JP7368826B2 - valve device - Google Patents

Description

The present application relates to a valve device.

As a valve device, a drain trap is known which is installed in a steam system and suppresses the discharge of steam while discharging condensate. When a steam system starts operating, it is necessary to quickly remove a large amount of remaining condensate using a drain trap in order to prevent water hammer that may occur due to steam mixing with low-temperature condensate remaining in the system. be.

For example, in the drain trap disclosed in Patent Document 1, a storage chamber is provided with two discharge holes of different sizes and two floats that open and close each discharge hole. In this drain trap, at the start of operation, drain is discharged from the lower discharge hole, which has a larger hole diameter. When the pressure rises to normal operating conditions, the lower discharge hole is closed by the float. Even if drain accumulates in the lower discharge hole, the float remains closed without floating up. This is because the size of the lower discharge hole is set so that the valve-closing force of the float generated by the pressure difference between the upstream and downstream sides of the discharge hole is greater than the valve-opening force of the float generated by buoyancy. be. On the other hand, the upper discharge hole is opened and closed by the float floating up and down depending on the drain storage position.

Japanese Patent Application Publication No. 2007-218332

In the above-described valve device, even when the operation is finished and the pressure decreases, there is a risk that the float will stick to the lower discharge hole and the discharge hole will remain closed. In this case, there is a possibility that the drain cannot be discharged from the lower discharge hole at the start of the next operation.

The technology disclosed in the present application was developed in view of such circumstances, and its purpose is to provide a valve device that can reliably open the valve at the start of operation and close it during subsequent operation.

The technology disclosed in this application is a valve device including a casing, a first valve mechanism, and a second valve mechanism. The casing is provided with a liquid inlet and a liquid storage chamber communicating with the inlet. The first valve mechanism includes a first liquid discharge hole provided in the storage chamber, and a float that is accommodated in the storage chamber and opens and closes the first discharge hole. The second valve mechanism is provided in the storage chamber, and includes a second discharge hole for liquid having a hole diameter larger than that of the first discharge hole; It has a valve body that opens and closes the two discharge holes. The second valve mechanism is provided on a side of the valve body opposite to the second discharge hole, and includes a spring that biases the valve body in a valve opening direction, and the second valve mechanism has a spring that biases the valve body in a valve opening direction. When the pressure increases to a certain value, the valve body is configured to move forward against the biasing force of the spring to close the second discharge hole.

According to the technology disclosed in this application, the valve can be reliably opened at the start of operation and closed during subsequent operation.

FIG. 1 is a sectional view showing a schematic configuration of a drain trap according to an embodiment. FIG. 2 is an enlarged view of the second valve mechanism according to the embodiment, and is a sectional view taken along line AA in FIG. FIG. 3 is a sectional view showing main parts of the second valve mechanism according to the embodiment. FIG. 4 is a diagram corresponding to FIG. 2 showing the second valve mechanism according to the embodiment.

Embodiments of the present application will be described below with reference to the drawings. Note that the following embodiments are essentially preferable examples, and are not intended to limit the technology disclosed in this application, its applications, or the scope of its uses.

The drain trap 1 of this embodiment is installed in a steam system or the like, and allows drain to flow out when drain flows in, while preventing drain from flowing out when steam flows in. The drain trap 1 is an example of a valve device, and the drain is an example of a liquid.

As shown in FIG. 1, the drain trap 1 includes a casing 10 in which a flow path for a fluid containing liquid is formed, and three valve mechanisms 30, 40, and 50 provided in the flow path to open and close the flow path. We are prepared. Drain that has flowed into the casing 10 flows out from the casing 10 via the first valve mechanism 30 and the second valve mechanism 40. The third valve mechanism 50 basically discharges the air that has entered the casing 10. However, the third valve mechanism 50 may discharge drain that has flowed into the casing 10.

