An expansion tank for a dual purpose stove and a dual purpose stove

Abstract

The application discloses an expansion water tank for a dual-purpose stove, which comprises a tank body (81), and the inside of the tank body (81) is provided with a liquid cavity (810b) for containing and supplementing the expansion and contraction amount of circulating water in a circulating loop, and is characterized in that the tank body (81) is provided with a descaling agent supply channel (8130), the inlet of the descaling agent supply channel (8130) is connected with a descaling agent storage box (83), the outlet of the descaling agent supply channel (8130) is communicated with the liquid cavity (810b), and the descaling agent supply channel (8130) is provided with a valve (84) for controlling the opening and closing of the descaling agent supply channel (8130). The application further discloses a dual-purpose stove provided with the expansion water tank. Compared with the prior art, the expansion water tank for the dual-purpose stove is convenient for descaling the circulating water path.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of heating equipment, in particular to an expansion water tank for a dual-purpose stove and a dual-purpose stove. BACKGROUND

[0002] At present, some residences are provided with water heating equipment such as floor heating. In these residences, in addition to domestic water supply, additional water supply is needed for the corresponding water heating equipment for heating. Therefore, ordinary gas water heaters cannot simultaneously supply hot water for domestic water and heating water for water heating equipment, and a dual-purpose stove needs to be provided to simultaneously supply hot water for domestic water and heating water.

[0003] In the existing dual-purpose stove, a three-way valve is used for switching control in the inner circulation and the outer circulation. In the heating mode, the dual-purpose stove is switched to the outer circulation, the heat exchange pipeline is connected with the heating pipeline, and under the action of the circulating pump, the water in the heat exchange pipeline is discharged to the heating pipeline after being heated by the combustion heat exchange device. The hot water flows through each room through the outer circulation, so as to realize heating. In the domestic hot water mode, the dual-purpose stove is switched to the inner circulation, and the heat exchange pipeline itself forms a circulation loop. Under the action of the circulating pump, the hot water is heated through the inner circulation when flowing through the heat exchanger, so as to realize the supply of domestic hot water. At this time, the heat exchange pipeline is not connected with the heating pipeline, the outer circulation is interrupted, the water in the heating pipeline is dead water, and the heating is automatically stopped until the use of domestic hot water is finished. In addition, an expansion water tank is generally arranged in the circulation loop in the dual-purpose stove to accommodate and supplement the expansion and contraction amount of the circulating water in the circulation loop. The specific structure can be referred to the Chinese patent application No. CN201710624991.4 (publication No. CN108061375A) of the applicant, entitled "Dual-purpose stove working system".

[0004] However, in the long-term use of the existing gas dual-purpose stove, scale, algae mud and other impurities are gradually generated in the machine interior and the heating terminal (floor heating pipe or heating sheet). These impurities attached to the inner wall of the pipeline will gradually reduce the water area. When the impurities accumulate to a certain extent, the closed heating water system will cause the water pressure to rapidly rise due to the expansion of hot water during each heating, and the water pressure will rapidly exceed the normal working water pressure range of the dual-purpose stove, so that the machine is passively shut down and pressure relief operation is performed. At this time, if the dual-purpose stove is to be normally operated, a service technician must be dispatched to clean the heating terminal to remove the algae mud, scale and other impurities in the heating system, so as to restore the circulation waterway. This is the only method to deal with this problem on the market at present, and the disadvantage is that:

[0005] (1) The problem is dealt with after it occurs, which is relatively passive. If the dual-purpose stove is not timely relieved, the heating waterway (floor heating pipe, heating sheet, machine, connecting piece) will be damaged more seriously due to excessive pressure;

[0006] (2) need to connect the water pump, the descaling agent into the heating system, cleaning the pipeline operation is complicated, users need to pay a large amount of money. SUMMARY

[0007] The first technical problem to be solved by the present application is to provide a dual-purpose stove expansion tank for conveniently descaling the circulating water circuit.

