JP2010025379A - Water heater and hot water supply system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hot water supply system capable of surely discharging counterflowing hot water and mixed water to the external. <P>SOLUTION: The hot water supply system 100 supplies the mixed water of desired temperature by mixing clean water and hot water, and includes, for example, a hot water storage section 10, a hot water supply pipe 11, a water supply 20, a clean water supply pipe 21, and a water heater 30. The water heater 30 includes at least a hot water pipe conduit 31, a clean water pipe conduit 32, a mixing section 33, a counterflowing water discharge section 34 and a mixed water supply pipe 39. The hot water pipe conduit 31 and the clean water pipe conduit 32 are respectively connected with the hot water supply pipe 11 and the clean water supply pipe 21. The hot water and the clean water respectively pass through the hot water pipe conduit 31 and the clean water pipe conduit 32 and mixed at the mixing section 33 to produce the mixed water. The counterflowing water discharge section 34 surely discharges the counterflowing hot water or mixed water to the external at a draining section 341 even when the hot water or mixed water counterflows to the clean water pipe conduit 32 from the mixing section 33. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a water heater and a hot water supply system that mix water and hot water to supply mixed water at a desired temperature, and in particular, a water heater that does not allow hot water or mixed water to flow back into a water supply that is a supply source of water. , And a hot water supply system.

  Conventionally, from the viewpoint of energy saving, there has been a hot water supply system using a solar water heater that generates hot water by heating solar water stored in a tank. Among them, in a hot water supply system that connects a natural circulation solar water heater and a water heater that are cut off from the water supply, it is necessary to take measures against cross connection with the water supply that is prohibited by the Water Supply Law.

  As a countermeasure, a system has been devised in which only the water supply pipe from the natural circulation solar water heater is connected to the water supply connection port of the water heater. However, in that system, when hot water is supplied from the natural circulation solar water heater through the water supply pipe to the hot water heater, there is no means for mixing with cold water in the hot water heater, so the temperature of the hot water supplied from the hot water heater Control was not possible. For this reason, in the hot water supply system, it has been impossible to supply low-temperature hot water or automatically supply hot water having a desired temperature to the bath tub.

  As a solution to the above problems, the following bath hot water system has been proposed. The bath water supply system includes a solar water heater, a water supply, a bath water heater, a water pipe connecting the water supply and the bath water heater, a circulation pipe connecting the bathtub, the bathtub and the bath water heater, and a solar water heater. Hot water is discharged, a hot water pipe connected to the circulation pipe, and a hot water solar water heater compatible box that detects and controls information of hot water discharged from the solar water heater (see, for example, Patent Document 1). .)

According to this bath water heater system, the temperature of the hot water from the solar water heater detected in the hot water solar water heater compatible box, the temperature of the water from the water supply detected in the bath water heater, Based on the set temperature and the set amount of hot water set for the control unit, calculation processing is performed in the control unit in the bath water heater, and the amount of hot water and clean water corresponding to the result is supplied to the bathtub through the circulation pipe. Is done. And the vacuum breaker with a non-return valve which has the function which interrupts | blocks the backflow from a downstream to an upstream is provided in the bath water heater, and the hot water in a solar water heater is prevented from flowing back into a water supply.
JP-A-10-205893 (FIGS. 1 and 2)

  However, in the bath hot water system described above, only the vacuum breaker with a check valve prevents hot water from flowing back into the water heater into the water supply, so if there is something wrong with the vacuum breaker with a check valve, There is a possibility that the hot water in the water heater flows backward toward the water supply. If the hot water in the solar water heater flows backward toward the water supply, the water supply will be contaminated.

  Then, an object of this invention is to provide the hot water supply device and hot water supply system which discharge | emit the warm water and mixed water which have flowed back reliably outside.

  The present invention has been made to solve the above-described problems, and a hot water supply system according to the present invention includes a water supply pipe for supplying water from a water supply, hot water storage means for storing hot water, and the hot water storage water. A hot water supply pipe for supplying hot water stored in the means, clean water supplied from the hot water supply pipe, and hot water supplied from the hot water supply pipe are mixed to produce mixed water at a desired temperature. The hot water supply device supplies the hot water or the mixed water that has flowed back when the hot water or the mixed water supplied from the hot water supply tube flows backward toward the upper water supply tube. It is characterized by comprising a backflow water drainage means for draining. Thereby, the effect | action which drains the warm water and mixed water which flowed back reliably outside is brought about.