The casing 10 has a middle part 11 and an upper part 12 and a lower part 13 attached above and below the middle part 11. The casing 10 is provided with a drain inlet 21 and an outlet 24, a drain storage chamber, and two discharge passages 25 and 26. The storage chamber includes a first storage chamber 22 that communicates with the inflow port 21 and a second storage chamber 23 that is provided below the first storage chamber 22 and communicates with the first storage chamber 22 . The first discharge passage 25 allows the first storage chamber 22 and the outlet 24 to communicate with each other, and the second discharge passage 26 allows the first storage chamber 22 and the first discharge passage 25 to communicate with each other.

In the casing 10, a flow path is formed by an inlet 21, two storage chambers 22, 23, an outlet 24, and two discharge passages 25, 26. Specifically, the flow path includes a first flow path and a second flow path for discharging condensate, and a third flow path for discharging air and condensate. The first flow path is formed by the inlet 21, the first storage chamber 22, the first discharge passage 25, and the outlet 24. The second flow path is formed by the inlet 21, the first storage chamber 22, and the second storage chamber 23. The third flow path is formed by the inlet 21, the first storage chamber 22, the second discharge passage 26, the first discharge passage 25, and the outlet 24.

The first storage chamber 22 is formed across the middle part 11 and the upper part 12, and the second storage chamber 23 is formed in the lower part 13. The first storage chamber 22 and the second storage chamber 23 are vertically divided by a partition wall 11a that is a part of the middle portion 11, and communicate with each other through a communication hole 14 provided in the partition wall 11a. The second storage chamber 23 has a smaller storage volume than the first storage chamber 22 . Unlike the first storage chamber 22, the second storage chamber 23 does not communicate with the first discharge passage 25 and the outlet 24, but communicates with the outside of the casing 10 (atmosphere) via the second valve mechanism 40. are doing.

The inlet 21 and the outlet 24 are provided in the middle portion 11 , and the inlet 21 communicates with the upper part of the first storage chamber 22 . The inlet 21 and the outlet 24 are formed on the same horizontally extending axis. The first discharge passage 25 is formed in the middle portion 11 , and has an upstream end connected to the lower part of the first storage chamber 22 and a downstream end connected to the outlet 24 . The second discharge passage 26 is formed across the middle part 11 and the upper part 12, and has an upstream end connected to the upper part of the first storage chamber 22, and a downstream end connected to the first discharge passage 25. Note that the inlet 21 and the outlet 24 are connected to piping of the steam system.

The first valve mechanism 30 opens and closes the first flow path. Specifically, the first valve mechanism 30 is a valve mechanism that allows drain to flow out from the first storage chamber 22 to the first discharge passage 25 while preventing steam from flowing out from the first storage chamber 22 to the first discharge passage 25. It is. The first valve mechanism 30 is provided in the first storage chamber 22 and includes a first valve body 31 and a first valve seat 32.

The first valve body 31 is a hollow spherical float, and is accommodated in the first storage chamber 22 in a free state. The first valve seat 32 is provided at a connection portion of the first storage chamber 22 with the first discharge passage 25 . A first drain hole 33 serving as a valve hole is formed in the first valve seat 32 . That is, the first discharge hole 33 is provided in the first storage chamber 22 and allows the first storage chamber 22 and the first discharge passage 25 to communicate with each other. The upstream end of the first discharge hole 33 constitutes an orifice.

In the first valve mechanism 30, the first valve body 31 rises and falls according to the drain storage level (drain water level) in the first storage chamber 22 to open and close the first discharge hole 33. Specifically, when the drain in the first storage chamber 22 increases, the first valve body 31 floats up and leaves the first valve seat 32, and the first discharge hole 33 is opened. On the other hand, when the drain in the first storage chamber 22 decreases, the first valve body 31 descends and seats on the first valve seat 32, and the first discharge hole 33 is closed. In this way, by opening and closing the first discharge hole 33, the first flow path is opened and closed.

More specifically, when the steam system is in operation, the pressure on the upstream side of the first discharge hole 33 increases to a predetermined value (hereinafter also referred to as operating pressure Pa). That is, a pressure difference (difference between the pressure in the first storage chamber 22 on the upstream side and the pressure in the first discharge passage 25 on the downstream side) occurs upstream and downstream of the first discharge hole 33. On the other hand, at the start of operation (at the start of operation), the pressure on the upstream side of the first discharge hole 33 does not rise immediately, so the pressure on the upstream side of the first discharge hole 33 is a pressure lower than the pressure Pa during operation. Pb (hereinafter referred to as pressure Pb at the start of operation). That is, the pressure difference in the first discharge hole 33 at the start of operation is smaller than during operation.