[0008] The second technical problem to be solved by the present application is to provide a dual-purpose stove expansion tank capable of automatically starting and stopping the descaling function according to the accumulation degree of impurities in the circulating water circuit.

[0009] The third technical problem to be solved by the present application is to provide a dual-purpose stove applying the above-mentioned expansion tank.

[0010] The technical solution adopted by the present application to solve the first technical problem is: a dual-purpose stove expansion tank, comprising a tank body, the inside of the tank body having a liquid cavity for accommodating and supplementing the expansion and contraction amount of circulating water in a circulating loop, characterized in that: the tank body has a descaling agent supply channel, the inlet of the descaling agent supply channel being connected with a descaling agent storage box, the outlet of the descaling agent supply channel being communicated with the liquid cavity, and the descaling agent supply channel being provided with a valve for controlling the opening and closing thereof.

[0011] In order to further solve the second technical problem, the tank body is provided with a flexible diaphragm, which divides the internal space of the tank body into a gas cavity and the liquid cavity, the valve comprises a valve core and a transmission member, the valve core being accommodated in the descaling agent supply channel and being capable of sliding along the axial direction of the descaling agent supply channel, the transmission member being installed on the flexible diaphragm and being connected with the valve core, so that the deformed flexible diaphragm can drive the valve core to move through the transmission member, thereby controlling the opening and closing of the descaling agent supply channel.

[0012] In the initial state, the valve core blocks the descaling agent supply channel.

[0013] In the state where the amount of circulating water in the liquid cavity is higher than the set value, the flexible diaphragm deforms towards the gas cavity side, thereby driving the valve core to move synchronously and unblock the descaling agent supply channel.

[0014] In order to ensure the stability of the valve core and facilitate the control of the opening and closing of the detergent supply channel, a sleeve is arranged on the tank, the interior of the sleeve is formed with the detergent supply channel, the port of the first end of the sleeve is used as the inlet of the detergent supply channel, the second end of the sleeve extends into the liquid cavity and is opposite to the flexible diaphragm, and the through hole in the peripheral wall of the sleeve adjacent to the second end is used as the outlet of the detergent supply channel.

[0015] In the initial state, the valve core is arranged in the interior of the sleeve and is located between the port of the first end of the sleeve and the through hole, so that the detergent supply channel is disconnected.

[0016] In the state that the circulating water in the liquid cavity is higher than the set value, the valve core is located in the interior of the sleeve and is located between the port of the second end of the sleeve and the through hole, so that the detergent supply channel is connected.

[0017] In order to avoid the early action of the detergent in the case of slight fluctuation of water pressure or slight accumulation of impurities, in the initial state, the valve core is located in the middle of the detergent supply channel.

[0018] In order to avoid the leakage of the detergent through the gap between the valve core and the sleeve, the peripheral wall of the valve core is sealed with the inner peripheral wall of the sleeve.

[0019] In order to facilitate the installation of the transmission member, the transmission member comprises

[0020] The mounting piece is clamped at the middle position of the flexible diaphragm; and

[0021] The pull rod extends along the axial direction of the sleeve and is connected with the mounting piece and the valve core at both ends respectively.

[0022] In order to facilitate the processing of the tank and the installation of the flexible diaphragm, the tank comprises the first shell and the second shell arranged oppositely, the flexible diaphragm is clamped between the first shell and the second shell, the gas cavity is surrounded by the flexible diaphragm and the first shell, and the liquid cavity is surrounded by the flexible diaphragm and the second shell.

[0023] In order to facilitate the inflation of the gas cavity and the liquid inlet of the liquid cavity, the top of the tank is provided with the inflation port communicated with the gas cavity, and the bottom of the tank is provided with the liquid inlet communicated with the liquid cavity.

[0024] The technical scheme adopted by the present application to solve the third technical problem is a dual-purpose stove applying the expansion water tank.

