JP7140585B2 - drain trap - Google Patents

Description

The technology disclosed herein relates to drain traps.

For example, in Patent Document 1, a valve body formed in a valve seat for opening and closing a fluid inlet and a fluid outlet is accommodated in a valve chamber, and when drain flows into the valve chamber through the inlet, A drain trap is disclosed in which the valve body is opened and the valve body is closed by the pressure of the steam in the valve chamber when the steam flows into the valve chamber through the inflow port. In this drain trap, an introduction chamber ("cave chamber A" in Patent Document 1) into which fluid is introduced upstream of the valve chamber is interposed between the outside of the casing and the valve chamber. It is formed in a partitioned state.

When the drain flows into the drain trap, the valve body opens to allow the drain to flow out. On the other hand, when steam flows in, the steam flows into the valve chamber, the valve body closes, and the outflow of steam is prevented. At this time, steam is also introduced into the introduction chamber. The valve chamber is kept warm by the steam in the introduction chamber, thereby suppressing condensation of the steam in the valve chamber and thus suppressing pressure drop in the valve chamber. This keeps the valve closed.

Japanese Patent Publication No. 36-3782

However, although the introduction chamber is separated from the outside air, it can be affected by the outside environment. For example, in the drain trap of Patent Document 1, the introduction chamber is separated from the outside air by the outer cover. and the vapor in the introduction chamber can condense. When the generated drain adheres to the partition wall separating the introduction chamber and the valve chamber, the steam in the valve chamber can be cooled by the drain. When the steam inside the valve chamber is cooled, the temperature inside the valve chamber drops, and there is a risk that the valve body will open.

The technology disclosed herein has been made in view of this point, and its purpose is to reduce the influence of the external environment and maintain the valve closed state.

The technology disclosed herein includes a casing in which an inflow port for inflowing fluid, an outflow port for outflowing fluid, and a valve chamber are formed; A drain trap comprising: a valve seat having an outlet through which fluid flows out; and a valve element accommodated in the valve chamber and opening and closing the inlet and the outlet, wherein the valve element The valve is opened when steam flows into the valve chamber through the inflow port, and is closed by the pressure of the steam in the valve chamber when steam flows into the valve chamber through the inflow port. is formed so that an introduction chamber which is separated from the valve chamber by a partition wall and into which a fluid upstream of the valve chamber is introduced is interposed between the outside of the casing and the valve chamber, and In the chamber, a cover is provided to cover the partition wall for suppressing adhesion of drain condensed in the introduction chamber to the partition wall.

According to the drain trap, it is possible to reduce the influence of the external environment and maintain the valve closed state.

FIG. 1 is a cross-sectional view of a drain trap. FIG. 2 is an enlarged sectional view of the drain trap centering on the valve chamber. FIG. 3 is an enlarged sectional view of the drain trap corresponding to FIG. 2 in the valve open state. FIG. 4 is an enlarged sectional view of the drain trap corresponding to FIG. 2 in the valve closed state.

Exemplary embodiments are described in detail below on the basis of the drawings. FIG. 1 is a cross-sectional view of the drain trap 100. FIG. FIG. 2 is an enlarged sectional view of the drain trap 100 centering on the valve chamber 13. As shown in FIG.

Drain trap 100 is incorporated into a steam system, for example. Drain (condensate) generated by condensation of steam and steam can flow into the drain trap 100 . The drain trap 100 automatically discharges only the drain and prevents the outflow of steam. The drain trap 100 includes an inflow port 11 for inflow of fluid, an outflow port 12 for outflow of fluid, a casing 1 in which a valve chamber 13 is formed, a valve seat 5, and a valve body 6 housed in the valve chamber 13. It has

The casing 1 has a casing body 2, an inner lid 3 attached to the casing body 2 and at least partially partitioning the valve chamber 13, and an outer lid 4 attached to the casing body 2 so as to cover the inner lid 3. is doing.

The casing body 2 is formed with an inflow port 11 , an outflow port 12 , a cylindrical wall 21 having a recess 14 for the valve chamber 13 , an inflow passage 15 and an outflow passage 16 .

