JPS592427Y2 - Hot water supply device - Google Patents

Description

[Detailed description of the invention] The present invention relates to a hot water supply device using an instantaneous water heater with a relatively small hot water storage capacity, which is equipped with a heat source such as a burner that detects the hot water temperature and automatically turns off the heat source. The purpose of this invention is to eliminate the temperature differential of supplied hot water during intermittent operation to zero or close to it, improve hot water supply or heating performance, and provide a safe hot water supply device.

Generally, it detects the hot water temperature of the boiler and automatically turns 0N-O.
In a hot water supply system whose hot water supply source is an instantaneous water heater with a relatively small hot water storage capacity and equipped with an FF-controlled burner, the hot water in the boiler will not rise if hot water is supplied above a certain flow rate, so the temperature will increase. The detector thermostat closes and the burner burns continuously, but when hot water is supplied below a certain flow rate, the temperature of the hot water in the boiler rises and the burner burns intermittently.

If the boundary flow rate between continuous combustion and intermittent combustion in the burner is defined as the critical flow rate, the characteristics of the supplied hot water temperature will be completely different above and below the critical flow rate.

In other words, Figures 3 and 4 show the relationship between the temperature of the supplied hot water and time, and the relationship between the temperature of the supplied hot water and the flow rate. In the region where the flow rate exceeds the critical flow rate X, the burner burns continuously, and the temperature of the supplied hot water decreases. The characteristics are stable at relatively low temperatures like A.

On the other hand, in a region where the flow rate is less than or equal to the critical flow rate X, the burner performs intermittent combustion, and the temperature characteristic of the supplied hot water has a relatively high temperature as shown in B and a temporally sinusoidal change cycle.

This temperature characteristic B has a temperature difference in the temperature of the supplied hot water, that is, a supplied hot water differential having a temperature difference Jθ.

As described above, instantaneous water heaters with a small storage capacity have two typical temperature characteristics of supplied hot water in the upper and lower regions of the critical flow rate of supplied hot water.

The temperature characteristics of the supplied hot water in the lower area of the critical flow rate are different from those of boilers with large hot water storage capacity.
When θ is large, usually 20 to 30° C., one cycle of the temperature difference in jθ is extremely short, about 3 minutes (see FIG. 5).

By the way, the temperature differential Jθ of the supplied hot water is determined by the amount of hot water stored in the boiler, the water inlet, the characteristics (temperature setting and differential) of the can water temperature control thermostat, the mounting position, etc.

For example, if the differential of the thermostat is made extremely small, the temperature of the supplied hot water will be
θ can also be made smaller, but if it is made too small, there is a risk that the temperature detection of the thermostat will malfunction.

In addition, the burner starts up too frequently, causing contact problems in the control system and deterioration of the durability of parts due to excessive startup.Simply reducing the thermostat differential will shorten the life of the boiler, and overall This is undesirable, and therefore the design is such that one cycle of the temperature differential of the supplied hot water must be approximately 3 degrees Celsius.

This characteristic is the hot water supply performance seen in conventional instantaneous water heaters with a small hot water storage capacity, and although there are relatively few problems when supplying hot water to a regular bath, when using it for showers etc. There's a problem.

In other words, it is desirable that the shower conditions satisfy the conditions of hot water supply temperature of 40°C ± 20°C and hot water supply flow rate of 61 to 121/min.On the other hand, if the hot water supply temperature differential lθ is 20 to 30°C, it is necessary to use a mixed tap. 1 even if used
The temperature changes from 0 to 15 degrees Celsius, which exceeds the maximum sensitivity when using a shower by ±2 degrees Celsius, and the temperature change cycle time is only about 3 minutes, so if you take a shower for about 155 minutes, it will feel hot or lukewarm. This can cause you to feel a lot of discomfort.

For example, assuming the thermostat is set to normal, the hot water storage capacity is 151, and the output is 26,000 kal/hc7).
In the case of an instantaneous boiler, 1017 m1n corresponds to the critical flow rate at room temperature, and when hot water is supplied at a rate of 107/min or more, it exhibits the supply water temperature characteristics of continuous combustion, and when hot water is supplied at a rate of 101/min or less, it exhibits intermittent combustion with lθ of 20 to 30°C. supply hot water temperature characteristics at the time.

When hot water is supplied at 51/min, hot water temperature characteristic B is shown, which is closest to a sine waveform, as shown in FIG.