[0025] In order to realize the functions of domestic hot water and heating, the dual-purpose stove further comprises

[0026] The combustion heat exchange device comprises a heat exchanger with a heat exchange channel;

[0027] The heat exchanger has hot water channel and cold water channel for heat exchange;

[0028] The heat exchange pipeline comprises a first heat exchange section and a second heat exchange section connected in sequence, the first heat exchange section at least partially passes through the heat exchange channel of the heat exchanger, and the second heat exchange section at least partially passes through the hot water channel of the heat exchanger;

[0029] The heating water inlet pipe and the heating water outlet pipe are respectively connected to two ends of the first heat exchange section and are respectively used for connecting to two ends of an external heating pipeline;

[0030] The domestic water inlet pipe and the domestic water outlet pipe are respectively connected to two ends of the cold water channel of the heat exchanger; and

[0031] The delivery pump is installed on the first heat exchange section;

[0032] The liquid cavity is connected to the heat exchange pipeline or the heating water inlet pipe through a pipeline;

[0033] The second heat exchange section and the heating water outlet pipe are respectively provided with valves, so that the dual-purpose stove has at least two states:

[0034] In the first state, the second heat exchange section is connected, and the heating water outlet pipe is disconnected;

[0035] In the second state, the second heat exchange section is disconnected, and the heating water outlet pipe is connected.

[0036] Compared with the prior art, the advantages of the present application are:

[0037] (1) By arranging a descaling agent supply channel in communication with the liquid cavity on the box body, connecting a descaling agent storage box at the inlet of the descaling agent supply channel, and arranging a valve for controlling the opening and closing of the descaling agent supply channel, when descaling is needed, the valve can be opened to connect the descaling agent supply channel, so that the descaling agent in the descaling agent storage box is automatically released into the liquid cavity through the descaling agent supply channel, and is fused with the circulating water pipeline under the action of circulation, so as to timely remove impurities and clean the pipeline, thereby solving the problems of system blockage and overpressure after long-term use of the dual-purpose stove, and prolonging the service life of the dual-purpose stove;

[0038] (2) A valve is formed by a valve core and a transmission component. The deformable flexible diaphragm can drive the valve core to move through the transmission component, thereby controlling the opening and closing of the descaling agent supply channel. In this way, when impurities accumulate to a certain extent in the dual-purpose boiler system, the liquid cavity needs to accommodate more hot water expansion, and the flexible diaphragm will also generate a larger deformation. The flexible diaphragm will drive the valve core to release the blockage of the descaling agent supply channel, thereby automatically starting the descaling function. After the circulating water completes the descaling and the pipeline is unblocked, the circulating water in the liquid cavity can return to the circulating water circuit. At this time, the flexible diaphragm reduces the deformation amount, restores the blockage of the descaling agent supply channel, and automatically closes the descaling function.

[0039] The above solution cleverly uses the deformation of a flexible diaphragm to open and close the valve. On the one hand, it reduces the need for manual judgment of water blockage and tedious cleaning and maintenance operations, greatly saving labor costs. On the other hand, it does not involve the addition of electrical control components, making it a purely mechanical structure with low cost, high reliability, and good consistency. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the structure of an embodiment of the dual-purpose furnace of the present invention;

[0041] Figure 2 for Figure 1 A schematic diagram of the dual-purpose boiler in its first state (arrows indicate the direction of water flow);

[0042] Figure 3 for Figure 1 A schematic diagram of the dual-purpose boiler in its second state (arrows indicate the direction of water flow);

[0043] Figure 4 for Figure 1 3D exploded view of the expansion tank;

[0044] Figure 5 for Figure 1 Longitudinal sectional view of the expansion tank in its initial state;

[0045] Figure 6 for Figure 5 A longitudinal sectional view of the liquid chamber in the expansion tank when the circulating water volume is higher than the set value. Detailed Implementation

[0046] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0047] like Figures 1 to 6 The image shows a preferred embodiment of the dual-purpose furnace of the present invention. The dual-purpose furnace includes a combustion heat exchange device 1, a heat exchanger 2, a heat exchange pipe 3, a heating water inlet pipe 4a, a heating water outlet pipe 4b, a domestic water inlet pipe 5a, a domestic water outlet pipe 5b, a delivery pump 6, a three-way valve 7, and an expansion tank 8.

