JP2984493B2 - solenoid valve - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solenoid valve used for industrial machinery, and more particularly, to a solenoid valve having a guide sleeve assembly in which a guide sleeve and a fixed iron core are fitted and fixed. About.

[0002]

2. Description of the Related Art Conventionally, solenoid valves that switch a port by driving a valve body by an electromagnet device have been used in industrial equipment in various fields. In the electromagnetic device of the solenoid valve,
Depending on how efficiently the magnetic flux generated by the coil is transmitted to the iron core, the attractive force between the fixed iron core and the movable iron core is affected,
The driving force for opening and closing the valve body is affected. If the magnetic flux transmission efficiency is poor, it is difficult to obtain a sufficient attraction force, so that it is necessary to increase the size of the coil to compensate for this, resulting in an increase in power consumption.

[0003] If there is a gap in the magnetic transmission path between the coil and the fixed iron core, the magnetic flux leaks from the gap and the magnetic efficiency deteriorates. Therefore, a non-magnetic tubular member called a guide sleeve is welded to a fixed iron core to form a guide sleeve assembly, which is inserted into a bobbin around which a coil is wound via an auxiliary core, and the inner surface of the bobbin and the auxiliary core is connected to the sleeve. The outer peripheral surface is brought into close contact with no gap. This aims to transmit the magnetic flux generated by the coil to the fixed iron core through the guide sleeve without leakage. The present applicant has disclosed a method of inserting such a guide sleeve assembly into an electromagnet apparatus via upper and lower auxiliary cores, as disclosed in Japanese Patent Application No. Hei 2-1.
No. 97047.

[0004]

However, even if the method of welding the guide sleeve to the fixed iron core is employed, it is not possible to completely eliminate the generation of a gap which causes a magnetic flux leakage. The reason is that, as shown in FIG.
Since the outer peripheral surface of the guide sleeve 31 and the outer peripheral surface of the guide sleeve 31 are flush with each other, the inner diameter of the bobbin and the auxiliary core is set to be smaller than the outer diameter of the guide sleeve 31 in order to clear the weld margin 36 generated by welding. Insertion cannot be done unless the protrusion is large.

Accordingly, as shown in FIG. 8A, the inner peripheral surface of the bobbin 32 and the lower auxiliary core 35 and the guide sleeve 31
The close contact with the outer peripheral surface is hindered, and a gap is generated. Also, a gap is generated between the fixed iron core 33 and the upper auxiliary core 34.
Magnetic flux leakage occurs in these gaps and the magnetic efficiency is reduced, so that the attractive force of the electromagnet cannot be sufficiently obtained. If the inner diameter of the upper auxiliary core 34 is made equal to the outer diameter of the fixed iron core 33, the upper auxiliary core 34 and the fixed iron core 33 are in close contact with each other as shown in FIG. However, the gap between the bobbin 32 and the lower auxiliary core 35 and the guide sleeve 31 cannot be eliminated with the disadvantage that the lower auxiliary core 35 and the upper auxiliary core 34 cannot be used as common parts. Needless to say, this problem can be avoided if the welding excess 36 is polished and removed after welding, but an increase in cost is unavoidable in order to perform correct polishing with the required accuracy.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and eliminates the generation of a gap which causes magnetic flux leakage without adding a polishing step after welding. It is an object of the present invention to provide an excellent electromagnetic valve which improves magnetic efficiency, secures an attractive force of an electromagnet, and realizes a common upper and lower auxiliary core.

[0007]

In order to solve the above-mentioned problems, a solenoid valve according to the present invention is a solenoid valve in which a valve for switching communication between ports is driven by an electromagnet device, and a coil of the electromagnet device is wound. A fixed core fitted and fixed to one end of a hollow hole of a hollow cylindrical bobbin via an auxiliary core, and a guide sleeve inserted to the other end of the hollow hole of the bobbin via an auxiliary core and joined to the fixed core. And a movable core that is slidably held in the guide sleeve and drives the valve element, and has a step formed in a sleeve portion of the guide sleeve.

