JP2019039461A - Flow regulating valve - Google Patents

Abstract

To provide a flow regulating valve capable of securing a shaft diameter without burdening a motor, and capable of making a flow passage cross sectional area large in a case where opening is made large.SOLUTION: A flow regulating valve comprises: a body 5 formed with a flow passage 4, wherein the flow passage is opened at an inflow port and an outflow port; an orifice 6 provided in the middle of the flow passage 4; and a shaft 3 with a valve body 2. The shaft 3 advances/retreats with respect to an orifice hole 6A, to increase/decrease a clearance from and to the orifice hole 6A. On the shaft 3, a hollow hole 3A is formed for opening a tip part of the valve body 2 side, and also a communication port 3B communicating the hollow hole 3A and the flow passage 4 is formed on a side wall. With advancing/retreating of the shaft 3, an opening area of the communication port 3B with respect to the flow passage 4 can be changed.SELECTED DRAWING: Figure 3

Description

  The present invention relates to flow control valves for various fluids.

  Conventionally, as disclosed in Patent Document 1 below, a boiler is known in which a double shutoff valve and a flow rate adjustment valve are provided in a gas supply path to a burner. The flow control valve is provided with an orifice in the middle of the flow path, and the shaft can advance and retreat in the axial direction of the orifice (in the direction orthogonal to the radial direction of the orifice hole). The outer peripheral surface of the shaft is tapered. The valve body formed in is provided. Therefore, the flow rate can be adjusted by increasing or decreasing the gap between the orifice hole and the valve body by advancing and retracting the valve body with respect to the orifice hole by the shaft.

  In this type of flow rate adjusting valve, the diameter of the orifice hole is preferably large in order to ensure a large maximum flow rate, but the diameter of the orifice hole is preferably small in order to reduce the flow rate. For example, when used to adjust the gas flow rate to the boiler, the diameter of the orifice hole needs to be large in order to secure the flow rate at high combustion, but to reduce the flow rate until low combustion, the diameter of the orifice hole Need to be small.

  In the flow rate adjusting valve having a structure in which the flow rate increases as the shaft enters the orifice hole, the shaft remains in the orifice hole even when the maximum flow rate is ensured. Therefore, in order to increase the flow path area (clearance area between the orifice hole and the valve-equipped shaft) when fully opened without changing the diameter of the orifice hole, it is conceivable to reduce the shaft diameter. In that case, the pressure receiving area of the gas supply pressure (the pressure receiving area S3 to the valve body projected on the surface orthogonal to the axial direction of the shaft 3 'as shown in FIG. 6) becomes large, and it is applied to the motor that advances and retracts the shaft. There is an inconvenience that the torque is increased, and step-out and wear of the sliding part are increased.

Japanese Patent Laying-Open No. 2015-218950 (paragraph 0024, FIG. 1)

  The problem to be solved by the present invention is to provide a flow rate adjusting valve that can secure a shaft diameter without burden on the motor and can have a large flow path cross-sectional area when the opening degree is increased.

  The present invention has been made to solve the above-mentioned problems, and the invention according to claim 1 is provided in the middle of the flow path and a body in which a flow path that opens to an inflow port and an outflow port is formed. And a shaft that moves forward and backward with respect to the orifice hole to increase / decrease the gap with the orifice hole, and the shaft has a hollow hole that opens the tip on the valve body side. In addition, a communication port between the hollow hole and the flow path is formed in the side wall, and the opening area of the communication port with respect to the flow path can be changed as the shaft advances and retreats. This is a flow control valve.

  According to the first aspect of the present invention, the flow rate can be adjusted not only through the clearance between the orifice hole and the valve body but also through the flow path in the shaft. Therefore, it is possible to increase the flow path cross-sectional area when the opening degree is increased while securing a shaft diameter without burden on the motor.

  The invention according to claim 2 is the flow rate adjusting valve according to claim 1, wherein the shaft is formed of a hollow pipe.

  According to invention of Claim 2, it can comprise simply by using a hollow pipe as a shaft.