[0048] The combustion heat exchange device 1 comprises a heat exchanger 11 having a heat exchange channel, a burner 12 for supplying heat to the heat exchanger 11, and a fan 13 for supplying air to the burner 12 and discharging flue gas.

[0049] The heat exchanger 2 has a hot water channel and a cold water channel inside, which exchange heat with each other.

[0050] The heat exchange pipeline 3 is a circulating pipeline, comprising a first heat exchange section 31 and a second heat exchange section 32 connected in sequence. Specifically, the first heat exchange section 31 partially passes through the heat exchange channel of the heat exchanger 13, and the second heat exchange section 32 partially passes through the hot water channel of the heat exchanger 2.

[0051] The heating water inlet pipe 4a and the heating water outlet pipe 4b are respectively connected to the inlet end and the outlet end of the first heat exchange section 31, and are respectively used for connecting to the two ends of the external heating pipeline.

[0052] The living water inlet pipe 5a and the living water outlet pipe 5b are respectively connected to the two ends of the cold water channel of the heat exchanger 2.

[0053] The delivery pump 6 is installed on the first heat exchange section 31, and can deliver water flow from the inlet end of the first heat exchange section 31 to the outlet end of the first heat exchange section 31.

[0054] The three-way valve 7 has a water inlet end, a first water outlet end and a second water outlet end. The water inlet end of the three-way valve 7 is communicated with the outlet end of the first heat exchange section 31, the first water outlet end of the three-way valve 7 is communicated with the inlet end of the second heat exchange section 32, and the second water outlet end of the three-way valve 7 is communicated with the heating water outlet pipe 4b. By adjusting the three-way valve 7, the communication and disconnection of the second heat exchange section 32 and the heating water outlet pipe 4b can be controlled.

[0055] By adjusting the three-way valve 7, the dual-purpose stove has at least two states:

[0056] In the first state, as shown in Figure 2 , the second heat exchange section 32 is communicated, and the heating water outlet pipe 4b is disconnected, so that the heat exchange pipeline 3 alone forms a circulating loop, which is called internal circulation in the background art;

[0057] In the second state, as shown in Figure 3 , the second heat exchange section 32 is disconnected, and the heating water outlet pipe 4b is communicated, so that the heating water inlet pipe 4a, the first heat exchange section 31, the heating water outlet pipe 4b and the external heating pipeline together form a circulating loop, which is called external circulation in the background art.

[0058] The expansion tank 8 comprises a tank body 81, a flexible diaphragm 82, a descaling agent storage box 83 and a valve 84.

[0059] Specifically, the box 81 comprises a first shell 811 and a second shell 812 arranged oppositely.

[0060] The flexible diaphragm 82 is arranged substantially vertically and clamped between the first shell 811 and the second shell 812, and a gas cavity 810a is formed between the flexible diaphragm 82 and the first shell 811, and a liquid cavity 810b is formed between the flexible diaphragm 82 and the second shell 812.

[0061] In the embodiment, the top of the first shell 811 is provided with a gas inlet 8111 communicating with the gas cavity 810a, and the bottom of the second shell 812 is provided with a liquid inlet 8121 communicating with the liquid cavity 810b, and the liquid inlet 8121 is communicated with the first heat exchange section 31 through a pipeline, so that the liquid cavity 810b can accommodate and supplement the expansion and contraction amount of the circulating water in the circulating loop; the side of the second shell 812 is provided with a sleeve 813 arranged substantially horizontally, and the inside of the sleeve 813 is formed with a descaling agent supply channel 8130, and the port of the first end of the sleeve 813 serves as the inlet of the descaling agent supply channel 8130, and the second end of the sleeve 813 extends into the liquid cavity 810b and is opposite to the flexible diaphragm 82, and the peripheral wall adjacent to the second end of the sleeve 813 is provided with a flow-through hole 8131 communicating with the liquid cavity 810b as the outlet of the descaling agent supply channel 8130.

