JPH0313499B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a hot water boiler that uses a hot water storage tank and a water heater as a heat source.

Conventional configuration and its problems Conventionally, this type of hot water boiler has a hot water tank 1 and a heat source 2 as its main components, as shown in Fig. 1, and the hot water tank 1 is connected to the heat source 2 by an outgoing pipe 3. , a circulation pump 4 and a check valve 5 were connected in the middle.
Further, the heat source 2 and the upper part of the hot water storage tank were connected by a return pipe 6 to form a circulation path. A water supply port 7 was provided at the bottom of the hot water storage tank 1, and a fuel supply port 8 was provided at the top.

With this configuration, first, in order to boil the water in the hot water storage tank 1, water is introduced into the heat source 2 by the circulation pump 4 and then ignited. The water that has passed through the heat source 2 and is heated is sent again to the upper part of the hot water storage tank through the hot water tap 6 and is gradually heated up. When the set temperature is detected by a thermistor 9 attached to the lower part of the hot water storage tank 1, the pump 4 is stopped and combustion is also stopped. At the same time when a faucet 10 provided at the tip of the hot water supply port 8 is opened, water flows into the hot water storage tank 1 from the water supply port 7 directly connected to the water pipe, and hot water is discharged from the hot water supply port 8 like a piston. At this time, when the hot water level is continuously pushed upward, the thermistor 9 detects that the temperature is below the set temperature, and the circulation pump 4 is started to perform additional heating using the heat source 2.

In the above-mentioned hot water boiler, when boiling up the inside of the hot water storage tank, the hot water that blows out from the return pipe 6 is forced to convect inside the hot water storage tank and gradually boils up the whole tank. Even if you do not need the full amount of hot water, you must always store the full amount of hot water.

As a result, the heat radiation loss from the hot water storage tank, which is unique to hot water boilers, cannot be reduced, and the use of these systems is uneconomical. In addition, even though the entire body is boiled, due to the difference in density, there is a tendency for hot water temperature distribution to occur vertically inside the hot water storage tank 1, and a layer of high temperature hot water tends to form especially in the area above the return pipe 6. It was strong. When hot water is supplied from the hot water storage tank 1 having such a temperature distribution, the temperature of the hot water changes during the supply, which is extremely uncomfortable, for example, when using a shower or the like. In addition, if the hot water in the hot water tank is used up, that is, if the hot water runs out, with this type of hot water boiler,
Since the entire hot water tank 1 had to be heated, the waiting time was long.

Purpose of the Invention The present invention solves these conventional problems by stratifying hot water produced from a heat source from the top of a hot water storage tank, varying the amount of stored hot water as needed, and minimizing heat radiation loss. The purpose is to reduce the width of the temperature distribution as much as possible and to reduce changes in hot water supply temperature.

Structure of the Invention In order to achieve the above object, the present invention provides a hot water boiler in which a hot water storage tank having a water inlet and a hot water inlet, an outgoing pipe, a circulation pump, and a return pipe are connected in this order. It is installed at the top of the hot water storage tank, and the return pipe is connected to the top surface of the hot water storage tank, but the cross-sectional area near its tip is expanded, or the cross-sectional area of the flow path is expanded at the same position by a separate member. Furthermore, a diffusion plate is provided within this enlarged portion facing the opening of the return pipe.

With this configuration, the hot water injected from the return pipe has its flow velocity attenuated by the diffusion plate and the expansion part and flows into the hot water storage tank, so although the flow direction is downward, it spreads upward or sideways due to the density difference, so hot water is can be stratified from the upper part of the hot water storage tank, and the temperature distribution can also be reduced. Also, for the same reason, the amount of stored hot water can be set freely.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.
This will be explained using figures. In addition, in the figure, the same parts as in FIG. 4 are given the same numbers.

In the figure, a hot water storage tank 1 with a water supply port 7 at the bottom
An outgoing pipe is connected to the other lower part of the pump, and a circulation pump 4, a heat source 2, and a return pipe 6 are connected in this order. A hot water supply port 8 is provided at the top of the hot water storage tank, and a return pipe 6 is connected to the top surface of the hot water storage tank. In this example, the return pipe 6 is directly connected to the upper surface of the hot water storage tank 1 without enlarging its tip, and an expanding member 11 is installed inside the hot water storage tank. This member is generally an annular ring with an open bottom end, and a diffusion plate 12 having an annular flange around the periphery thereof is provided inside the diffusion plate 12 facing the opening of the return pipe 6. In addition, thermistor 9 is a thermistor for full hot water storage, and 9' is a thermistor for half hot water storage.
Both are fixed to the surface of the hot water tank.

In the above configuration, the operation for boiling up the inside of the hot water tank will be explained first. In the figure, circulation pump 4
The water is sucked from the lower part of the hot water storage tank through the outgoing pipe 3, and then returned to the hot water storage tank 1 through the heat source 2 and return pipe 6. Upon detecting this flow, the heat source 2 is ignited and starts combustion.

