JP2010223502A - Storage water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a storage water heater capable of effectively using thermal energy of high-temperature expansion water for energy to boil supplied low-temperature water again. <P>SOLUTION: The storage water heater includes: a hot water storage tank; a heating means for heating water within the hot water storage tank; a water supply pipe for communicating and connecting the bottom of the hot water storage tank with a water supply port; a hot water delivery pipe for communicating and connecting the upper part of the hot water storage tank with a hot water delivery port; an expansion water discharge pipe for communicating and connecting the upper part of the hot water storage tank with an expansion water discharge port; and a pressure reducing valve provided in the middle of the water supply pipe and making water pressure made to flow in to the hot water storage tank approximately constant; and a relief valve provided in the middle of the expansion water discharge pipe and discharging the expansion water within the hot water storage tank of which volume is expanded by the heating means so as to make the pressure within the hot water storage tank approximately constant. The storage water heater further includes a heat exchange means for performing heat exchange between the expansion water discharge pipe from the upper part of the hot water storage tank to the relief valve and the water supply pipe from the pressure reducing valve to the bottom of the hot water storage tank. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a hot water storage type hot water supply device, and more particularly to heat exchange of expansion water discharged from a hot water storage tank.

  In a hot water storage type water heater, the volume of water expands in the process of heating the water in the hot water storage tank to make it hot, and as a result, the pressure in the hot water storage tank increases. In the conventional hot water heater, when the pressure exceeds a predetermined pressure, the expansion water is discharged to the outside by providing a relief valve that releases the valve to protect the hot water tank. (For example, refer to FIG. 1 of Patent Document 1).

  In addition, the release valve is also provided in the same path as the hot water outlet because it has the purpose of discharging this gas that has accumulated in the upper part of the hot water tank due to volatilization of dissolved oxygen contained in tap water, etc., and is therefore discharged. The temperature of the expansion water is extremely high.

  For example, when 5 ° C. water stored in a 35 L hot water storage tank is heated to 75 ° C., the 35 L water becomes about 36 L hot water, and about 1 L hot water that does not fit in the hot water storage tank is discharged without being used. Therefore, when converted into electric power, about 85 W is discarded. Thus, discharging the expanded water to the outside means that the heated water is purposely discarded, which is a mechanism that is contrary from the viewpoint of recent ecology.

In order to solve this problem, as shown in FIG. 1 of Patent Document 2, there is one that temporarily stores the discharged expanded water and returns it to the hot water discharge path by sucking it with a pump or the like. In such a case, separately from the mechanism for storing the expanded water necessary to fulfill the original purpose and the mechanism for returning the stored expanded water to the outlet path, the expanded water is discharged from the outlet path. Various mechanisms such as a backflow prevention mechanism for the hot water storage tank and a drainage mechanism different from the expansion water hot water storage tank from the relief valve when the pressure reducing valve breaks down are required, and there is a problem that the apparatus becomes too complicated.

JP 2002-372313 A (page 4, FIG. 1) JP 2007-333229 A (page 6, FIG. 1)

  The present invention has been made to solve the above problems, and the object of the present invention is to effectively use the thermal energy of high-temperature expansion water as the energy for boiling up the supplied low-temperature water again. It is to provide a hot water heater.

  In order to achieve the above object, according to the first aspect of the present invention, there is provided a hot water storage tank, heating means for heating water in the hot water storage tank, and a water supply pipe that connects the bottom of the hot water storage tank and a water supply port. A hot water pipe that communicates and connects the upper part of the hot water storage tank and the hot water outlet; an expansion water discharge pipe that communicates and connects the upper part of the hot water storage tank and the hot water outlet; and the hot water storage tank A pressure reducing valve for making the water pressure flowing into the tank approximately constant, and a pressure in the hot water storage tank that is provided in the middle of the expansion water discharge pipe and discharges the expansion water in the hot water storage tank that is volume-expanded by the heating means. In the hot water storage type water heater provided with a relief valve for making the pressure constant substantially constant, the expansion water discharge pipe between the upper part of the hot water storage tank and the relief valve and the bottom of the hot water storage tank from the pressure reducing valve Heat exchange with water supply pipe Was storage-type water heater, characterized in that it comprises a heat exchange means for the. With this configuration, the heat of the expansion water is transmitted to the water supply by the heat exchanger and the temperature is raised, so that the heat energy stored in the expansion water can be returned to the water heater as energy of the water supply without being discarded.

