JP2005283038A - Storage type water heater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a storage type water heater with a simple structure and an inexpensive cost, built in with a mixing valve not outputting high temperature hot water of 60°C or more even during failure, and capable of supplying hot water of a temperature desired by a user even when a supply hot water temperature varies in regard to a small storage type water heater installed beneath a washbowl or the like of an optimum temperature hot water outputting type built in with a mixing valve wherein hot water stored at high temperature is outputted at an optimum temperature. <P>SOLUTION: The storage type water heater has a hot water storage tank, a water supply pipe supplying water to the tank, a hot water pipe outputting hot water from the tank, and the mixing valve mixing water diverged from the hot water pipe and water diverged from the water supply pipe. A temperature sensor of the mixing valve is a shape memory alloy spring, and it has a structure wherein a water passing amount of a water side is constant, and only a water passing amount of a hot water side is controlled. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a hot water storage type water heater, and particularly to a small electric water heater suitable for local hot water supply such as under a washbasin.

Conventional hot water storage hot water heaters have a hot water storage tank that always stores hot water at the required temperature. Hot water storage hot water heaters use an oil water heater that uses kerosene as a heat source and electric hot water that uses an electric heater as a heat source. There is a vessel.
In addition, the electric water heater is a medium-sized electric water heater that can be stored in a hot water tank for 100 liters or more, and can be installed outdoors, and a small electric water heater that can be stored under a basin with a storage capacity of less than 100 liters. The present invention, which is divided into three, relates to an electric water heater having a tank capacity of 40 liters or less among small electric water heaters.

  In the case of a small electric water heater, since it is installed in a narrow space such as under a washbasin, it is a problem to further reduce the size of the electric water heater. In addition, because it is a hot water storage type water heater, hot water cannot be supplied if the hot water stored in the tank is used up, so it is effective to store hot water at a high temperature of around 80 ° C to use a large amount of hot water in a small space. is there.

  However, in the case where the hot water stored at a high temperature of 80 ° C. reaches the mixing tap at the end as it is, the user mixes with the water so that the hot water that comes out does not become hot by operating the mixing tap, and about 35 ° C. Hot water is discharged at an appropriate temperature, and hot water may come out and burns if the mixing tap is not operated carefully. Therefore, in recent years, there is an appropriate temperature hot water type in which hot water stored at a high temperature is adjusted to an appropriate temperature in the water heater, and the hot water temperature of the water heater is set to an appropriate temperature of about 35 ° C. in advance.

Such a suitable temperature hot water type has a built-in mixing valve that stores hot water at a high temperature of about 80 ° C in the tank and mixes the hot water and water just before the hot water is discharged from the water heater so that the temperature of the hot water becomes appropriate. It has a structure that adjusts the temperature.
The structure of a general heat-sensitive mixing valve is to install a temperature-sensitive component (for example, “Thermo Cartridge” using wax (trade name of NTC)) in the mixing chamber so that the temperature detected by the temperature-sensitive unit is at an appropriate temperature. Thus, the temperature is adjusted by adjusting the areas of the water supply portions on both sides of the water supply and hot water supply, and changing the amount of hot water and the amount of water so that the desired temperature is obtained.
Such a mixing valve that changes the amount of hot water is designed to be built in a faucet fitting that is generally operated by the user at the end, especially for the purpose of suppressing temperature changes when using a shower in a bathroom or the like. in use. In order to respond to temperature adjustments and changes in hot water usage when using the shower, a temperature setting unit and a flow rate adjustment unit are provided in the vicinity of the mixing valve or separately from the mixing valve. It is necessary to correspond to the temperature range. For this reason, the temperature and heat sensitive part of the mixing chamber has a hot water inlet arranged symmetrically with respect to the mixing chamber so that the hot water is sufficiently mixed, and the hot water is discharged in a direction perpendicular to the mixing chamber. It has a shape. However, if the mixing valve for changing the amount of hot water is built in the water heater, the structure of the internal piping becomes complicated, more space is required, the size increases, the number of parts increases, and the product cost increases. It will be high. Also, in the case of hot water / both water side control, the water side may be fully closed and the hot water side may be fully opened in the event of a malfunction of the mixing valve. In that case, hot water of about 80 ° C is discharged, which may cause burns. There is.
In recent years, there is a faucet fitting that uses a shape memory alloy spring as a temperature-sensitive component.
In this case, it is advantageous in that the responsiveness is faster than the “thermo cartridge” using wax, but like the “thermo cartridge”, the structure of the valve is complicated and high in cost. There is a disadvantage that hot water comes out.

