Proportional control valve with double shutoff function

Abstract

A proportional control valve with a double closing function is provided, which can suppress an increase in costs by enabling the closing valve and the proportional valve to be controlled by a single coil. A main valve core 30 and a proportional valve core 20 are connected by a first frame 5, and a main valve guide pipe 31 and one end of a proportional valve coil 21 are connected by a second frame 6 made of a magnetic material to form a magnetic passage that returns from the proportional valve core 20 to the proportional valve core 20 via the first frame 5, the main valve core 30, the main valve plunger 32, and the second frame 6. First, a voltage is applied to the proportional valve coil 21 in a direction in which the magnet 26 is attracted to the proportional valve core 20, and the closing valve 3 is opened with the proportional valve 2 closed. Next, the applied voltage is instantly reversed to apply a voltage to the proportional valve coil 21 in a direction in which the magnet 26 is repelled from the proportional valve core 20, and the proportional valve 2 is opened with the closing valve 3 open. The voltage applied to the proportional valve coil 21 is controlled to control the opening degree of the proportional valve 2.

Description

[Technical field]

[0001] The technology disclosed in this application relates to a proportional control valve with a double closing function that is disposed in a supply pipe that mainly supplies air, fuel gas, or the like, and controls the increase and decrease of the amount of supply to the supply pipe. [Background technology]

[0002] Conventionally, proportional valves that control the increase and decrease of the supply amount of air, fuel gas, or the like are disclosed in Patent Documents 1 and 2, for example.

[0003] Patent Document 1 discloses a control device for a governor proportional valve in which two solenoid valves from the upstream (primary side) and a governor proportional valve are integrated together.

[0004] Furthermore, Patent Document 2 discloses a proportional valve with a closing function in which a valve body is formed from metal or hard synthetic resin and a sealing member made of elastic synthetic rubber is attached to at least the portion of the valve body that comes into contact with the valve seat. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Special Publication No. 7-35864 [Patent Document 2] Japanese Utility Model Application Publication No. 63-106976 DISCLOSURE OF THEINVENTION [Problem to be solved by the invention]

[0006] Conventional gas governor proportional control valves are generally composed of a proportional valve with a rigid valve disc and valve seat that has no closing function, and two solenoid valves on the upstream side, as disclosed in Patent Document 1. On the other hand, Patent Document 2 also discloses a proportional valve that has a closing function added by attaching a seal member made of elastic synthetic rubber to the part of the proportional valve disc that contacts the valve seat. In this case, since the proportional valve also serves as the closing function, it is possible to reduce the number of solenoid valves to be disposed upstream.

[0007] The reason why a gas governor proportional control valve needs to have two shutoff functions is that safety standards stipulate that at least two shutoff valves (e.g., solenoid valves) (two solenoid valves in Patent Document 1, one solenoid valve and one proportional valve in Patent Document 2) must be arranged in series to prevent any danger even if a single solenoid valve fails for some reason and the solenoid valve's closing function is impaired.

[0008] In such governor proportional valve control devices consisting of one or two solenoid valves and a proportional valve, coils are used individually to drive the valve bodies. Since each coil uses copper wire, the recent rise in copper prices has led to increased costs.

[0009] The technology disclosed in this application has been proposed in consideration of the above-mentioned problems, and aims to provide a proportional control valve with a double closing function that enables the shut-off valve and proportional valve to be controlled by a single coil, thereby preventing costs from increasing. [Means for solving the problem]

