JP2009209974A - Diaphragm type solenoid valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a diaphragm type solenoid valve that prevents malfunction even when the fluid flowing inside contains moisture and the moisture is likely to freeze when used in a cold district or the like.
SOLUTION: A valve seat 2 provided between a first port 11 and a second port 12 through which fluid flows and a main valve 1a are provided. 100 is a diaphragm type electromagnetic valve that includes a diaphragm valve 1 that can be shut off, a movable iron core 3 that is movable in the axial direction, and a solenoid coil 4 that is disposed around the movable iron core 3 and operates the movable iron core 3 by excitation. In this case, the main valve 1a is provided directly on the movable iron core 3, and when the movable iron core 3 is operated, heat generated in the correnoid coil 4 is transmitted to the main valve 1a, so that the valve seat periphery is frozen. It was set as the structure which can be thawed | decompressed efficiently.
[Selection] Figure 1

Description

  The present invention relates to a diaphragm type solenoid valve, and more particularly to a diaphragm type solenoid valve that can be thawed and used efficiently even when water droplets adhere to the valve seat of the diaphragm type solenoid valve and freezes. It is.

  Usually, an electromagnetic valve is installed between two ports of a flow path through which gas or the like is circulated, and is used when the flow rate of gas or the like is controlled. In particular, the diaphragm type solenoid valve is an effective solenoid valve in order to prevent gas from entering the drive portion where the movable iron core slides. When such a diaphragm type solenoid valve is used in a fuel cell system, it is used to control the flow rate of the reaction gas or off gas. Moisture is contained in the reaction gas or off-gas flowing through the fuel cell system. In this case, when the power generation of the fuel cell system is stopped, the temperature of the reaction gas or off-gas decreases, and with this temperature decrease, condensation may occur in the flow path through which the gas of the solenoid valve flows, and water or water droplets may accumulate. . Therefore, when the fuel cell system is used under a low temperature condition in a cold region, it is possible that water or water droplets accumulated inside freeze.

For example, in Patent Document 1, a diaphragm is disposed between a solenoid portion disposed inside a casing and a second valve body into which a reaction gas (hydrogen) is introduced, and A fuel cell in which a valve body is provided at an upper end portion of a shaft that is displaced along the axial direction under the excitation action of the solenoid portion, and first and second elastic members made of an elastic material are mounted on the upper and lower surfaces of the valve body, respectively. An electromagnetic valve is disclosed. With such a solenoid valve, the water generated in the solenoid valve does not enter the solenoid part where the movable core moves due to the diaphragm, but on the shaft that is displaced along the axial direction under the excitation action of the solenoid part. Moisture will not adhere.
JP 2004-179118 A (pages 1 to 5)

  With the electromagnetic valve disclosed in Patent Document 1, it is possible to suppress water from entering the solenoid part where the movable core moves and adhesion of moisture to the shaft. However, a valve body and a valve seat are provided at the upper end of the shaft. If water adheres to the valve body, the water adhering to the valve seat freezes when used in a low temperature state where the temperature is zero degrees or less. As a result, if the water adhering to the valve seat freezes, it becomes difficult to separate the valve body from the valve seat, even if the solenoid coil is energized and the solenoid valve is operated. There is a risk that.

  Therefore, the present invention has been made in view of the above-described problems, and even if the fluid flowing inside contains moisture, and the moisture easily freezes in use in a cold district or the like, the problem is prevented. An object of the present invention is to provide a diaphragm type solenoid valve.

  The technical means taken in order to solve the above-described problem includes a valve seat provided between a first port and a second port through which a fluid flows, and a main valve, and the main valve is separated from the valve seat. A diaphragm comprising: a diaphragm valve capable of blocking between the two ports by contact; a movable iron core that is movable in the axial direction; and a solenoid coil that is disposed around the movable iron core and operates the movable iron core by excitation. In this type of solenoid valve, the main valve is provided directly on the movable iron core, and heat generated in the correnoid coil is transmitted to the main valve when the movable iron core is operated.

  In this case, it is preferable that a concave portion is formed in the movable iron core and a main valve is attached to the concave portion.