  Further, the water heater of the present invention includes a water supply pipe that is a passage of water supplied from a water supply, a hot water pipe that is a passage of hot water supplied from hot water storage means for storing hot water, and the above water supply pipe And a mixing means connected to the hot water pipe, mixing the clean water and warm water to generate mixed water of a desired temperature and supplying it downstream, and provided on the clean water pipe side, and to the clean water pipe And a backflow water draining means for draining the backflowed warm water or mixed water to the outside when the warm water or the mixed water flows back. Thereby, the effect | action which drains the warm water and mixed water which flowed back reliably outside is brought about.

  Further, in the water heater of the present invention, the backflow water draining means has a drainage port, and opens and closes the drainage port according to the magnitude of the water supply pressure from the water supply and the pressure in the water supply pipe. Drainage means, a supply water pressure supply means for supplying the drainage means with a pressure in the vicinity of the entrance, which is a predetermined area near the entrance of the clean water in the water supply pipe, as a feed water pressure from the water supply, and a region near the entrance And a water supply pressure supply means for supplying the drainage means with a pressure in a predetermined region in the water supply pipe located downstream as a pressure in the water supply pipe. This brings about the effect | action that a drain outlet is opened and closed according to the magnitude | size of the water supply pressure from a water supply, and the magnitude | size of the pressure in the said water supply pipe line.

  In the water heater of the present invention, the drain means opens the drain port when the magnitude of the feed water pressure is less than or equal to a predetermined pressure, and the magnitude of the feed water pressure is greater than or equal to the magnitude of the predetermined pressure. In this case, when the magnitude of the water supply pressure is larger than the magnitude of the pressure in the water supply pipe, the drain outlet is closed, and when the magnitude of the water supply pressure is smaller than the magnitude of the pressure in the water supply pipe, It is characterized by opening the drain. Thus, depending on the magnitude of the feed water pressure, the drain outlet is closed when the magnitude of the feed water pressure from the water supply is greater than the magnitude of the pressure in the water supply pipe, and the magnitude of the feed water pressure is within the water feed pipe. When the pressure is smaller than the pressure, the drainage port is opened.

  Further, in the water heater of the present invention, the water supply pressure supply means is a first check valve for preventing a reverse flow from the downstream to the upstream of the water supply pipe provided near the inlet of the water in the water supply pipe. A second check valve for preventing a reverse flow from the downstream to the upstream of the upper water pipe provided in the upper water pipe downstream of the first check valve, and the first check A first connecting pipe that connects the drain pipe and the water supply line between the valve and the second check valve, and includes the first check valve and the second check valve. The pressure in the water supply pipe in the meantime is supplied to the drainage means through the first connecting pipe as the water supply pressure from the water supply. This brings about the effect | action that the pressure in the water supply pipe line between a 1st non-return valve and a 2nd non-return valve is given to a drainage means as feed water pressure. Further, the first check valve and the second check valve can strengthen the backflow prevention function in the water supply pipe line.

  Further, in the water heater according to the present invention, the pressure supply means in the water supply line includes the second check valve and the upper water pipe provided in the water supply line downstream of the second check valve. A third check valve for preventing a reverse flow from downstream to upstream of the water pipe, and the upper water pipe and the drainage means between the second check valve and the third check valve are connected to each other. A second connecting pipe, and the pressure in the upper water pipe between the second check valve and the third check valve is used as the pressure in the upper water pipe. It is given to the said drainage means through. This brings about the effect | action that the pressure in the water supply line between the 2nd check valve and the 3rd check valve is given to the drainage means as the pressure in the water supply line. The second check valve and the third check valve can strengthen the backflow prevention function in the water supply line.

  Moreover, the water heater of the present invention is characterized in that a pressure reducing valve is further provided in the water supply line between the first check valve and the second check valve. As a result, there is an effect of causing a pressure difference between the feed water pressure and the pressure in the water supply pipe.

  Further, the hot water storage means for storing hot water supplied to the water heater of the present invention is connected to the water supply and is cut off from the water supply. Even if the hot water storage means is connected to the water heater, there is an effect that a problem in the water supply law does not occur.

  According to the present invention, it is possible to achieve an excellent effect that the warm water and the mixed water that have flowed back can be reliably discharged to the outside.