The inflow path 15 connects the inflow port 11 and the recess 14 (that is, the valve chamber 13). The inflow path 15 is a flow path through which fluid from the inflow port 11 to the valve chamber 13 flows. A screen chamber 17 for accommodating a screen 18 is formed in the middle of the inflow path 15 . The screen 18 is formed in a substantially cylindrical shape. The casing body 2 has an opening for installing the screen 18 from the outside in the screen chamber 17 , and the opening is closed by a plug 19 . The outflow path 16 connects the outflow port 12 and the recess 14 (that is, the valve chamber 13). The outflow path 16 is a flow path through which fluid flows from the valve chamber 13 toward the outflow port 12 .

The cylindrical wall 21 is formed so as to open upward at the upper portion of the casing body 2 . A recess 14 is formed inside the cylindrical wall 21 . The recessed portion 14 is open upward and is formed in a bottomed shape. The cross section of the recess 14 is substantially circular. A female screw is formed on the inner peripheral surface of the cylindrical wall 21 . A male screw is formed on the outer peripheral surface of the cylindrical wall 21 . The cylindrical wall 21 functions as a mounting portion for the inner lid 3 and as a mounting portion for the outer lid 4 . The downstream end of the inflow passage 15 opens at substantially the center of the bottom of the recess 14 . Also, the upstream end of the outflow passage 16 opens at a position eccentric from the center of the recess 14 . The upper end of the recess 14 is closed by the inner lid 3 .

The inner lid 3 has a ceiling portion 31 and a peripheral wall portion 32 extending downward from the peripheral portion of the ceiling portion 31, as shown in FIG. The ceiling portion 31 is formed in a substantially disc shape. The peripheral wall portion 32 is formed in a substantially cylindrical shape. A male screw corresponding to the female screw of the cylindrical wall 21 is formed on the outer peripheral surface of the peripheral wall portion 32 . The inner lid 3 is attached to the casing body 2 by screwing the peripheral wall portion 32 onto the cylindrical wall 21 . The inner lid 3 partitions a portion of the valve chamber 13 .

The outer lid 4 has a ceiling portion 41 and a peripheral wall portion 42 extending downward from the peripheral portion of the ceiling portion 41, as shown in FIG. The ceiling portion 41 is formed in a substantially disc shape. The peripheral wall portion 42 is formed in a substantially cylindrical shape. A female thread corresponding to the male thread of the cylindrical wall 21 is formed on the inner peripheral surface of the peripheral wall portion 42 . The outer lid 4 is attached to the casing main body 21 by screwing the peripheral wall portion 42 onto the cylindrical wall 21 . At this time, the outer wall 4 covers the inner lid 3 from the outside.

The casing 1 is formed with an introduction chamber 22 into which the fluid on the upstream side of the valve chamber 13 is introduced. The introduction chamber 22 is defined by the casing main body 2 , the inner lid 3 and the outer lid 4 . The introduction chamber 22 is formed so as to be interposed between the outside of the casing 1 and the valve chamber 13 . Specifically, the introduction chamber 22 is positioned generally above the valve chamber 13 . The outside of the outer lid 4 is the outside of the casing 1 . The introduction chamber 22 is separated from the valve chamber 13 by the inner lid 3 (in particular, the ceiling portion 31). The inner lid 3 functions as a partition wall separating the valve chamber and the introduction chamber. The upper end surface 21 a of the cylindrical wall 21 forms the bottom of the introduction chamber 22 .