  Therefore, in order to prevent hot water of 60 ° C or higher from coming out even if it breaks down, the water side of the mixing valve is opened with a fixed hole that does not change the area so that the mixing amount is always constant, and only the water flow rate on the hot water supply side There is a water heater with a built-in mixing valve that controls the temperature of the hot water and controls the temperature of the hot water. In the case of such a hot water side single-sided mixing valve, since the water flow control is performed only on the hot water side, the structure of the mixing valve is simple, inexpensive, and safe. However, the mixing valve with such a structure only uses a “thermo cartridge” for the temperature-sensitive part, and the temperature responsiveness at the time of mixing is poor, and the temperature of the hot water supply side, the water supply temperature, the original water pressure When fluctuating, there is a problem that the tapping temperature fluctuates 10 ° C. or more with respect to the target of about 35 ° C. Therefore, in order to bring the hot water supply temperature close to the desired temperature, the boiling water temperature of the hot water storage hot water heater is fixed at a high temperature of about 80 ° C., and the temperature cannot be adjusted.

On the other hand, the revision of “Act on the Rational Use of Energy” required that buildings with a total floor area other than houses of 2000m2 or more must be notified of energy conservation measures for hot water supply facilities, and awareness of energy conservation in recent products has increased. Therefore, it is necessary to take measures for energy saving for small electric water heaters.
Specifically, in the case of small electric water heaters, the timer function of energization time control that can set the boiling time using a weekly timer, etc. This is a learning power-saving function that saves power by reducing the energization time without reducing the warming temperature and reducing the heating time. In the learning power saving function, by detecting the time and the temperature of the hot water in the tank, it is possible to know at what time the hot water was used. When the time is not set, the heating temperature and the heat retention temperature are controlled to control the energization time. For example, when it is used in a toilet in an office building, store hot water such as 80 ° C during times when the hot water is frequently used for hand washing, such as before starting work or during lunch breaks, and during other times when it is less frequently used. The heat retention temperature is lowered to about 60 ° C., and the total power consumption of the heater due to boiling is suppressed to save power.

  When a mixing valve that controls only one side of the hot water side is built in a small electric water heater having such a learning power saving function, when the heat retaining temperature in the tank is reduced to 60 ° C. due to power saving, the mixing valve is turned on. The hot-water supply temperature will change and become lower than the appropriate temperature desired by the user. That is, there is a problem that the temperature desired by the user cannot always be provided in a use environment in which the temperature changes to the hot water supply temperature in addition to the water supply temperature and the water supply source pressure.

JP 2002-122353 A

  The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to incorporate a mixing valve for discharging hot water stored at high temperature in a small hot water heater installed under a basin or the like. With a suitable hot water supply type, a mixing valve that can supply hot water at a temperature desired by the user even if the water supply temperature or hot water supply temperature is variable, has a simple structure, is inexpensive, and does not contain hot water of 60 ° C or higher even in the event of a failure. The purpose is to supply a built-in hot water heater.