  Next, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a diagram showing a hot water supply system 100 according to an embodiment of the present invention. The hot water supply system 100 mixes clean water and warm water and supplies mixed water having a desired temperature. For example, the warm water storage unit 10, the warm water supply pipe 11, the tap water 20, and the clean water supply pipe 21 are provided. And a water heater 30. In the present invention, mixed water refers to water produced as a result of mixing clean water and warm water.

  The warm water reservoir 10 stores warm water. As the hot water storage unit 10, for example, a solar water heater that is supplied from the water supply 20 through the water supply pipe 24 and stored in the tank to make the hot water warm by solar heat is not limited thereto. In other words, the hot water storage unit 10 includes not only solar heat but also those having a function of generating hot water by heating water containing clean water other than that. The warm water stored in the warm water reservoir 10 is supplied to the hot water heater 30 through the warm water supply pipe 11 connected to the bottom of the warm water reservoir 10. Further, the clean water in the water supply 20 is supplied to the hot water heater 30 through the clean water supply pipe 21. Further, the tap water in the tap water 20 can be supplied to others through the tap water supply pipe 23 by opening the branch water supply valves 22a to 22d. As the branch water supply valves 22a to 22d, for example, a water supply valve in an outdoor water supply, a water supply valve in an indoor shower, a water supply valve in a bathroom or a kitchen, and the like are assumed, but not limited thereto.

  The water heater 30 mixes clean water and warm water and supplies mixed water having a desired temperature to the outside. For example, the warm water conduit 31, the clean water conduit 32, the mixing unit 33, and the backflow water A drainage section 34, mixed water pipes 35a and 35b, a heat exchanger 36, a heating water pipe 37, a mixing section 38, and a mixed water supply pipe 39 are provided.

  The hot water pipe 31 is a passage of hot water supplied from the hot water reservoir 10 through the hot water supply pipe 11, and one end thereof is connected to the hot water supply pipe 11. Further, the hot water pipe 31 is connected to the mixing unit 33 at the other end, and hot water passing through the hot water pipe 31 is supplied to the mixing unit 33.

  The water supply pipe 32 is a passage of water supplied from the water supply 20 through the water supply pipe 21, and one end thereof is connected to the water supply pipe 21. The upper water pipe 32 is connected to the mixing unit 33 at the other end, and the upper water passing through the upper water pipe 32 is supplied to the mixing unit 33.

  The mixing unit 33 mixes the warm water supplied from the hot water pipe 31 and the clean water supplied from the clean water pipe 32 to generate mixed water having a desired temperature, and the mixed water is mixed with the mixed water pipe 35a and It is supplied further downstream through 35b. For example, the mixing unit 33 is assumed to be configured by a temperature sensor (not shown) and a mixing valve (not shown), but is not limited thereto.

  When the mixing unit 33 includes a temperature sensor and a mixing valve, for example, based on the temperature of hot water and the temperature of hot water detected by the temperature sensor, and a preset temperature, the mixing valve is connected to the water and hot water. Is mixed at an appropriate ratio to generate mixed water having a preset temperature. Then, the mixed water is supplied further downstream through the mixed water pipes 35a and 35b.

  The backflow water drainage unit 34 drains the backflowed hot water or mixed water to the outside when the hot water or the mixed water flows back to the water supply pipe 32. For example, the drainage unit 341, the feed water pressure supply unit 342, And a water supply pressure supply part 343.

  The drainage unit 341 has a drainage port (not shown), and opens or closes the drainage port according to the magnitude of the water supply pressure from the water supply 20 and the pressure in the water supply pipe 32, or warm water or mixed water. Is drained from the drain outlet. An example of the structure of the drainage section 341 will be described with reference to FIG.

  The water supply pressure supply unit 342 gives the drainage unit 341 with the pressure P1 in the vicinity of the entrance A, which is a predetermined region near the entrance of the clean water in the clean water pipe 32, as the supply water pressure from the water supply 20. The feed water pressure supply unit 342 is connected to the drainage unit 341 by the water supply pipe 32a, and applies the pressure P1 to the drainage unit 341 through the water supply pipe 32a. By opening any of the branch water supply valves 22a to 22d, even if the water supply pressure from the water supply 20 to the water heater 30 is suddenly lowered, the water supply pressure provided to the drainage unit 341 is provided by providing the water supply pressure supply unit 342. The impact can be reduced.

