JP3157218U - solenoid valve - Google Patents

Abstract

An electromagnetic valve that effectively reduces annoying noise generated when a movable iron core is magnetically attracted to a fixed iron core without hindering miniaturization and low power consumption of the electromagnetic valve. An electromagnetic coil, a fixed iron core excited by energizing the electromagnetic coil, a movable iron core excited by energizing the electromagnetic coil and magnetically attracted to the fixed iron core, and an electromagnetic coil. The yoke 6 which forms a magnetic circuit together with the fixed iron core 3 and the movable iron core 4 is arranged outside, the valve body 41 which is attached to the movable iron core 4 and is separated from the valve seat 15, and the movable iron core 4 is fixed to the fixed iron core 3. In the electromagnetic valve including the spring 5 that is biased in the direction away from the movable core 4, the sum of the masses of the movable iron core 4 and the valve body 41 is smaller than the mass of the fixed iron core 3. By magnetically adsorbing to the fixed iron core 3, the impact applied to the fixed iron core 3 is suppressed. [Selection] Figure 1

Description

  The present invention relates to an electromagnetic valve that opens and closes a flow path used in a fluid control unit such as a warm water washing toilet seat, and particularly relates to an electromagnetic valve that reduces impact noise caused by a collision between a fixed iron core and a movable iron core.

  For example, a solenoid valve having a structure as shown in FIG. 5 is known. The solenoid valve 100 includes a body 101 having an introduction port 101a, a lead-out port 101b, and a valve hole 101c in the middle thereof, a fixed iron core (center post) 103 fixedly disposed on the inner periphery of the electromagnetic coil 102, and the fixed A movable iron core (plunger) 104 that is arranged concentrically with the iron core 103 and is capable of reciprocating in the axial direction, and a valve body 105 made of a rubber-like elastic material attached to an end of the movable iron core 104 opposite to the fixed iron core 103; A spring 106 arranged between the fixed iron core 103 and the movable iron core 104, and a yoke 107 arranged outside the electromagnetic coil 102 and in contact with the outer end of the fixed iron core 103. As the movable iron core 104 reciprocates due to energization / disconnection, the valve body 105 comes into contact with the valve seat 101d around the valve hole 101c and comes into contact therewith. To open or close the hole 101c (for example, see Patent Documents 1 to 3 below).

  In this type of solenoid valve 100, a magnetic circuit passing through the fixed iron core 103, the movable iron core 104 and the yoke 107 is formed by energization of the electromagnetic coil 102, and the movable iron core 104 resists the urging force of the spring 106. When the magnet is magnetically attracted, shock vibration due to the collision occurs. Since this shock vibration is transmitted from the fixed iron core 103 to the yoke 107 and the body 101, there is a problem that annoying noise is radiated to the outside.

  Moreover, in this type of solenoid valve 100, the dimensional relationship between the movable iron core 104 and the fixed iron core 103 is normally such that the movable iron core 104 and the fixed iron core 103 are in the most separated state by disconnecting the electromagnetic coil 102. It is most well-balanced to design the gap G between the magnetic core 102 and the fixed iron core 103 so that it is positioned at the center of the axial length of the electromagnetic coil 102. In this design, the mass of the movable iron core 104 is fixed. Therefore, there is a problem that the impact force when the movable iron core 104 is attracted to the fixed iron core 103 by energization of the electromagnetic coil 102 is large and the generated noise becomes large.

  Therefore, conventionally, in order to suppress such noise, a buffer body made of a nonmagnetic rubber-like elastic material or the like is provided between the fixed iron core 103 and the movable iron core 104 to avoid direct collision between metal surfaces. It is known to prevent impact noise (see, for example, Patent Document 4 below).

JP 2008-223921A Japanese Patent No. 3746838 JP 2005-172151 A JP 2002-276840 A

  However, such a technique is effective for a normal solenoid valve that applies a constant voltage to the electromagnetic coil 102, but in a state where the movable iron core 104 is magnetically attracted to the fixed iron core 103, the movable iron core 104 and the fixed iron core 103 are used. Since a nonmagnetic buffer is interposed between the two, a reduction in magnetic attractive force with respect to the movable iron core 104 is inevitable. Therefore, variable control for the purpose of recent miniaturization and power saving, for example, PWM (Pulse Width Modulation) control that modulates the pulse width according to the level of the input signal at a constant period, and duty that controls the duty ratio of the current In the case where the power consumption is reduced by the control, the movable iron core 104 may be detached from the fixed iron core 103 due to the urging force of the spring 106 when the applied pulse is OFF, or may be closed even if it is not detached. There has been a problem that 104 is oscillated by a pulsed magnetic field and is likely to generate a beat sound.