  According to a third aspect of the present invention, as the shaft is pushed out from the maximum retracted position, first, the clearance between the orifice hole and the valve body is increased in a state where the communication port is closed, and then the communication port The flow regulating valve according to claim 1 or 2, wherein the opening area is increased by increasing the opening area.

  According to the third aspect of the present invention, in a relatively small flow rate region, the flow rate can be easily adjusted only by increasing / decreasing the gap between the orifice hole and the valve element without using the flow path in the shaft. . On the other hand, in a relatively large flow rate region, a large flow rate can be adjusted by using a flow path in the shaft.

  Furthermore, the invention according to claim 4 is characterized in that the shape of the communication port is set so that the flow rate of the communication port increases proportionally as the shaft is pushed out. 4. The flow rate adjustment valve according to any one of 3 above.

  According to the fourth aspect of the present invention, the flow rate of the communication port increases in proportion to the pushing out of the shaft, so that the flow rate adjusting valve is easy to use.

  ADVANTAGE OF THE INVENTION According to this invention, while being able to ensure the shaft diameter without the burden to a motor, the flow volume adjustment valve which can take the flow-path cross-sectional area when the opening degree is enlarged is realizable.

BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic which shows the flow regulating valve of one Example of this invention, and shows a part in cross section. It is the longitudinal cross-sectional view which expanded a part of flow regulating valve of FIG. 1, and has shown the state which closed the valve most. It is the longitudinal cross-sectional view which expanded a part of flow regulating valve of FIG. 1, and has shown the state which opened the valve to the middle. It is the longitudinal cross-sectional view which expanded a part of flow regulating valve of FIG. 1, and has shown the state which opened the valve most. 4A is a diagram showing a flow path cross-sectional area, and FIG. 5B is a diagram showing a pressure receiving area of a gas supply pressure applied to the valve body. It is a figure which shows the pressure-receiving area of the gas supply pressure concerning a flow-path cross-sectional area and a valve body about the conventional flow regulating valve.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic view showing a flow regulating valve 1 according to an embodiment of the present invention, and a part thereof is shown in cross section. FIG. 2 is an enlarged view of a part of FIG.

  Hereinafter, for convenience of description, directions may be referred to as up and down and left and right in the state of FIG. 1, but this is not intended to limit the posture of the flow rate adjusting valve 1 in use. Further, with respect to the shaft 3 for moving the valve body 2, the lower side in FIG. 1 may be referred to as the distal end side, and the upper side in FIG.

  The flow rate adjusting valve 1 of the present embodiment includes a body 5 in which a flow path 4 is formed, an orifice 6 provided in the flow path 4 in the body 5, and a shaft 3 for moving the valve body 2 forward and backward with respect to the orifice 6. And an actuating device 7 for moving the shaft 3 back and forth.

  The body 5 is a valve box that accommodates the orifice 6 and the valve body 2 in which the flow path 4 that opens to the inlet 4A and the outlet 4B is formed. In the illustrated example, the body 5 includes a hollow portion 4 </ b> C that opens upward, and the upper opening is closed by a lid 8 (the case lower wall of the operating device 7). In addition, the body 5 communicates with the hollow portion 4C extending in the vertical direction, and the body 5 is opened to the upper left wall to form the inlet 4A, while the body 5 is opened to the lower right wall to form the outlet 4B. ing. Thus, the flow path 4 is formed in the body 5 by the hollow part 4C provided with the inflow port 4A and the outflow port 4B. In addition, in the inflow port 4A and the outflow port 4B, flanges 5A and 5B are formed in the body 5, and the body 5 can be connected to various pipes and the like using the flanges 5A and 5B.

  In the flow path 4 in the body 5, an annular orifice mounting portion 4 </ b> D parallel to the horizontal plane is formed at the center in the vertical direction of the hollow portion 4 </ b> C. The outer peripheral portion of the orifice 6 is fixed to the orifice mounting portion 4D by being screwed from above. The inflow port 4A is formed above the orifice mounting portion 4D, and the outflow port 4B is formed below the orifice mounting portion 4D.