Here, the pressure on the upstream side of the first discharge hole 33 (or the second discharge hole 43 described later) can also be said to be the pressure of the inlet 21, the first storage chamber 22, and the second storage chamber 23, and This can also be said to be the pressure of the drain in the second storage chamber 23.

A force in the valve-closing direction (that is, a downward force, hereinafter also referred to as valve-closing force) acts on the first valve body 31 due to the pressure Pa during operation and the pressure Pb at the start of operation. In other words, when a pressure difference occurs in the first discharge hole 33, a valve closing force acts on the first valve body 31. In the first valve mechanism 30, the floating force of the first valve body 31 when the drain water level of the first storage chamber 22 is at a predetermined position is larger than the valve-closing force of the first valve body 31 due to the pressure Pa during operation. It is set. Therefore, in the first valve mechanism 30, when the drain water level in the first storage chamber 22 reaches a predetermined level, regardless of whether it is during operation or at the start of operation, the first valve body 31 floats and the valve is opened. Ru.

Note that, as a matter of course, the first valve body 31 has a larger valve-closing force due to the pressure Pa during operation than the valve-closing force due to the pressure Pb at the start of operation. Further, the buoyancy force of the first valve body 31 described above is the buoyancy force acting on the first valve body 31 minus its own weight.

Furthermore, a screen 27 is provided in the first storage chamber 22 at a portion communicating with the inflow port 21 . The screen 27 prevents foreign matter from flowing into the first storage chamber 22 from the inlet 21 . Further, the first storage chamber 22 is provided with a valve cover 28 near the top. The valve cover 28 is provided above the first valve seat 32 and partitions the first storage chamber 22 into upper and lower parts. The valve cover 28 prevents the first valve body 31 from floating above a predetermined height when the first valve body 31 floats up and contacts the valve cover 28 . Although not shown, the valve cover 28 is provided with a through hole through which drain from the inlet 21 flows.

The third valve mechanism 50 opens and closes the third flow path. Specifically, the third valve mechanism 50 allows low-temperature air and drain to flow out from the first storage chamber 22 to the second discharge passage 26, while preventing steam from flowing out from the first storage chamber 22 to the second discharge passage 26. It is a valve mechanism that prevents this. The third valve mechanism 50 is provided above the first storage chamber 22 and includes a third valve body 51 and a third valve seat 52.

The third valve body 51 is a temperature-responsive member, and although not shown, a thin plate diaphragm and a thermal expansion/contraction liquid are accommodated therein. The third valve seat 52 is provided at the connection part of the second discharge passage 26 in the first storage chamber 22 . A third discharge hole 53, which is a valve hole, is formed in the third valve seat 52. That is, the third discharge hole 53 is provided in the first storage chamber 22 and allows the first storage chamber 22 and the second discharge passage 26 to communicate with each other. The upstream end of the third discharge hole 53 constitutes an orifice.

In the third valve mechanism 50, the third valve body 51 expands or contracts depending on the temperature to open and close the third discharge hole 53. Specifically, when the temperature of the third valve body 51 (second storage chamber 23) becomes low, the third valve body 51 contracts and leaves the third valve seat 52, and the third discharge hole 53 is opened. . On the other hand, when the temperature of the third valve body 51 increases, the third valve body 51 expands and seats on the third valve seat 52, and the third discharge hole 53 is closed. In this way, by opening and closing the third discharge hole 53, the third flow path is opened and closed.

The second valve mechanism 40 opens and closes the second flow path. Specifically, the second valve mechanism 40 is a valve that allows drain to flow out directly from the second storage chamber 23 to the outside of the casing 10 (atmosphere), while preventing steam from flowing out from the second storage chamber 23 to the outside of the casing 10. It is a mechanism. The second valve mechanism 40 is provided in the second storage chamber 23 and includes a second valve body 41, a second valve seat 42, a spring 44, and a support member 45.