The cylindrical wall 21 is formed with an introduction path 23 for introducing the fluid upstream of the valve chamber 13 into the introduction chamber 22 and a discharge path 24 for discharging the fluid from the introduction chamber 22 . The introduction path 23 branches off from the inflow path 15 and connects the inflow path 15 and the introduction chamber 22 . The lead-out path 24 connects the introduction chamber 22 and the inflow path 24 so as to merge with the inflow path 15 . In the inflow path 15 , the downstream end (that is, the confluence end) of the lead-out path 24 is positioned downstream from the upstream end (that is, the branch end) of the introduction path 23 . Specifically, the upstream end of the introduction passage 23 is positioned upstream of the screen 18 in the inlet passage 15 , and the downstream end of the outlet passage 24 is positioned downstream of the screen 18 in the inlet passage 15 . In other words, since the pressure of the fluid flowing through the inflow passage 15 is higher at the upstream end of the introduction passage 23 than at the downstream end of the discharge passage 24, part of the fluid flowing through the inflow passage 15 is removed from the inflow passage 15. It flows through the introduction path 23 , the introduction chamber 22 , and the outlet path 24 in this order, and returns to the inflow path 15 . The downstream end of the introduction passage 23 and the upstream end of the discharge passage 24 are opened to the upper end surface 21 a of the cylindrical wall 21 .

The valve seat 5 is formed in a substantially columnar shape extending in the vertical direction. An inlet 51 is formed through the valve seat 5 coaxially with the axis of the cylinder. An outflow port 52 is formed through the valve seat 5 at a position eccentric from the axis. One end surface (upper end surface) of the valve seat 5 in the axial direction serves as a seat surface 53 on which the valve element 6 is seated. An annular groove 54 centered on the axis is formed in the seat surface 53 . The upstream end of the outflow port 52 opens into the groove 54 . A flange 55 is formed on the edge portion of the valve seat 5 opposite to the seat surface 53 . A tapered surface 56 is formed on the flange 55 . The tapered surface 56 widens so as to increase in diameter downward.

The valve seat 5 is arranged in the recess 14 so that the flange 55 contacts the bottom of the recess 14 of the casing body 2 . The valve seat 5 is fixed within the recess 14 by sandwiching the flange 55 between the peripheral wall portion 32 of the inner lid 3 attached to the cylindrical wall 21 and the bottom of the recess 14 . At this time, the inflow port 51 communicates with the downstream end of the inflow passage 15 of the casing body 2 , and the outflow port 52 communicates with the upstream end of the outflow passage 16 of the casing body 2 . A valve chamber 13 is defined by the inner lid 3 and the valve seat 5 .

The valve body 6 is accommodated in the valve chamber 13 . The valve body 6 is movable within the valve chamber 13 and opens and closes the inflow port 51 and the outflow port 52 of the valve seat 5 . The valve body 6 is formed in a substantially disk shape. That is, the valve body 6 is a disc valve. The outer diameter of the valve body 6 is smaller than the inner diameter of the peripheral wall portion 32 of the inner lid 3 and larger than the outer diameter of the seat surface 53 of the valve seat 5 . When the valve body 6 is seated on the seat surface 53 , the outer peripheral edge of the valve body 6 protrudes outside the seat surface 31 .

A substantially cylindrical space 26 is formed between the peripheral wall portion 32 of the inner lid 3 and the outer peripheral surface of the valve seat 5 . This space 26 is provided with a bimetal ring 71 and a support ring 72 . Since the space 26 is a space connected to the valve chamber 13 , it is filled with the same fluid as the inside of the valve chamber 13 .

The bimetal ring 71 has a substantially cylindrical shape, and a slit is formed in a part of the circumferential direction over the entire axial direction. That is, the bimetal ring 71 is formed to have a substantially C-shaped cross section. The bimetal ring 71 is formed by bonding together two metal plates having different coefficients of thermal expansion. The diameter of the bimetal ring 71 changes according to its temperature. Specifically, the bimetal ring 71 deforms so that its diameter becomes smaller when the temperature is low, and deforms so that the diameter becomes larger when the temperature is high. The bimetal ring 71 moves on the tapered surface 56 of the valve seat 5 as the diameter changes. Specifically, the bimetal ring 71 moves upward along the tapered surface 56 as its diameter becomes smaller. On the other hand, as the diameter of the bimetal ring 71 increases, it moves downward along the tapered surface 56 .