  The water supply line pressure supply unit 343 applies the pressure P2 in the predetermined region B in the water supply conduit 32 located downstream of the entrance vicinity region A to the drainage unit 341 as the pressure in the water supply conduit 32. . The water supply line pressure supply unit 343 is connected to the drainage unit 341 by the water supply channel 32b, and applies pressure P2 to the drainage unit 341 through the water supply channel 32b.

  Therefore, the drainage part 341 opens and closes the drainage port according to the magnitude of the pressure P1 in the area A near the entrance and the magnitude of the pressure P2 in the predetermined area B. For example, when the pressure P1 is smaller than the predetermined pressure P ′ (P ′> P1), the drain port is opened and the pressure P1 is equal to the predetermined pressure. When it is larger than P ′ (P ′ ≦ P1), when the pressure P1 is larger than the pressure P2 (P1 ≧ P2), the drain is closed and the pressure P1 is the pressure. When the size is equal to or smaller than the size of P2 (P1 <P2), a mode in which the drainage port is opened is assumed, but this is not restrictive.

  If the backflow water drainage section 34 is configured as described above, the hot water or the mixed water flows backward from the mixing section 33 toward the upstream of the water supply pipe 32, and even if P1 <P2, the backflowing hot water or Since the mixed water is drained in the drainage section 341, the warm water or the mixed water does not flow back to the water supply 20.

  In particular, when hot water stored in the hot water storage section 10 is stored in such a manner that it is treated as sewage under the Waterworks Law, supply of clean water from the water supply and the connection port that receives the supply of warm water as in the water heater 30 When the connection port to receive is provided in the water heater, there is a possibility that the hot water flows backward to the water supply side and the hot water flows into the water supply 20. If the water heater provided with the connection port that receives the supply of hot water and the connection port that receives the supply of clean water from the water supply 20 is configured as the water heater 30 described above, the hot water that has flowed back to the clean water side can be reliably Because it can be drained, it does not cause any problems in the water law.

  The heat exchanger 36 heats the mixed water supplied through the mixed water pipe 35b to generate mixed water at a predetermined temperature. The mixed water heated by the heat exchanger 36 is supplied to the mixing unit 38 through the heating water pipe 37.

  The mixing unit 38 has the same function as the mixing unit 33 described above. That is, the mixed water supplied from the mixed water pipe 35 a and the mixed water supplied from the heating water pipe 37 are mixed to generate mixed water at a desired temperature, and the branched water supply valves 22 a to 22 a through the mixed water supply pipe 39 are generated. The mixed water is supplied to 22d. The mixing unit 38 is assumed to be configured with, for example, a temperature sensor (not shown) and a mixing valve (not shown) like the mixing unit 33, but is not limited thereto. Since the operation of the temperature sensor and the mixing valve has been described above, the description thereof is omitted here. By appropriately operating the branch water supply valves 22a to 22d, mixed water having a desired temperature is supplied to the outside.

  When the temperature of the warm water in the warm water storage unit 10 is low, there is a possibility that mixed water having a desired temperature cannot be generated even if the mixing unit 33 mixes clean water and warm water. For this reason, the water heater 30 is provided with a heat exchanger 36 and a mixing unit 38.

  In the description of the water heater 30, for example, a member for preventing a back flow from downstream to upstream such as a check valve is not mentioned, but in addition to the above configuration, a back flow from downstream to upstream of the check valve or the like is prevented. Naturally, it is within the scope of the present invention to appropriately arrange the members to be placed in the water heater 30.

  FIG. 2 is a diagram showing a drain valve 400 that is an example of the drain section 341 in the hot water supply system 100 according to the embodiment of the present invention. The drain valve 400 includes a water supply pressure receiving part 410, a water pipe pressure receiving part 420, a drain outlet 430, and a drain outlet opening / closing control part 440.

  The feed water pressure receiving unit 410 receives the pressure P1 as the feed water pressure from the feed water pressure providing unit 342. The water supply pressure receiving portion 410 is constituted by, for example, a tubular member 411 and is connected to the water supply pipe 32 a at an opening 412 at an end of the tubular member 411. Further, the other end of the tubular member 411 is in contact with a diaphragm 443 described later, and the diaphragm 443 closes the other end of the tubular member 411. The space formed by the tubular member 411 and the diaphragm 443 receives the pressure P1.