According to another aspect of the present invention, there is provided an electromagnetic valve in which a valve for switching communication between ports is driven by an electromagnet device, wherein an auxiliary core is provided at one end of a hollow hole of a hollow cylindrical bobbin around which a coil of the electromagnet device is wound. A fixed core fitted and fixed via the core, a guide sleeve inserted into the other end of the hollow hole of the bobbin via an auxiliary core and joined to the fixed core, and slidably held in the guide sleeve. A movable iron core for driving the valve element; and a step formed in a sleeve portion of the guide sleeve and a step formed in a portion of the fixed iron core to which the guide sleeve is welded. Configuration.

[0009]

In the solenoid valve of the present invention having the above-described structure, when a coil is energized to generate a magnetic field, the fixed core magnetizes and attracts the movable core. At that time, since the bobbin and the guide sleeve, and the auxiliary core and the fixed core are securely contacted, the magnetic flux leakage is small, and therefore the magnetic efficiency is good,
The fixed core is strongly magnetized. As a result, the movable iron core is attracted to the fixed iron core, whereby the valve body attached to the movable iron core is separated from the valve seat, and the two ports communicate with each other. When the energization of the coil is cut off, the iron core loses magnetic force, the valve body comes into contact with the valve seat by the elastic expansion force of the valve body spring, and the communication between the two ports is interrupted.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A solenoid valve according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a solenoid valve according to an embodiment of the present invention. The solenoid valve of the present embodiment has an upper half solenoid 23 and a lower half valve 2.
4 and the main part of the present invention is:
It is in the structure of the solenoid part 23. Therefore, the solenoid unit 23 will be described first. At the center of the solenoid portion 23, there is a coil 9 formed by winding a conductive wire around the body of a hollow cylindrical coil bobbin 8 having flanges at both ends. Around the outer periphery of the coil 9, two magnetic frames 7, which are U-shaped members, are mounted. The upper auxiliary core 1 and the lower auxiliary core 2 are inserted into the cylinder of the coil bobbin 8 from above and below.

A sleeve guide 21 is inserted and fixed to the lower auxiliary core 2. The upper auxiliary core 1 has a fixed iron core 13
Are inserted and fixed almost to the center of the coil 9. The sleeve guide 21 and the fixed iron core 13 are welded to form a sleeve guide assembly. Sleeve guide 2
A movable iron core 11 is fitted and held inside the inside 1 so as to be slidable in the vertical direction. The outer surface of the solenoid portion 23 is molded and fixed by the resin 20 so that the whole is integrated.

Next, the solenoid unit 2 having the above configuration
3, the shape of the sleeve guide 21, which is a main part of the present invention, will be described. FIG. 3 shows partial cross-sectional views of the fixed iron core 13 and the sleeve guide 21 before and after welding. Sleeve guide 2 before welding shown in FIG.
In No. 1, a step 5 is provided in the sleeve portion. The outer peripheral surface of the portion 10 that contacts the inner surface of the upper auxiliary core 1 of the fixed iron core 13 and the outer peripheral surface of a portion of the sleeve guide 21 below the step 5 of the sleeve portion are flush with each other. Therefore, as shown in FIG. 3B showing the state after the welding, the weld overlay 6 does not project from the outer peripheral surfaces of the fixed iron core 13 and the sleeve guide 21 due to the effect of the step 5. Here, the protrusion amount of the welding extra 6 is usually about 0.1 to 0.3 mm, so that the level difference 5 of about 0.3 to 0.5 mm is sufficient.

Accordingly, in the fixed iron core 13 and the sleeve guide 21 of the present embodiment, the outer diameters of the fixed core 13 and the sleeve guide 21 are projected from the inner diameters of the coil bobbin 8, the upper auxiliary core 1, and the lower auxiliary core 2. Insertion is possible without reducing the size. Therefore, as shown in the partial cross-sectional view of FIG. 4, the coil bobbin 8, the lower auxiliary core 2, and the sleeve guide 21, and the fixed iron core 13 and the upper auxiliary core 1 are in close contact with each other without any gap. Therefore, the magnetic flux generated by the coil 9 can be effectively transmitted to the fixed iron core 13, so that a strong attraction force can be generated with a small amount of current. In addition, it is not necessary to polish after welding and to remove the welding surplus 6, and the upper auxiliary core 1 and the lower auxiliary core 2 can be a common part.