  The orifice 6 is formed of an annular plate material in which an orifice hole 6A is formed. In the illustrated example, the inner peripheral portion of the orifice 6 (that is, the orifice hole 6A) is formed in a substantially arc shape so as to increase in diameter as it goes upward.

  A shaft 3 having a valve body 2 can be advanced and retracted through the orifice hole 6A. In the present embodiment, the shaft 3 is formed of a hollow pipe (typically a round pipe) that opens to the tip surface, and the valve body 2 is fixed to the outer peripheral surface of the tip portion. The valve body 2 is formed in a tapered shape so that the outer peripheral surface is reduced in diameter as it goes to the proximal end side (upper side in FIG. 1) of the shaft 3. This taper surface is proportional to the shape of the orifice hole 6A, and, as will be described later, the flow rate through the gap with the orifice hole 6A increases proportionally as the shaft 3 is pushed out. It is preferable to form a shape in which the flow rate through the gap with the orifice hole 6A decreases proportionally with pulling back.

  In the shaft 3, the hollow hole 3 </ b> A opens to the distal end portion, but is closed at the proximal end portion. Moreover, although mentioned later for details, the communication port 3B of the hollow hole 3A and the flow path 4 is formed in the side wall of the shaft 3 (FIG. 3).

  The shaft 3 penetrates the lid 8 of the body 5 in an airtight manner, and is provided so as to be able to advance and retreat with respect to the orifice hole 6A. In the illustrated example, a guide cylinder 9 is integrally formed in the lid member 8 so as to protrude into the body 5, and the shaft 3 is passed through an inner hole of the guide cylinder 9 so as to be able to advance and retract. At that time, the gap between the inner peripheral surface of the guide tube 9 and the outer peripheral surface of the shaft 3 is sealed with a sealing material such as an O-ring 10 provided at the lower end of the guide tube 9. Moreover, since the motor (not shown) in the actuator 7 has a canned structure (that is, a canned motor), there is no possibility that the fluid passing through the flow path 4 leaks to the outside when the flow rate adjusting valve 1 is used.

  The actuating device 7 includes a motor, and the shaft 3 can be moved forward and backward with respect to the hollow portion 4C (in other words, the orifice hole 6A) in the body 5 by forward and reverse rotation of the motor. In this embodiment, the motor is a stepping motor and is controlled by a controller (not shown). The controller can check the origin at least in the closed position of the valve (FIG. 2) by the sensor.

  Next, the operation of the flow rate adjusting valve 1 of this embodiment will be described. In addition, the fluid passed through the flow rate adjusting valve 1 is not particularly limited, but is a gas here. For example, the flow rate adjusting valve 1 is used to adjust the gas flow rate to the burner and is provided downstream of the double shutoff valve. In this case, in the body 5 of the flow rate adjusting valve 1, the inlet 4A is connected to the gas supply source via each shut-off valve, and the outlet 4B is connected to the burner. In the following description, the fluid is assumed to be gas, but the same applies to other fluids.

  FIGS. 2 to 4 are views showing a usage state of the flow rate adjusting valve 1 of the present embodiment, FIG. 2 is a state where the valve is most closed (opening degree 0%), and FIG. FIG. 4 shows a state where the valve is most open (opening degree 100%). In these drawings, only the main part of the flow rate adjusting valve 1 of FIG. 1 is shown enlarged.

  FIG. 2 shows a state in which the valve body 2 is pulled back most to the actuator 7 side (maximum retracted position of the shaft 3), and the outer peripheral surface of the lower end portion of the valve body 2 contacts the inner peripheral surface of the lower end portion of the orifice hole 6A. Or close. At this time, the gap between the valve body 2 and the orifice hole 6A may be completely eliminated, and the flow path 4 may be fully closed (the flow rate is made zero). However, in this embodiment, even in this state, A slight gap is ensured between the orifice hole 6A and cannot be fully closed (a configuration in which gas leaks at a minimum flow rate). In this case, in order to completely shut off the gas supply to the burner, the shut-off valve provided in series with the flow rate adjusting valve 1 may be closed. In the state of FIG. 2, the communication port 3 </ b> B (FIG. 3) of the shaft 3 is disposed above the lower end portion (more specifically, the O-ring 10) of the guide tube 9, and the hollow hole 3 </ b> A in the shaft 3 is inserted. Does not flow gas.

