CN219954400U - Drainage valve group - Google Patents

Abstract

The utility model provides a drainage valve group, comprising: the connecting seat is provided with a water inlet and outlet channel and a circulating channel which are communicated with each other; the anti-freezing valve is arranged on the connecting seat and comprises a temperature bulb, a drainage channel and a drainage outlet, the temperature bulb is movably arranged in the drainage channel to open and close the drainage outlet, the maximum distance between one end of the temperature bulb, which faces the connecting seat, and the central line of the water inlet and outlet channel is L1, the maximum distance between the temperature bulb and the central line of the water inlet and outlet channel is less than or equal to 21mm, and the temperature bulb is communicated with the drainage channel when the drainage outlet is opened; the air inlet valve is arranged on the connecting seat and provided with an air inlet which can be opened and closed, and the air inlet is communicated with the circulation channel under the condition of opening; and the electromagnetic valve is arranged on the connecting seat and is used for enabling the communication channel and the drainage channel to be communicated or disconnected. By adopting the scheme, the temperature bulb can be further close to the water inlet and outlet channel, so that heat loss caused by fluid flowing to the temperature bulb is reduced, the temperature difference between the temperature bulb and the water inlet and outlet channel is reduced, the valve opening and closing precision of the anti-freezing valve is ensured, and the anti-freezing capability of the drain valve group is improved.

Description

Drainage valve group

Technical Field

The utility model relates to the technical field of drain valves, in particular to a drain valve group.

Background

At present, along with the wide application of the drainage valve group, the use requirement on the drainage valve group is higher and higher, the drainage valve group in the prior art generally comprises an anti-freezing valve, an electromagnetic valve, an air inlet valve, a connecting seat and the like, wherein the anti-freezing valve is generally positioned below the electromagnetic valve and is far away from a circulating pipeline in the connecting seat, and the heat transfer loss of an intermediate fluid is more, so that the temperature of the fluid flowing to a temperature bag is lower, the difference between the temperature of the fluid at the temperature bag and the temperature of the fluid in a circulating pipeline is larger, and the problem of lower temperature precision of a switch valve can occur.

Disclosure of Invention

The utility model provides a drainage valve group, which aims to solve the problem of lower temperature precision of a switching valve of the drainage valve group in the prior art.

In order to solve the above problems, the present utility model provides a drainage valve set comprising: the connecting seat is provided with a water inlet and outlet channel and a circulating channel which are communicated with each other; the anti-freezing valve is arranged on the connecting seat and comprises a temperature bulb, a drain channel and a drain outlet, the temperature bulb is movably arranged in the drain channel to open and close the drain outlet, the maximum distance between one end of the temperature bulb, which faces the connecting seat, and the central line of the water inlet and outlet channel is L1, the maximum distance between the temperature bulb and the central line of the water inlet and outlet channel is less than or equal to 21mm, and the drain outlet is communicated with the drain channel under the condition that the drain outlet is opened; the air inlet valve is arranged on the connecting seat and provided with an air inlet which can be opened and closed, and the air inlet is communicated with the circulation channel under the condition that the air inlet is opened; and the electromagnetic valve is arranged on the connecting seat and is used for enabling the communication channel and the drainage channel to be communicated or disconnected.

Further, the frost valve is positioned below the water inlet and outlet channel, and the electromagnetic valve and the temperature bulb are staggered in the horizontal direction.

Further, the electromagnetic valve is horizontally arranged, the electromagnetic valve is provided with a first flow port, the first flow port is communicated with the flow channel, and the distance between the center line of the water inlet and outlet channel and the center line of the first flow port is L2, wherein L2 is more than or equal to 16mm.

Further, the air inlet valve is arranged above the water inlet and outlet channel, the air inlet valve is vertically arranged, the electromagnetic valve is arranged below the air inlet valve, the air inlet valve and the electromagnetic valve are arranged on the same side of the center line of the water inlet and outlet channel, the distance between the center line of the air inlet and the center line of the water inlet and outlet channel is L3, and the L3 is more than or equal to 14mm.