  The main valve may be larger than the outer shape of the valve seat.

  Furthermore, the outer shape of the valve seat should be smaller toward the diaphragm valve.

  According to the technical means, when operating the diaphragm type solenoid valve, if the solenoid coil is energized from the outside, the solenoid coil generates heat due to the energization, and the generated heat passes through the movable iron core. Is transmitted directly to the main valve. Therefore, the heat generated by the solenoid coil transmitted through the movable iron core is efficiently transmitted to the contact part between the main valve and the valve seat, and the temperature of the main valve, valve seat and the contact part is efficiently raised. Can be made. As a result, when such a solenoid valve is used in a cold district where the ambient temperature is below zero degrees, water flowing from the fluid inside the solenoid valve or water or water droplets generated from the fluid may become trapped between the main valve and the valve seat. Even if it freezes, the heat generated by the solenoid coil can be used to efficiently raise the temperature of the main valve, the valve seat, and the contacted part and defrost. Inconveniences such as failure to achieve desired performance can be prevented.

  In this case, the movable iron core is formed with a recess, and the main valve is attached to the recess, thereby preventing problems such as the desired performance not being achieved when used in cold regions, etc., with a very simple configuration. can do.

  Further, if the main valve is larger than the outer shape of the valve seat, the heat transfer efficiency is good and the conventional problems can be prevented.

  Furthermore, by reducing the outer shape of the valve seat toward the diaphragm valve, it is possible to further reduce the area where the main valve that shuts off the ports contacts the valve seat. For this reason, the temperature of the contact portion between the main valve and the valve seat is efficiently raised, and even if the main valve and the valve seat are frozen, the force for separating the main valve from the valve seat can be reduced. Therefore, the diaphragm type solenoid valve can be miniaturized.

  Hereinafter, an embodiment of the present invention will be described with reference to FIG.

  A diaphragm solenoid valve (hereinafter simply referred to as a solenoid valve) 100 according to the present invention mainly includes a first body 10, a second body 14, a diaphragm valve 1, a movable iron core 3, a fixed iron core 8, and an urging force. A member 5 and a solenoid coil 4, a cylindrical guide 6, and a plate 13 are provided. The urging member 5 and the solenoid coil 4 constitute a drive unit that moves the movable iron core 3 in the axial direction.

  The first body 10 is formed using a metal or a resin material as a base material, and has a valve seat 2 and a valve port 21 that are cylindrical in a hollow chamber 101 through which a fluid (gas or liquid) flows. The valve seat 2 has a seating portion 2c at the upper end and protrudes toward the diaphragm valve 1 (upward in FIG. 1). The outer end of the valve seat 2 is gradually narrowed toward the diaphragm valve 1. By reducing the outer shape of the tip in this way, the area of the seating portion 2c that comes into contact with the main valve 1a of the diaphragm valve 1 described later is reduced. As a result, when the solenoid valve 100 is used in a cold district where the ambient air temperature is less than or equal to zero degrees, thawing becomes easier when the seat 2c and the main valve 1a are in contact with each other and frozen. Can be easily separated. Further, in the first body 10, a circular first port (which serves as a gas flow path inlet) 11 is provided upstream of the valve port 21, and a circular second port (gas) is provided downstream of the valve port 21. 12 which becomes a channel outlet) is provided. The diameter of the valve port 21 is set to be thinner and smaller than the diameter of the second port 12. Thus, by setting the diameter of the valve port 21 to be smaller and smaller than the diameter of the gas flow path outlet 12, the fluid flowing between the ports can be surely cut off, and the flow rate control of the fluid can be facilitated. .

  The second body 14 having the solenoid coil 4 wound around the bobbin 7 is attached to the first body 10. In this case, the guide portion 6 having the flange-shaped fixing portion 6 a is connected to the first body 10 and the first body 10. An annular plate 13 that is sandwiched and fixed by two bodies 14 is disposed therebetween. The plate 13 is made of a metal material having good heat conduction. In this embodiment, for example, cast steel is used. A hole 13a for supporting the cylindrical guide 6 is formed in the plate 13, and the guide 6 is inserted through the hole 13a.