The support ring 72 is formed in a substantially annular shape. The inner diameter of the support ring 72 is larger than the diameter of the outer peripheral surface of the valve seat 5 (the portion other than the flange 55). A support ring 72 rests on the upper end of the bimetallic ring 71 and is positioned around the upper end of the valve seat 5 . A gap is formed between the support ring 72 and the outer peripheral surface of the valve seat 5 . The support ring 72 moves up and down together with the bimetal ring 71 as the diameter of the bimetal ring 71 changes. The support ring 72 protrudes above the seat surface 53 of the valve seat 5 when the bimetal ring 71 is moved to the uppermost position. In this state, the valve body 6 cannot be seated on the seat surface 53 and a gap is formed between the valve body 6 and the seat surface 53 . On the other hand, when the bimetal ring 71 moves to the lowest position, the support ring 72 does not protrude upward from the seat surface 53 and the valve body 6 can be seated on the seat surface 53 .

In the assumed temperature range of relatively high-temperature drain and steam flowing into the drain trap 100 during normal operation of the steam system, the diameter of the bimetal ring 71 becomes large and the support ring 72 does not protrude from the seat surface 53. At a temperature lower than the temperature range (for example, the assumed ambient temperature), the two metal plates of the bimetallic ring 71 are displaced such that the diameter of the bimetallic ring 71 is reduced and the support ring 72 protrudes from the seat surface 53 . are sorted.

In the introduction chamber 22, a cover 8 is provided so as to cover the inner lid 3, which suppresses the adhesion of the condensate generated in the introduction chamber 22 to the inner lid 3 (more specifically, the ceiling portion 31). ing. The cover 8 is formed in a substantially disc shape. The outer diameter of the cover 8 is larger than the outer diameter of the ceiling portion 31 of the inner lid 3 . The cover 8 is positioned above the ceiling portion 31 and attached to the outer lid 4 with a gap between it and the ceiling portion 31 . At this time, the cover 8 covers the entire surface of the ceiling portion 31 .

For example, when steam is introduced into the introduction chamber 22 and the outer lid 4 is cooled by the outside air, wind and rain outside the casing 1, the steam in the introduction chamber 22 may condense. Even if the drain condensed in the vicinity of the outer lid 4 falls, it falls on the cover 8 and is prevented from adhering to the ceiling portion 31 .

Next, the operation of the drain trap 100 configured as described above will be described. FIG. 3 is an enlarged sectional view of the drain trap 100 corresponding to FIG. 2 in the valve open state. FIG. 4 is an enlarged sectional view of the drain trap 100 corresponding to FIG. 2 in the valve closed state. 1 and 2 show the forced valve opening state of the valve body 6. FIG.

When the steam system is stopped, the inside of the drain trap 100 is at a low temperature, and the bimetal ring 71 is also at a low temperature. Therefore, as shown in FIG. 2, the diameter of the bimetal ring 71 is reduced and the bimetal ring 71 is raised. Accordingly, the support ring 72 protrudes above the seat surface 53 of the valve seat 5 . The valve body 6 rests on the support ring 72 and a gap is formed between the valve body 6 and the seat surface 53 . That is, the valve body 6 is forced to open by the support ring 72 .

When the operation of the steam system is started from this state, the initial air or low-temperature drain smoothly flows into the valve chamber 13 from the inlet 51 . The initial air or cold drain then exits the drain trap 100 via the outlet 52 , the outlet passage 16 and the outlet port 12 . As the initial air or the low-temperature drain flows, the valve body 6 is pushed up, and the inlet 51 and the outlet 52 are largely opened.

Here, the valve chamber 13 and the space 26 are in communication. Therefore, when the drain temperature gradually rises, the bimetal ring 71 is heated. As a result, the diameter of the bimetal ring 71 increases, and the bimetal ring 71 descends along the tapered surface 56 as shown in FIG. Accordingly, the support ring 72 is lowered to a position where it does not project upward from the seat surface 53 . That is, the support ring 72 moves to a position where it does not affect the opening and closing of the valve body 6 .