[0062] The descaling agent storage box 83 is installed outside the box 81 and connected at the inlet of the descaling agent supply channel 8130.

[0063] The valve 84 is arranged at the descaling agent supply channel 8130 and comprises a valve core 841 and a transmission member 842. Specifically, the valve core 841 is accommodated in the descaling agent supply channel 8130 and can slide along the axial direction of the descaling agent supply channel 8130, and the peripheral wall of the valve core 841 is sealingly matched with the inner peripheral wall of the sleeve 813 through a sealing ring 8411; the transmission member 842 comprises a mounting plate 8421 and a pull rod 8422, the mounting plate 8421 is clamped at the middle position of the flexible diaphragm 82, and the pull rod 8422 extends along the axial direction of the sleeve 813, and the two ends of the pull rod 8422 are connected with the mounting plate 8421 and the valve core 841 respectively, so that the deformed flexible diaphragm 82 can drive the valve core 841 to move through the transmission member 842, thereby controlling the opening and closing of the descaling agent supply channel 8130.

[0064] In the initial state, as shown in Figure 5 , the valve core 841 is accommodated in the sleeve 813 at a position between the port of the first end of the sleeve 813 and the flow-through hole 8131, and blocks the middle part of the descaling agent supply channel 8130, so that the descaling agent supply channel 8130 is disconnected;

[0065] In the state that the amount of circulating water in the liquid cavity 810b is higher than the set value, as shown in Figure 6As shown, the flexible diaphragm 82 deforms toward the gas cavity 810a, thereby driving the valve core 841 to move synchronously to the position inside the sleeve 813 between the port at the second end of the sleeve 813 and the flow hole 8131, thereby releasing the blockage of the descaling agent supply channel 8130 and making the descaling agent supply channel 8130 open.

[0066] The above-mentioned dual-purpose furnace has two operating modes:

[0067] In domestic hot water mode, the dual-purpose boiler is switched to hot water mode via the three-way valve 7. Figure 2 In the first state shown, the second heat exchange section 32 is connected and the heating outlet pipe 4b is disconnected, so that the heat exchange pipe 3 forms a separate circulation loop. Under the action of the delivery pump 6, the water in the first heat exchange section 31 of the heat exchange pipe 3 is heated by the combustion heat exchange device 1 and then enters the second heat exchange section 32. When the hot water in the second heat exchange section 32 passes through the heat exchanger 2, it exchanges heat with the cold water introduced by the domestic water inlet pipe 5a. After the cold water is heated into hot water, it is supplied to the user through the domestic water outlet pipe 5b. The water in the second heat exchange section 32 finally returns to the first heat exchange section 31 to replenish the heat, thereby realizing the continuous supply of domestic hot water.

[0068] In heating mode, the dual-purpose boiler is switched to the following mode via the three-way valve 7: Figure 3 In the second state shown, the second heat exchange section 32 is disconnected, and the heating outlet pipe 4b is connected, so that the heating inlet pipe 4a, the first heat exchange section 31, the heating outlet pipe 4b and the external heating pipeline together form a circulation loop. Under the action of the delivery pump 6, the water in the first heat exchange section 31 of the heat exchange pipe 3 is heated by the combustion heat exchange device 1 and discharged to the heating outlet pipe 4b. The hot water flows through each room to dissipate heat through the external heating pipeline, and finally returns to the first heat exchange section 31 through the heating inlet pipe 4a to replenish the heat, thereby achieving continuous heating for each room.

[0069] The working principle of this embodiment is as follows:

[0070] (1) In the initial state, the gas cavity 810a will be pre-filled with a gas pressure of about 1.5 bar to make the pressure on both sides of the flexible diaphragm 82 equal, such as Figure 5 As shown, at this time, the valve core 841 is housed inside the sleeve 813 at the position between the port at the first end of the sleeve 813 and the flow hole 8131, blocking the middle of the descaling agent supply channel 8130, so as to disconnect the descaling agent supply channel 8130.