As shown in FIGS. 2 to 4, the second valve body 41 corresponds to the valve body according to the claims of the present application, and is formed in a disk shape. The second valve body 41 is housed in the second storage chamber 23 with its axis extending in the vertical direction. The second valve body 41 is provided to be movable up and down. The second valve body 41 is disposed above a second discharge hole 43, which will be described later, and opens and closes the second discharge hole 43 by moving up and down (that is, moving forward and backward toward the second discharge hole 43).

The lower part 13 is formed into a substantially cylindrical shape extending in the vertical direction, and has a second storage chamber 23 inside. A guide portion 13a is provided on the inner circumferential surface of the lower portion 13, protruding radially inward from the inner circumferential surface and extending in the vertical direction. A plurality of guide parts 13a (in this embodiment, three) are provided in the circumferential direction of the lower part 13 (see FIG. 3). The second valve body 41 is provided inside the plurality of guide parts 13a, and moves up and down along the guide parts 13a.

The second valve seat 42 is provided at the bottom of the second storage chamber 23. A second drain hole 43 serving as a valve hole is formed in the second valve seat 42 . That is, the second discharge hole 43 is provided at the bottom of the second storage chamber 23 and opens in the vertical direction. The second discharge hole 43 communicates the second storage chamber 23 with the outside of the casing 10 (the atmosphere). The upstream end of the second discharge hole 43 constitutes an orifice.

Further, the second discharge hole 43 has a larger hole diameter than the first discharge hole 33. Here, the hole diameter means the hole diameter at the upstream end of each discharge hole 33, 43 (that is, the diameter of the orifice).

The spring 44 urges the second valve body 41 in the valve opening direction, and is formed of a coil spring. The spring 44 is provided above the second valve body 41 in the second storage chamber 23 and urges the second valve body 41 upward. The spring 44 has one end connected to the upper surface of the second valve body 41 and supports the second valve body 41 . More specifically, one end of the spring 44 is fitted into and connected to an annular recess 41a formed on the upper surface of the second valve body 41.

The support member 45 supports the spring 44. The support member 45 is provided above the spring 44 in the second storage chamber 23, and is connected to the other end of the spring 44.

More specifically, the support member 45 is formed in a substantially disk shape, and is provided with its axis extending in the vertical direction. The support member 45 is provided coaxially with the second valve body 41 and has substantially the same diameter as the second valve body 41 . The other end of the spring 44 is fitted into and connected to an annular recess 45a formed on the lower surface of the support member 45.

Further, the support member 45 also serves as a baffle plate that prevents the drain flowing down from the first storage chamber 22 to the second storage chamber 23 through the communication hole 14 from hitting the upper surface of the second valve body 41 . That is, the support member 45 is provided so as to cover the upper surface of the second valve body 41.

Further, the support member 45 is provided so that its vertical position can be changed. Specifically, the support member 45 is fixed to the partition wall 11a with screws 46. By changing the screwing length of the screw 46 into the partition wall 11a, the vertical position of the support member 45 is changed.

The second valve mechanism 40 is configured such that the second valve body 41 moves forward and backward (up and down) to open and close the second discharge hole 43 according to the pressure in the second storage chamber 23 .

Specifically, in the second valve mechanism 40, when the pressure in the second storage chamber 23 decreases to a predetermined value (pressure Pb at the start of operation), the second valve body 41 is retracted (raised) by the urging force of the spring 44. and leaves the second valve seat 42. As a result, the second discharge hole 43 is opened. Further, in the second valve mechanism 40, when the pressure in the second storage chamber 23 rises to a predetermined value (pressure Pa during operation), the second valve body 41 moves forward against the biasing force of the spring 44. (descends) and seats on the second valve seat 42. As a result, the second discharge hole 43 is closed. In this way, the second flow path is opened and closed by opening and closing the second discharge hole 43.