  According to a second aspect of the present invention, the heat exchanging means accumulates the water supplied from the water supply pipe in a tank-like container and allows the expansion water discharge pipe to pass through the water. As a result, the capacity of the feed water staying in the feed water pipe at the time of boiling can be adjusted to an amount appropriate for the amount of heat heated by the expanded water discharged until the boiling is completed. Can be prevented from rising excessively.

  According to a third aspect of the present invention, in the hot water storage type hot water heater according to the second aspect, the expansion water discharge pipe located in the heat exchange means has a spiral shape. As a result, the overall size of the heat exchanger can be made compact without changing the heat exchange area of the expanded water discharge pipe passing through the tank-like container.

  According to a fourth aspect of the present invention, in the hot water storage water heater according to the second or third aspect, the expanded water discharge pipe located in the heat exchange means has a bellows shape. Thereby, since the heat exchange area of expansion water increases more, it becomes possible to make the whole size as a heat exchanger further compact.

  According to the invention described in claim 5, the hot water storage tank, the heating means for heating the water in the hot water storage tank, the water supply pipe that connects the bottom of the hot water storage tank and the water supply port, and the hot water storage tank A hot water pipe that communicates and connects the upper part of the hot water and the hot water outlet; an expansion water discharge pipe that communicates and connects the upper part of the hot water storage tank and the expansion water discharge port; and a water pressure that flows into the hot water storage tank. A pressure reducing valve for making the pressure approximately constant, and a pressure in the hot water storage tank that is provided in the middle of the expansion water discharge pipe and discharges the expansion water in the hot water storage tank that is volume-expanded by the heating means. In the hot water storage water heater provided with a relief valve, an expansion water discharge pipe between the relief valve and the expansion water discharge port and a water supply pipe between the pressure reducing valve and the bottom of the hot water storage tank Heat exchange for heat exchange Was storage-type water heater, characterized in that it comprises a stage. Thereby, the heat of the expansion water is transmitted to the water supply by the heat exchanger and the temperature is raised, so that the heat energy stored in the expansion water can be returned to the water heater as the water supply energy without being discarded. Moreover, since the expansion water drain pipe after the relief valve is opened to the atmosphere, it is not necessary to take a pressure-resistant structure, and the heat exchange means can be made a simple structure.

  According to a sixth aspect of the present invention, in the hot water storage water heater according to the fourth aspect, the heat exchanging means accumulates the expansion water supplied from the expansion water discharge pipe in a tank-shaped container, The water supplied from the water supply pipe is allowed to pass therethrough. Thereby, since the expansion water can be accumulated in the tank-shaped container for heat exchange at atmospheric pressure, the tank-shaped container can be manufactured with a simple structure.

  According to a seventh aspect of the present invention, in the hot water storage water heater according to the fifth aspect, the water supply pipe located in the heat exchange means has a spiral shape. As a result, the overall size of the heat exchanger can be made compact without changing the heat exchange area of the water supply pipe passing through the tank-like container.

  According to the present invention, an object of the present invention is to be able to effectively use the thermal energy of high-temperature expanded water as energy for boiling again the supplied low-temperature water.

It is a block diagram which shows the 1st Example of this invention. It is sectional drawing which shows the heat exchange part integrated in a 1st Example. It is a block diagram which shows the 2nd Example of this invention. It is sectional drawing which shows the heat exchange part integrated in a 2nd Example.

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

FIG. 1 is a configuration diagram of a hot water storage water heater showing a first embodiment of the present invention. Moreover, FIG. 2 is sectional drawing which shows the heat exchange part integrated in a 1st Example.

Water from a water supply source (not shown) enters the hot water storage hot water heater 100 from the water supply port 1 and is depressurized by the pressure reducing valve 3 through the water supply pipe 2. After passing through the pressure reducing valve 3, the water is branched into a water discharge pipe 4 and a water supply pipe 5, and after passing through the water discharge pipe 4, water is supplied to the water side of a mixing faucet (not shown) through a water outlet 23. The water supply pipe 5 is connected to the tank lower portion 17 of the heat exchange tank 15 in the heat exchange unit 101 and passes through the heat exchange tank 15 of the heat exchange unit 101. After that, water is supplied to the hot water storage tank 7 through the water supply pipe 6 connected to the tank upper portion 18 of the heat exchange tank 15, and the water stored in the hot water storage tank 7 is heated by the heater 8 built in the hot water storage tank 7. It becomes. The hot water passes through the tap pipe 9 and is supplied to the hot water side of the mixing tap (not shown) through the tap 10.