[0010] In order to achieve the above object, the proportional control valve with double closing function according to claim 1 comprises a first valve body formed of an elastic member for opening or closing a primary-side valve port arranged on the primary side, a plunger made of a magnetic material connected to one end of the first valve body, a guide tube made of a non-magnetic material into which the plunger is slidably inserted from an open end of one end, a first fixed iron core arranged at the other end of the guide tube so as to face the plunger, and a biasing member for biasing the plunger in a direction away from the first fixed iron core, and a secondary-side valve port arranged on the secondary side. a proportional valve including a second valve body formed of an elastic member capable of opening or closing a port, a permanent magnet arranged to face the second valve body, a connecting member connecting the second valve body and the permanent magnet, a coil capable of driving the connecting member, a second fixed iron core arranged in the center of the coil substantially parallel to the first fixed iron core and facing the permanent magnet, a diaphragm connected to the connecting member and interlocking with the connecting member, and a back pressure chamber partitioned and formed by the diaphragm on a surface opposite to the surface on which the second valve body is provided; A proportional control valve with a double closing function is provided with a first plate made of a magnetic material arranged to connect a fixed iron core, and a second plate made of a magnetic material arranged to connect a guide tube and one end of a coil, and a magnetic passage is formed from the second fixed iron core through the first plate, the first fixed iron core, the plunger, and the second plate, and the first valve body of the closing valve and the second valve body of the proportional valve can be opened / closed by applying a voltage to a single coil of the proportional valve. First, a permanent magnet is placed against the second fixed iron core. a voltage is applied to the coil in a direction in which the permanent magnet is attracted to the second fixed iron core, such that the plunger of the shut-off valve is attracted toward the first fixed iron core against the biasing force of the biasing member to fully open the first valve body, thereby opening the shut-off valve with the proportional valve closed; next, a voltage whose polarity is instantly reversed in a direction in which the permanent magnet is repelled by the second fixed iron core but not so as to close the shut-off valve, thereby opening the proportional valve with the shut-off valve open, and the reversed applied voltage is controlled to make it possible to control the opening degree of the proportional valve. Effect of the Invention

[0011] In the proportional control valve with double closure function according to claim 1, a proportional valve according to a known technology in which a valve body (second valve body) is formed from an elastic material and also functions as a shutoff valve, and a shutoff valve arranged on the primary side are arranged in series, the fixed iron core (first fixed iron core) of the shutoff valve and the fixed iron core (second fixed iron core) of the proportional valve are connected by a plate (first plate) made of a magnetic material, and the guide tube of the shutoff valve and one end of the coil of the proportional valve are arranged so as to be connected by a plate (second plate) made of a magnetic material, thereby forming a magnetic passage that runs from the fixed iron core of the proportional valve through the first plate, the fixed iron core and plunger of the shutoff valve, and the second plate, and returns to the fixed iron core of the proportional valve, making it possible to control the opening / closing operation of the shutoff valve and the proportional valve by applying a voltage to a single coil provided in the proportional valve. This makes it possible to realize a proportional control valve with double closing function using a single coil, reducing the number of coils from the conventional two or three to one.

[0012] In addition, a moving magnet system using a permanent magnet is adopted for the proportional valve, and first a voltage is applied to the coil in the direction in which the permanent magnet is attracted to the second fixed iron core, thereby opening the stop valve with the proportional valve closed, and then a voltage with the polarity reversed in the direction in which the permanent magnet is repelled from the second fixed iron core is applied to the coil instantly, but not to the extent that the stop valve is closed, thereby opening the proportional valve with the stop valve open, and the reversed applied voltage is controlled to make it possible to control the opening degree of the proportional valve.

[0013] Even if the moving magnet method is not used, it is possible to realize a proportional control valve with double closing function using a single coil. However, in that case, after a current sufficient to open the closing valve has been applied, an even larger current will be applied to control the proportional valve, so a coil with great power will be required, which will result in the coil becoming huge. Even if the number of coils is reduced, the amount of copper wire used cannot be reduced, and as a result, there is a risk that costs cannot be reduced.

