JP2016191484A - Hot water storage tank unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a user-friendly storage water heater that can suppress reduction of water pressure when a user uses hot water at a hot water supply terminal, and provide a hot water storage tank unit that enables reduction in material cost and the weight of a hot water storage unit by reducing the thickness of a stainless steel plate of a hot water storage tank.SOLUTION: A hot water storage tank unit of a storage water heater for boiling up liquid in a hot water storage tank by using a heat pump cycle and an electric heater as a heat source includes: a hot water storage tank; an outer casing for accommodating the hot water storage tank; and a foam heat insulating material filled between the hot water storage tank and the outer casing. In the hot water storage tank unit, the thickness of a plate material constituting the hot water storage tank is less than 0.7 mm.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a hot water storage tank used in a hot water storage tank unit.

  Conventionally, a hot water storage type hot water heater having a boiling function that uses a heat pump cycle or an electric heater using midnight power or the like to heat low temperature water and store hot water of a desired temperature in a hot water storage tank is known. . In a hot water storage type hot water heater using a heat pump cycle, the low temperature hot water stored in the lower part of the hot water tank is heated by a heat source unit using the heat pump cycle, and converted into hot hot water and returned to the upper part of the hot water tank. The water is boiled. In a hot water storage type water heater using an electric heater, low temperature hot water in the hot water storage tank is heated by an electric heater provided in the hot water storage tank, and the hot water is stored in the hot water storage tank. In this way, hot water storage hot water heaters use hot water that has been stored in a hot water storage tank by boiling it up with a heat pump cycle or an electric heater. Since it takes time to complete the operation, it is a system that performs boiling operation within midnight hours and uses the stored hot water for hot water supply. For this reason, the structure of a hot water storage unit provided with a hot water storage tank is generally a structure in which a heat insulating material formed of foamed polystyrene or the like is provided on the entire circumference of the hot water storage tank and an outer plate is attached so as to cover the hot water storage unit and the heat insulating material. .

  In addition, the hot water storage type hot water heater has a function of adjusting the amount of heat stored in the hot water storage tank by changing the temperature during the boiling operation according to the amount of hot water used by the user (for example, 65 ° C. to 90 ° C.). In addition, when hot water is supplied to the home or the like, the hot water stored in the hot water storage tank and tap water are mixed and supplied from the hot water supply terminal as an arbitrary temperature desired by the user.

  The hot water storage tanks used in such hot water storage hot water heaters are used to reduce the water pressure between the water supply section and the hot water storage tank in order to prevent the water pressure from the water supply from being directly applied to the hot water storage tank and deformed or damaged. A pressure reducing valve is provided. However, when the user opens the hot water supply terminal to supply hot water, the pressure applied to the hot water storage tank is close to the atmospheric pressure, but when the hot water supply terminal is closed, the hot water storage tank has a pressure reducing valve. The set pressure is applied, and the hot water storage tank is subjected to repeated pressure fluctuations as the user uses the hot water. When boiling water in the hot water storage tank, pressure is applied to the hot water storage tank due to expansion of the water accompanying the boiling, and the pressure accompanying this expansion takes various values by changing the boiling temperature. For this reason, in order to prevent damage to the hot water storage tank due to repeated pressure fluctuations applied to the hot water storage tank, a pressure reducing valve for reducing tap water pressure was provided at the hot water supply port, and the pressure in the hot water storage tank increased too much. In this case, a pressure relief valve for reducing the pressure in the tank is provided to suppress pressure fluctuations, and the thickness of the stainless steel plate, which is a material for the hot water storage tank, is increased.

JP 2009-228981 A JP 2011-117694 A

  However, if the thickness of the stainless steel plate in the hot water storage tank is increased, the weight of the completed hot water storage unit will be increased, the installation workability will be worsened, and the material cost will be increased by increasing the thickness. there were. Also, there is a method to lower the pressure set by the pressure reducing valve in order to reduce the pressure resistance of the hot water storage tank, but in this case the water pressure when the user uses it at the hot water supply terminal is reduced, so shower pressure etc However, there is a problem that the usability of the user is deteriorated.