  When the motor in the actuator 7 is rotated forward from the state of FIG. 2, the shaft 3 with the valve body 2 is pushed downward accordingly. As the shaft 3 is pushed out, first, the communication port 3B of the shaft 3 is still closed (that is, the communication port 3B is disposed in the guide tube 9), and the clearance between the orifice 6 and the valve body 2 is increased. Spread gradually and increase the flow rate. At this time, as the shaft 3 is pushed out, the valve body 2 and the orifice are arranged so that the flow rate through the gap between the orifice 6 and the valve body 2 increases proportionally (that is, the extrusion amount and the flow rate become proportional). The shape of the hole 6A is preferably set.

  When the shaft 3 is pushed out from the maximum retracted position of the shaft 3 in FIG. 2, the communication port 3B on the side wall of the shaft 3 is gradually exposed below the lower end portion of the guide tube 9 as shown in FIG. Open to the flow path 4. Thereby, the gas from the inlet 4A can flow to the outlet 4B even through the hollow hole 3A of the shaft 3. At this time, it is preferable that the shape of the communication port 3B is set so that the flow rate through the communication port 3B increases proportionally as the shaft 3 is pushed out. More preferably, as the shaft 3 is pushed out, the total flow rate from the inlet 4A to the outlet 4B (flow rate through the gap between the orifice hole 6A and the valve body 2 + flow rate through the hollow hole 3A of the shaft 3) and It is preferable that the shapes of the valve body 2, the orifice hole 6A, and the communication port 3B are set so that.

  FIG. 4 shows a state in which the valve body 2 is pushed out most (maximum extension position of the shaft 3). When the entire valve body 2 has passed through the orifice hole 6A, the portion corresponding to the orifice hole 6A includes the shaft 3. Will be passed. In this state, gas flows through the gap between the inner peripheral surface of the orifice hole 6A and the outer peripheral surface of the shaft 3. In this state, the entire communication port 3 </ b> B on the side wall of the shaft 3 is exposed and opened below the guide tube 9. Accordingly, the maximum flow rate through the hollow hole 3A of the shaft 3 is also ensured.

  On the other hand, in any of the above stages, the flow rate can be reduced by reversing the motor so that the shaft 3 with the valve body 2 is pulled back upward. For example, as the shaft 3 is pulled back from the fully open position in FIG. 4, the opening of the communication port 3B to the flow path 4 gradually decreases, and in parallel or thereafter, the gap between the orifice hole 6A and the valve body 2 Is gradually reduced, the gas flow rate passing through the flow rate adjusting valve 1 can be gradually reduced.

  According to the flow rate adjusting valve 1 of the present embodiment, the flow rate can be adjusted not only through the gap between the orifice hole 6A and the valve body 2, but also through the hollow hole 3A of the shaft 3. Even if the shaft 3 is not thinned to ensure a large flow rate, the flow passage cross-sectional area when the opening degree is increased can be increased while ensuring a shaft diameter without burden on the motor. This point will be specifically described as follows.

  FIG. 5 is a diagram showing the flow path cross-sectional area S1 when the flow rate adjusting valve 1 of the present embodiment is fully opened and the pressure receiving area S2 of the gas supply pressure applied to the valve body 2. Specifically, it shows a case of observing on a plane orthogonal to the axial direction of the shaft 3, (a) is a diagram showing the flow path cross-sectional area S1, (b) is a pressure receiving pressure of the gas supply pressure applied to the valve body 2 It is a figure which shows area S2. FIG. 6 is a view showing a flow passage cross-sectional area S3 and a pressure receiving area S3 of the gas supply pressure applied to the valve body 2 for a conventional flow rate regulating valve (a flow rate regulating valve in which the shaft 3 ′ is a solid shaft). is there.

