JPH07787Y2 - solenoid valve - Google Patents

Description

[Detailed description of the device] [Industrial applications]

The present invention relates to a solenoid valve that performs a valve action by pressing a plunger against a valve seat or separating it from a valve seat.

2. Description of the Related Art A conventional two-position or three-position so-called double solenoid type solenoid valve is provided with two solenoids, two plungers and two fixed iron cores. An object of the present invention is to provide a solenoid valve that can be made smaller than the conventional solenoid valve, can be reliably opened and closed, and consumes less power.

[Means for Solving the Problems]

The solenoid valve of the present invention is characterized by adopting the following configuration, which will be described with reference numerals of the embodiments. A pair of plungers 7 which are permanent magnets are fitted into plunger chambers 4 formed on both sides of the fixed iron core 2 in the axial direction so as to be slidable and the same magnetic poles face each other with the fixed iron core 2 interposed therebetween. I dressed up. A valve seat 12 that cooperates with each plunger 7 to open and close between the import 9 and the outport 18 is provided at the outer end of each plunger chamber 4. On the outer circumference of the fixed iron core 2, a single electromagnetic wave having a length longer than the fixed iron core 2 in the axial direction and extending beyond both ends thereof to the outer circumference of the plunger chamber 4 on both sides and having a larger magnetic force than that of the plunger 7 is generated. The solenoid 5 is provided. A polarity selector switch 24 for switching the energizing polarity is connected to the solenoid 5. Each piston chamber 11 continuous to the outer end of each plunger chamber 4
The hollow piston 20 is slidably arranged in the. A valve seat 16 which cooperates with the piston 20 to open and close between the out port 18 and the discharge port 10 is provided inside each piston 20. A spring 23 is urged on each plunger 7 so as to press the plunger 7 against the valve seat 12. A spring 22 is applied to each piston 20 by a spring force weaker than that of the spring 23 so as to urge the piston 20 into pressure contact with the corresponding plunger 7 and the valve seat 13.

[Action]

With such a structure, the fixed iron core 2 and the solenoid 5 can be shared by one pair with respect to the pair of plungers 7. When the solenoid 5 is off, the two plungers 7 are pressed against their respective valve seats 12 by the springs 23, while the two pistons 20 are pushed by the plungers 7 against the weak springs 22, as shown in FIG. Away from the valve seat 13. Since the pair of plungers 7 are permanent magnets, the polarity of the common solenoid 5 can be switched by the polarity changeover switch 24 to change the directions of the N and S magnetic poles of the common fixed iron core 2. One of the two plungers 7 is attracted to the fixed iron core 2 and the other is repulsed, and the pistons
20 is also switched, and each plunger 7 and piston 20 open and close the corresponding valve seat 12, 13 respectively. In this case, since the solenoid 5 extends from the outer periphery of the fixed iron core 2 beyond the left and right ends thereof to the outer periphery of the plunger chambers 11 on both sides, the longer the distance, the larger the magnetic flux capacity becomes and the magnet is magnetized. The magnetic force of the fixed iron core 2 can be increased. Moreover, since the solenoid 5 generates an electromagnetic force larger than the magnetic force of the plunger 7 which is a permanent magnet, the magnetic flux from the solenoid 5 is generated by the elongated portion.
Since it is possible to act on the fixed iron core 2 through the plunger 7, the magnetic flux utilization efficiency of the solenoid 5 is good and a magnetic circuit having a high magnetic flux density can be formed.