  Therefore, as described in Patent Document 4, in the method of interposing a buffer between the fixed core 103 and the movable core 104, it is difficult to reduce the size of the solenoid valve, and it is essential to apply a constant voltage. It was difficult to adopt in an environment where power consumption was required.

  The present invention has been made in view of the above points, and its technical problem is that the movable iron core is magnetically attracted to the fixed iron core without hindering the miniaturization and low power consumption of the solenoid valve. It is to effectively reduce the annoying noise that occurs during the process.

  As means for effectively solving the technical problem described above, an electromagnetic valve according to claim 1 includes an electromagnetic coil, a fixed iron core excited by energization of the electromagnetic coil, and energization of the electromagnetic coil. A movable iron core that is excited by the magnetic core and is magnetically attracted to the fixed iron core, a yoke that is arranged outside the electromagnetic coil and forms a magnetic circuit with the fixed iron core and the movable iron core, and a valve seat that is attached to the movable iron core and separated from the valve seat. In a solenoid valve comprising a valve body to be contacted and a spring that biases the movable core away from the fixed core, the sum of the mass of the movable core and the valve body is smaller than the mass of the fixed core. It is a feature.

  The operation sound of the electromagnetic valve is generated by the collision of the movable iron core with the fixed iron core, and the impact is radiated by propagating from the fixed iron core to the external components of the electromagnetic valve. According to the valve, since the sum of the mass of the movable core and the valve body is smaller than the mass of the fixed core, the impact applied to the fixed core when the movable core is magnetically attracted to the fixed core when the exciting current is applied to the electromagnetic coil Is suppressed.

  According to a second aspect of the present invention, there is provided the electromagnetic valve according to the first aspect, wherein the holding hole for holding the spring is recessed in the end surface of the movable core on the fixed core side, and the electromagnetic coil is disconnected. Sometimes when the movable iron core is most separated from the fixed iron core, the end surface on the fixed iron core side of the movable iron core is closer to the fixed iron core than the surface on the fixed iron core side at the end of the yoke facing the outer diameter surface of the movable iron core And the bottom portion of the holding hole is substantially flush with the surface on the fixed iron core side at the end of the yoke.

  According to the electromagnetic valve of the second aspect of the invention, in the state where the movable core is most separated from the fixed core, the end surface of the yoke facing the outer diameter surface of the movable core is the end surface on the fixed core side of the movable core. Because it is located on the fixed iron core side than the surface on the fixed iron core side in the magnetic coil, in the energized state of the excitation current to the electromagnetic coil, a good magnetic circuit is formed via the fixed iron core, the movable iron core, and the yoke. The fixed iron core is held in an attracted state by a strong magnetic force. Therefore, even when the applied voltage is subjected to PWM control or duty control, the movable iron core does not separate from the fixed iron core or generate a beat sound due to the biasing force of the spring.

  According to a third aspect of the present invention, there is provided the electromagnetic valve according to the first aspect, wherein the holding hole for holding the spring is recessed in the end surface on the movable core side of the fixed iron core, and the electromagnetic coil is disconnected. Sometimes when the movable core is most separated from the fixed core, the end surface on the fixed core side of the movable core is substantially flush with the surface on the fixed core side at the end of the yoke facing the outer diameter surface of the movable core. It is characterized by this.

  According to the electromagnetic valve according to the third aspect of the invention, the mass of the movable iron core is smaller than that of the configuration of the second aspect, so that the movable iron core is magnetically attracted to the fixed iron core when the exciting current is supplied to the electromagnetic coil. The impact given to the fixed iron core is further suppressed. In addition, since the holding hole for holding the spring is recessed in the end surface on the movable iron core side of the fixed iron core, the end surface on the fixed iron core side of the movable iron core is moved in this state when the movable iron core is most separated from the fixed iron core. Even if it is substantially flush with the surface on the fixed core side at the end of the yoke facing the outer diameter surface of the iron core, good magnetism through the fixed iron core, the movable iron core and the yoke in the energized state of the exciting current to the electromagnetic coil A circuit is formed, and the movable iron core and the fixed iron core are held in an attracted state by a strong magnetic force. Therefore, even when the applied voltage is subjected to PWM control or duty control, the movable iron core does not separate from the fixed iron core or generate a beat sound due to the biasing force of the spring.

  According to the electromagnetic valve according to the present invention, the shock applied to the fixed iron core is reduced by the magnetic core being magnetically attracted to the fixed iron core, so that an electromagnetic wave is interposed between the fixed iron core and the movable iron core. The disturbing noise can be effectively reduced without hindering the downsizing of the valve and the reduction in power consumption.