[0014] Therefore, in the present invention, a moving magnet system using a permanent magnet is adopted, and when controlling the proportional valve, the polarity of the voltage applied to the coil is reversed, making it possible to suppress the coil from becoming large. By adopting the moving magnet system in this way to control the polarity of the voltage applied to the coil and reducing the number of coils as described above, the amount of copper wire used for the coils can be reduced, and as a result, costs due to rising copper prices can be suppressed. [Brief description of the drawings]

[0015] [Figure 1] 1 is an external view of a proportional control valve with a double closing function according to one embodiment of the present invention. FIG. [Diagram 2] FIG. 1 is a cross-sectional view of a proportional control valve with double closing function. [Diagram 3] 13 is a cross-sectional view showing a state in which a voltage is applied to the coil in a direction in which the magnet is attracted. [Figure 4] 13 is a cross-sectional view showing a state in which a voltage is applied to a coil in a direction in which the magnets are repelled. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] First, a proportional control valve 1 with a double closing function, which is one embodiment of the present invention, will be described with reference to the drawings. Directional descriptions such as "up," "down," "right," and "left" used in the description are shown with respect to the drawings, and do not indicate actual positional relationships.

[0017] Fig. 1 is an external view of a proportional control valve 1 with a double closing function according to one embodiment of the present invention, which is installed in a gas supply path to a burner, etc. Fig. 1(A) is a front view, Fig. 1(B) is a left side view (as viewed from the front view), and Fig. 1(C) is a right side view (as viewed from the front view).

[0018] As shown in Fig. 1, proportional control valve 1 with double shutoff function has inlet 10 opening on the left side of body portion 4 and outlet 11 opening on the right side, with shutoff valve 3 and proportional valve 2 disposed in series from inlet 10. The upper end of shutoff valve 3 and the upper end of proportional valve 2 are connected by a first frame 5 made of a magnetic material, and the lower end of shutoff valve 3 and the lower end of proportional valve 2 are connected by a second frame 6 made of a magnetic material. Details of the connections will be described below.

[0019] Fig. 2 is a cross-sectional view of the proportional control valve with double closing function 1. Fig. 2(A) is a cross-sectional view taken along line AA of Fig. 1(B), and Fig. 2(B) is an enlarged view of part B surrounded by a two-dot chain line in Fig. 2(A).

[0020] The body 8 is provided inside the body portion 4, in which the proportional valve 2 and the stop valve 3 are assembled. The body 8 is provided with an inlet 10 consisting of cylindrical inlet openings 10a, 10b with different diameters provided continuously on the left side so that the diameter tapers toward the inside, an outlet 11 consisting of cylindrical outlet openings 11a, 11b with different diameters provided continuously on the right side so that the diameter tapers toward the inside, a main valve port 13 opened / closed by the stop valve 3, a proportional valve port 14 opened / closed by the proportional valve 2, and a valve chamber 15 above the proportional valve port 14. A plate-shaped second frame 6 made of a magnetic material such as metal is attached to the upper surface of the body 8 so as to cover the upper surface of the body 8. A plate 40 is attached to the lower surface of the body 8 via a cork packing 41. An O-ring 37 is interposed between the body 8 and the second frame 6, so as to maintain a sealed state between the second frame 6 and the body 8. Furthermore, a cork packing 41 maintains a sealed state between the body 8 and the plate 40.

[0021] The shutoff valve 3 is mainly composed of an iron main valve core 30, an iron main valve plunger 32, an aluminum main valve guide pipe 31, a main valve body 33, a main valve spring 34, and a main valve spring guide 35 from the top. The main valve core 30 is inserted into the main valve guide pipe 31 at the top end, and the main valve plunger 32 is slidably inserted from the bottom end. The main valve body 33 is made of an elastic member and is connected to the bottom end of the main valve plunger 32 in a direction opposite to the main valve core 30. The main valve spring 34 biases the main valve body 33 toward the main valve port 13 (valve closing direction), and is supported by a main valve spring guide 35 arranged above the main valve body 33. An O-ring 36 is interposed between the main valve core 30 and the main valve guide pipe 31, so that the main valve core 30 is kept sealed against the main valve guide pipe 31.

[0022] The proportional valve 2 is mainly composed of, from the top, an iron proportional valve core 20, a proportional valve coil 21, a holder 23, a magnet plate 24, a magnet 26, a stem 29, a diaphragm 25, a diaphragm holder 27, a spacer 28, a proportional valve body 22 and a backup spring 51.