  The heat exchange tank 15 is surrounded by a heat insulating material 21 so as to minimize the amount of heat exchanged in the heat exchange tank 15 to the outside.

  When the water stored in the hot water storage tank 7 is heated, the mixing faucet (not shown) is closed and there is no flow of water. At this time, the water stored in the hot water storage tank 7 is heated and volume-expanded to become high-temperature expanded water. This high-temperature expanded water passes through the expanded water discharge pipe 11 branched from the tap water pipe 9 and enters from the coil upper part 19 of the spiral heat exchange coil 16 installed inside the heat exchange tank 15 of the heat exchange unit 101. , Passes through the inside of the heat exchange coil 16, passes through the expansion water discharge pipe 12 connected to the coil lower part 20, passes through the relief valve 13, is opened to the atmospheric pressure, and is discharged from the expansion water discharge port 14 to the external discharge port (see FIG. (Not shown).

  Although the expanded water is flowing at the time of boiling, the water supply is in a stopped state. For this reason, the water side of the heat exchange unit 101 needs to have a capacity that can absorb the amount of heat supplied by the expanded water flowing continuously. Considering the case where the 5 ° C water stored in the 35L hot water storage tank mentioned above is heated to 75 ° C, about 1L of expanded water is discharged, but it is theoretically heat if it is considered that the heat has been completely exchanged. The capacity of the exchange tank 15 is about 1 L, which is the same amount as the expanded water, and the temperature in the heat exchange tank 15 at that time is 5 ° C. to 75 ° C. However, this calculation has no energy loss and is a case where heat is completely exchanged. In fact, the capacity of the heat exchange tank 15 may be a little smaller.

  In addition, the surface of the spiral heat exchange coil 16 is desirably a bellows shape in order to increase the surface area during heat exchange, or the surface of a straight tube is preferably a dimple shape.

FIG. 3 is a configuration diagram of a hot water storage water heater showing a second embodiment of the present invention. Moreover, FIG. 4 is sectional drawing which shows the heat exchange part integrated in a 2nd Example.

Water from a water supply source (not shown) enters the hot water storage hot water heater 100 </ b> A from the water supply port 1 and is decompressed by the pressure reducing valve 3 through the water supply pipe 2. After passing through the pressure reducing valve 3, the water is branched into a water discharge pipe 4 and a water supply pipe 5, and after passing through the water discharge pipe 4, water is supplied to the water side of a mixing faucet (not shown) through a water outlet 23. Further, the water supply pipe 5 is connected to the coil lower portion 17A of the heat exchange coil 16A in the heat exchange unit 101A and passes through the heat exchange coil 16A of the heat exchange unit 101A. Thereafter, the water supplied to the hot water storage tank 7 through the water supply pipe 6 connected to the coil upper part 18A of the heat exchange coil 16A, and the water stored in the hot water storage tank 7 by the heater 8 built in the hot water storage tank 7 is heated to hot water. It becomes. The hot water passes through the tap pipe 9 and is supplied to the hot water side of the mixing tap (not shown) through the tap 10.

  The heat exchange tank 15A of the heat exchange unit 101A is surrounded by a heat insulating material 21A so as to minimize the amount of heat exchanged in the heat exchange tank 15A being released to the outside.

  When the water stored in the hot water storage tank 7 is heated, the mixing faucet (not shown) is closed and there is no flow of water. At this time, the water stored in the hot water storage tank 7 is heated and volume-expanded to become high-temperature expanded water. This high-temperature expanded water passes through the expanded water discharge pipe 22A branched from the hot water discharge pipe 9 and the relief valve 13, and then is released to the atmosphere, passes through the expanded water discharge pipe 11A, and the tank upper portion 19A of the heat exchange tank 15A of the heat exchange section 101A. And accumulated in the heat exchange tank 15A of the heat exchange unit 101. Thereafter, the water passes through the expansion water drain pipe 12A connected to the tank lower portion 20A of the heat exchange tank 15A and is discharged from the expansion water drain port 14A to an external drain port (not shown).