More specifically, when the steam system is in operation, the pressure on the upstream side of the second exhaust hole 43, like the first exhaust hole 33, also rises to the operating pressure Pa. That is, a pressure difference (a difference between the pressure in the second storage chamber 23 on the upstream side and the atmospheric pressure outside the casing 10 on the downstream side) occurs upstream and downstream of the second discharge hole 43. On the other hand, at the start of operation (at the start of operation), similarly to the first discharge hole 33, the pressure on the upstream side of the second discharge hole 43 becomes the pressure Pb at the start of operation, which is lower than the pressure Pa during operation. That is, the pressure difference in the second discharge hole 43 at the start of operation is smaller than during operation.

Similar to the first valve body 31, a valve closing force (that is, a downward force) acts on the second valve body 41 due to the pressure Pa during operation and the pressure Pb at the start of operation. In other words, due to the pressure difference generated in the second discharge hole 43, a valve closing force acts on the second valve body 41. Note that, as a matter of course, the second valve body 41 has a larger valve-closing force due to the pressure Pa during operation than the valve-closing force due to the pressure Pb at the start of operation.

The biasing force of the spring 44 is set to be larger than the valve closing force of the second valve body 41 due to the pressure Pb at the start of operation. Further, the urging force of the spring 44 is set smaller than the valve closing force of the second valve body 41 due to the pressure Pa during operation. Therefore, at the start of operation, the second valve mechanism 40 opens as the pressure in the second storage chamber 23 decreases to the pressure Pb at the start of operation, and during subsequent operation, the pressure in the second storage chamber 23 decreases to the pressure at the time of operation. The valve closes as the pressure increases to Pa.

<Operation at start of operation>
The operation of the above-mentioned drain trap 1 at the time of starting operation of the steam system (starting up operation) will be explained. At the start of operation, the pressure and temperature on the upstream side of the first exhaust hole 33 and the second exhaust hole 43 are low, and low-temperature, low-pressure drain remains in the piping of the steam system. In other words, the pressures in the first storage chamber 22 and the second storage chamber 23 have decreased to the pressure Pb at the start of operation.

In the first valve mechanism 30, when there is no drain in the first storage chamber 22 or when the drain water level is lower than a predetermined level, the first valve body 31 is seated on the first valve seat 32, and the first discharge hole 33 is closed. Closed (see Figure 1). In the second valve mechanism 40, the biasing force of the spring 44 is greater than the valve-closing force of the second valve body 41 due to the pressure Pb at the start of operation, so the second valve body 41 is separated from the second valve seat 42. , the second discharge hole 43 is open (see FIG. 2). In the third valve mechanism 50, since the temperature of the first storage chamber 22 is low, the third valve body 51 is separated from the third valve seat 52, and the third discharge hole 53 is opened (see FIG. 1). That is, the first valve mechanism 30 is closed, and the second valve mechanism 40 and the third valve mechanism 50 are open.

Thus, at the start of operation, the second valve mechanism 40 and the third valve mechanism 50 are open, and residual condensate from the steam system flows into the drain trap 1. In the drain trap 1, drain that flows in from the inlet 21 flows from the first storage chamber 22 to the second storage chamber 23 through the communication hole 14, and flows out of the casing 10 from the second discharge hole 43 (is discharged). Since the second discharge hole 43 has a larger hole diameter than the first discharge hole 33, a large amount of drain is quickly discharged.

Note that air present in the piping of the steam system also flows into the drain trap 1 together with the residual drain. The air that has flowed into the drain trap 1 flows out from the first storage chamber 22 through the third valve mechanism 50 to the second discharge passage 26, passes through the first discharge passage 25, and then flows out from the outlet 24.

In this way, the drain trap 1 quickly discharges the low temperature drain and air remaining in the steam system at the start of operation.

Further, when the drain flows down from the first storage chamber 22 to the second storage chamber 23, the support member 45 can prevent the drain from hitting the upper surface of the second valve body 41. Therefore, shaking of the second valve body 41 that may occur when the drain hits the upper surface of the second valve body 41 is prevented.