[0071] (2) When the dual-purpose stove is working, the liquid cavity 810b of the expansion tank 8 can accommodate and supplement the expansion and contraction of the circulating water in the circulating loop to ensure the stability of the pressure of the dual-purpose stove system. The amount of circulating water in the liquid cavity 810b will increase or decrease, so that the flexible diaphragm 82 deforms and the valve core 841 moves synchronously. Since the valve core 841 is located in the middle of the detergent supply channel 8130 in the initial state, when the amount of circulating water changes slightly, the valve core 841 will move near the middle of the detergent supply channel 8130, and the detergent supply channel 8130 will always be blocked.

[0072] When the amount of impurities accumulated in the dual-purpose stove system is slight, the deformation amount of the flexible diaphragm 82 is small (the deformation amount of the flexible diaphragm 82 indirectly reflects the degree of accumulation of impurities in the circulating water circuit), and the blockage of the detergent supply channel 8130 cannot be removed. This can prevent the detergent from working too early.

[0073] When the amount of impurities accumulated in the dual-purpose stove system reaches a certain degree, the liquid cavity 810b needs to accommodate more hot water expansion, and the flexible diaphragm 82 will also produce a larger deformation amount, as shown in Figure 6 When the amount of circulating water in the liquid cavity 810b is higher than the set value, the flexible diaphragm 82 moves the valve core 841 synchronously to a position between the port at the second end of the sleeve 813 and the flow-through hole 8131 inside the sleeve 813, unblocks the detergent supply channel 8130, and makes the detergent supply channel 8130 communicate. In this way, the detergent in the detergent storage box 83 will be automatically released into the liquid cavity 810b through the detergent supply channel 8130, and will be mixed with the circulating water under the action of circulation to timely remove impurities and keep the pipeline clean, effectively avoiding the problem of overpressure in the water circuit.

[0074] After the circulating water completes the descaling and the pipeline is unblocked, the circulating water in the liquid cavity 810b can return to the circulating water circuit. At this time, the flexible diaphragm 82 reduces the deformation amount and restores the blockage of the detergent supply channel 8130, preventing the continuous release of the detergent into the circulating water and avoiding the waste of the detergent.

[0075] Through the above reciprocating action, the dual-purpose stove system realizes complete autonomous self-cleaning and descaling.

[0076] The advantages of the above scheme are:

[0077] ① The problem of system blockage and overpressure after long-term use of the dual-purpose stove is solved, and the service life is prolonged;

[0078] ② The above self-cleaning and descaling method reduces the manual judgment of water blockage and the tedious cleaning and maintenance operation, greatly saving labor costs;

[0079] 3. The above scheme does not involve the increase of electric control elements, and is a pure mechanical structure, low in cost, high in reliability and good in consistency.

Claims

1. An expansion tank for a dual-purpose boiler, comprising a tank body (81) having an interior liquid cavity (810b) for accommodating and replenishing the expansion and contraction of circulating water in a circulation loop, characterized in that: The housing (81) has a descaling agent supply channel (8130), the inlet of which is connected to a descaling agent storage box (83), and the outlet of which is connected to the liquid cavity (810b). A valve (84) for controlling the opening and closing of the descaling agent supply channel (8130) is provided at the descaling agent supply channel (8130). The housing (81) is provided with a flexible diaphragm (82), which divides the internal space of the housing (81) into a gas chamber (810a) and a liquid chamber (810b). The valve (84) includes a valve core (841) and a transmission component (842). The valve core (841) is housed in the descaling agent supply channel (8130) and can slide along the axial direction of the descaling agent supply channel (8130). The transmission component (842) is installed on the flexible diaphragm (82) and connected to the valve core (841) so that the deformable flexible diaphragm (82) can drive the valve core (841) to move through the transmission component (842), thereby controlling the opening and closing of the descaling agent supply channel (8130). In the initial state, the valve core (841) blocks the descaling agent supply channel (8130); When the circulating water volume in the liquid cavity (810b) is higher than the set value, the flexible diaphragm (82) deforms toward the gas cavity (810a), thereby driving the valve core (841) to move synchronously to release the blockage of the descaling agent supply channel (8130).