Part of the drain flowing through the inflow passage 15 is introduced into the introduction chamber 22 via the introduction passage 23 . The introduction chamber 22 is filled with drain. Drain from the introduction chamber 22 flows out to the inflow passage 15 through the outlet passage 24 .

After that, when steam flows into the drain trap 100 , the steam flows into the valve chamber 13 via the inflow port 11 , the inflow passage 15 and the inflow port 51 . The steam that has flowed into the valve chamber 13 flows out through the outflow port 52 . At this time, steam flows at high speed along the lower surface of the valve body 6, and a low pressure region is generated below the valve body 6 according to Bernoulli's theorem. Furthermore, the steam also flows above the valve body 6 in the valve chamber 13 and is compressed to create a high pressure area above the valve body 6 . Due to this pressure relationship, the valve body 6 is pushed down and seated on the seat surface 53 as shown in FIG. In this valve closed state, the inside of the valve chamber 13 is filled with relatively high-pressure steam, and this pressure acts on the upper surface of the valve body 6 . On the other hand, the pressure of the steam inside the inlet 51 acts on the portion of the lower surface of the valve body 6 that closes the inlet 51 . The pressure of the steam in the valve chamber 13 is higher than that in the inlet 51, and the pressure of the steam in the inlet 51 is higher in the area of the portion of the valve body 6 on which the pressure of the steam in the valve chamber 13 acts. Since the area of the valve body 6 is larger than the area of the acting portion, the valve body 6 is pressed against the seat surface 53 by the steam in the valve chamber 13, and the valve closed state is maintained.

Here, part of the steam flowing through the inflow path 15 is introduced into the introduction chamber 22 via the introduction path 23 . The introduction chamber 22 is filled with steam. Steam in the introduction chamber 22 flows out to the inflow passage 15 through the outlet passage 24 . In the closed state, the introduction chamber 22 does not communicate with the valve chamber 13 . Since the introduction chamber 22 is arranged so as to be interposed between the outside of the casing 1 and the valve chamber 13, the influence of the external environment of the casing 1 on the valve chamber 13 is reduced. Specifically, if the inner lid 3 is exposed to the external environment, if the inner lid 3 is cooled by the outside air or wind and rain, the steam in the valve chamber 13 will be cooled and condensed, and the closed state of the valve will be maintained. may not be possible. On the other hand, the provision of the introduction chamber 22 prevents the inner lid 3 from being exposed to the external environment. This suppresses the temperature drop of the steam in the valve chamber 13 . In addition, since steam is introduced into the introduction chamber 22, the steam in the valve chamber 13 is kept warm. This also suppresses the temperature drop of the steam in the valve chamber 13 .

Since the outer lid 4 is exposed to the external environment of the casing 1, it is affected by outside air or wind and rain. When the outer cover 4 is cooled by the outside air or the weather, the steam in the introduction chamber 22 may be cooled and condensed. In this case, the generated drain is led out from the outlet passage 24 to the inflow passage 15 , and the steam in the inflow passage 15 is introduced from the introduction passage 23 . That is, while steam is present in the inflow passage 15 (more specifically, while steam is present in the portion of the introduction passage 15 where the upstream end of the introduction passage 23 is located), even if the steam in the introduction chamber 22 is condensed, The introduction chamber 22 is replenished with steam. In this way, the valve closed state is maintained for a long period of time.

When drain flows into the drain trap 100 with the valve body 6 closed, the inlet 51 is filled with the drain. Since the valve seat 5 and the valve body 6 are cooled by the drain, the steam in the valve chamber 13 is also cooled, and the pressure in the valve chamber 13 decreases. When the force pushing down the valve body 6 by the steam in the valve chamber 13 becomes smaller than the force pushing up the valve body 6 by the drain of the inflow port 51, the valve body 6 is pushed up by the drain to open the valve. As a result, the drain quickly flows out of the drain trap 100 .

At this time, part of the drain flowing through the inflow passage 15 is introduced into the introduction chamber 22 through the introduction passage 23 as described above. The drain introduced into the introduction chamber 22 cools the inner lid 3 . This promotes the cooling of the steam in the valve chamber 13, which in turn promotes the opening of the valve.