<Operation during operation>
The operation of the above-mentioned drain trap 1 during operation of the steam system will be explained. During operation, the pressure and temperature on the upstream side of the first discharge hole 33 and the second discharge hole 43 are high, and high temperature and high pressure drain flows into the drain trap 1. That is, the pressures in the first storage chamber 22 and the second storage chamber 23 rise to the operating pressure Pa.

In the second valve mechanism 40, the biasing force of the spring 44 is smaller than the valve-closing force of the second valve element 41 due to the pressure Pa during operation, so the pressure Pa during operation causes the second valve element 41 to move toward the second valve seat. 42, and the second discharge hole 43 is closed (see FIG. 4). In other words, the second valve mechanism 40 is closed. Therefore, the drain that has flowed into the drain trap 1 flows from the first storage chamber 22 to the second storage chamber 23 and is stored therein.

When the second storage chamber 23 becomes full of drain, the first storage chamber 22 begins to collect drain. In the first valve mechanism 30, when the drain water level in the first storage chamber 22 rises to a predetermined level, the first valve body 31 floats up and leaves the first valve seat 32, and the first discharge hole 33 is opened. . In other words, the first valve mechanism 30 opens. Then, the drain in the first storage chamber 22 flows into the first discharge passage 25 via the first valve mechanism 30 and flows out from the outlet 24.

Moreover, the air that has flowed into the drain trap 1 together with the drain remains in the upper part of the first storage chamber 22. At this time, unless the temperature of the air is quite high, the amount of expansion of the third valve body 51 is small, and the third valve body 51 remains separated from the third valve seat 52. In other words, the third valve mechanism 50 remains open. Therefore, the air flows out into the second discharge passage 26 via the third valve mechanism 50, passes through the first discharge passage 25, and flows out from the outlet 24.

Further, when the amount of drain flowing into the first storage chamber 22 from the inlet port 21 is greater than the amount of drain flowing out from the first valve mechanism 30, the drain accumulates up to the upper part in the first storage chamber 22. Then, the temperature of the third valve body 51 approaches the temperature of the drain, but even in this case, the amount of expansion of the third valve body 51 is small, and the third valve body 51 remains separated from the third valve seat 52. . Therefore, the drain flows out into the second discharge passage 26 via the third valve mechanism 50, passes through the first discharge passage 25, and flows out from the outlet 24.

On the other hand, when high-temperature, high-pressure steam flows into the first storage chamber 22 from the inlet 21, the drain in the first storage chamber 22 flows out from the first valve mechanism 30 and decreases, and eventually the first valve body 31 is seated on the first valve seat 32. In this way, the first valve mechanism 30 is closed, and steam is prevented from flowing out from the first exhaust hole 33. Further, when steam flows into the first storage chamber 22, the temperature of the third valve body 51 increases. Then, the third valve body 51 expands and seats on the third valve seat 52. In this way, the third valve mechanism 50 is closed, and steam is prevented from flowing out from the third exhaust hole 53.

In this way, during operation, the drain trap 1 allows the high-temperature drain and air that has flowed in to flow out downstream, while preventing the flow of steam that has flowed in from flowing out. Further, during operation, the second valve mechanism 40 is maintained in a closed state, and the second storage chamber 23 remains full of drain.

When the operation of the steam system is stopped, the pressure and temperature upstream of the first exhaust hole 33 and the second exhaust hole 43 gradually decrease. Then, when the pressure in the second storage chamber 23 decreases to the pressure Pb at the start of operation, the second valve body 41 rises due to the biasing force of the spring 44 and leaves the second valve seat 42 . In this way, by opening the second valve mechanism 40, the drain accumulated in the second storage chamber 23 is discharged from the second discharge hole 43 to the outside of the casing 10. The second valve mechanism 40 is maintained in the open state until the next start of operation.