In order to achieve the above object, according to the first aspect of the present invention, a hot water storage tank, a water supply pipe for supplying water to the tank, a hot water discharge pipe for discharging hot water from the tank, and the hot water supply pipe and the water supply pipe are branched. A hot water heater having a mixing valve for mixing water, having a valve body for adjusting the amount of water flowing into the hot water heater, wherein the temperature-sensitive part of the mixing valve is a shape memory alloy spring, and the water side The hot water storage type hot water heater is characterized in that the water flow rate is constant and only the water flow rate on the hot water side is controlled.
According to claim 2, the hot water storage water heater according to claim 1, wherein the water supply amount is controlled by making the hole on the water supply side of the mixing valve elliptical.
According to claim 3, the hot water storage type according to claim 1, wherein the water supply amount is controlled by positioning the water supply side hole of the mixing valve at a position above or below the center of the cylindrical connection port. A water heater was used.
According to a fourth aspect of the present invention, the hot water storage water heater according to the first aspect is provided with a valve having a check mechanism in front of the hot water supply side of the mixing valve.
According to a fifth aspect of the present invention, there is provided the hot water storage type hot water heater according to the first aspect, wherein an orifice-shaped pressure loss plate for limiting the amount of water supply is mounted on the water supply side of the mixing valve.
According to claim 6, use detection means for detecting the use of hot water in the hot water storage tank, use detection time information storage means for recording use detection time information relating to the time detected by the use detection means, and the stored Control content determination means for determining the control content of the heater energization time based on use detection time information, and a temperature control unit for controlling the temperature in the hot water storage tank based on the determined control content of the heater energization time; The hot water storage water heater according to claim 1 having

According to the present invention, since hot water stored at a high temperature inside the water heater can be discharged at an appropriate temperature, there is no troublesome operation of the mixing tap by the user, and the hot water can be used comfortably. Even if the feed water temperature or the stored temperature changes, the tapping temperature does not change significantly. Even if the mixing valve fails, hot water of 60 ° C. or higher does not come out, which is safe.
In addition, in the learning power saving function that has the function of learning the usage time and changing the heat retention temperature, the user can reduce the maintenance cost by the power saving function, and even if the water supply temperature or the hot water supply temperature changes, the user can maintain an appropriate temperature of about 35 ° C. It becomes possible to use hot water.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic explanatory view of a hot water storage type hot water heater showing an embodiment of the present invention, FIGS. 2 to 4 are mixing valves showing an embodiment of the present invention, and FIGS. 5 to 6 are hot water storage type hot water of the present invention. It is an application example of a container.

  In FIG. 1, a hot water storage type hot water heater A is a local hot water supply type installed under a basin or the like, and is configured to supply hot water to a mixing faucet 11. A heater 2 for heating water is fixed to the hot water storage tank 1 of the hot water storage type water heater A. A thermistor fixing plate 14 is welded to the outer side of the body portion of the hot water storage tank 1, and a temperature adjusting thermistor 3 for detecting the water temperature in the hot water storage tank 1 is fixed to the thermistor fixing plate 14. 4 is a mixing valve for mixing hot water, 6 is a mixing valve water supply pipe for supplying water to the mixing valve 4, 7 is a tank outlet pipe for supplying hot water from the hot water storage tank 1 to the mixing valve, 8 is a hot water outlet, and 9 is for the hot water storage tank 1. Tank water supply pipes for supplying water, 10 is a water supply port, 12 is a water stop cock, 13 is a water supply flexible pipe connecting the water stop cock 12 to the water supply port 10, and 16 is a hot water outlet connecting the hot water outlet 8 to the mixed water tap 11. A flexible pipe 18 is a pressure reducing valve that keeps the pressure in the hot water storage tank 1 constant and regulates the flow rate, and 19 is a relief valve for releasing the expanded pressure during boiling.