In this manner, the drain trap 100 allows drain to flow out while preventing steam from flowing out.

Here, since the introduction chamber 22 is provided with the cover 8, the closed state of the valve body 6 is maintained for a longer period of time. Specifically, the outer lid 4 is exposed to the external environment as described above. As the outer lid 4 is cooled by the external environment, the vapor in the introduction chamber 22 is also cooled and may thus condense. Condensation of steam tends to occur in the vicinity of the outer cover 4, and the generated drain adheres to the inner surface of the outer cover 4 or drips as it is. At this time, the cover 8 is arranged above the inner lid 3 to prevent the drain from falling onto the inner lid 3 , especially the ceiling portion 31 . The drain that has fallen onto the cover 8 falls from the periphery of the cover 8. - 特許庁Since the cover 8 covers the entire surface of the ceiling portion 31 of the inner lid 3 , the drain dropping from the cover 8 falls on the outer peripheral side of the ceiling portion 31 , that is, the upper end surface of the cylindrical wall 21 of the casing body 2 . The drain that has dropped onto the upper end surface of the cylindrical wall 21 is led out to the inflow channel 15 via the lead-out channel 24 . Thus, even if drainage occurs in the introduction chamber 22, the amount of drainage that adheres to the inner lid 3 is reduced. This suppresses the cooling of the inner lid 3 by the drain, and thus the cooling of the steam in the valve chamber 13 is suppressed. As a result, the valve closed state is maintained for a longer period of time.

In addition, the cover 8 and the ceiling portion 31 are not in contact. Therefore, even if the cover 8 is cooled by the drain, cooling of the ceiling portion 31 by the cover 8 is suppressed.

On the other hand, since a gap is formed between the cover 8 and the ceiling portion 31, when the drain flows into the drain trap 100, the drain introduced into the introduction chamber 22 flows between the cover 8 and the ceiling portion 31. . In other words, the cover 8 does not hinder the cooling of the ceiling portion 31 by the drain. Therefore, the valve body 6 can be quickly switched from the valve closed state to the valve open state.

As described above, the drain trap 100 includes an inflow port 11 through which fluid flows in, an outflow port 12 through which fluid flows out, a casing 1 in which a valve chamber 13 is formed, and an inflow port 51 through which fluid flows into the valve chamber 13. , and a valve seat 5 formed with an outlet 52 through which fluid flows out from the valve chamber 13; is opened when drain flows into the valve chamber 13 through the inflow port 51, and is closed by the steam pressure in the valve chamber 13 when steam flows into the valve chamber 13 through the inflow port 51. The casing 1 has an introduction chamber 22 which is separated from the valve chamber 13 by the inner lid 3 (partition wall) and into which the fluid upstream of the valve chamber 13 is introduced. A cover 8 is provided in the introduction chamber 22 so as to be interposed therebetween and covers the inner lid 3 for suppressing the adhesion of the condensate generated in the introduction chamber 22 to the inner lid 3 . .

With this configuration, the fluid that has flowed into the casing 1 through the inflow port 11 can flow into the valve chamber 13 through the inflow port 51 . Fluid in the valve chamber 13 can flow out of the valve chamber 13 via the outlet 51 and out of the casing 1 via the outflow port 12 . When the fluid is drain, the valve body 6 opens to allow the drain to pass through the valve chamber 13 . On the other hand, when the fluid is steam, the valve body 6 closes to prevent steam from passing through the valve chamber 13 . In other words, the drain trap 100 prevents steam from flowing out while allowing drain to flow out.