2. The expansion tank according to claim 1, characterized in that: The housing (81) is provided with a sleeve (813), and the inside of the sleeve (813) forms the descaling agent supply channel (8130). The port at the first end of the sleeve (813) serves as the inlet of the descaling agent supply channel (8130). The second end of the sleeve (813) extends into the liquid cavity (810b) and faces the flexible diaphragm (82). A flow hole (8131) is provided on the peripheral wall of the sleeve (813) near the second end as the outlet of the descaling agent supply channel (8130). In the initial state, the valve core (841) is housed inside the sleeve (813) at a position between the port at the first end of the sleeve (813) and the flow hole (8131) to disconnect the descaling agent supply channel (8130); When the circulating water volume in the liquid cavity (810b) is higher than the set value, the valve core (841) is located inside the sleeve (813) between the port at the second end of the sleeve (813) and the flow hole (8131) to connect the descaling agent supply channel (8130).

3. The expansion tank according to claim 2, characterized in that: In the initial state, the valve core (841) is located in the middle of the descaling agent supply channel (8130).

4. The expansion tank according to claim 2, characterized in that: The outer peripheral wall of the valve core (841) is sealed to the inner peripheral wall of the sleeve (813) by a sealing ring (8411).

5. The expansion tank according to claim 2, characterized in that: The transmission component (842) includes: The mounting piece (8421) is engaged in the middle position of the flexible diaphragm (82); and A pull rod (8422) extends axially along the sleeve (813) and its two ends are connected to the mounting plate (8421) and the valve core (841) respectively.

6. The expansion tank according to any one of claims 1 to 5, characterized in that: The housing (81) includes a first shell (811) and a second shell (812) arranged opposite to each other. The flexible diaphragm (82) is sandwiched between the first shell (811) and the second shell (812). The flexible diaphragm (82) and the first shell (811) surround and form the gas cavity (810a), and the flexible diaphragm (82) and the second shell (812) surround and form the liquid cavity (810b).

7. The expansion tank according to any one of claims 1 to 5, characterized in that: The top of the box (81) is provided with an air inlet (8111) that communicates with the gas chamber (810a), and the bottom of the box (81) is provided with a liquid inlet (8121) that communicates with the liquid chamber (810b).

8. A dual-purpose boiler employing an expansion tank as described in any one of claims 1 to 7.

9. The dual-purpose furnace according to claim 8, characterized in that: It also includes Combustion heat exchange device (1), including a heat exchanger (11) with heat exchange channels; The heat exchanger (2) has a hot water channel and a cold water channel that exchange heat with each other. The heat exchange pipe (3) includes a first heat exchange section (31) and a second heat exchange section (32) connected in sequence. The first heat exchange section (31) passes through the heat exchange channel of the heat exchanger (11) in at least part, and the second heat exchange section (32) passes through the hot water channel of the heat exchanger (2) in at least part. The heating inlet pipe (4a) and the heating outlet pipe (4b) are respectively connected to the two ends of the first heat exchange section (31) and are respectively used to connect to the two ends of the external heating pipeline. A domestic water inlet pipe (5a) and a domestic water outlet pipe (5b) are respectively connected to both ends of the cold water passage of the heat exchanger (2); and A transfer pump (6) is installed on the first heat exchange section (31); The liquid cavity (810b) is connected to the heat exchange pipe (3) or the heating water inlet pipe (4a) through a pipeline; Valves are provided on the second heat exchange section (32) and the heating outlet pipe (4b) to ensure that the dual-purpose boiler has at least two states: In the first state, the second heat exchange section (32) is connected, and the heating outlet pipe (4b) is disconnected; In the second state, the second heat exchange section (32) is disconnected, and the heating outlet pipe (4b) is connected.

Images