Further, the anti-freezing valve further comprises an anti-freezing valve seat, the outer wall of the anti-freezing valve seat is provided with a sealing groove, the drainage valve set further comprises a sealing ring, the sealing ring is located in the sealing groove, the connecting seat comprises a main body and an anti-freezing valve joint connected with the main body, the anti-freezing valve joint is arranged below the main body, the anti-freezing valve seat is arranged on the anti-freezing valve joint, the sealing ring seals the joint of the anti-freezing valve seat and the anti-freezing valve joint, and the drainage channel is arranged in the anti-freezing valve seat.

Further, the anti-freezing valve seat comprises a connecting section and a first transition section which are sequentially connected, the diameter of the first transition section is larger than that of the connecting section, the sealing groove is arranged on the connecting section and is positioned at the joint of the connecting section and the first transition section, and the connecting section is connected with the anti-freezing valve joint.

Further, the air inlet valve comprises an air inlet valve seat, the air inlet valve seat is provided with an air inlet, an air inlet cavity and an air outlet which are sequentially arranged from top to bottom, one end of the air inlet cavity is communicated with the air inlet, the other end of the air inlet cavity is communicated with the air outlet, the air outlet is communicated with the water inlet channel, the upper ends of the water inlet channel and the water outlet channel, and the center line of the water inlet channel and the center line of the air inlet cavity are located on the same axis.

Further, the solenoid valve includes the solenoid valve seat, and the solenoid valve seat has first circulation mouth, solenoid valve circulation chamber and the second circulation mouth of intercommunication each other, and solenoid valve seat and connecting seat are connected, and first circulation mouth is vertical to be set up, and the second circulation mouth level sets up, and the lower extreme and the first circulation mouth intercommunication of circulation passageway, the central line in solenoid valve circulation chamber and the central line of solenoid valve seat are located same axis.

Further, the drainage channel is communicated with the electromagnetic valve circulation cavity, the circulation area of the drainage channel is larger than that of the electromagnetic valve circulation cavity, and the circulation area of the second flow port is smaller than that of the water inlet of the anti-freezing valve.

Further, the anti-freezing valve further comprises an anti-freezing valve core, one end of the temperature bulb is matched with the stop of the anti-freezing valve core, the anti-freezing valve core is movably arranged in the drainage channel, and the temperature bulb opens and closes the drainage port through the anti-freezing valve core; the air inlet valve also comprises an air inlet valve core which is floatably arranged in the air inlet cavity to block or open the air inlet.

Further, the solenoid valve further includes a needle structure openably and closably communicating with the drain passage, the needle structure being movably disposed in a direction approaching or separating from the second flow port to block or open the second flow port.

By applying the technical scheme of the utility model, the utility model provides a drainage valve group, which comprises the following components: the connecting seat is provided with a water inlet and outlet channel and a circulating channel which are communicated with each other; the anti-freezing valve is arranged on the connecting seat and comprises a temperature bulb, a drain channel and a drain outlet, the temperature bulb is movably arranged in the drain channel to open and close the drain outlet, the maximum distance between one end of the temperature bulb, which faces the connecting seat, and the central line of the water inlet and outlet channel is L1, the maximum distance between the temperature bulb and the central line of the water inlet and outlet channel is less than or equal to 21mm, and the drain outlet is communicated with the drain channel under the condition that the drain outlet is opened; the air inlet valve is arranged on the connecting seat and provided with an air inlet which can be opened and closed, and the air inlet is communicated with the circulation channel under the condition that the air inlet is opened; and the electromagnetic valve is arranged on the connecting seat and is used for enabling the communication channel and the drainage channel to be communicated or disconnected. By adopting the scheme, the maximum distance L1 between one end of the temperature bulb facing the connecting seat and the center line of the water inlet and outlet channel is limited in the numerical range, so that the temperature bulb is further close to the water inlet and outlet channel, heat dissipation when fluid flows to the temperature bulb is reduced, temperature difference between the temperature bulb and the water inlet and outlet channel is reduced, the switching valve precision of the anti-freezing valve is ensured, the anti-freezing capability of the water outlet valve is improved, and the problem that the temperature precision of the switching valve of the water outlet valve in the prior art is lower is effectively solved.

Drawings

The accompanying drawings, which are included to provide a further understanding of the utility model and are incorporated in and constitute a part of this specification, illustrate embodiments of the utility model and together with the description serve to explain the utility model. In the drawings:

fig. 1 shows a schematic structural view of a drain valve block provided by an embodiment of the present utility model;

FIG. 2 shows a cross-sectional view of the drain valve block of FIG. 1;

FIG. 3 shows a schematic structural view of the connection base of FIG. 1;

FIG. 4 shows a cross-sectional view of the connection block of FIG. 3;

fig. 5 shows a cross-sectional view of the freeze valve of fig. 1.