  The present invention that solves the above-mentioned problems includes a hot water storage tank, an outer box that accommodates the hot water storage tank, and a hot water storage tank unit that is filled between the hot water storage tank and the outer box. The thickness of the plate material constituting the plate is less than 0.7 mm.

  Further, the present invention for solving the above-mentioned problems is a hot water storage tank unit having a hot water storage tank, an outer box containing the hot water storage tank, and a foamed heat insulating material filled between the hot water storage tank and the outer box. In the hot water storage unit in which the thickness of the plate constituting the hot water storage tank is less than 0.7 mm, the minimum gap formed by the hot water storage tank and the outer box is 5 mm or more.

  ADVANTAGE OF THE INVENTION According to this invention, while suppressing the reduction of the water pressure at the time of a user using with a hot water supply terminal, while being able to provide an easy-to-use hot water storage type hot water heater, the material cost is reduced by reducing the thickness of the stainless steel plate of the hot water storage tank. It is possible to provide a hot water storage tank unit that reduces costs and reduces the weight of the hot water storage unit.

It is a whole lineblock diagram showing the hot water storage type hot water heater provided with the hot water storage tank unit concerning this embodiment. It is a perspective view which shows the inside of a hot water storage tank unit. It is explanatory drawing of the filling method of a foam heat insulating material. It is a cross-sectional view of a hot water storage tank unit. It is a schematic diagram of the reaction force with respect to the force by the water pressure in the hot water storage tank in a present Example. It is a schematic diagram regarding the force by the water pressure in the hot water storage tank in the conventional hot water storage unit.

  The form of the hot water storage tank unit for carrying out the present invention will be described in detail with reference to the drawings as appropriate.

First, the water heater 1 provided with the hot water storage tank unit 1A will be described with reference to FIG. FIG. 1 is an overall configuration diagram showing a water heater provided with a hot water storage tank unit according to the present embodiment. As shown in FIG. 1, the water heater 1 includes a hot water storage tank unit 1A and a heat pump unit 10.
It is comprised including. The hot water storage tank unit 1A includes a hot water storage tank 2, an outer box 3A, a vacuum heat insulating material 4A (not shown because it is not visible in FIG. 1), and a foam heat insulating material 6 (portion indicated by dots).

  A water supply pipe 11 into which tap water is introduced is connected to the lower part of the hot water storage tank 2. The water in the lower part of the hot water storage tank 2 is introduced into the heat pump unit 10 via the water inlet pipe 12 by a pump (not shown). Hot water heated by the heat pump unit 10 is introduced into the upper part of the hot water storage tank 2 through the hot water discharge pipe 13. The temperature of the hot water in such a hot water storage tank 2 increases, for example, as it goes upward from the lower side in the vertical direction. That is, the temperature distribution is relatively low, medium and high from the lower part to the upper part in the hot water storage tank 2. For example, the temperature is about 90 ° C. at the upper part of the hot water storage tank 2 and about 50 ° C. at the intermediate part.

  The heat pump unit 10 boils water taken out from the hot water storage tank 2, compresses a refrigerant (for example, carbon dioxide) to high temperature and high pressure, and dissipates heat from the refrigerant discharged from the compressor. A water-refrigerant heat exchanger that is heated by exchanging heat with water from the hot water storage tank 2, a pressure reducing valve that decompresses the refrigerant from the water-refrigerant heat exchanger, and a refrigerant that absorbs heat in the atmosphere and depressurizes the refrigerant. It comprises a heat pump cycle in which an evaporator to be evaporated is connected in a tubular shape by piping.

  Hot water taken out from the upper part of the hot water storage tank 2 passes through the hot water supply pipe 14 and is mixed with water from a branched water supply pipe (not shown) branched and connected to the water supply pipe 11 via a mixing valve (not shown). Then, hot water is supplied from the hot water supply terminal 18 through the hot water supply pipe 17.