Next, the valve portion 24 which is a component of the solenoid valve will be described with reference to FIG. The valve portion 24 communicates the two ports 15 and 16 formed in the valve body with the valve chamber 17 for accommodating the lower end of the movable iron core 11, and both ports 15 and 16 in the valve chamber 17. A valve seat 18 is provided. A valve body 14 made of an elastic material such as rubber is embedded in a portion of the movable iron core 11 that comes into contact with the valve seat 18. The lower end of the movable core 11 has a flange on the outside, and there is a valve body spring 12 for abutting on the upper surface of the flange to urge the movable core 11 downward. The other end of the valve spring 12 is in contact with the lower surface of the flange of the sleeve guide 21.

Next, the operation of the solenoid valve having the above configuration will be described. FIG. 1 shows a state in which no current flows through the coil 9. The movable core 11 is urged downward by a valve body spring 12, and the valve body 14 is in contact with a valve seat 18. Thus, the two ports 15 and 16 are not in communication, and the solenoid valve is in the closed state. FIG. 2 shows a state in which a current is flowing through the coil 9. When a current flows through the coil 9, the magnetic flux generated by the coil 9 is transmitted to the fixed core 13, and the fixed core 13 magnetizes and attracts the movable core 11. Since the suction force is stronger than the elastic expansion force of the valve body spring 12, the movable core 11 moves to a position where it comes into contact with the fixed core 13. Thereby, the valve element 14 separates from the valve seat 18 and
The two ports 15, 16 communicate with each other via the valve chamber 17, and the solenoid valve is opened. When the current of the coil 9 is turned off, the fixed core 13 and the movable iron core 11 are made of a soft magnetic material having a small coercive force, and lose their magnetic force. Return.

When the coil 9 is excited, the fixed iron core 13
In order to efficiently and strongly magnetize the magnetic flux, it is necessary that the magnetic flux generated by the coil 9 be efficiently transmitted to the fixed iron core 13 without leakage. For this purpose, it is necessary to reduce magnetic flux leakage between the fixed iron core 13 and the auxiliary core 1 and between the coil bobbin 8 and the auxiliary core 2 and the movable iron core 11. According to the solenoid valve of the present embodiment, the gap between the fixed iron core 13 and the auxiliary core 1 and between the coil bobbin 8 and the auxiliary core 2 and the movable iron core 11 via the guide sleeve 21 causes a magnetic flux leakage. Less is. Therefore, the fixed core 13 can be strongly magnetized with a small amount of current having a good magnetic efficiency, and the fixed core 13 generates a strong attractive force. Therefore, it is possible to reliably and efficiently switch the fluid by opening and closing the port. it can.

Next, a second embodiment of the present invention will be described. This embodiment is a solenoid valve having the same overall configuration and operation as the previous embodiment shown in FIG.
3 is a modification of the shapes of the fixed iron core 13 and the sleeve guide 21. FIG. 5 shows sectional views of the fixed iron core 13 and the sleeve guide 21 in this embodiment before and after welding. Compared to the one in FIG.
Not only is a step 5 provided at the sleeve portion of the fixed iron core 13, but also a step 4 is provided at a portion of the fixed iron core 13 to be welded to the sleeve guide 21. Upper auxiliary core 1 of fixed iron core 13
The outer peripheral surface of the portion 10 that contacts the inner surface and the sleeve guide 2
The outer peripheral surface of the portion below the step 5 of the sleeve portion 1 is shown in FIG.
They are flush with each other.

Therefore, as shown in FIG. 5B showing the state after welding, the weld margin 6 is generated mainly in the upward direction in the figure due to the effect of the step 4, and the weld margin is generated by the effect of the step 5. The bank 6 does not protrude from the outer peripheral surfaces of the fixed core 13 and the sleeve guide 21. In this embodiment, since steps are provided in both the fixed iron core 13 and the sleeve guide 21, the steps 4 and 5 may be formed in a total of about 0.3 to 0.5 mm.