It is sectional drawing which shows the 1st form of the solenoid valve which concerns on this invention. It is explanatory drawing which shows the effect | action by a 1st form. It is sectional drawing which shows the 2nd form of the solenoid valve which concerns on this invention. It is explanatory drawing which shows the effect | action by a 2nd form. It is sectional drawing which shows an example of the solenoid valve which concerns on a prior art.

  Hereinafter, embodiments of a solenoid valve according to the present invention will be described with reference to the drawings. First, FIG. 1 is a cross-sectional view showing a first embodiment of the electromagnetic valve according to the present invention, and FIG. 2 is an explanatory view showing the operation of this embodiment.

  The electromagnetic valve shown in FIG. 1 includes a body 1, an electromagnetic coil 2, a fixed iron core 3 fixedly disposed on the inner periphery of the electromagnetic coil 2, and a fixed iron core 3 concentric with the inner periphery of the electromagnetic coil 2. A movable iron core 4 which is axially reciprocable and has a valve body 41 attached thereto, a spring 5 arranged between the fixed iron core 3 and the movable iron core 4, and a yoke arranged outside the electromagnetic coil 2. 6.

  The body 1 includes a valve chamber 11, an introduction port 12 for introducing a fluid into the valve chamber 11, a lead-out port 13 for leading the fluid out of the valve chamber 11, and the valve chamber 11 and the lead-out port 13. It has an opened valve hole 14, a tapered cylindrical valve seat 15 formed along an opening on the valve chamber 11 side in the valve hole 14, and an annular mounting portion 16 surrounding the valve chamber 11. .

  The electromagnetic coil 2 is connected to a bobbin 21 concentrically attached to the body 1 with the valve seat 15 in a state where one end 21a is inserted into the inner periphery of the annular mounting portion 16 in the body 1 via an O-ring 23. The coil body 22 is wound and the outer periphery is covered with a mold 24, and both ends of the coil body 22 are connected to terminals 25 and 26.

  The fixed iron core 3 has a cylindrical shape and is excited by energization of the electromagnetic coil 2 (coil body 22). The fixed iron core 3 is inserted into the inner periphery of the bobbin 21 through the O-ring 31 and the outer end 3a is a yoke. 6, the inner end 3b extends from the intermediate position in the axial direction of the coil body 22 of the electromagnetic coil 2 to the body 1 side.

  The movable iron core 4 also has a cylindrical shape, is excited by energization of the electromagnetic coil 2 (coil body 22), and is magnetically attracted to the fixed iron core 3, and is formed on the inner periphery of one end 21a of the bobbin 21 in the electromagnetic coil 2. It is loosely inserted so as to be capable of reciprocating in the axial direction.

  The valve body 41 is made of a rubber-like elastic material, and the outer peripheral portion thereof is caulked and fixed to the end portion 4c of the movable iron core 4 opposite to the fixed iron core 3, and the inner periphery of the opening of the one end 21a of the bobbin 21 in the electromagnetic coil 2 is fixed. It faces to the valve seat 15 in the body 1 so as to be detachable.

  The axial length of the movable iron core 4 is sufficiently shorter than the axial length of the fixed iron core 3. For this reason, the sum of the masses of the movable iron core 4 and the valve body 41 is sufficiently smaller than the mass of the fixed iron core 3. ing.

  The spring 5 is a metal coil spring, and is held in a holding hole 4a recessed in the end surface 4b opposite to the valve body 41 in the movable iron core 4, and the bottom of the holding hole 4a and the fixed iron core 3 are held. By being arranged in an appropriately compressed state between the inner end portion 3b of the main body and the inner end portion 3b, the movable core 4 is always urged in a direction in which the movable core 4 is pulled away from the fixed core 3, in other words, in a direction in which the valve body 41 is pressed against the valve seat 15. Yes.

  The yoke 6 forms a magnetic circuit together with the fixed iron core 3 and the movable iron core 4 by energization of the electromagnetic coil 2 (coil body 22). The yoke 6 has a substantially U-shaped bent shape, and one end 61 is the electromagnetic coil 2. Is positioned and fixed between the bobbin 21 and the mounting portion 16 of the body 1, is opposed to the outer diameter surface 4 d of the movable iron core 4 in the radial direction, and the other end 62 is the body 1 in the bobbin 21. It extends to the end on the opposite side to the outer end 3 a of the fixed iron core 3.