  The outer box 3A has a space for accommodating the hot water storage tank 2, and includes a pipe cover 3s on the front side (front side). The piping cover 3s has a space for accommodating a hot water discharge pipe 13, a branch water supply pipe (not shown), a mixing valve (not shown), a hot water supply pipe 17 and the like from the heat pump unit 10 toward the hot water storage tank 2. And the product leg 60 is installed in the baseplate 3e so that it may connect with the tank leg 5. FIG.

  FIG. 2 is a perspective view showing the inside of the hot water tank unit 1A according to the present embodiment. In addition, in FIG. 2, the state inside 3 A of outer boxes when the pipe cover 3s (refer FIG. 1) side is cut | disconnected is shown. Moreover, in FIG. 2, illustration of the foam heat insulating material 6 (refer FIG. 1) and various piping is abbreviate | omitted.

  As shown in FIG. 2, the hot water storage tank 2 includes a cylindrical body plate 2a and a substantially bowl-shaped (hemispherical, bowl-shaped) upper end plate 2b that covers the upper opening of the body plate 2a with a material such as stainless steel, for example. The lower end plate 2c having a generally bowl shape (hemispherical, bowl-shaped) covering the lower opening of the body plate 2a is welded.

  The hot water storage tank 2 includes three tank legs 5, and the lower ends of the tank legs 5 are fixed to the outer box 3A with bolts or the like. The number of tank legs 5 is not limited to three, but may be four or more. However, considering the earthquake resistance of the hot water storage tank 2, in the case of three, all tank legs 5 are Since it is grounded, it can be fixed stably without floating. In this case, the cost can be reduced as compared with the case where four or more are provided, which is more preferable.

  Moreover, temperature sensors 80a and 80b (thermistors) are provided on the outer surface (front surface) of the hot water storage tank 2 at intervals in the vertical direction. The upper temperature sensor 80 a detects the boiling temperature that is the temperature of the upper part of the hot water storage tank 2. The lower temperature sensor 80 b detects the temperature of the intermediate temperature water in the intermediate portion of the hot water storage tank 2. The number of temperature sensors 80a and 80b is not limited to the present embodiment, and is not limited to the upper part of the hot water storage tank 2, but is configured to have three or more temperature sensors from the upper part to the lower part of the hot water storage tank 2. There may be. Based on the information from the temperature sensor, the amount of hot water stored in the hot water storage tank 2 is grasped, and from this information, the amount of hot water used by the user is estimated, the amount of heat to be stored is determined, and the heat pump unit 10 The boiling temperature of hot water inside the hot water storage tank 2 is determined.

  The outer box 3A is made of a steel plate that accommodates the hot water storage tank 2, and is located at the front plate 3a (see FIG. 1) located at the front, the side plates 3b, 3b located at the side, and the rear of the hot water storage tank 2. The rear plate (back plate) 3c, the upper plate (top plate) 3d positioned above, and the bottom plate 3e positioned below are configured in a vertically long rectangular box shape.

  The piping cover 3s is provided in front of the outer box 3A. For example, the front cover of the outer box 3A is constituted by a front plate located on the front side, a side plate located on the left and right sides, an upper plate located on the upper side, and a bottom plate located on the bottom side. It is comprised so that 3a (refer FIG. 1) may be covered.

  Further, the leg receiving part 4 attaches the tank leg 5 to lay the outer box 3A sideways, and fills the stock solution of the foam heat insulating material 6 from the filling ports 3a1 and 3a2 (see FIG. 3 to be described later for details). It is installed in a position that does not directly touch 5. In other words, the rear plate 3c facing each other is directly seen from the filling ports 3a1 and 3a2 of the stock solution of the foam heat insulating material 6.

