 2271 under the urging force of the valve spring 233. As a result, the second outflow passage 2221, which is a normally closed outflow passage, is opened, and the high-pressure washer fluid from the pump 17 flows into the camera piping 12.

In the examples shown in FIGS. 2 and 3, the magnetic constriction portion 112 is formed of a thin portion. Thereby, the stator core 110 can be obtained in which the first cylindrical portion 117 and the second cylindrical portion 118 are integrated. The inner and outer diameters of the components of the electromagnetic actuator 100 can be increased by the thickness of the sleeve 119 shown in FIG. 4, and the volume of the plunger can also be increased. As a result, the amount of magnetic flux flowing through the plunger 130 can be increased, and in turn, the attractive force of the plunger 130 can be increased.

Furthermore, by providing the magnetic constriction part 112 made of a thin wall part in the stator core 110, the magnetic constriction part made of a non-magnetic space that exists when the first cylindrical part 117 and the second cylindrical part 118 shown in FIG. 4 are separate parts. It replaces 112. This allows the magnetic flux of the plunger 130 to be moved, and by changing the dimensions of the thin wall portion, it is possible to adjust the attraction force characteristics according to the required stroke and performance.

In this way, the magnetic constriction section 112 made of a thin wall portion in this example has many advantages compared to the magnetic constriction section 112 made of a non-magnetic space. However, the present disclosure does not exclude the magnetic constriction section 112 that is a non-magnetic space. It is possible to use the sleeve 119 if necessary.

In the example described above, the electromagnetic actuator 100 of the present disclosure was used together with the valve section 201 as the electromagnetic valve 200, but the electromagnetic actuator 100 of the present disclosure has various uses other than the electromagnetic valve 200. It can also be used to switch between locking and unlocking a member, or adjusting the angle of a member.

Further, the materials and sizes described above are merely examples, and can be appropriately selected depending on the required performance. The disclosure in this specification, drawings, etc. is not limited to the illustrated embodiments. The disclosure includes the illustrated embodiments and variations thereon by those skilled in the art.

100 Electromagnetic actuator 102 Coil 110 Stator core 113 Stepped portion 114 Stator taper portion 130 Plunger 131 Plunger shoulder portion 132 Plunger taper portion 133 Ring-shaped magnetic concentration portion 134 Recessed portion 140 Plunger spring

Claims (5)

A coil that is excited when energized,
A stator core made of a magnetic material, which is arranged in a magnetic circuit when the coil is energized, and has a magnetic constriction part;
a plunger made of a magnetic material and disposed opposite to the stator core across a magnetic gap in the magnetic circuit when the coil is energized;
a plunger spring that urges the plunger in a first direction away from the stator core;
The stator core has a cylindrical shape, and a stepped portion bent radially inward is formed at a position a predetermined distance away from the magnetic constriction portion in a second direction opposite to the first direction on the inner circumference thereof. At the same time, the inner peripheral portion forms a stator tapered portion whose diameter gradually decreases in the second direction from the stepped portion,
The plunger has a cylindrical shape, and has a plunger shoulder opposite to the stepped portion on its outer periphery, and the outer periphery has a stator tapered portion whose diameter extends from the plunger shoulder toward the second direction. A plunger taper portion that gradually decreases at approximately the same inclination angle is formed, a ring-shaped magnetic concentration portion is formed at the tip of the plunger taper portion in the second direction, and a radially inner side of the ring-shaped magnetic concentration portion is formed at the tip of the plunger taper portion in the second direction. An electromagnetic actuator characterized in that a recessed portion is formed in one direction. The electromagnetic actuator according to claim 1, wherein the magnetic constriction portion is formed as a thin wall portion of the stator core. The electromagnetic actuator according to claim 1 or 2, wherein a washer made of a non-magnetic material is disposed on either the stepped portion or the plunger shoulder. Any one of claims 1 to 3, wherein a second stepped portion facing the ring-shaped magnetic concentration portion of the plunger is formed on the second direction side of the stator taper portion of the stator core. The electromagnetic actuator described in . a valve body;
a valve spring that biases the valve body in the second direction;
The valve body further includes a working fluid inflow passage, a working fluid outflow passage, and a valve seat formed between the inflow passage and the outflow passage and against which the valve body abuts,
Any one of claims 1 to 4, wherein the plunger moves in the second direction when the coil is energized, so that the valve body moves in the second direction under the urging force of the valve spring. The electromagnetic actuator described in .

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