  When energization of the hot water heater A is started while the hot water storage tank 1 is full, the heater 2 is energized until the temperature reaches a preset temperature by the control board 5 based on the information of the temperature control thermistor 3. Is called. During boiling, the expansion water is discharged from the relief valve 19. When the hot water side of the mixing faucet 11 is opened, water whose flow rate is controlled through the water supply flexible pipe 13, the water supply port 10, and the pressure reducing valve 18 enters the hot water storage tank 1 from the tank water supply pipe 9. Hot water boiled in the hot water storage tank 1 is supplied in such a manner that it is pushed out from the tank outlet pipe 7 to the mixing valve 4. On the other hand, water is supplied to the water side of the mixing valve 4 by the mixing valve water supply pipe 6, the temperature is adjusted to about 35 ° C. by the mixing valve 4, and the mixing valve hot water pipe 15 and the hot water outlet 8 through the hot water flexible pipe 16. As a result, approximately 35 ° C. hot water comes out of the mixing tap 11.

  FIG. 2 is a detailed view of the mixing valve 4 in the present invention. In the figure, the mixing valve 4 includes a mixing valve body 31, a hot water supply connection port 21, a water supply connection port 22, a mixed hot water connection port 23, a mixing chamber 36, a bias spring fixing portion 33, a shape memory alloy spring B, a hot water amount adjustment valve 34, A bias spring 32 is disposed. The bias spring fixing portion 33 has a hot water supply hole 24, and when hot water enters from the hot water supply connection port 21, variable hot water constituted between the bias spring fixing portion 33 and the hot water amount adjustment valve 34 through the hot water supply hole 24. Hot water is supplied to the mixing chamber 36 through the side water passage 37 and between the mixing valve body 31 and the hot water control valve 34. Water entering from the water supply connection port 22 is supplied to the mixing chamber 36 through a water supply hole 35 formed in the mixing valve body 31 and having a fixed diameter. A shape memory alloy spring B is set in the mixing chamber 36. In the shape memory alloy spring B, the spring load changes depending on the water temperature of the mixing chamber 36, the hot water amount adjustment valve 34 is operated by the balance of the spring load of the bias spring 32, and the opening degree of the hot water side water passage 37 is changed. Thereby, the temperature-controlled hot water is discharged from the mixed hot water connection port 23.

  In order to simplify the structure, the hot water supply connection port 21, the mixing chamber 36, and the mixed hot water connection port 23 are on the same axis. Therefore, when the flow rate is increased, the flow rate adjustment valve 34 is pushed by water pressure and pushed back more than the original spring strength of the shape memory alloy spring B, so that a lot of hot water flows and temperature control cannot be performed. Therefore, it is necessary to regulate the amount of water entering the hot water storage type hot water heater A by providing a flow rate adjusting mechanism such as a pressure reducing valve 18 or a constant flow rate valve (not shown). Thus, the hot water flow rate range is limited, and the hot water temperature can be a desired temperature even if the hot water connection port 21, the mixing chamber 36, and the mixed hot water connection port 23 are on the same axis. Also, in the unlikely event that the shape memory alloy spring B loses its spring load due to metal fatigue or the like, or dust or the like is caught between the mixing valve body 31 and the hot water amount adjusting valve 34, the hot water amount adjusting valve 34 will not operate, and the hot water side water passage Even if the passage area of 37 is maximized, the water supply hole 35 is not blocked by the fixing hole. The diameter of the hole is set in advance so that the mixed hot water temperature is 60 ° C. or less in the ratio of the hot water amount and the water amount when the passage area of the hot water side water passage 37 is maximized. Therefore, hot water of 60 ° C. or higher does not come out even if a failure occurs.

  By adopting such a structure, the mixing valve 4 using the shape memory alloy spring B has better responsiveness than the heat sensitive part made of wax contained in the case, and instantaneously adjusts the opening degree of the hot water side water passage 37. Therefore, there is no fluctuating temperature that causes discomfort to the user, such as overshoot in which hot water instantly appears at the beginning of water discharge, and undershoot in which low-temperature water immediately emerges. It is possible to provide. Also, even if the temperature of the hot water storage tank 1 changes due to a change in the temperature of the hot water supply due to seasonal fluctuations, the user changes the set temperature of the hot water heater A, or the power saving learning function, the hot water supply flow rate is limited. Therefore, although having a simple structure, it is possible to discharge hot water at an appropriate temperature from the mixed hot water connection port 23. In addition, since the water side always has a water supply hole and is not blocked, the structure is simple, the number of parts is small, the size can be reduced, and the bias spring 32 and the shape memory alloy spring B fail. Even if the hot water control valve 34 cannot be controlled normally, the mixing temperature coming out of the mixed hot water connection port 23 can be controlled to be 60 ° C. or less, and the user may be burned momentarily. Absent.