  As shown in FIG. 2, the tank leg 5 supports the hot water storage tank 2, and is arrange | positioned along the perpendicular direction (illustrated up-down direction). The tank legs 5 are formed by bending a sheet metal into a substantially L shape, etc., and are located near the radially outer side of the hot water tank 2 with a gap that does not contact the hot water tank 2. doing. In this way, by disposing the tank leg 5 radially outside the hot water storage tank 2, the hot water storage tank 2 can be supported more stably than when the tank leg is provided on the lower end plate.

  The product leg 60 supports the outer box 3A in which the hot water storage tank 2 is accommodated, and is fixed to the lower surface of the bottom plate 3e of the outer box 3A. Further, the product leg 60 is configured such that the product leg 60 is positioned at a position where the tank leg 5 overlaps with the product leg 60 when viewed in the vertical direction, in other words, vertically below the tank leg 5.

  A bottom plate 3 e that constitutes the bottom surface of the outer box 3 </ b> A is formed in a substantially square plate shape and is positioned below the lowermost portion of the hot water storage tank 2. The lower part of the hot water tank 2 (lower end panel 2c) is connected with a water supply pipe (not shown) through which tap water is introduced, piping for introducing the water in the hot water tank 2 into the heat pump unit 10 (see FIG. 1), and the like. Has been.

  Further, the bottom plate 3e is formed in a substantially square plate shape having an area slightly larger than, for example, a cross section of the hot water storage tank 2. Two tank legs 5 and 5 are located at the corners on the back side (rear side) of the bottom plate 3e, and one tank leg 5 is located on the front side.

  FIG. 3 shows a filling method of the foam insulation. In addition, the up-down direction and the front-back direction arrows shown in FIG. Moreover, in FIG. 3, illustration of the vacuum heat insulating material 4A is abbreviate | omitted.

  As shown in FIG. 3, the front plate 3a of the outer box 3A is formed with filling ports 3a1 and 3a2 that serve as inlets when filling the stock solution of the foam heat insulating material 6. The filling port 3a1 is formed in the upper part of the outer box 3A, and the filling port 3a2 is formed in the lower part of the outer box 3A.

  Then, in a state before attaching the piping cover 3s (see FIG. 1), the outer box 3A containing the hot water storage tank 2 was laid so that the upper and lower sides of the outer box 3A were horizontal and the front plate 3a was upward. Put it in a state.

  In the state where the outer box 3A is laid down in this way, the periphery of the outer box 3A is covered with a foam management jig (also referred to as yay) 30 (see the two-dot chain line in FIG. 3). The foam management jig 30 includes a plate-shaped jig that surrounds the entire periphery of the outer box 3A and presses all of the front plate 3a, the side plates 3b and 3b, the rear plate 3c, the upper plate 3d, and the bottom plate 3e. Then, the nozzle 31 is inserted into the filling ports 3a1 and 3a2 from the outside of the foam management jig 30, and the stock solution of the foam heat insulating material 6 is injected from the filling ports 3a1 and 3a2.

  As a result, the stock solution of the foam heat insulating material 6 first starts to accumulate from the rear side (the lower side in the figure) of the hot water storage tank 2 and rises toward the front side (the upper side in the figure) of the hot water storage tank 2 in the outer box 3A. And if the undiluted | stock solution of the foam heat insulating material 6 is inject | poured in 3A of outer boxes, foaming of the undiluted solution of the foam heat insulating material 6 will be started. At this time, since the entire outer surface of the outer box 3A is suppressed by the foam management jig 30, it is possible to prevent the outer box 3A from expanding (deforming) due to the foaming pressure when the foam heat insulating material 6 is foamed. it can. The foam heat insulating material 6 is cured after the foaming is completed. The hot water storage unit 1A forms the foam heat insulating material 6 by foaming the stock solution, and therefore does not provide an unfoamed portion of the foam heat insulating material 6, so that the hot water storage tank 2 and the outer box 3A are filled with the foam heat insulating material 6. The space formed by the vacuum heat insulating material 4A is provided with a distance of 5 mm or more, and the entire hot water storage tank 2 is covered with the foam heat insulating material 6. With this structure, when the stock solution of the foam heat insulating material 6 is foamed, the foam heat insulating material 6 is filled in the space between the hot water storage tank 2 and the outer box 3A without any gap as shown in FIG. Thus, the strength of the hot water storage tank 2 can be improved by filling the foamed heat insulating material 6 around the hot water storage tank 2 without a gap.