[0023] A male thread (not shown) is machined on the side peripheral surface of the upper end of the proportional valve core 20, and a female thread that fits with the male thread of the proportional valve core 20 is machined in a first through hole 5a provided in the first frame 5, into which the upper end of the proportional valve core 20 is inserted, so that the vertical position of the proportional valve core 20 can be adjusted by rotating the proportional valve core 20. The proportional valve core 20 is fixed and held via the first frame 5 by a nut 50 that has a female thread that fits with the male thread of the proportional valve core 20. Then, as shown in FIG. 2, the proportional valve core 20 is inserted into a cylindrical through hole 21a provided in the center of the proportional valve coil 21 and assembled.

[0024] The holder 23 is made of aluminum, which is a non-magnetic material, and has a holder opening 23a at the bottom, which is cylindrical at the top and has a truncated cone shape with a diameter that widens downward, and a communication hole 23b that communicates with the atmosphere at the center of the upper surface. The space of the holder opening 23a functions as a back pressure chamber separated from the valve chamber 15 by a diaphragm 25 described below, and a magnet plate 24 with a cylindrical magnet 26 attached is disposed in the space of the holder opening 23a. A stem 29 is fixed to the magnet plate 24 by a push nut 52, with its upper part penetrating the lower end surface of the magnet plate 24. The proportional valve body 22 is attached to the lower end of the stem 29. The proportional valve body 22 is made of an elastic material such as rubber. In this embodiment, acrylonitrile butadiene rubber (NBR) is used as an example of an elastic material such as rubber. A diaphragm 25, which separates the valve chamber 15 in which the proportional valve element 22 is disposed and the opening 23a of the holder 23 in which the magnet plate 24 is disposed, is sandwiched and attached between the holder 23 and the diaphragm holder 27 between the magnet plate 24 and the stem 29. The diaphragm 25 is made of acrylonitrile butadiene rubber (NBR), which is an elastic member, and a thick cylindrical external seal portion 25a provided on the outer periphery maintains a sealed state between the holder 23 and the body 8.

[0025] The proportional valve element 22 is fixed to the diaphragm holder 27 by a spacer 28 provided in the middle of the stem 29. A backup spring 51 provided on the lower end surface of the stem 29 urges the proportional valve element 22 in the direction of the proportional valve port 14 (valve closing direction). As described below, when the proportional valve coil 21 is not energized, the magnet 26 is attracted toward the proportional valve core 20 by the magnetic force of the magnet 26. For this reason, the magnetic force of the magnet 26 serves as the urging force that urges the proportional valve element 22 in the direction of the proportional valve port 14 (valve closing direction), and therefore the backup spring 51 is not necessarily required.

[0026] A cylindrical protrusion 30a is formed at the upper end of the main valve core 30 of the shutoff valve 3, and the main valve core 30 is fixed to the first frame 5 by inserting and crimping the protrusion 30a into a second through hole 5b provided in the first frame 5. In this way, the proportional valve core 20 of the proportional valve 2 and the main valve core 30 of the shutoff valve 3 are connected by the first frame 5. In addition, the lower end of the main valve guide pipe 31 of the shutoff valve 3 and the lower end of the proportional valve coil 21 of the proportional valve 2 are connected by the second frame 6. In this way, by connecting the main valve core 30 of the shut-off valve 3 and the proportional valve core 20 of the proportional valve 2 with the first frame 5, and connecting the main valve guide pipe 31 of the shut-off valve 3 and the proportional valve coil 21 of the proportional valve 2 with the second frame 6, when a voltage is applied to the proportional valve coil 21 and the proportional valve coil 21 is excited, a magnetic passage can be formed that runs from the proportional valve core 20 of the proportional valve 2 through the first plate 5, the main valve core 30 and main valve plunger 32 of the shut-off valve 3, and the second plate 6, and returns to the proportional valve core 20 of the proportional valve 2.