Here, the introduction chamber 22 is formed so as to be interposed between the outside of the casing 1 and the valve chamber 13 , and the fluid on the upstream side of the valve chamber 13 is introduced into the introduction chamber 22 . When steam is flowing into the casing 1, the valve chamber 13 is filled with steam, the valve body 6 is closed, and the introduction chamber 22 is filled with steam. The valve chamber 13 is isolated from the external environment by an introduction chamber 22 filled with steam and is kept warm by the steam in the introduction chamber 22 . As a result, the temperature drop of the steam in the valve chamber 13 is suppressed, and the valve closed state is maintained for a long period of time. In addition, the introduction chamber 22 is provided with a cover 8 so as to cover the inner lid 3 for suppressing adhesion of the condensate generated in the introduction chamber 22 to the inner lid 3 . Even if the introduction chamber 22 is affected by the external environment and the steam in the introduction chamber 22 is condensed, the cover 8 prevents the drain from adhering to the inner lid 3 . Therefore, the inner lid 3 is prevented from being cooled by the condensed drain in the introduction chamber 22 . In this way, the influence of the external environment of the casing 1 on the valve chamber 13 can be reduced, and the closed state of the valve can be further maintained.

Further, the cover 8 is positioned above the inner lid 3 with a gap between it and the inner lid 3 . Here, the "state having a gap" means not only a state in which two members are completely non-contact but also a state in which two members are partially connected and a gap is formed in other portions. is.

According to this configuration, heat conduction between the cover 8 and the inner lid 3 is prevented in the portion where the gap is formed. As a result, even if the cover 8 is cooled by the condensed drain in the introduction chamber 22 , the cover 8 prevents the inner lid 3 and, by extension, the steam in the valve chamber 13 from being cooled. On the other hand, when the drain begins to flow into the casing 1 while the valve body 6 is in the closed state, the drain is introduced into the introduction chamber 22 . The drain flows into the gap between the cover 8 and the inner lid 3 to cool the inner lid 3. This promotes cooling of the steam in the valve chamber 13 and, in turn, promotes opening of the valve body 6 .

Further, the casing 1 includes an introduction passage 23 that branches off from an inflow passage 15 through which fluid flows from the inflow port 11 toward the valve chamber 13 and introduces the fluid upstream of the valve chamber 13 into the introduction chamber 22; An outlet passage 24 is formed to join the fluid in the chamber 22 to the inflow passage 15 , and the downstream end of the outlet passage 24 is located downstream of the upstream end of the introduction passage 23 in the inflow passage 15 .

According to this configuration, in the inflow passage 15, the pressure at the upstream end portion of the introduction passage 23 is higher than that at the downstream end portion of the discharge passage 24, so the introduction passage 23, the introduction chamber 22, and the discharge passage 24 are arranged in this order. A fluid flow is formed. When the steam in the introduction chamber 22 is condensed, the steam in the inflow passage 15 is introduced into the introduction chamber 22 through the introduction passage 23, and the drain in the introduction chamber 22 is led out to the inflow passage 15 through the outlet passage 24. . Therefore, even if the introduction chamber 22 is affected by the external environment, the state in which the introduction chamber 22 is filled with steam is maintained for a while.

Specifically, the casing 1 includes a casing body 2 formed with an inflow port 11 and an outflow port 12, an inner lid 3 attached to the casing body 2 and at least partially partitioning a valve chamber 13, and an inner lid 3. It has an outer lid 4 that partitions an introduction chamber 22 together with the casing body 2 and the inner lid 3, and the partition wall is formed by the inner lid 3.

According to this structure, the simple structure of attaching the inner lid 3 and the outer lid 4 to the casing body 2 intervenes between the outside of the casing 1 and the valve chamber 13, and is separated from the valve chamber 13 by the partition wall. An introduction chamber 22 can be formed.

Also, the cover 8 is provided on the outer lid 4 and is not in contact with the inner lid 3 .

According to this configuration, even if the cover 8 is cooled by the condensed condensate in the introduction chamber 22, the cover 8 further prevents the inner lid 3 and, by extension, the steam in the valve chamber 13 from being cooled. .

<<Other embodiments>>
As described above, the embodiments have been described as examples of the technology disclosed in the present application. However, the technology in the present disclosure is not limited to this, and can be applied to embodiments in which modifications, replacements, additions, omissions, etc. are made as appropriate. Moreover, it is also possible to combine the constituent elements described in the above embodiments to create new embodiments. In addition, among the components described in the attached drawings and detailed description, there are not only components essential for solving the problem, but also components not essential for solving the problem in order to exemplify the above technology. can also be included. Therefore, it should not be immediately recognized that those non-essential components are essential just because they are described in the attached drawings and detailed description.