  Further, when the movable iron core 4 is most separated from the fixed iron core 3 by the biasing force of the spring 5 when the electromagnetic coil 2 (coil body 22) is disconnected, the end surface 4b of the movable iron core 4 on the fixed iron core 3 side is movable. The bottom portion of the holding hole 4a that holds the spring 5 and is positioned on the fixed iron core 3 side of the surface 61a on the fixed iron core 3 side in the one end portion 61 of the yoke 6 that faces the outer diameter surface 4d of the iron core 4 in the radial direction. 1 is substantially flush with the surface 61a on the fixed iron core 3 side of the one end 61 of the yoke 6, as indicated by a one-dot chain line in FIG.

  One end of the yoke 6 in a state where the movable iron core 4 is most separated from the fixed iron core 3 by the biasing force of the spring 5 when the electromagnetic coil 2 (coil body 22) is deenergized at the depth d of the holding hole 4a. The height of the end surface 4b of the movable iron core 4 from the surface 61a on the fixed iron core 3 side in the portion 61 is about 3 mm in actual size, and the gap G between the fixed iron core 3 and the movable iron core 4 at this time is 0 in actual size. It is set to be about 5 mm.

  The electromagnetic valve according to the first embodiment having the above-described configuration is used in, for example, a water injection device for a warm water washing toilet seat, and the movable iron core 4 is fixed by the biasing force of the spring 5 when the electromagnetic coil 2 is disconnected. A valve element 41 pushed out toward the direction away from the iron core 3, in other words, toward the valve seat 15 and held by the movable iron core 4 is in close contact with the valve seat 15. For this reason, as shown in FIG. 1, the valve hole 14 is normally closed.

  At this time, the pressure of the cleaning water introduced into the valve chamber 11 from the introduction port 12 acts on the movable iron core 4 and the valve body 41 in the valve opening direction on the outer peripheral side of the valve seat 15. The surface opposite to the valve element 41 in the movable iron core 4 acts in the valve closing direction, and since the pressure receiving area is larger, the valve is not inadvertently opened due to the pressure of the washing water.

  When the electromagnetic coil 2 (coil body 22) is energized, the fixed iron core 3 and the movable iron core 4 are magnetized by the magnetic field generated in the electromagnetic coil 2, and pass through the yoke 6 as shown by the broken line in FIG. Therefore, the movable iron core 4 overcomes the closing force due to the urging force of the spring 5 and the pressure of the cleaning water in the valve chamber 11 by the magnetic force acting between the fixed iron core 3 and the movable iron core 4. It is displaced toward the fixed iron core 3 and is adsorbed by the fixed iron core 3. For this reason, the valve element 41 held by the movable iron core 4 is separated from the valve seat 15 and the valve hole 14 is opened to open the valve, and the cleaning water is supplied from the introduction port 12 to the valve chamber 11, the valve element 41 and the valve. It is sent to the outlet port 13 between the seats 15 and via the valve holes 14.

  In this valve opening operation, the movable iron core 4 is attracted to and collides with the fixed iron core 3, and an impact is generated. However, the sum of the masses of the movable iron core 4 and the valve body 41 is sufficiently larger than the mass of the fixed iron core 3. In other words, since the mass of the fixed iron core 3 is sufficiently larger than the sum of the mass of the movable iron core 4 and the valve body 41, the impact applied to the fixed iron core 3 can be kept small. Therefore, since the shock vibration is propagated from the fixed iron core 3 to the yoke 6, it is possible to remarkably reduce the annoying impact sound radiated from the yoke 6 to the outside.

  In addition, since the movable iron core 4 is directly adsorbed to the fixed iron core 3 when the electromagnetic coil 2 is energized, the movable iron core 4 and the fixed iron core 3 are held in an adsorbed state by a strong magnetic force. In particular, when the movable iron core 4 is most separated from the fixed iron core 3 when the electromagnetic coil 2 is disconnected, the end surface 4b on the fixed iron core 3 side of the movable iron core 4 is the surface on the fixed iron core 3 side at the one end portion 61 of the yoke 6. Since the electromagnetic coil 2 shown in FIG. 2 is positioned closer to the fixed iron core 3 than 61a, the magnetic flux H is not short-circuited to the fixed iron core 3 without passing through the movable iron core 4, In addition, the bottom of the holding hole 4a for holding the spring 5 is substantially flush with the surface 61a on the fixed iron core 3 side at the one end 61 of the yoke 6 when the electromagnetic coil 2 is disconnected. A part Ha of H is formed between the one end 61 of the yoke 6 and the outer periphery of the holding hole 4a so as to wrap around the bottom side of the holding hole 4a. Iron core 3 is due to strong magnetic force Wearing state is maintained. Therefore, even when the applied voltage is PWM-controlled or duty-controlled, the movable iron core 4 may be disengaged from the fixed iron core 3 due to the urging force of the spring 5, and may be inadvertently closed, or a beeping sound may be generated. Can be prevented.