  The upper water pipe pressure receiving part 420 receives the pressure P2 in the upper water pipe 32 from the upper water pipe pressure supply part 343. The pressure receiving part 420 in the upper water pipe is constituted by, for example, a tubular member 421 and is connected to the upper water pipe 32b at the opening 422 at the end of the tubular member 421.

  The drainage port 430 is a drainage port for draining warm water or mixed water that has flowed back to the water supply pipe 32. Warm water or mixed water that has flowed back to the water pipe 32 is guided to the pressure receiver 420 in the water pipe through the water pipe 32b. Then, when the drain opening / closing control unit 440 described later communicates the drain port 430 and the pressure receiving unit 420 in the upper water pipe, the hot water or the mixed water guided to the pressure receiving unit 420 in the upper water pipe Drained from 430 to the outside.

  The drain port opening / closing control unit 440 controls communication between the pressure receiving unit 420 in the water pipe and the drain port 430, and includes a piston 441, a valve body 442, a diaphragm 443, and a spring member 444. The piston 441 is arranged so as to be able to move in the direction of arrow C (the axial direction of the tubular member 421). The annular valve body 442 is attached by being fitted into the piston 441.

  The diaphragm 443 is attached to the end portion of the piston 441 by fitting the concave portion of the diaphragm 443 to the convex portion provided at the end portion of the piston 441. End portions 443a and 443b of the diaphragm 443 are sandwiched between the water supply pressure receiving portion 410 and the drainage port 430, and the water supply pressure receiving portion 410 and the water supply line pressure receiving portion 420, respectively. One end of the spring member 444 is attached to the end of the piston 441, and the other end is attached to a predetermined position inside the tubular member 421.

  Next, the operation of the drain valve 400 will be described. When the tap water is supplied from the tap water 20 to the tap water pipe 32, the tap water is supplied from the tap water pipe 32a to the feed water pressure receiving portion 410. Here, when the magnitude of the pressure P1 received by the feed water pressure receiving part 410 is not more than the predetermined pressure P ′ (P ′> P1), the magnitude of the pressure P2 applied to the pressure receiving part 420 in the water supply line Regardless, the force with which the spring member 444 pushes the piston 441 in the direction of the arrow D overcomes the pressure P1. For this reason, piston 441 moves in the direction of arrow D, and valve body 442 also moves in the direction of arrow D accordingly. When the valve body 442 moves in the direction of arrow D, a passage is formed between the valve body 442 and the inner wall of the drain port 430. Thereby, the drain outlet 430 and the pressure receiving part 420 in the water supply pipe line are in communication with each other. That is, the drainage port 430 is opened.

  The predetermined pressure P ′ is determined by the elastic force in the spring member 444 and the pressure receiving area of the diaphragm 443. In the following, when the magnitude of the pressure P1 and the magnitude of the pressure P2 are the same, the valve body 442 and the inner wall of the drain port 430 are brought into contact with each other so that the valve body 442 and the inner wall of the drain port 430 are in contact with each other. It is assumed that the elastic force of the spring member 444 and the pressure receiving area of the diaphragm 443 are set so that the passage between them is blocked (so that the drain port 430 is closed).

  When the magnitude of the pressure P1 received by the feed water pressure receiving portion 410 is greater than or equal to the magnitude of the predetermined pressure P ′ (P ′ ≦ P1), the drain valve 400 operates as follows. When clean water flows from upstream to downstream in the water heater 30 in the clean water pipe 32, it can be said that the pressure P1 is larger than the pressure P2 (P1 ≧ P2). In this case, the piston 441 is moved in a direction toward the pressure receiver 420 in the upper water pipe of the arrow C. When the piston 441 moves in the direction toward the upper water pipe pressure receiving part 420 of the arrow C, the valve body 442 attached to the piston 441 comes into contact with the inner wall of the drainage port 430 and drains the upper water pipe pressure receiving part 420 and the drainage. The passage with the mouth 430 is closed. Thereby, the drain outlet 430 will be in the closed state.