  The heat exchanging part 101 of the water heater 101 is excellent in pressure resistance because the heat exchanging coil 16 is pipe-shaped but the pressure after depressurization is loaded by the pressure reducing valve 3, while the heat exchanging tank 15 is a container. Therefore, the structure becomes complicated to ensure pressure resistance. However, in the structure of the water heater 101A, since the heat exchanging part 101A is open to the atmosphere, the heat exchange tank 15A does not have to be a pressure vessel structure and can be manufactured by an inexpensive manufacturing method.

  The present invention relates to a hot water storage type water heater, and in particular, in the thermal energy of expansion water discharged from a hot water storage tank, it is possible to effectively use the energy by exchanging heat with the supplied water.

DESCRIPTION OF SYMBOLS 1 ... Water supply port 2 ... Water supply pipe 3 ... Pressure reducing valve 4 ... Water discharge pipe 5 ... Water supply pipe 6 ... Water supply pipe 7 ... Hot water storage tank 8 ... Heating heater 9 ... Hot water outlet pipe 10 ... Hot water outlet 11 ... Expansion water discharge pipe 11A ... Expansion water Discharge pipe 12 ... Expansion water discharge pipe 12A ... Expansion water drain pipe 13 ... Release valve 14 ... Expansion water drain port 14A ... Expansion water drain port 15 ... Heat exchange tank 15A ... Heat exchange tank 16 ... Heat exchange coil 16A ... Heat exchange coil DESCRIPTION OF SYMBOLS 17 ... Tank lower part 17A ... Coil lower part 18 ... Tank upper part 18A ... Coil upper part 19 ... Coil upper part 19A ... Tank upper part 20 ... Coil lower part 20A ... Tank lower part 21 ... Thermal insulation material 21A ... Thermal insulation material 22A ... Expansion water discharge pipe 23 ... Outlet DESCRIPTION OF SYMBOLS 100 ... Hot water storage type water heater 100A ... Water heater 101 ... Heat exchange part 101A ... Heat exchange part

Claims (7)

A hot water storage tank,
Heating means for heating the water in the hot water storage tank;
A water supply pipe connecting the bottom of the hot water storage tank and a water supply port, and
A hot water pipe connecting the upper part of the hot water storage tank and the hot water outlet;
An expansion water discharge pipe connecting the upper part of the hot water storage tank and the expansion water discharge port,
A pressure reducing valve provided in the middle of the water supply pipe for making the water pressure flowing into the hot water storage tank substantially constant;
A hot water storage provided with a relief valve provided in the middle of the expansion water discharge pipe for discharging the expansion water in the hot water storage tank volume-expanded by the heating means to make the pressure in the hot water storage tank substantially constant In the water heater,
Heat exchange means for exchanging heat between the expansion water discharge pipe from the upper part of the hot water storage tank to the relief valve and the water supply pipe from the pressure reducing valve to the bottom of the hot water storage tank was provided. Hot water storage water heater characterized by. The hot water storage water heater according to claim 1, wherein the heat exchanging means accumulates water supplied from the water supply pipe in a tank-like container and allows an expansion water discharge pipe to pass through the water. The hot water storage type hot water heater according to claim 2, wherein the expansion water discharge pipe located in the heat exchange means has a spiral shape. The hot-water storage water heater according to claim 2 or 3, wherein the expansion water discharge pipe located in the heat exchange means has a bellows shape. A hot water storage tank,
Heating means for heating the water in the hot water storage tank;
A water supply pipe connecting the bottom of the hot water storage tank and a water supply port, and
A hot water pipe connecting the upper part of the hot water storage tank and the hot water outlet;
An expansion water discharge pipe connecting the upper part of the hot water storage tank and the expansion water discharge port,
A pressure reducing valve provided in the middle of the water supply pipe for making the water pressure flowing into the hot water storage tank substantially constant;
A hot water storage type provided in the middle of the expansion water discharge pipe, and provided with a relief valve for discharging the expansion water in the hot water storage tank volume-expanded by the heating means to make the pressure in the hot water storage tank substantially constant In the water heater,
A heat exchanging means for exchanging heat between the expansion water discharge pipe from the relief valve to the expansion water discharge port and the water supply pipe from the pressure reducing valve to the bottom of the hot water storage tank; Hot water storage water heater characterized by. The said heat exchange means accumulate | stores the expansion water supplied from the said expansion water discharge pipe in the tank-shaped container, and allows the water supplied from the said water supply pipe to pass therethrough. Hot water heater. The hot water storage water heater according to claim 6, wherein a water supply pipe located in the heat exchange means has a spiral shape.

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