As described above, the drain trap 1 (valve device) of the above embodiment includes the casing 10, the first valve mechanism 30, and the second valve mechanism 40. The casing 10 is provided with a drain inlet 21 and drain storage chambers 22 and 23 communicating with the inlet 21. The first valve mechanism 30 includes a first drain hole 33 provided in the storage chambers 22 and 23, and a first valve body 31 (float) that is accommodated in the storage chambers 22 and 23 and opens and closes the first drain hole 33. have. The second valve mechanism 40 is provided in the storage chambers 22 and 23, and is housed in the second drain hole 43 of the drain having a hole diameter larger than the first drain hole 33, and is accommodated in the storage chambers 22 and 23 and directed toward the second drain hole 43. It has a second valve body 41 (valve body) that moves forward and backward to open and close the second discharge hole 43. The second valve mechanism 40 is provided on the opposite side of the second valve body 41 from the second discharge hole 43 side, and has a spring 44 that biases the second valve body 41 in the valve opening direction. 23 rises to a predetermined value (pressure Pa during operation), the second valve body 41 moves forward against the biasing force of the spring 44 to close the second discharge hole 43. There is.

According to the above configuration, the second valve mechanism 40 can reliably open the valve at the start of operation and close it at the time of operation. Therefore, at the start of operation, a large amount of low-temperature condensate and air remaining in the steam system can be quickly discharged. Therefore, it is possible to prevent water hammer that may occur due to mixing of steam with low-temperature drain.

Further, since the spring 44 is provided on the side opposite to the second discharge hole 43 side of the second valve body 41, the spring 44 is provided on the side opposite to the second discharge hole 43 side. The diameter of the second discharge hole 43 (the diameter of the orifice) can be increased. In other words, when a spring is installed between the second valve body and the second discharge hole, it is necessary to secure a mounting space for the end of the spring on the outer periphery of the second discharge hole. The pore size of the pores is limited. In this way, in the embodiment described above, since the diameter of the second discharge hole 43 can be increased, the residual drain can be discharged more quickly at the start of operation.

In the drain trap 1 of the embodiment described above, the storage chambers include a first storage chamber 22 that communicates with the inflow port 21 and is provided with the first valve mechanism 30, and a first storage chamber that is provided below the first storage chamber 22. It has a second storage chamber 23 that communicates with the storage chamber 22 and is provided with a second valve mechanism 40 .

According to the above configuration, since the two valve mechanisms 30 and 40 are provided in the respective storage chambers 22 and 23, the first valve, which is a float, is The body 31 can be freely accommodated in the storage chamber without worrying about interference with the second valve mechanism 40.

Furthermore, since the second storage chamber 23 is provided below the first storage chamber 22, the water head of the drain in the first storage chamber 22 is added to the drain in the second storage chamber 23, so that the water head of the drain in the first storage chamber 22 is added to the drain in the second storage chamber 23. The drain discharge capacity of the two-valve mechanism 40 is increased.

Furthermore, in the drain trap 1 of the embodiment described above, the second discharge hole 43 opens in the vertical direction at the bottom of the second storage chamber 23. The second valve body 41 is formed into a disk shape and is arranged above the second discharge hole 43 . The spring 44 is provided above the second valve body 41 and urges the second valve body 41 upward.

According to the above configuration, since the second discharge hole 43 is provided at the bottom of the second storage chamber 23, the water head of the drain in the second storage chamber 23 can be increased as much as possible, and the drain by the second valve mechanism 40 can be has a higher discharge capacity. Further, since the second valve body 41 is a so-called disc-shaped valve body, the installation space for the second valve mechanism 40 can be reduced compared to, for example, a spherical float.

Further, in the drain trap 1 of the embodiment described above, one end of the spring 44 is connected to the upper surface of the second valve body 41. The second valve mechanism 40 has a support member 45 that is provided above the spring 44 in the second storage chamber 23 and to which the other end of the spring 44 is connected. The support member 45 also serves as a baffle plate that prevents the drain flowing down from the first storage chamber 22 to the second storage chamber 23 from hitting the upper surface of the second valve body 41.

According to the above configuration, when the second valve mechanism 40 is in the open state, shaking of the second valve body 41 that may occur when drain flowing down from the first storage chamber 22 hits the upper surface of the second valve body 41 is prevented. can do. If the second valve body 41 swings irregularly, the flow of drain toward the second discharge hole 43 may be disturbed, which may impair the drain discharge efficiency. This can be prevented by In this way, since the support member 45 also serves as a baffle plate, there is no need to separately provide a baffle plate.