When the hot water heated by the heat source 2 is ejected from the return pipe 6 into the hot water storage tank 1, it collides with the diffuser plate 12 having a brim, so that the flow is changed from horizontal to upward and impinges on the inner surface of the hot water storage tank 1. After the flow rate is attenuated, it hits the expanding member 11.

Therefore, the flow is expanded to the diameter of the expanding member 10 and flows into the hot water storage tank, but since the flow velocity is attenuated, as shown in Fig. 2, when boiling starts, it is caused by the density difference with the cold water around the expanding member. Due to the upward buoyant force, the direction of the flow changes toward the top of the hot water storage tank. For this reason, hot water is stratified from the top of the hot water storage tank. As the hot water gradually accumulates and becomes hot water around the expanding member, as shown in Figure 3, the hot water flowing from the expanding member will no longer have a density difference, so it will not flow upwards, but the flow velocity will be attenuated, so it will flow around the expanding member. Spread. In this way, the hot water is stratified from the top of the hot water storage tank without convection or stirring. For example, when a layer of hot water comes down to the thermistor 9', it is detected that half of the hot water storage has been completed, and the hot water is stratified up to the thermistor 9. Then, it is detected that all hot water storage has been completed. Although not shown, the hot water storage amount can be set using a button on the controller or the like.

When you pour out the hot water that has been boiled as described above,
Water flows in from the water supply port 7 and pushes up the hot water in the hot water tank 1. When a layer of water is formed at the bottom of the hot water storage tank, for example, when a layer of water is formed up to the thermistor 9 when the hot water is fully stored, reheating is started, the circulation pump 4 is rotated, and the heat source 2 is ignited again.

Therefore, according to this embodiment, at the time of boiling, the hot water spouted from the return pipe 6 is first disposed between the diffusion plate 12 and the expansion member 1.
1, the flow is sufficiently expanded and the flow velocity is attenuated, so there is no convection or stirring inside the hot water storage tank, and the hot water is gradually stratified from the top of the hot water storage tank. Therefore, by using two thermistors for detecting hot water temperature as in this embodiment, the amount of stored hot water can be divided into two levels.

Since hot water can be stored according to the amount of hot water used,
Heat radiation loss from the hot water storage tank 1 can be minimized and economical efficiency can be improved. In addition, since the temperature distribution of stored hot water is small, changes in hot water supply temperature are also small.
There is no discomfort even when using the shower etc. In addition, in the event that the hot water runs out, the system stores hot water from the top of the tank, so hot water can be obtained in a short time.

Effects of the Invention As described above, according to the hot water boiler of the present invention,
The following effects can be obtained.

(1) The flow of hot water from the heat source to the hot water storage tank is expanded by the diffusion plate and expansion member or expansion part of the return pipe.
At the same time, the flow rate is reduced and the water flows into the hot water storage tank.
At this time, the flow direction of the hot water is downward and at a low speed, so after leaving the expanding member, the flow changes freely depending on the temperature difference with the surroundings. Therefore, in the case of high-temperature hot water, it flows to the upper part of the hot water storage tank due to a low-speed upward flow caused by a draft.

Therefore, the hot water is stratified from the top without convection or stirring in the hot water storage tank, so the amount of hot water stored can be set freely. Moreover, at the same time, heat radiation loss can be suppressed to a minimum, thereby increasing economic efficiency.

(2) Since hot water is stratified from the top of the hot water storage tank, even if the hot water runs out, hot water can be obtained in a short time.

(3) Since hot water is stratified from the top of the hot water storage tank without causing convection, the hot water temperature distribution is narrow and the hot water supply temperature is stable.

[Brief explanation of the drawing]

Figure 1 is a partial sectional view of the hot water boiler of the present invention, Figure 2 is a schematic diagram of the flow of hot water in the hot water storage tank at the start of boiling, and Figure 3 is a diagram of the flow of hot water when the expanding member also becomes hot water. This is a schematic diagram of the flow, and FIG. 4 is a sectional view of a conventional hot water boiler. 1...Hot water tank, 2...Heat source, 3...Outgoing pipe, 4...
...Circulation pump, 5...Check valve, 6...Return pipe, 7...
...Water supply port, 8...Hot water supply port, 11...Enlarged member, 1
2...Diffusion plate.

Claims (1)

[Claims] 1 A hot water boiler in which a hot water storage tank equipped with a water supply port and a hot water supply port, an outgoing pipe, a circulation pump, a heat source, and a return pipe are connected in this order, wherein the hot water supply port is connected to the top of the hot water storage tank, and the return pipe is connected to the top of the hot water storage tank. A cylindrical expanding member connected from the top surface of the hot water storage tank toward the bottom and having a flow passage cross-sectional area larger than that of the returning pipe is provided vertically, and the expanding member faces the returning pipe and has a gap therein. A hot water boiler equipped with a diffuser plate that has a horizontal brim.