  On the other hand, when a negative pressure is generated in the water supply pipe 32 and the hot water or the mixed water flows backward, it can be said that the pressure P1 is equal to or smaller than the pressure P2 (P1 <P2). . In this case, first, the diaphragm 443 senses a decrease in the pressure P 1, and the diaphragm 443 is pulled in the direction of the arrow D and comes into contact with the inner wall of the tubular member 421. Accordingly, the piston 441 is moved in a direction away from the pressure receiving portion 420 in the upper water pipe of the arrow C by the urging force of the spring member 444. When the piston 441 moves in a direction away from the pressure receiving portion 420 in the upper water pipe of the arrow C, the valve body 442 moves away from the inner wall of the drain port 430. As a result, a passage is formed between the valve body 442 and the inner wall of the drain port 430, and the drain port 430 and the pressure receiving part 420 in the upper water pipe line are in communication with each other. That is, the drainage port 430 is opened. Then, warm water, mixed water, or the like that has flowed from the pressure receiving portion 420 in the upper water pipe is flowed to the outside from the drain port 430.

  FIG. 3 is a diagram illustrating a configuration example of the hot water reservoir 10 and the backflow water drain 34 in the hot water supply system 100 according to the embodiment of the present invention. The warm water reservoir 10 stores warm water as described above, and includes, for example, the warm water tank 12 and the edge drainage pipe 13.

  The hot water tank 12 is a tank whose upper end is opened, and a water supply pipe 24 is connected in the vicinity of the upper end of the hot water tank 12. It is preferable to install the hot water tank 12 at a position where it can sufficiently receive solar heat, such as the roof of a house. The water supplied from the water supply 20 through the water supply pipe 24 is stored in the hot water tank 12. The stored water is heated by solar heat or the like to become warm water.

  The edge cutting drain pipe 13 is a drain pipe provided at a position below the position where the hot water tank 12 and the water supply pipe 24 are connected. The edge cut drain pipe 13 drains the warm water to the outside when the water level of the hot water stored in the hot water tank 12 exceeds the height of the edge cut drain pipe 13. Therefore, the water level of the warm water stored in the warm water tank 12 does not exceed the edge drainage pipe 13. Thereby, the warm water tank 12 can be made into the state cut off with the waterworks 20. FIG. In addition, as long as the hot water tank 12 can be in a state of being cut off from the water supply 20, a configuration other than the configuration in which the edge cutting drain pipe 13 is provided may be used.

  The supply water pressure supply unit 342 applies the pressure P1 in the vicinity of the entrance to the drainage unit 341 as the supply water pressure from the water supply 20 as described above, and reversely prevents the flow from the downstream of the water supply pipe 32 to the upstream. A stop valve 342a, a check valve 342b, and a pressure reducing valve 342c are provided. That is, the pressure P1 applied to the drainage part 341 becomes the pressure of the water supply pipe line 32 between the check valve 342a and the check valve 342b.

  A configuration in which the pressure between the connection portion of the water supply pipe 32 and the water supply pipe 21 and the check valve 342b is provided as the pressure P1 to the drainage unit 341 without providing the check valve 342a is also conceivable. Since there is a point, the structure in which the check valve 342a is provided is preferable.

  The problem is that when any one of the branch water supply valves 22a to 22d is operated to supply clean water to the outside through the clean water supply pipe 23, the supply water pressure of the clean water supplied to the water heater 30 decreases. It is to end. This becomes a problem particularly in a low water pressure region (for example, a region having a water pressure of 150 kPa to 200 kPa). When one of the branch water supply valves 22a to 22d is operated to perform branch water supply, and the water supply pressure supplied to the hot water heater 30 decreases rapidly as a result, the drain valve of FIG. When 400 is used, there is a possibility that the drain outlet 430 and the pressure receiving part 420 in the water pipe line communicate with each other, and the drain outlet 430 is opened. In this case, the water supplied from the water supply 20 is drained from the drain outlet 430 before reaching the mixing unit 33.

  If the check valve 342a is provided and the pressure of the water supply pipe 32 between the check valve 342a and the check valve 342b is set to the pressure P1, the supply water pressure of the water supplied to the water heater 30 is changed. However, the above problem does not occur. For this reason, the structure which provides the non-return valve 342a in the water supply pressure supply part 342 is preferable. Further, by providing the check valve 342a, the backflow prevention function in the water supply pipe line 32 can be strengthened.