  Therefore, according to the above configuration, it is possible to perform PWM control or duty control of the applied voltage for miniaturization and low power consumption of the solenoid valve, which hinders miniaturization and low power consumption of the solenoid valve. Therefore, it is possible to effectively reduce annoying noise.

  FIG. 3 is a cross-sectional view showing a second embodiment of the electromagnetic valve according to the present invention, and FIG. 4 is an explanatory view showing the operation of this embodiment. In this embodiment, the difference from the first embodiment described above is that the spring 5 is held in a holding hole 3c that is recessed in the end 3b of the fixed iron core 3 on the movable iron core 4 side, and the electromagnetic coil 2 When the movable core 4 is most separated from the fixed core 3 by the urging force of the spring 5 when the (coil body 22) is disconnected, the end surface 4b on the fixed core 3 side of the movable core 4 is the outer diameter of the movable core 4. The one end 61 of the yoke 6 facing the surface is substantially flush with the surface 61a on the fixed iron core 3 side. Other configurations are basically the same as those in FIG.

  According to this configuration, the holding hole for holding the spring 5 is not recessed in the movable iron core 4, and the end surface 4 b on the fixed iron core 3 side of the movable iron core 4 is disconnected from the yoke 6 when the electromagnetic coil 2 is disconnected. By being substantially flush with the surface 61a on the fixed iron core 3 side at the one end 61, the axial length of the movable iron core 4 is further shortened, as can be seen from comparison with FIG. The axial length of the stationary iron core 3 is further increased and the mass is increased, so that when the electromagnetic coil 2 is energized, the movable iron core 4 is magnetically attracted to and collides with the stationary iron core 3. The impact applied to the fixed iron core 3 is further suppressed. Therefore, since the shock vibration is propagated from the fixed iron core 3 to the yoke 6, the annoying impact sound radiated from the yoke 6 to the outside can be remarkably reduced.

  Further, since the holding hole 3c for holding the spring 5 is recessed in the fixed iron core 3 and there is no holding hole in the movable iron core 4, when the electromagnetic coil 2 is energized, as shown in FIG. The magnetic flux H passing through the movable iron core 4 is not hindered between the one end portion 61 and the fixed iron core 3, and the movable iron core 4 and the fixed iron core 3 are held in an attracted state by a strong magnetic force. Therefore, even when the applied voltage is PWM-controlled or duty-controlled, the movable iron core 4 may be disengaged from the fixed iron core 3 due to the urging force of the spring 5, and may be inadvertently closed, or a beeping sound may be generated. Can be prevented.

DESCRIPTION OF SYMBOLS 1 Body 14 Valve hole 15 Valve seat 2 Electromagnetic coil 21 Bobbin 3 Fixed iron core 4 Movable iron core 41 Valve body 5 Spring 6 Yoke

Claims (3)

  An electromagnetic coil, a fixed iron core excited by energization of the electromagnetic coil, a movable iron core excited by energization of the electromagnetic coil and magnetically attracted to the fixed iron core, and disposed outside the electromagnetic coil and fixed An electromagnetic comprising a yoke that forms a magnetic circuit together with the iron core and the movable iron core, a valve body that is attached to the movable iron core and that is separated from and attached to the valve seat, and a spring that biases the movable iron core in a direction away from the fixed iron core In the valve, the sum of the mass of the movable iron core and the valve body is smaller than the mass of the fixed iron core.   A holding hole for holding a spring is recessed in the end surface on the fixed core side of the movable core, and the end surface on the fixed core side in the movable core when the movable core is most separated from the fixed core when the electromagnetic coil is disconnected Is positioned closer to the fixed core than the surface on the side of the fixed core at the end of the yoke facing the outer diameter surface of the movable core, and the bottom of the holding hole is the surface on the side of the fixed core at the end of the yoke The electromagnetic valve according to claim 1, wherein the electromagnetic valve is substantially flush.   A holding hole for holding the spring is recessed in the end surface on the movable core side of the fixed core, and the end surface on the fixed core side in the movable core when the movable core is most separated from the fixed core when the electromagnetic coil is disconnected The electromagnetic valve according to claim 1, wherein the electromagnetic valve is substantially flush with a surface on the fixed iron core side at an end of the yoke facing the outer diameter surface of the movable iron core.

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