Wherein the above figures include the following reference numerals:

10. a connecting seat; 11. a water inlet and outlet passage; 12. a flow channel; 13. a main body; 14. a frost valve joint;

20. an anti-freeze valve; 21. a temperature pack; 22. a drainage channel; 23. a water outlet; 24. an anti-freezing valve seat; 241. sealing grooves; 2411. an inclined surface; 242. a connection section; 243. a first transition section; 244. a second transition section; 245. an extension section; 25. an antifreezing valve core;

30. an intake valve; 31. an intake valve seat; 311. an air inlet; 312. an air inlet cavity; 32. an air inlet valve core;

40. an electromagnetic valve; 41. an electromagnetic valve seat; 411. a first flow port; 412. a solenoid valve flow chamber; 413. a second flow port; 42. a valve needle structure;

50. and (3) sealing rings.

Detailed Description

The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. It will be apparent that the described embodiments are only some, but not all, embodiments of the utility model. The following description of at least one exemplary embodiment is merely exemplary in nature and is in no way intended to limit the utility model, its application, or uses. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

As shown in fig. 1 to 5, an embodiment of the present utility model provides a drainage valve set including: the connecting seat 10, the connecting seat 10 has water inlet and outlet channel 11 and circulation channel 12 communicated with each other; the anti-freezing valve 20 is arranged on the connecting seat 10, the anti-freezing valve 20 comprises a temperature bulb 21, a drain channel 22 and a drain outlet 23, the temperature bulb 21 is movably arranged in the drain channel 22 to open and close the drain outlet 23, the maximum distance between one end of the temperature bulb 21 facing the connecting seat 10 and the central line of the water inlet and outlet channel 11 is L1, L1 is less than or equal to 21mm, and the drain outlet 23 is communicated with the drain channel 22 when the drain outlet 23 is opened; an intake valve 30 provided in the connection base 10, the intake valve 30 having an intake port 311 that can be opened and closed, the intake port 311 communicating with the flow passage 12 when the intake port 311 is opened; a solenoid valve 40 provided on the connection base 10, the solenoid valve 40 for connecting or disconnecting the circulation passage 12 and the drain passage 22.

By adopting the scheme, the maximum distance L1 between one end of the temperature bulb 21 facing the connecting seat 10 and the central line of the water inlet and outlet channel 11 is limited within the numerical range, so that the temperature bulb 21 is further close to the water inlet and outlet channel 11, heat dissipation when fluid flows to the temperature bulb 21 is reduced, the temperature difference between the temperature bulb 21 and the water inlet and outlet channel 11 is reduced, the switching valve precision of the anti-freezing valve 20 is ensured, the anti-freezing capacity of the water drain valve group is improved, and the problem that the switching valve temperature precision of the water drain valve group in the prior art is lower is effectively solved.

Wherein, the frost valve 20 is positioned below the water inlet and outlet channel 11, and the electromagnetic valve 40 and the temperature bulb 21 are staggered in the horizontal direction. The electromagnetic valve 40 and the temperature bulb 21 are staggered in the horizontal direction, so that the anti-freezing valve 20 can be closer to the water inlet and outlet channel 11, the temperature difference between the temperature bulb 21 and the water inlet and outlet channel 11 is reduced, the valve opening and closing precision of the anti-freezing valve 20 is ensured, and the anti-freezing capability of the drain valve group is improved. Wherein, the anti-freezing valve 20 is arranged below the water inlet and outlet channel 11, and the water outlet 23 is arranged at the lower end of the water outlet channel 22, so that the fluid entering the anti-freezing valve 20 can be smoothly discharged under the action of gravity. In this embodiment, the drain opening 23 is located at the lower end of the drain passage 22.