[0027] The operational control of the proportional control valve 1 with double closing function configured as described above will be described with reference to FIGS.

[0028] When the proportional valve coil 21 is not energized, the main valve element 33 of the stop valve 3 is biased toward the main valve port 13 (valve closing direction) by the main valve spring 34 as shown in FIG. 2, so that the main valve element 33 seats on the main valve port 13 to close the main valve port 13. In the proportional valve 2, the magnet 26 is attracted toward the proportional valve core 20 by its magnetic force, so that the stem 29 and the proportional valve element 22 move upward as shown in FIG. 2, so that the proportional valve element 22 seats on the proportional valve port 14 to close the proportional valve port 14. As described above, the proportional valve element 22 is made of acrylonitrile-butadiene rubber (NBR), which is an elastic member, so that it can also function as a stop valve. As a result, the proportional control valve 1 with double closing function can be doubly closed by the main valve element 33 of the stop valve 3 and the proportional valve element 22 of the proportional valve 2.

[0029] Next, a method for controlling the proportional control valve 1 with double closing function by energizing the proportional valve coil 21 will be described. Fig. 3 is a cross-sectional view showing a state in which a voltage is applied to the proportional valve coil 21 in a direction in which the magnet 26 is attracted to the proportional valve core 20, and Fig. 4 is a cross-sectional view showing a state in which a voltage is applied to the proportional valve coil 21 in a direction in which the magnet 26 is repelled from the proportional valve core 20.

[0030] First, as shown in Fig. 3, a voltage is applied to the proportional valve coil 21 to excite the magnet 26 in a direction to attract the proportional valve core 20. Then, the magnetic passage is excited as shown by the arrow M1 in Fig. 3. In this case, as shown by the arrow (1) in Fig. 3, a voltage is applied to the proportional valve coil 21 such that the main valve plunger 32 of the closing valve 3 moves by attraction toward the main valve core 30 against the biasing force of the main valve spring 34, and the main valve body 33 moves away from the main valve port 13 to fully open the main valve port 13. As for the proportional valve 2, a force acts in a direction to attract the magnet 26 to the proportional valve coil 21 as shown by the arrow (2) in Fig. 3, so that the proportional valve body 22 remains seated on the proportional valve port 14, and the proportional valve port 14 is closed.

[0031] Next, as shown in FIG. 4, a voltage with reversed polarity for magnetizing the magnet 26 in a direction repelling the proportional valve core 20 is applied to the proportional valve coil 21. Then, the magnetic passage is excited as shown by the arrow M2 in FIG. 4. At this time, the voltage polarity is reversed instantaneously to the extent that the closing valve 3 can be kept fully open. Then, the main valve element 33 of the closing valve 3 moves away from the main valve port 13, and the main valve port 13 remains fully open, while the magnet 26 of the proportional valve 2 repels the proportional valve core 20, and the proportional valve element 22 moves in a direction away from the proportional valve port 14, as shown by the arrow (1) in FIG. 4, and the proportional valve port 14 opens. Then, by controlling the voltage applied to the proportional valve coil 21 in a state where the polarity of the voltage is reversed, the degree of opening of the proportional valve port 14 is controlled, and the amount of gas flowing through the proportional valve port 14 can be adjusted.

[0032] As described above, in the proportional control valve 1 with double closing function of this embodiment, the proportional valve coil 21 of the proportional valve 2, which is a single coil, can control the opening / closing operation of the stop valve 3 and the proportional valve 2. In addition, by adopting a moving magnet system using the magnet 26, which is a permanent magnet, and controlling the polarity of the voltage applied to the proportional valve coil 21 when controlling the proportional valve 2 as in the present invention, it is possible to control the stop valve 3 and the proportional valve 2 without enlarging the proportional valve coil 21, which is a single coil. This makes it possible to reduce the amount of copper wire used for the coil, and thus makes it possible to suppress cost increases even under conditions of rising copper prices.