When the flow regulating valve 1 is fully opened, the hatched portion S1 inside and outside the shaft 3 in FIG. For example, when the inner diameter (maximum inner diameter) of the orifice 6 is 18 mm, the outer diameter of the shaft 3 is 8 mm, and the inner diameter of the shaft 3 is 6 mm, the effective sectional area through which the gas flows is about 227 mm ² . Further, the pressure receiving area S2 of the gas supply pressure in this state is the area S2 of the shaded portion outside the shaft 3 in FIG. For example, in the case of the above example, the pressure receiving area S2 of the gas supply pressure is about 199 mm ² .

On the other hand, in the case of the conventional flow rate adjusting valve, as shown in FIG. 6, the cross-sectional area S3 of the hatched portion outside the solid shaft 3 'becomes an effective cross-sectional area through which gas flows when fully opened, which is the gas supply pressure. It is also the pressure receiving area. For example, when the inner diameter of the orifice 6 is 18 mm and the outer diameter of the shaft 3 ′ is 5 mm, these areas are about 229 mm ² .

  Comparing the respective areas S1 to S3 of the flow rate adjusting valve 1 of the present embodiment and the conventional flow rate adjusting valve, the pressure adjusting area S2 of the gas supply pressure is smaller in the flow rate adjusting valve 1 of the present embodiment than in the conventional case. However, the effective cross-sectional area S1 through which the gas flows can be ensured to be equal. In this way, according to the flow rate adjusting valve 1 of the present embodiment, the burden on the motor is reduced without reducing the diameter of the shaft 3 and thus without increasing the pressure receiving area S2 of the gas supply pressure applied to the valve body 2. And the flow rate can be increased.

  The flow rate adjusting valve 1 of the present invention is not limited to the configuration of the above embodiment, and can be changed as appropriate. In particular, (a) a body 5 in which a flow path 4 opening to the inlet 4A and the outlet 4B is formed, (b) an orifice 6 provided in the middle of the flow path 4, and (c) a valve body 2 are provided. And a shaft 3 that moves forward and backward with respect to the orifice hole 6A to increase / decrease the gap with the orifice hole 6A. (D) The shaft 3 is formed with a hollow hole 3A that opens the tip of the valve body 2 side. In addition, a communication port 3B between the hollow hole 3A and the flow channel 4 is formed in the side wall, and (e) the opening area of the communication port 3B with respect to the flow channel 4 can be changed as the shaft 3 advances and retreats. If so, other configurations can be changed as appropriate.

  For example, in the above-described embodiment, the shaft 3 is formed of a hollow pipe. However, the shaft 3 does not necessarily have to be formed in a pipe shape as long as the shaft 3 includes the hollow hole 3A that opens at the tip portion and the side wall.

  Moreover, in the said Example, the shape of the communicating port 3B provided in the shaft 3, the number, and a formation position can be changed suitably.

1 Flow control valve 2 Valve body 3 Shaft (3A: Hollow hole, 3B: Communication port)
4 Channels (4A: Inlet, 4B: Outlet, 4C: Hollow part, 4D: Orifice mounting part)
5 Body (5A: flange, 5B: flange)
6 Orifice (6A: Orifice hole)
7 Actuator 8 Lid 9 Guide cylinder 10 O-ring

Claims (4)

A body in which a flow path opening at the inlet and the outlet is formed;
An orifice provided in the middle of the flow path;
A valve body, and a shaft that moves forward and backward with respect to the orifice hole to increase or decrease the gap with the orifice hole;
In the shaft, a hollow hole that opens the tip on the valve body side is formed, and a communication port between the hollow hole and the flow path is formed in the side wall,
A flow rate adjusting valve characterized in that the opening area of the communication port with respect to the flow path can be changed as the shaft advances and retreats. The flow regulating valve according to claim 1, wherein the shaft is formed of a hollow pipe. As the shaft is pushed out from the maximum retracted position, the gap between the orifice hole and the valve body is first increased with the communication port closed, and then the communication port is opened to increase the opening area. The flow rate regulating valve according to claim 1 or 2, wherein: The flow rate adjustment according to any one of claims 1 to 3, wherein the shape of the communication port is set so that the flow rate of the communication port increases proportionally as the shaft is pushed out. valve.

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