Further, in the drain trap 1 of the above embodiment, the support member 45 is provided so that its vertical position can be changed. According to this configuration, the biasing force of the spring 44 can be adjusted in accordance with changes in the operating conditions of the steam system.

That is, when the pressure Pa during operation or the pressure Pb at the start of operation is changed, the spring 44 is set so that the second valve mechanism 40 opens and closes appropriately under the changed pressures Pa and Pb. The urging force of can be adjusted. For example, to decrease the biasing force of the spring 44, the position of the support member 45 is shifted downward, and to increase the biasing force of the spring 44, the position of the support member 45 is shifted upward.

The second valve body 61 is a hollow spherical float, and corresponds to the valve body according to the claims of the present application. The second valve body 61 is accommodated in the second storage chamber 29 so as to be movable up and down along the guide portion 15a. The second valve body 61 is arranged above a second discharge hole 63, which will be described later, and opens and closes the second discharge hole 63 by moving up and down.

(Other embodiments)
The drain trap 1 of the above embodiment may have the following configuration.

For example, in the drain trap 1 of the above embodiment, the second valve body 41 is formed into a disk shape, but instead of this, the second valve body may be formed by a spherical float. .

Further, the drain trap 1 of the above embodiment is not limited to a steam trap that prevents the outflow of steam, but may be an air trap that prevents the outflow of air, a gas trap that prevents the outflow of gas, or the like.

Further, in the above embodiment, the drain trap 1 has been described as an example of a valve device, but the valve device of the present application can also be used, for example, as a pressure reducing valve that adjusts the pressure of steam or a gas-liquid separator that separates drain and air. Can be applied.

The technology disclosed in this application is useful for valve devices.

1 Drain trap (valve device)
10 Casing 21 Inflow port 22 First storage chamber (storage chamber)
23 Second storage chamber (storage chamber)
30 First valve mechanism 31 First valve body (float)
33 First discharge hole 40 Second valve mechanism 41 Second valve body (valve body)
43 Second discharge hole 44 Spring 45 Support member

Claims (5)

a casing provided with a liquid inlet and an outlet , and a liquid storage chamber communicating with the inlet;
a first valve mechanism provided in the storage chamber and having a first liquid discharge hole communicating with the outflow port ; a first valve mechanism that is accommodated in the storage chamber and has a float that opens and closes the first discharge hole;
a second discharge hole for liquid provided in the storage chamber and communicating with the outside of the casing instead of the outlet and having a hole diameter larger than the first discharge hole; a second valve mechanism having a valve body that moves forward and backward to open and close the second discharge hole;
The second valve mechanism is provided on a side of the valve body opposite to the second discharge hole, and includes a spring that biases the valve body in a valve-opening direction, and the second valve mechanism has a spring that biases the valve body in a valve opening direction when the pressure in the storage chamber reaches a predetermined value. The valve device is characterized in that when the pressure rises, the valve body moves forward against the biasing force of the spring to close the second discharge hole. The valve device according to claim 1,
The storage chamber is
a first storage chamber that communicates with the inflow port and is provided with the first valve mechanism;
A valve device comprising: a second storage chamber provided below the first storage chamber, communicating with the first storage chamber, and provided with the second valve mechanism. The valve device according to claim 2,
The second discharge hole is open in the vertical direction at the bottom of the second storage chamber,
The valve body is formed in a disc shape and is arranged above the second discharge hole,
The valve device is characterized in that the spring is provided above the valve body and urges the valve body upward. The valve device according to claim 3,
one end of the spring is connected to the upper surface of the valve body,
The second valve mechanism is provided above the spring in the second storage chamber, and has a support member to which the other end of the spring is connected,
The valve device according to claim 1, wherein the support member also serves as a baffle plate that prevents liquid flowing down from the first storage chamber to the second storage chamber from hitting the upper surface of the valve body. The valve device according to claim 4,
The valve device is characterized in that the support member is provided so that its vertical position can be changed.

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