Further, the anti-freezing valve 20 is vertically arranged, the electromagnetic valve 40 is provided with a first flow port 411, the first flow port 411 is communicated with the flow channel 12, and the distance between the center line of the water inlet and outlet channel 11 and the center line of the first flow port 411 is L2, wherein L2 is more than or equal to 16mm. Limiting the distance L2 between the centerline of the water inlet and outlet passage 11 and the centerline of the first flow opening 411 to the above-described vertical range further ensures that the solenoid valve 40 and the bulb 21 can be staggered in the horizontal direction so that the anti-freeze valve 20 is closer to the water inlet and outlet passage 11. In this embodiment, the solenoid valve 40 is horizontally disposed.

Specifically, the air inlet valve 30 is located above the water inlet and outlet channel 11, the air inlet valve 30 is vertically arranged, the electromagnetic valve 40 is located below the air inlet valve 30, the air inlet valve 30 and the electromagnetic valve 40 are located on the same side of the center line of the water inlet and outlet channel 11, and the distance between the center line of the air inlet 311 and the center line of the water inlet and outlet channel 11 is L3, wherein L3 is more than or equal to 14mm. The distance L3 between the center line of the intake port 311 and the center line of the water intake/discharge passage 11 is limited to the above-described vertical range, so that the communication between the inlet flow passage of the intake valve 30 and both the water intake/discharge passage 11 and the electromagnetic valve 40 can be ensured.

Note that L2 and L3 are both horizontal distances.

In this embodiment, the anti-freezing valve 20 further includes an anti-freezing valve seat 24, a sealing groove 241 is provided on the outer wall of the anti-freezing valve seat 24, the drain valve set further includes a sealing ring 50, the sealing ring 50 is located in the sealing groove 241, the connection seat 10 includes a main body 13 and an anti-freezing valve joint 14 connected with the main body 13, the anti-freezing valve joint 14 is disposed below the main body 13, the anti-freezing valve seat 24 is mounted on the anti-freezing valve joint 14, the sealing ring 50 seals the junction between the anti-freezing valve seat 24 and the anti-freezing valve joint 14, and the drain channel 22 is disposed in the anti-freezing valve seat 24. The anti-freezing valve joint 14 is arranged, so that the anti-freezing valve joint is convenient to connect with the anti-freezing valve seat 24; the seal groove 241 is provided on the outer wall of the antifreeze valve seat 24 in order to avoid being scratched by the internal thread of the antifreeze valve joint 14 when the seal ring 50 is assembled.

Among them, the sealing groove 241 has an inclined surface 2411, and the inclined surface 2411 is provided to facilitate assembling the sealing ring 50.

The antifreeze valve seat 24 comprises a connecting section 242 and a first transition section 243 which are sequentially connected, the diameter of the first transition section 243 is larger than that of the connecting section 242, the sealing groove 241 is arranged on the connecting section 242 and is positioned at the joint of the connecting section 242 and the first transition section 243, and the connecting section 242 is connected with the antifreeze valve joint 14. The sealing groove 241 is arranged on the connecting section 242 and is positioned at the joint of the connecting section 242 and the first transition section 243, so that the sealing ring 50 is convenient to place, and meanwhile, the sealing ring can be smoothly installed through a guiding tool, and the sealing ring is prevented from being scratched by the internal thread of the frost valve joint 14.

Optionally, the antifreeze valve seat 24 further includes a second transition section 244 and an extension section 245 connected to each other, the first transition section 243 having a diameter greater than the diameters of the second transition section 244 and the extension section 245, the second transition section 244 being connected to the first transition section 243.

Optionally, the inner wall of the anti-freeze valve joint 14 has an internal thread, the connecting section 242 has an external thread, and the center line of the drain passage 22 and the center line of the anti-freeze valve seat 24 are located on the same axis, and the inner diameter of the anti-freeze valve joint 14 is equal to the minor diameter of the internal thread. The center line of the drain passage 22 and the center line of the antifreeze valve seat 24 are arranged on the same axis, and the inner diameter of the antifreeze valve joint 14 is equal to the minor diameter of the internal thread, so that the flow area can be enlarged, the flow capacity is ensured, the processing procedures are reduced, the processing technology is improved, and the production cost is reduced.

In this embodiment, the intake valve 30 includes an intake valve seat 31, the intake valve seat 31 has an intake port 311, an intake chamber 312 and an air outlet sequentially provided from top to bottom, one end of the intake chamber 312 is communicated with the intake port 311, the other end of the intake chamber 312 is communicated with the air outlet, the air outlet is communicated with the water inlet and outlet passage 11, and the upper ends of the circulation passage 12, and the center line of the circulation passage 12 and the center line of the intake chamber 312 are located on the same axis. The center line of the flow channel 12 and the center line of the air inlet cavity 312 are arranged on the same axis, so that the flow capacity is ensured, and the flow area is enlarged.