【Example】

Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In FIG. 1, a fixed iron core 2 is fixedly arranged in the center of a cylindrical casing 1, and a pair of left and right valve bodies 3 are fixed to both outer ends of the casing 1 so that the fixed iron core 2 can move in the axial direction. A pair of plunger chambers 4 is formed on both sides, that is, between the valve body 3 and the valve bodies 3 on the left and right sides. Casing 1
A solenoid 5 is wound around the outer periphery of the casing 1, and the casing 1 also serves as a winding cylinder. The solenoid 5 extends from the outer periphery of the fixed iron core 2 beyond the left and right ends thereof to the outer periphery of the plunger chambers 4 on both sides, and is covered with an outer cover 6. Plungers 7 are slidably fitted in the plunger chambers 4 on both sides. In these plungers 7, the same magnetic poles face each other with the fixed iron core 2 sandwiched between them. For example, the inside facing the fixed iron core 2 has an N pole,
The outside is a S-pole permanent magnet. A seal material 8 such as rubber is embedded in the recess of the outer end surface of each plunger 7. The solenoid 5 is longer in the axial direction than the fixed iron core 2 as described above, and generates an electromagnetic force larger than the magnetic force of the plunger 7, which is a permanent magnet. An import 9 and a discharge port 10 are provided on the outer surfaces of the valve bodies 3 on both sides, and a piston chamber 11 and
A first valve seat 12 located at the outer end of the plunger chamber 4 and a second valve seat 13 located in the opposite piston chamber 11 are provided. The valve opening 14 of the first valve seat 12 is a passage
Communicating with the import 9 via 15, the valve opening of the second valve seat 13
16 communicates with the exhaust port 10 via a passage 17. An outer end opening of each piston chamber 11 is covered with a cap 19 having an out port 18, and a hollow piston 20 is slidably fitted in the covered piston chamber 11. This piston
A sealing material 21 such as rubber is also embedded in the central portion of the outer end of 20. Then, each piston 20 has a second sealing material 21
The spring 22 is urged toward the second valve seat 13 side to close the valve opening 16 of the valve seat 13, so that the inner end of the piston 20 can engage with the outer end surface of the plunger 7. In addition, each plunger 7 has a seal member 8 for the first valve seat.
A spring 23 is urged toward the first valve seat 12 side to close the twelve valve openings 14. This spring 23 is a piston
Stronger than spring 22 above 20. The solenoid 5 is connected to an external DC power source 25 via a double type polarity changeover switch 24 which is interlocked. As shown in FIG. 1, when the polarity changeover switch 24 is set to the neutral position and the solenoid 5 is off, the plungers 7 on both sides press the seal member 8 against the first valve seat 12 by the springs 23. , The valve port 14 is closed. At this time, the pistons 20 on both sides are pushed against the springs 22 by the corresponding plungers 7 and separated from the second valve seat 13. Therefore, the valve port 16 of the second valve seat 13 is opened, and the out port 18 can communicate with the discharge port 10 through the opened valve port 13. FIG. 4 shows a fixed iron core 2 magnetized by the solenoid 5.
Of the plunger 7, which is a permanent magnet, and the repulsive force of the springs 22 and 23.
The vertical axis represents the force, and the horizontal axis represents the stroke of the plunger 7 based on the end surface of the fixed iron core 2. Further, in this figure, the positive force for attracting one plunger 7 to the fixed iron core 2 is shown above the horizontal axis, and the negative force against this, that is, the reaction force, is shown below the horizontal axis. In the figure, when the solenoid 5 is excited to attract one plunger 7 to the fixed iron core 2, one plunger 7
As for the attraction force due to the magnetic force of the
The magnetic resistance with the fixed iron core 2 decreases as it approaches the end surface of (1) (the stroke approaches 0), and thus rises in a curve. Further, the attraction force by the magnetic force of the fixed iron core 2 magnetized by the solenoid 5 also causes the magnetic flux from the solenoid 5 to flow through the plunger 7 to the fixed iron core 2,
As the plunger 7 approaches the end surface of the fixed iron core 2, it similarly curves and rises. Then, the combined suction force (+), which is a combination of these two suction forces, acts on the suction of one plunger 7 as a positive force. On the other hand, the other plunger 7 that repels the magnetized magnetic force of the fixed iron core 2 is biased to the valve seat 12 side and remains stopped, but since it is a permanent magnet, its magnetic force attracts one of the plungers 7. , It acts so as to reduce the magnetic flux of the fixed iron core 2, and acts as a constant reaction force on the one plunger 7 throughout the stroke. Further, the reaction force of the springs 22 or 23 linearly increases as the one plunger 7 approaches the end surface of the fixed iron core 2. Then, the combined reaction force (+
) Acts as a negative force on the suction of one plunger 7. Therefore, as shown by hatching in FIG. 4, the amount obtained by subtracting the combined reaction force (+) from the combined suction force (+) is the effective force for sucking the one plunger 7. When the polarity selector switch 24 is switched from the neutral position shown in FIG. 1 to the left side as shown in FIG. 2 to energize the solenoid 5 with the positive polarity, the fixed iron core 2 is excited with the right pole as the N pole and the left side as the S pole, and the right side is excited. In the plunger 7, since the repulsive force with the N pole of the fixed iron core 2 is further applied to the spring force of the spring 23,
It is pressed against the first valve seat 12 with a stronger force. On the other hand, the left plunger 7 is attracted to the fixed iron core 2 by the effective suction force as shown in FIG. 4, and is separated from the first valve seat 12 to open the valve port 14. Along with this, the piston 20 on the left side is moved to the right by the spring 22, and the sealing material 21 is moved to the second position.
The valve seat 16 is closed by pressing it against the valve seat 13. At this time, the left piston 20 and the left plunger 7 are separated. Therefore, the left import 9 communicates with the left outport 18 via the open valve port 14. Right import 9
The relationship between the out port 18 and the discharge port 10 is the same as in the case of FIG. When the polarity selector switch 24 is switched from the neutral position to the right side as shown in FIG. 3 and the solenoid 5 is energized with the negative pole, the fixed core 2 is excited with the left side as the N pole and the right side as the S pole. In addition, the left plunger 7 is pressed against the first valve seat 12 with a stronger force, and the right plunger 7 is attracted to the fixed iron core 2 by the effective suction force as shown in FIG. Away from and open its valve opening 14. Along with this, the piston 20 on the right side is moved leftward by the spring 22, and the seal member 21 is brought into pressure contact with the second valve seat 13 to close the valve port 16. At this time, the right piston 20 and the right plunger 7 are separated from each other, and the right import 9 communicates with the right out port 18 through the open valve port 14.