For example, the casing 1 has a casing body 2, an inner lid 3 and an outer lid 4, but is not limited to this. The casing 1 may adopt any configuration as long as an inflow port, an outflow port, a valve chamber and an introduction chamber are formed. The valve chamber 13 and the introduction chamber 22 are formed by attaching the inner lid 3 and the outer lid 4 to the casing body 2, but are not limited to this.

The cover 8 covers the entire surface of the ceiling portion 31 of the inner lid 3, but is not limited to this. The cover 8 may partially cover the ceiling portion 31 . Since the cover 8 can reduce the adhesion of drainage to the portion of the ceiling 31 covered by the cover 8 , cooling of the ceiling 31 by the drainage can be suppressed within that limit.

Also, the cover 8 is attached to the outer lid 4, but may be attached to the inner lid 3, for example. For example, a boss may be provided on the ceiling portion 31 and the cover 8 may be attached to the boss. In that case, a gap is formed between the cover 8 and the ceiling portion 31 at portions other than the boss. The cover 8 is thermally connected to the ceiling portion 31 through the bosses, but since the portion to be thermally connected is limited, even if the cover 8 is cooled by the drain, the heat is applied to the ceiling portion 31. Small impact. As another example, the cover 8 may be made of a heat insulating material and attached in contact with the upper surface of the ceiling portion 31 . That is, the upper surface of the ceiling portion 31 is covered with the heat insulating material. Even with such a configuration, cooling of the ceiling portion 31 by drainage generated in the introduction chamber 22 is suppressed.

As described above, the technology disclosed herein is useful for drain traps.

100 Drain trap 1 Casing 11 Inflow port 12 Outflow port 13 Valve chamber 15 Inflow path 2 Casing main body 22 Introduction chamber 23 Introduction path 24 Outlet path 3 Inner lid (partition wall)
4 outer lid 5 valve seat 51 inlet 52 outlet 6 valve body 8 cover

Claims (5)

a casing in which an inflow port for inflow of fluid, an outflow port for outflow of fluid, and a valve chamber are formed;
a valve seat having an inflow port for inflowing fluid into the valve chamber and an outflow port for outflowing fluid from the valve chamber;
a valve body that is housed in the valve chamber and opens and closes the inflow port and the outflow port;
The casing is formed with an inflow path through which fluid flows from the inflow port to the valve chamber,
The valve body opens when drain flows into the valve chamber through the inflow port, and when steam flows into the valve chamber through the inflow port, pressure of steam in the valve chamber causes the valve body to open. close the valve,
In the casing, an introduction chamber is separated from the valve chamber by a partition wall, into which the fluid on the upstream side of the valve chamber is introduced, and which is a space different from the inflow passage. formed to intervene between the valve chamber and
A drain trap provided in the introduction chamber so as to cover the partition wall with a cover that suppresses adhesion of drain condensed in the introduction chamber to the partition wall. In the drain trap of claim 1,
The drain trap positioned above the partition wall with a gap between the cover and the partition wall. In the drain trap according to claim 1 or 2,
The casing has an introduction path that branches off from the inflow path and introduces the fluid upstream of the valve chamber into the introduction chamber, and an outlet path that joins the fluid in the introduction chamber to the inflow path. formed,
In the inflow path, a downstream end of the lead-out path is located downstream of an upstream end of the introduction path. In the drain trap according to any one of claims 1 to 3,
The casing is
a casing body in which the inflow port and the outflow port are formed;
an inner lid attached to the casing body and at least partially defining the valve chamber;
an outer lid attached to the casing body so as to cover the inner lid and partitioning the introduction chamber together with the casing body and the inner lid;
The drain trap, wherein the partition wall is formed by the inner lid. In the drain trap according to claim 4,
A drain trap, wherein the cover is provided on the outer lid and is not in contact with the inner lid.

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