[0033] Here, the proportional control valve 1 with double closure function is an example of a proportional control valve with double closure function, the main valve port 13 is an example of a primary side port, the main valve valve body 33 is an example of a first valve body, the main valve plunger 32 is an example of a plunger, the main valve guide pipe 31 is an example of a guide tube, the main valve core 30 is an example of a first fixed iron core, the main valve spring 34 is an example of a biasing member, the stop valve 3 is an example of a stop valve, the main valve port 13 is an example of a secondary side port, and the proportional The valve valve body 22 is an example of a second valve body, the magnet 26 is an example of a permanent magnet, the stem 29 is an example of a connecting member, the proportional valve coil 21 is an example of a coil, the proportional valve core 20 is an example of a second fixed iron core, the diaphragm 25 is an example of a diaphragm, the opening 23a of the holder 23 is an example of a back pressure chamber, the proportional valve 2 is an example of a proportional valve, the first frame 5 is an example of a first plate, and the second frame 6 is an example of a second plate.

[0034] Although the embodiments of the present invention have been described in detail above, these are merely examples, and the present invention should not be construed in any way as being limited by the specific descriptions in the embodiments. It should be understood that the present invention can be embodied in various forms that include various changes, modifications, improvements, etc. based on the knowledge of those skilled in the art, and that all such embodiments are included within the scope of the present invention as long as they do not deviate from the spirit of the present invention. [Explanation of symbols]

[0035] 1. Proportional control valve with double closing function 2. Proportional valve 3. Shut-off valve 4. Body section 5. First frame 6. Second frame 10...Inlet 11·Outlet 13. Main valve opening 14 Proportional valve port 15. Valve chamber 20 Proportional valve core 21 Proportional valve coil 22 Proportional valve body 23 Holder 25 Diaphragm 26. Magnet 29 Stem 30 ··Original valve core 31 Main valve guide pipe 32 Main valve plunger 33 Main valve body 34··Shutter valve spring

Claims

[Claim 1] a first valve body formed of an elastic member that opens or closes a primary side valve port disposed on the primary side; a plunger made of a magnetic material, the plunger having one end connected to the first valve body; a guide tube made of a non-magnetic material into which the plunger is slidably inserted from an open end of the guide tube; a first fixed core disposed at the other end of the guide tube so as to face the plunger; a stop valve including a biasing member that biases the plunger in a direction away from the first fixed iron core; a second valve body formed of an elastic member capable of opening or closing a secondary valve port disposed on the secondary side; a permanent magnet disposed to face the second valve body; a connecting member that connects the second valve body and the permanent magnet; A coil capable of driving the connecting member; a second stationary core disposed at the center of the coil, substantially parallel to the first stationary core, and facing the permanent magnet; a diaphragm connected to the connecting member and adapted to move with the connecting member; a proportional valve including a back pressure chamber defined by the diaphragm on a surface side opposite to a surface side on which the second valve body is provided; a first plate made of a magnetic material arranged to connect the first stationary iron core and the second stationary iron core; a second plate made of a magnetic material arranged to connect the guide tube and one end of the coil, a proportional control valve with a double closing function, in which a magnetic path is formed from the second fixed iron core through the first plate, the first fixed iron core, the plunger, and the second plate, and which enables opening / closing operations of the first valve body of the stop valve and the second valve body of the proportional valve by application of a voltage to a single coil of the proportional valve, First, a voltage is applied to the coil in a direction in which the permanent magnet is attracted to the second fixed iron core, the voltage being sufficient to attract the plunger of the stop valve toward the first fixed iron core against the biasing force of a biasing member and fully open the first valve body, thereby opening the stop valve with the proportional valve closed; Next, a voltage whose polarity is instantly reversed in a direction in which the permanent magnet repels the second fixed iron core is applied to the coil, but not to the extent that the shut-off valve is closed, thereby opening the proportional valve with the shut-off valve open, and the reversed applied voltage is controlled to control the opening degree of the proportional valve.

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