  Further, the bias spring fixing portion 33 is threaded on the outer diameter portion of the cylinder, and is fixed by screwing into the female screw processing portion 38 corresponding to the fitting portion of the mixing valve body 31, so that the deflection load of the bias spring 32 is applied. It is possible to adjust the temperature by making it variable. Thereby, since the temperature adjustment work generated at the time of production can be easily performed by adjusting the screws without changing the parts, it is possible to save time and reduce the cost.

  FIG. 3 is a water supply hole 35 viewed from the water supply connection port 22 of the mixing valve 4. The temperature of the hot water is adjusted by changing the amount of hot water mixed by changing the hot water side water passage 37 which is a gap between the bias spring fixing portion 33 and the hot water amount adjusting valve 34. The mixing of water and hot water in the mixing chamber 36 is performed. The sensitivity of the shape memory alloy spring B deteriorates due to the balance of the water pressure on the water supply side and the hot water supply side, and the mixing temperature changes. Therefore, the water supply hole 35 has an elliptical shape so that water and hot water are sufficiently mixed in the mixing chamber 36. This makes it possible to increase the water passage area as compared to supplying water in a circular manner, and to mix the hot water with the hot water in a wide range, so that the hot water is uniformly mixed and more accurate control is possible.

  FIG. 4 shows the water supply hole 35 as seen from the water supply connection port 22 of the mixing valve 4 in the same manner, but the position of the hole is shifted upward with respect to the center of the cylinder. Thereby, compared with the case where water is supplied at the center, the water is mixed in a whirling manner with respect to the hot water in the mixing chamber 36, so that the hot water is uniformly mixed and control with higher accuracy is possible.

  FIG. 5 shows an application example of the hot water storage type water heater in the present invention. A check valve 17 having a check mechanism is disposed on the upstream side of the mixing valve 4 in the middle of the tank outlet pipe 7 for supplying hot water to the mixing valve 4. When energization of the hot water storage water heater A is started while the hot water storage tank 1 is full, the heater 2 is energized by the control board 5 until the temperature reaches a preset temperature based on the information of the temperature control thermistor 3. . During boiling, the expansion water is discharged from the relief valve 19. Since the expanded water rises until the temperature in the hot water storage tank 1 reaches the set temperature, the temperature is also transferred to the tank outlet pipe 7 due to the influence. When there is no check valve 17, heat is also transferred to the mixing valve 4, and the temperature may rise to the mixed hot water connection port 23 of the mixing valve 4. In that case, when the user opens the hot water side of the mixing tap 11, hot water may be instantaneously discharged. However, since heat transfer is blocked by the check valve 17, the inside of the mixing valve 4 does not become hot.