  Further, it is preferable to use a check valve with a vacuum breaker as the check valve 342a. The check valve with a vacuum breaker is a check valve having a function of sucking air from the outside when the inside of the water supply pipe line 21 has a negative pressure. If a check valve with a vacuum breaker is used as the check valve 342a, air is sucked in from the outside when the inside of the water supply line 21 becomes negative pressure, so that the water supplied to the water heater 30 described in the above problem It is possible to avoid a decrease in the feed water pressure. Further, if a check valve with a vacuum breaker is used as the check valve 342a, air is sucked in from the outside when the inside of the water supply pipe 21 becomes negative pressure. Can be prevented.

  The check valve 342b may be replaced with another water flow resistance member that generates water flow resistance, and the water supply pressure supply unit 342 may be configured. This is because even with this configuration, a pressure difference can be generated between the pressure P1 and the pressure P2. Other water flow resistance members include, for example, a constant pressure valve, but are not limited thereto.

  The pressure reducing valve 342c reduces the pressure. If the pressure reducing valve 342c is provided between the check valve 342a and the check valve 342b as shown in FIG. 3, it is easy to generate a pressure difference between the pressure P1 and the pressure P2.

  As described above, the water supply line pressure supply unit 343 gives the drainage unit 341 with the pressure P2 in the predetermined area in the water supply line 32 located downstream of the area near the entrance as the pressure in the water supply line 32. 1 and includes check valves 342b and 343a for blocking the flow from the downstream to the upstream of the water pipe 32. That is, the pressure in the upper water pipe 32 applied to the drainage part 341 is the pressure of the upper water pipe 32 between the check valve 342b and the check valve 343a. In the configuration of the water supply pressure supply unit 342 and the water supply line pressure supply unit 343, the check valve 342b has both configurations.

  When the check valve 342b is replaced with another water flow resistance member that generates water flow resistance, the other water flow resistance member that generates water flow resistance and the check valve 343a constitute the water supply pressure supply unit 343. Also good. Further, even when the check valve 342b is replaced with another water flow resistance member that generates water flow resistance, a separate check valve is provided, and the check valve and the check valve 343a provide a pressure supply unit in the upper water line. 343 may be configured. That is, the water supply pressure supply unit 342 and the water supply line pressure supply unit 343 can be configured by various combinations of the check valve and other water flow resistance members that generate water flow resistance.

  When the water supply pressure supply unit 342 and the water supply line pressure supply unit 343 are configured as described above, three check valves are provided together with the drainage unit 341, so that the backflow prevention function in the water supply line 32 is provided. It will be solid. Even if the check valve 342b is replaced with another water flow resistance member that generates water flow resistance, two check valves are provided together with the drainage portion 341, so that the backflow prevention function in the water supply pipe line 32 is provided. It will be solid.

  Moreover, when the warm water reservoir 10 is configured as shown in FIG. 3, the warm water stored in the warm water reservoir 10 is treated as sewage under the Water Supply Law. For this reason, if this warm water or mixed water does not prevent the hot water or the mixed water from flowing back into the water supply line 20 from flowing back into the water supply line 20, the water supply law will be violated. With this configuration, it is possible to reliably prevent the warm water or mixed water from flowing back to the water supply 20 and solve the problems in the water supply law.

  As described above, according to the embodiment of the present invention, the hot water supply 30 receives the hot water supply from the hot water storage unit 10 and the clean water supply from the water supply 20 and mixes them in the hot water supply 30 (mixing unit 33). ), It is possible to reliably drain the warm water or mixed water that has flowed back into the water pipe 32 to the outside by the function of the backflow water drainage section 34.

  Further, by providing the water supply pressure supply unit 342 and the water supply line pressure supply unit 343, the drainage unit 341 can be stably operated even when the water supply pressure of the water supply 20 is lowered. Furthermore, by configuring the water supply pressure supply unit 342 and the water supply line pressure supply unit 343 with check valves, the operation of the drainage unit 341 can be stabilized and the backflow prevention function can be strengthened.

  The embodiment of the present invention shows an example for embodying the present invention, and the present invention is not limited to this, and various modifications can be made without departing from the gist of the present invention. .