Wherein, solenoid valve 40 includes solenoid valve seat 41, and solenoid valve seat 41 has the first circulation mouth 411, solenoid valve circulation chamber 412 and the second circulation mouth 413 of mutual intercommunication, and solenoid valve seat 41 is connected with connecting seat 10, and first circulation mouth 411 is vertical to be set up, and second circulation mouth 413 level sets up, and the lower extreme and the first circulation mouth 411 intercommunication of circulation passageway 12, the central line of solenoid valve circulation chamber 412 and the central line of solenoid valve seat 41 are located the same axis. The center line of the electromagnetic valve circulation chamber 412 and the center line of the electromagnetic valve seat 41 are arranged on the same axis, so that the circulation capacity can be ensured, and the fluid circulation is smoother.

Further, the drain passage 22 communicates with the solenoid valve flow chamber 412, the flow area of the drain passage 22 is larger than the flow area of the solenoid valve flow chamber 412, and the flow area of the second flow port 413 is smaller than the flow area of the water inlet of the anti-freeze valve 20. The flow area of the drain passage 22 is set to be larger than the flow area of the solenoid valve flow chamber 412, and the flow area of the second flow port 413 is set to be smaller than the flow area of the water inlet of the anti-freeze valve 20, further increasing the flow rate of the drain valve group.

Specifically, the anti-freezing valve 20 further comprises an anti-freezing valve core 25, one end of the temperature bulb 21 is in stop fit with the anti-freezing valve core 25, the anti-freezing valve core 25 is movably arranged in the drainage channel 22, and the temperature bulb 21 opens and closes the drainage outlet 23 through the anti-freezing valve core 25; the intake valve 30 further includes an intake valve spool 32, and the intake valve spool 32 is floatably disposed in the intake chamber 312 to block or open the intake port 311. The bulb 21 is arranged in this way, and the drain outlet 23 is opened and closed by the antifreeze valve core 25, so that the function of the antifreeze valve 20 is realized; the intake valve core 32 is floatably provided in the intake chamber 312, and can close or open the intake port 311, thereby realizing the function of the intake valve 30.

Specifically, the solenoid valve 40 further includes a needle structure 42, the second flow port 413 being openably and closably communicated with the drain passage 22, the needle structure 42 being movably disposed in a direction approaching or separating from the second flow port 413 to block or open the second flow port 413. The valve needle structure 42 is movably disposed in a direction approaching or separating from the second flow port 413, and is capable of blocking or opening the second flow port 413, thereby realizing the function of the solenoid valve 40.

The above description is only of the preferred embodiments of the present utility model and is not intended to limit the present utility model, but various modifications and variations can be made to the present utility model by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims (11)

1. A drainage valve block, comprising:

the connecting seat (10), the said connecting seat (10) has water inlet and outlet channel (11) and circulation channel (12) that communicate each other;

the anti-freezing valve (20) is arranged on the connecting seat (10), the anti-freezing valve (20) comprises a temperature bulb (21), a drain channel (22) and a drain outlet (23), the temperature bulb (21) is movably arranged in the drain channel (22) to open and close the drain outlet (23), the maximum distance between one end of the temperature bulb (21) facing the connecting seat (10) and the central line of the water inlet and outlet channel (11) is L1, L1 is less than or equal to 21mm, and the drain outlet (23) is communicated with the drain channel (22) when the drain outlet (23) is opened;

an intake valve (30) provided on the connection base (10), the intake valve (30) having an openable and closable intake port (311), the intake port (311) communicating with the flow passage (12) when the intake port (311) is opened;

and a solenoid valve (40) provided on the connection base (10), the solenoid valve (40) being used to connect or disconnect the circulation passage (12) and the drainage passage (22).

2. The drain valve group according to claim 1, wherein the frost valve (20) is located below the water inlet/outlet passage (11), and the solenoid valve (40) and the bulb (21) are arranged in a staggered manner in a horizontal direction.