  In FIG. 6, an orifice 20 is arranged between the mixing valve water supply pipe 6 and the mixing valve 4 on the upstream side of the water supply connection port 22 of the mixing valve 4. The orifice 20 has a water supply hole of about φ5 and is set so that the water supply pressure to the mixing valve 4 decreases. The hot water storage heater has a built-in pressure reducing valve 18, but the pressure supplied from the pressure reducing valve 18 to the hot water supply connection port 21 of the mixing valve 4 and the water supply pressure supplied to the water supply connection port 22 are on the water supply side. Since the pressure loss differs depending on the distance, bending, and shape of the path and the hot water supply path, the pressure does not always become the same, and the hot water supply pressure falls below the water supply pressure. Therefore, by adding pressure loss to the water supply side by the orifice 20, the pressures of the hot water supply connection port 21 and the water supply connection port 22 of the mixing valve 4 become substantially the same pressure, and the temperature performance of the mixing valve 4 is stabilized. . The pressure on the water supply side and the pressure on the hot water supply side vary depending on the model depending on the size of the hot water storage tank 1 of the hot water storage water heater, the shape of the tank water supply pipe 9, the tank outlet pipe 7, and the mixing valve water supply pipe 6 and the number of bends and diameters. To do. Therefore, by changing the hole diameter of the orifice 20 for each type of hot water heater, it is possible to set the optimum pressure balance for each model, the temperature performance is stable, and different hot water heaters are used. The same mixing valve can be used.

  The present invention relates to an electric water heater useful for local hot water supply such as under a washbasin.

It is typical explanatory drawing of the hot water storage type water heater which shows the Example of this invention. It is a typical structure figure of the mixing valve which shows the example of the present invention. It is the typical explanatory view which changed the shape of the mixing valve water supply side hole of the present invention. It is the typical explanatory view which changed the hole position same as the above. It is typical explanatory drawing of the electric heat prevention of the hot water storage type water heater which shows the application example of this invention. It is typical explanatory drawing for adjusting the pressure of a hot water storage type water heater same as the above.

Explanation of symbols

A ... Hot water storage water heater B ... Shape memory alloy spring 1 ... Hot water storage tank 2 ... Heater 3 ... Temperature control thermistor 4 ... Mixing valve 5 ... Control board 6 ... Mixing valve water supply pipe 7 ... Tank outlet pipe 8 ... Hot water outlet 9 ... Tank Water supply pipe 10 ... Water supply port 11 ... Mixing faucet 12 ... Stop cock 13 ... Water supply flexible pipe 14 ... Thermistor fixing plate 15 ... Mixing valve hot water pipe 16 ... Hot water flexible pipe 17 ... Check valve 18 ... Pressure reducing valve 19 ... Relief valve 20 ... Orifice 21 ... Hot water supply connection port 22 ... Water supply connection port 23 ... Mixed hot water connection port 24 ... Hot water supply hole 31 ... Mixing valve body 32 ... Bias spring 33 ... Bias spring fixing part 34 ... Hot water control valve 35 ... Water supply hole 36 ... Mixing chamber 37 ... Hot water side water passage 38 ... Female thread processing part

Claims (6)

In a hot water storage water heater having a hot water storage tank, a water supply pipe for supplying water to the tank, a hot water discharge pipe for discharging hot water from the tank, and a mixing valve for mixing water branched from the hot water supply pipe and the water supply pipe, Having a valve body for adjusting the amount of water flowing into the vessel, the temperature heat sensitive part of the mixing valve is a shape memory alloy spring, and the water flow rate on the water side is constant and only the water flow rate on the hot water side is controlled Hot water storage water heater that is characterized by The hot water storage type hot water heater according to claim 1, wherein the water supply amount is controlled by making an elliptical hole on the water supply side of the mixing valve. The hot water storage water heater according to claim 1, wherein the water supply amount is controlled by positioning the water supply side hole of the mixing valve above or below the center of the cylindrical connection port. The hot water storage type water heater according to claim 1, wherein a valve having a check mechanism is mounted in front of the hot water supply side of the mixing valve. The hot water storage type hot water heater according to claim 1, wherein an orifice-shaped pressure loss plate for limiting the amount of water supply is mounted on the water supply side of the mixing valve. Based on the use detection means for detecting the use of hot water in the hot water storage tank, the use detection time information storage means for recording use detection time information relating to the time detected by the use detection means, and the stored use detection time information The control content determination means for determining the control content of the heater energization time, and a temperature control unit for controlling the temperature in the hot water storage tank based on the determined control content of the heater energization time. No hot water heater.

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