  In the hollow chamber 101 formed in the first body 10, the center lines of the first port 11 and the second port 12 are formed 90 degrees perpendicular to each other, and the valve seat 2 is seen from the second port side. It protrudes toward the movable iron core 3 in the hollow chamber, and has an inclined surface 102 inside as shown in FIG. By providing the inclined surface 102 inside the first body 10 in this way, the fluid introduced from the first port 11 is directed to the valve port 21 along the inclined surface 102, so that from the hollow chamber 101 to the valve port 21. The pressure loss between the two can be suppressed and the fluid can flow efficiently.

  The guide 6 is made of stainless steel (a material that is nonmagnetic and has good electrical insulation) as a base material, and is fixed in a radial direction that is sandwiched and fixed between the plate 13 and the first body 10. A portion 6a and a sliding portion 6c that fits into the hole 13a of the plate 13 and has a continuous cylindrical shape from the inner peripheral portion of the fixed portion 6a and serves as a guide when the movable iron core 3 slides are provided. A cylindrical space 62 is formed by the inner peripheral wall surface of the sliding portion 6 c of the guide 6. The movable iron core 3 is slidably accommodated in the space 62. The plate 13 and the first body 10 are fastened together with the second body 14 by a fastening member such as a bolt (not shown) or caulking.

  The movable iron core 3 has a bottomed cylindrical shape, and the urging member 5 is disposed inside the cylinder on the side where the fixed iron core 8 is provided. For example, a coil spring arranged coaxially with the movable iron core 3 can be used as the urging member 5, and a biasing force that urges the movable iron core 3 in the valve closing direction (downward in FIG. 1) is applied. The movable iron core 3 is formed of a material that can transmit magnetic flux. In this embodiment, electromagnetic stainless steel is used in consideration of durability. However, carbon steel, cast steel, or the like may be used as other materials. it can. Opposed to the movable iron core 3 is a cylindrical fixed iron core 8 that is coaxial with the movable iron core 3. One end 5 a of the urging member 5 is locked to the bottom surface of the recess formed in the center of the movable core 3, and the other end 5 c is locked to the bottom surface 8 a of the recess formed in the fixed core 8. The fixed iron core 8 is formed of a material through which magnetic flux passes, and carbon steel is used in this embodiment.

  A solenoid coil 4 wound around a hollow cylindrical bobbin 7 is disposed on the outer periphery of the guide portion 6 and the fixed iron core 8. When the solenoid coil 4 is energized by external power supply, the solenoid coil 4 generates heat and is excited. With this excitation, the fixed iron core 8 is excited and attracts the movable iron core 3 toward the fixed iron core 8 against the urging force of the urging member 5. As a result, the movable iron core 3 moves in the valve opening direction. When the energization is stopped, the excitation of the solenoid coil 4 is eliminated, and accordingly, the excitation of the fixed iron core 8 is also eliminated, and the force for attracting the movable iron core 3 is lost. For this reason, the movable iron core 3 moves in the valve closing direction in contact with the valve seat 2 by the urging force of the urging member 5.

  The solenoid coil 4 is set so as to surround 70% or more of the axial length (full length) of the movable iron core 3 in a closed state as shown in FIG. By enclosing 70% or more, preferably 80% or more, of the total length of the movable iron core 3 with the solenoid coil 4, the heat generated in the solenoid coil 4 when the solenoid coil 4 is energized effectively becomes effective. Can be transmitted to.