3. The drainage valve group according to claim 2, wherein the electromagnetic valve (40) is horizontally arranged, the electromagnetic valve (40) is provided with a first flow port (411), the first flow port (411) is communicated with the flow channel (12), and the distance between the center line of the water inlet and outlet channel (11) and the center line of the first flow port (411) is L2, wherein L2 is more than or equal to 16mm.

4. The drainage valve group according to claim 2, characterized in that the air inlet valve (30) is located above the water inlet and outlet channel (11), the air inlet valve (30) is vertically arranged, the electromagnetic valve (40) is located below the air inlet valve (30), the air inlet valve (30) and the electromagnetic valve (40) are located on the same side of the center line of the water inlet and outlet channel (11), and the distance between the center line of the air inlet (311) and the center line of the water inlet and outlet channel (11) is L3, wherein L3 is greater than or equal to 14mm.

5. The drain valve group according to claim 1, wherein the anti-freeze valve (20) further comprises an anti-freeze valve seat (24), a sealing groove (241) is arranged on the outer wall of the anti-freeze valve seat (24), the drain valve group further comprises a sealing ring (50), the sealing ring (50) is positioned in the sealing groove (241), the connecting seat (10) comprises a main body (13) and an anti-freeze valve joint (14) connected with the main body (13), the anti-freeze valve joint (14) is arranged below the main body (13), the anti-freeze valve seat (24) is arranged on the anti-freeze valve joint (14), the sealing ring (50) seals the joint of the anti-freeze valve seat (24) and the anti-freeze valve joint (14), and the drain channel (22) is arranged in the anti-freeze valve seat (24).

6. The drain valve group according to claim 5, wherein the antifreeze valve seat (24) comprises a connecting section (242) and a first transition section (243) which are sequentially connected, the diameter of the first transition section (243) is larger than that of the connecting section (242), the sealing groove (241) is arranged on the connecting section (242) and is positioned at the joint of the connecting section (242) and the first transition section (243), and the connecting section (242) is connected with the antifreeze valve joint (14).

7. The drainage valve group according to claim 1, wherein the air inlet valve (30) comprises an air inlet valve seat (31), the air inlet valve seat (31) is provided with an air inlet (311), an air inlet cavity (312) and an air outlet which are sequentially arranged from top to bottom, one end of the air inlet cavity (312) is communicated with the air inlet (311), the other end of the air inlet cavity (312) is communicated with the air outlet, the air outlet is communicated with the water inlet and outlet channel (11) and the upper end of the circulation channel (12), and the center line of the circulation channel (12) and the center line of the air inlet cavity (312) are located on the same axis.

8. The drainage valve set according to claim 6, wherein the electromagnetic valve (40) comprises an electromagnetic valve seat (41), the electromagnetic valve seat (41) is provided with a first circulation port (411), an electromagnetic valve circulation cavity (412) and a second circulation port (413) which are communicated with each other, the electromagnetic valve seat (41) is connected with the connecting seat (10), the first circulation port (411) is vertically arranged, the second circulation port (413) is horizontally arranged, the lower end of the circulation channel (12) is communicated with the first circulation port (411), and the central line of the electromagnetic valve circulation cavity (412) and the central line of the electromagnetic valve seat (41) are located on the same axis.

9. The drain valve group according to claim 8, wherein the drain passage (22) communicates with the solenoid valve flow chamber (412), a flow area of the drain passage (22) is larger than a flow area of the solenoid valve flow chamber (412), and a flow area of the second flow port (413) is smaller than a flow area of the water inlet of the anti-freeze valve (20).

10. The drain valve group according to claim 7, wherein the freeze valve (20) further comprises an antifreezing valve core (25), one end of the bulb (21) is in stop fit with the antifreezing valve core (25), the antifreezing valve core (25) is movably arranged in the drain channel (22), and the bulb (21) opens and closes the drain outlet (23) through the antifreezing valve core (25); the intake valve (30) further comprises an intake valve core (32), and the intake valve core (32) is floatably arranged in the intake cavity (312) to block or open the intake port (311).

11. The drain valve group according to claim 8, wherein the solenoid valve (40) further includes a valve needle structure (42), the second flow port (413) being openably and closably communicated with the drain passage (22), the valve needle structure (42) being movably disposed in a direction approaching or separating from the second flow port (413) to block or open the second flow port (413).