It is a figure which shows the hot water supply system 100 in embodiment of this invention. It is a figure which shows the drain valve 400 which is an example of the drainage part 341 in the hot water supply system 100 in embodiment of this invention. It is a figure which shows one structural example of the backflow water drainage part 34 in the hot water supply system 100 in embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Warm water storage part 11 Warm water supply pipe 12 Warm water tank 13 Edge cutting drain pipe 20 Water supply 21, 23, 24 Water supply pipe 22a, 22b, 22c, 22d Branch water supply valve 30 Water heater 31 Hot water pipe 32, 32a, 32b Water supply pipe Path 33, 38 Mixing section 34 Backflow water drainage section 35a, 35b Mixed water pipe 36 Heat exchanger 37 Heating water pipe 39 Mixed water supply pipe 100 Hot water supply system 341 Drainage section 342 Feed water pressure supply section 342a, 342b, 343a Check valve 342c Pressure reducing valve 343 Water supply pipe internal pressure supply part 343a Check valve 400 Drain valve 410 Water supply pressure receiving part 411, 421 Tubular member 412, 422 Opening 420 Water supply pipe internal pressure receiving part 430 Drain outlet 440 Drain outlet opening / closing control part 441 Piston 442 Valve element 443 Diaphragm 444 Spring member

Claims (8)

A water supply pipe for supplying water from the water supply,
Hot water storage means for storing hot water;
A hot water supply pipe for supplying hot water stored in the hot water storage means;
A water heater that mixes the clean water supplied from the clean water supply pipe and the warm water supplied from the warm water supply pipe to generate and supply mixed water of a desired temperature; and
The water heater includes a backflow water draining means for draining the backflowed hot water or the mixed water to the outside when the hot water or the mixed water supplied from the hot water supply pipe flows backward toward the water supply pipe. A hot water supply system characterized by A water pipe that is a passage of water supplied from the water supply,
A hot water pipe that is a passage of hot water supplied from hot water storage means for storing hot water;
A mixing means connected to the water supply pipe and the hot water pipe, mixing the clean water and hot water to generate mixed water having a desired temperature and supplying the mixed water downstream;
And a backflow water draining means for draining the backflowed warm water or mixed water to the outside when the warm water or mixed water flows back to the top water pipe. Water heater. The backflow water draining means is
A drainage means having a drainage port, and opening and closing the drainage port according to the magnitude of the water supply pressure from the water supply and the magnitude of the pressure in the water supply pipe,
Water supply pressure supply means for supplying the drainage means with the pressure in the vicinity of the entrance which is a predetermined area near the entrance of the clean water in the water supply pipe, as the supply water pressure from the water supply;
A water supply pressure supply means in the water supply pipe for providing the drainage means with a pressure in a predetermined area in the water supply pipe located downstream of the area near the entrance as a pressure in the water supply pipe. The water heater according to claim 2.   The drainage means opens the drain outlet when the magnitude of the water supply pressure is less than or equal to a predetermined pressure, and the magnitude of the water supply pressure when the magnitude of the water supply pressure is greater than or equal to the magnitude of the predetermined pressure. Is closed when the pressure in the upper water pipe is larger than the pressure, and the drain is opened when the water supply pressure is smaller than the pressure in the upper water pipe. The water heater according to claim 3. The water supply pressure supply means includes:
A first check valve for preventing a reverse flow from downstream to upstream of the water supply pipe provided in the vicinity of the inlet of the water supply in the water supply pipe;
A second check valve for preventing a reverse flow from downstream to upstream of the water supply pipe provided in the water supply pipe on the downstream side of the first check valve;
A first connecting pipe connecting the drain pipe and the upper water pipe between the first check valve and the second check valve;
The pressure in the water supply line between the first check valve and the second check valve is supplied to the drainage means through the first connection pipe as a supply water pressure from the water supply. The water heater according to claim 3. The water supply pressure supply means is
The second check valve;
A third check valve for preventing a reverse flow from the downstream to the upstream of the water supply pipe provided in the water supply pipe downstream of the second check valve;
Comprising a second connecting pipe connecting the drain pipe and the water supply line between the second check valve and the third check valve;
The pressure in the water supply pipe between the second check valve and the third check valve is given to the drainage means through the second connecting pipe as the pressure in the water supply pipe. The water heater according to claim 5.   The hot water heater according to claim 5 and 6, further comprising a pressure reducing valve in the water supply line between the first check valve and the second check valve.   8. The water heater according to claim 2, wherein the hot water storage means is connected to the water supply and is cut off from the water supply.

Images