Thus, in the present embodiment, as in the previous embodiment, the outer diameter of the fixed iron core 13 and the sleeve guide 21 is made larger than the inner diameters of the coil bobbin 8, the upper auxiliary core 1 and the lower auxiliary core 2 by welding. 6 can be inserted without being reduced by the amount of protrusion. Therefore, as in the previous embodiment, the coil bobbin 8, the lower auxiliary core 2, and the sleeve guide 21 are in close contact with each other, and the fixed iron core 13 and the upper auxiliary core 1 are in close contact with each other without any gap (see FIG. 6). Can be effectively transmitted to the fixed iron core 13. In addition, it is not necessary to polish after welding to remove the weld overlay 6, and the upper auxiliary core 1 and the lower auxiliary core 2 can be used as common parts as in the previous embodiment. Therefore, as in the previous embodiment, there is no gap between the fixed iron core 13 and the auxiliary core 1 and between the coil bobbin 8 and the auxiliary core 2 and the movable iron core 11, which cause magnetic flux leakage. Therefore, the magnetic efficiency is good, and the fixed core 13 can be strongly magnetized with a small amount of current.
Since 3 generates a strong suction force, the switching of the fluid by opening and closing the port can be performed reliably and efficiently.

The above-described embodiment does not limit the present invention in any way, and various modifications and improvements can be made without departing from the scope of the present invention. For example,
In each of the embodiments, the present invention is embodied by a direct-acting energized open two-port solenoid valve, but a pilot-operated solenoid valve, energized closed solenoid valve, or multi-port solenoid valve And the like, and can be applied to devices other than valves as long as they use electromagnets.

[0021]

As is apparent from the above description, according to the solenoid valve of the present invention, by providing a step in the guide sleeve or by providing a step between the fixed iron core and the guide sleeve, the welding margin can be increased. Since it does not protrude from the outer peripheral surface of the fixed iron core and the guide sleeve, it can be inserted into the coil bobbin and the auxiliary core without gaps without polishing to remove the welding excess, so that there is little magnetic flux leakage and high magnetic efficiency. A strong suction force is generated by the electric current, and the valve can be reliably opened and closed, and it also contributes to the common use of parts.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a solenoid valve according to the present invention when the valve is closed.

FIG. 2 is a sectional view of the solenoid valve according to the present invention when it is opened.

FIG. 3 is a cross-sectional view showing the shapes of a fixed iron core and a guide sleeve of the solenoid valve according to the present invention.
(B) shows the state after welding.

FIG. 4 is a sectional view of a solenoid portion of the solenoid valve according to the present invention.

FIG. 5 is a sectional view showing the shapes of a fixed iron core and a guide sleeve of the solenoid valve according to the present invention.
(B) shows the state after welding.

FIG. 6 is a sectional view of a solenoid portion of the solenoid valve according to the present invention.

FIG. 7 is a sectional view showing the shapes of a fixed iron core and a guide sleeve of a solenoid valve according to the related art.

FIG. 8 is a cross-sectional view of a solenoid portion of a solenoid valve according to the related art.

[Explanation of symbols]

 1, 2 auxiliary core 4, 5 step 8 bobbin 9 coil 11 movable iron core 13 fixed iron core 14 valve element 15, 16 port 21 guide sleeve 23 solenoid

Claims (2)

(57) [Claims] An electromagnetic valve for driving a valve for switching communication of a port by a solenoid, wherein a first auxiliary core made of a magnetic material is provided at one end of a hollow hole of a hollow cylindrical bobbin around which a coil of the solenoid is wound. And a fixed core, which is a magnetic body fitted and fixed via the second core, which is inserted into the other end of the hollow hole of the bobbin via a second auxiliary core having the same shape as the first auxiliary core, and welded to the fixed core. An electromagnetic valve having a guide sleeve, which is a non-magnetic material, and a movable iron core, which is slidably held in the guide sleeve and drives the valve element, wherein the fixed iron core has the guide sleeve. the position to be fitted welding has a small-diameter stepped portion, said guide sleeve, to a position where the are is fitted on the outer periphery of the fixed iron core engagement is welded, has a small diameter portion of the small diameter, the solenoid valve assembly In time, the and the guide sleeve
Assembling the welded part with the fixed core without any finishing
Solenoid valve characterized in that it can be operated . 2. A solenoid valve according to claim 1, have a second step formed in a portion of welding the guide sleeve of the fixed iron core, the welding between the guide sleeve and the fixed iron core
However, the end surface of the guide sleeve and the side surface of the second step
Solenoid valve characterized by being performed in .