  The diaphragm valve 1 is made of a member whose base material is a flexible material such as rubber or soft resin, and one side is attached to the recess (attachment surface) 3a of the movable iron core 3 and the other side abuts against the valve seat 2. Has a main valve 1a capable of shutting off the first port 11 and the second port 12 and shutting off the path of the fluid flowing therethrough, and has a convex portion 1b on the first body side. 101 is divided into two regions, and a seal portion 1c that seals the fluid flowing between the ports from leaking to the movable iron core 3 side is provided. In this embodiment, EPDM rubber (ethylene / propylene rubber) is used in consideration of flexibility at low temperatures. A convex portion provided on the opposite side of the main valve 1a that contacts the valve seat 2 is directly fitted in the concave portion 3 of the movable iron core 3, and the movable iron core 3 moves integrally with the diaphragm valve 1, and the seal portion 1c. Is fixed between the first body 10 and the fixed portion 6a of the guide portion 6 in the form of a flange. At this time, since the convex portion of the seal portion 1c is fixed by the fixing portion 6a of the guide portion 6 and the first body 10 in a state of being crushed by clamping, the fluid passes through the seal portion 1c from the gap of the first body 10 to the outside. Leakage can be prevented. Thus, the diaphragm valve 1 fixed to the guide portion 6 and the first body 10 partitions the hollow chamber 101 communicating with the valve port 21 and the cylindrical space 62 that houses the movable core 3, and the movable core 3 is a shaft. It is possible to reliably prevent the fluid from entering the space 62 that moves in the direction. Here, the size of the convex portion 1b in the radial direction is smaller than the diameter of the main body of the movable iron core 3, and is set to be at least the same size or slightly larger than the contact portion where the main valve 1a of the diaphragm valve 1 contacts the seat portion 2c. It is. Further, since the convex portion 1b of the main valve 1a is directly attached to the concave portion 3a of the movable iron core 3, heat can be efficiently transmitted from the movable iron core 3 to raise the temperature of the main valve 1. The method of attaching the main valve 1a to the recess 3a of the movable core 3 may be a method of directly fixing to the movable core 3 with an adhesive or the like, in addition to the method of forming the recess 3a and fixing by fitting. . Moreover, the method of directly adhering to the end surface of the movable iron core 3 in the axial direction with an adhesive may be used without forming the concave portion 3a on the movable iron core 3 side.

  By directly attaching the main valve 1a of the diaphragm valve 1 to the movable iron core 3 in this way, when the solenoid coil 4 is not energized, it contacts the seating portion 2c and closes the valve port 21, and the fluid flowing inside the first body The main valve 1a can be reliably heated by receiving heat directly from the movable iron core 3 by the heat generated by the solenoid coil 4.

  Next, the operation of this embodiment will be described.

  When the solenoid coil 4 is not energized from the outside, it is not excited, and the movable iron core 3 is urged in the valve closing direction by the urging force of the urging member 5 locked to the fixed iron core 8, and the main valve of the diaphragm valve 1. 1a contacts the seat 2c and shuts off the valve port 21. For this reason, the gas or liquid fluid flowing in from the first port 11 stays in the hollow chamber 101 and does not flow out from the second port 12. On the other hand, when the solenoid coil 4 is energized, it is excited by energization and attracts the movable iron core 3 to the fixed iron core side. As the movable iron core 3 moves, the main valve 1a moves away from the seating portion 2c and opens the valve port 21. As a result, the gas or liquid fluid flowing in from the first port 11 passes through the valve port 21 from the hollow chamber 101 and then flows out from the second port 12.

  For example, if the solenoid valve 100 described above is applied to a fuel cell system as an example, when the fluid flowing inside the first body 10 is a gas such as a reaction gas or an off-gas of the fuel cell, a lot of moisture is contained. Yes. For this reason, moisture contained in the gas adheres in the gas flow path. In this case, the valve seat 2 and the main valve 1a are maintained in a low temperature state where the ambient air temperature is less than or equal to zero degrees in a cold district or the like when the solenoid coil 4 is not energized (closed valve state) with moisture adhering to the seating portion 2c. When the water freezes due to the ambient temperature, the following problems occur. That is, the main valve 1a and the seating portion 2c of the valve seat 2 are in a state where they are difficult to be separated due to frozen moisture, and in some cases cannot be separated. In this case, in order to flow the gas from the first port 11 to the second port 12, it is necessary to thaw the frozen water near the valve seat. Therefore, in this embodiment, when the solenoid coil 4 is energized, the winding of the solenoid coil 4 generates heat due to the current. And the heat from this coil | winding is transmitted to the movable iron core 3 through the path | route shown below, and raises the temperature of the movable iron core 3 efficiently.

  The first path is transmitted to the movable iron core 3 through the bobbin 7 and the guide 6.