[Effect of device]

As described above, the solenoid valve of the present invention has the following effects. (1) Plungers and pistons are provided on both sides, and a three-port valve structure is used to open and close the valve seat, and two solenoids can be switched by one solenoid and one fixed iron core. Also, since the switching operation can be performed, two solenoid valves can be opened and closed by one solenoid. That is, since the same valve function as that of the conventional double solenoid type solenoid valve can be performed by one solenoid, the size can be reduced and the power consumption can be reduced as compared with the conventional double solenoid type solenoid valve. (2) By using a pair of plungers as permanent magnets and switching the polarity for energizing their common solenoids with the polarity switch, the direction of the N / S magnetic poles of the common fixed iron core changes, and both plungers are moved from the neutral state. One of the two is fixed to the fixed core and the other is repulsed, and the piston is also switched accordingly to open / close the two 3-port valves. It can be easily done by simply switching the energizing polarity of the solenoid.
Its control is easy. (3) The solenoid extends from the outer circumference of the fixed iron core to the outer circumferences of the plunger chambers on both sides beyond both left and right ends of the fixed iron core. The magnetic force can be increased. Moreover, since the solenoid generates an electromagnetic force that is larger than the magnetic force of the plunger, which is a permanent magnet, the magnetic flux from the solenoid can be made to act on the fixed iron core through the plunger due to its long portion. A magnetic circuit with high utilization efficiency and high magnetic flux density can be formed.

[Brief description of drawings]

FIGS. 1, 2 and 3 are sectional views of an embodiment of the present invention in different states. FIG. 1 shows a state in which the solenoid is off, and FIG. 2 shows a state in which the positive electrode is energized. , FIG. 3 is a graph for explaining a state when the negative electrode is energized, and FIG. 4 is a graph for explaining a force relationship for switching and operating the plunger. 2 ... Fixed core, 4 ... Plunger chamber, 5 ... Solenoid, 7 ... Plunger, 9 ... Import, 10 ... Discharge port, 11 ... Piston chamber, 12.13 ... Valve seat, 18 ... Out port, 20 …… piston, 22 ・ 23 …… spring,
24 ...... Polarity switch.

Claims (1)

[Scope of utility model registration request] 1. A plunger chamber 4 in which a pair of plungers 7 which are permanent magnets are formed on both sides of a fixed iron core 2 in the axial direction.
And the same magnetic poles are fitted so as to be opposed to each other with the fixed iron core 2 sandwiched therebetween. The import 9 and the outport in cooperation with each plunger 7.
A valve seat 12 that opens and closes between 18 and 18 is provided at the outer end of each plunger chamber 4, and the outer periphery of the fixed iron core 2 is longer than the fixed iron core 2 in the axial direction and beyond both ends of the plunger chamber 4. That one solenoid 5 having a length extending over the outer circumference of 4 and generating an electromagnetic force larger than the magnetic force of the plunger 7 is provided, and that this solenoid 5 is connected with a polarity changeover switch 24 for switching its conduction polarity, Each piston chamber 11 continuous to the outer end of each plunger chamber 4
In addition, a hollow piston 20 is slidably arranged, and a valve seat 16 that cooperates with the piston 20 to open and close between the out port 18 and the discharge port 10 is provided inside each piston 20. That is, each of the plungers 7 is provided with a spring 23 that urges the plunger 7 to press the valve seat 12, and each piston 20 has a spring force weaker than that of the spring 23. 7 and a spring 22 for urging the valve seat 13 so as to press it against the valve seat 13.