  The hot water storage tank 2 has a pressure reducing valve (not shown) for reducing the water pressure in the water supply pipe 11 and a downstream side of the pressure reducing valve in order to protect the can body from being destroyed by the pressure of the internal water. A pressure relief valve (not shown) is provided so that the water pressure in the hot water storage tank 2 does not become higher than a predetermined value.

  Since the pressure reducing valve is configured so that the pressure of water after depressurization by this pressure reducing valve becomes 170 kPa, and the pressure relief valve is set to open the valve when the water pressure becomes 190 kPa or more, In a conventional hot water storage tank unit that does not fill with the foam insulation 6, the thickness of the stainless steel plate of the hot water storage tank 2 is required to be 0.7 mm or more at minimum. The tank 2 may be deformed or damaged.

  Specifically, as shown in FIG. 6, since there is a space between the heat insulating material 90 provided on the entire circumference of the conventional hot water storage tank 2 and the outer box 3A, the water pressure applied to the hot water storage tank 2 is increased. It is necessary to hold the force F <b> 1 by the structure of the hot water storage tank 2 alone, and the thickness of the stainless steel plate of the hot water storage tank 2 is required.

  However, in the present embodiment, as shown in FIG. 5, the space between the hot water storage tank 2 and the outer box 3A is filled with the foam heat insulating material 6 without a gap, so that the force F1 due to the water pressure in the hot water storage tank 2 is reduced. In addition, not only the structure of the hot water storage tank 2 but also the force F2 due to the outer box 3A and the foam heat insulating material 6 is applied, so even if the thickness of the stainless steel plate of the hot water storage tank 2 is thin (for example, less than 0.7 mm), The hot water storage tank 2 can be prevented from being destroyed by the pressure.

According to the hot water storage type hot water supply apparatus according to the present embodiment as described above, it is possible to provide a hot water storage type hot water supply apparatus that is easy to use while suppressing a decrease in water pressure when the user uses the hot water supply terminal. It is possible to provide a hot water storage tank unit that reduces the material cost by reducing the thickness of the plate and reduces the weight of the hot water storage unit.

1A Hot water storage tank unit 1 Water heater 2 Hot water storage tank 2a Body plate 2b Upper end plate 2c Lower end plate 2c1 Projection 3A Outer box 3a Front plate 3b Side plate 3c Rear plate 3d Upper plate 3e Bottom plate 3a1, 3a2, 3c1, 3c2 Filling port 3s Piping cover 4 Leg support (leg support)
4A Vacuum heat insulating material 4a Edge 4b, 5s, 6c3 Bolt insertion hole 5 Tank leg 5a, 5b Leg 5a2, 5b2 Inner surface 5c Support plate 5c1 Bending part 6 Foam heat insulating material 10 Heat pump unit 11 Water supply pipe 12 Water inlet pipe 13 Hot water pipe 14 , 17 Hot water supply pipe 18 Hot water supply terminal 30 Foam management jig 31 Nozzle 60 Product leg 70, 71, 72 Degassing hole 80a, 80b Temperature sensor 90 Thermal insulation

Claims (4)

A hot water storage tank,
An outer box containing the hot water storage tank;
A foam heat insulating material filled between the hot water storage tank and the outer box;
In a hot water storage tank unit having
A hot water storage tank unit characterized in that the thickness of the plate material constituting the hot water storage tank is less than 0.7 mm.   The hot water storage tank unit according to claim 1, wherein a minimum gap formed by the hot water storage tank and the outer box is 5 mm or more.   A heat pump type hot water heater using the hot water storage tank unit according to claim 1 or 2.   An electric heater-type water heater using the hot water storage tank unit according to claim 1 or 2.

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