  The second path is transmitted from the bobbin 7 to the fixed core 8, and the heat of the fixed core 8 is transmitted to the movable core 3 through the urging member 5, and is also transmitted through the air layer between the fixed core 8 and the movable core 3. To the movable iron core 3.

  The third path transfers heat to the movable iron core 3 in the order of the bobbin 7, the second body 14, the plate 13, and the guide 6.

  Since the heat generated from the winding of the solenoid coil 4 is transmitted to the movable iron core 3 through the three paths described above, the temperature of the movable iron core 3 is increased efficiently. For this reason, the main valve 1a of the diaphragm valve 1 directly fitted in the recess 3a of the movable iron core 3 is heated by receiving heat from the movable iron core 3, and the freezing with the seating portion 2c is efficiently thawed. The valve 1a can be separated from the seating part 2c.

  Next, using the solenoid valve in the embodiment having the above-described configuration and the conventional diaphragm type solenoid valve, when the temperature of the solenoid valve is 30 degrees below zero, a voltage of 14, 5 V is applied to the solenoid coil, and then The temperature change of the main valve 1a when the energized state is continued is shown in FIG. As can be seen from FIG. 2, the solenoid valve 100 of this embodiment exceeds the temperature of 0 ° C. at which the temperature of the main valve 1a can be thawed 140 seconds after energization, but the conventional solenoid valve cannot be thawed without exceeding 20 degrees below zero. I understand that.

  As described above, the heat generated from the solenoid coil 4 by energizing the solenoid coil 4 is efficiently transmitted directly to the main valve 1a of the diaphragm valve 1 via the movable iron core 3, and the main valve 1a is efficiently transmitted. The temperature can be raised. Thereby, even when the electromagnetic valve 100 is used in a cold region or the like, thawing is performed even if the periphery of the valve seat 2 is frozen, and desired performance can be obtained.

  If the solenoid core 4 has a hollow space created by the valve in a closed state so that the length of the movable core 3 is 70% or more, the movable core 3 effectively collects the heat generated by the solenoid coil 4 and the diaphragm valve 1. Since heat is transferred to the main valve 1a, the temperature of the main valve 1a can be raised more efficiently.

  Furthermore, since the tip of the valve seat 2 is made smaller toward the diaphragm valve 1, the area of the seating portion 2c that comes into contact with the main valve 1a is reduced, so that the temperature rises easily, and the seating portion 2c and the main valve 1a. The main valve 1a is likely to be separated when it freezes in a state where it comes into contact.

  As mentioned above, although this invention was demonstrated according to the said embodiment, this invention is not limited only to the said aspect, The various aspect according to the principle of this invention is included.

It is sectional drawing of the diaphragm type solenoid valve in embodiment of this invention. It is the graph which measured the temperature of the main valve with respect to the elapsed time when it supplies with electricity to the diaphragm type solenoid valve of this invention.

Explanation of symbols

1: Diaphragm valve 1a: Main valve 1b: Convex part 2: Valve seat 2c: Seat part 3: Movable iron core 3a: Concave part (mounting surface)
4: Solenoid coil 8: Fixed iron core 10: First body 14: Second body 11: First port (fluid inlet)
12: Second port (fluid outlet)
100: Diaphragm type solenoid valve (solenoid valve)

Claims (4)

A valve seat provided between a first port and a second port through which fluid flows;
A diaphragm valve having a main valve, wherein the main valve is capable of blocking between the two ports by being separated from and contacting the valve seat;
A movable iron core that can move in the axial direction,
A diaphragm type solenoid valve provided with a solenoid coil disposed around the movable core and operating the movable core by excitation,
The diaphragm type solenoid valve, wherein the main valve is directly provided on the movable iron core, and heat generated by the solenoid coil is transmitted to the main valve when the movable iron core is operated. The diaphragm type solenoid valve according to claim 1, wherein a concave portion is formed on the valve seat side of the movable iron core, and a main valve is attached to the concave portion. The diaphragm type solenoid valve according to claim 1, wherein the main valve is larger than an outer shape of the valve seat. The diaphragm type solenoid valve according to claim 1 or 3, wherein an outer shape of the valve seat becomes smaller toward the diaphragm valve.

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