The present invention focuses on the fact that the temperature characteristics of the supplied hot water during intermittent combustion in the burner exhibits alternating current waveform changes, and attempts to transform this into a characteristic that does not exhibit direct current changes as shown in Figure 5C. It is.

That is, the present invention provides an apparatus that can obtain the above-mentioned characteristic C in which the temperature change is linear by adding the supplied hot water temperature characteristic B' which is delayed by ÷ period to the supplied hot water temperature characteristic B shown in FIG. 5. It is.

Examples of implementing the present invention in water heaters are shown in Figures 1 and 2 below.
This will be explained with reference to the figures.

In FIG. 1, reference numeral 1 denotes an instantaneous boiler with a small hot water storage capacity, and water is supplied through a water inlet 2 and heated by, for example, a gun-type burner (not shown), which is controlled ON-OFF by a thermostat 3. ing.

Hot water is supplied from the hot water inlet 4 of the boiler 1 to a faucet 6 via a hot water supply device 5.

As shown in FIG. 2, the hot water supply device 5 has a double structure in which an outer cylinder 8 having a different volume from the inner cylinder 7 is provided outside the inner cylinder 7. is provided with a hole 9 for diversion, and a hole 10 for mixing that conducts between the inner and outer shells 7°8 is provided in the inner shell downstream thereof, and the inside of the inner shell 7 is formed as a No. 1 flow path 11, The inside of the outer shell 8 is defined as a second flow path 12.

The first flow path 11 has a hot water storage amount QA, and the second flow path 12 has a hot water storage amount Q8.

Note that the first flow path 11 is provided with a contraction section 13 .

5a is a hot water mixing promotion chamber provided on the discharge side of the hot water supply device 5, that is, on the downstream side of the mixing hole 10; Second flow path 1
Promote mixing of hot water from 1 and 12.

Reference numeral 5b denotes a mixing member disposed within the promotion chamber 5a, with its flat portion facing the discharge port 5C of the hot water supply device 5.

The mixing member 5b may be composed of a simple plate material, or may be composed of a rotating device such as a propeller fan.

The difference in the amount of hot water stored in the younger brother 1 flow path 11 and the second flow path 12, that is, the capacity difference, is calculated as QB-QA=Q8. -A, QB-A
Set as follows.

In other words, in Figs. 1, 2, and 5, when the hot water supply rate at the hot water supply port 4 is 57/min, one cycle time of the supply hot water temperature characteristics during burner intermittent combustion (burner ON time and OFF time are added) time) is 3 minutes, a contraction section 13 is provided in the first flow path 11, and the first. The flow path resistance of the second flow paths 11 and 12 is made the same, and the flow path resistance of the first flow path 11 is
．． 5'/min and the second flow path 12 at 2.51/min, the first flow path 11 and the second flow path 12 flow at a rate of 2.51/min.
There is no change in the temperature characteristics of the flow path 12 during one cycle.

In this embodiment, the flow contraction section 13 is provided to determine the amount of hot water flowing into the first and second channels 11.12, but other plates or the like may be used.

Therefore, the supply hot water temperature characteristics at the branch point A position and the confluence point mouth position in Figure 2 are the same in terms of waveform, and there is no period shift, so the waveform of the temperature characteristic is as shown in Figure 5 B. A large temperature differential appears.

Therefore, in this embodiment, QB is made larger than QA, and the first .
The purpose is to offset the differential by shifting the period of the hot water passing through the second flow paths 11 and 12 by a cycle.

Therefore, Q,−,=QBQA=2.51/minx3
minx4-X3.75 l, the second flow path 12
As shown by the broken line B' in FIG. 5, the waveform of the hot water temperature characteristic at the output donkey position is delayed in period from the waveform of the temperature characteristic B by an amount corresponding to ÷cycle.

When the waveform of the temperature characteristic B and the waveform of the temperature characteristic B' are superimposed, the flow rate of the flow path 11 and the second flow path 12 in FIG. In other words, the hot water temperature becomes constant.

That is, the temperature differential jθ of the supplied hot water is adjusted to 0 at the mixing hole 10.

Then, hot water with no temperature change can be obtained from the faucet 6.

However, in reality, if the space where the hot water in both flow paths 11 and 12 mix is too small, each flow path 11
, 12, etc., the mixing is not affected properly.

Therefore, the promotion chamber 5 which has a large space for promoting hot water mixing.
If a mixing member 5b, such as a plate or a propeller fan, is provided in the promoting chamber 5a, the flow paths 11, 12
The hot water can be guided toward the outer circumference, and then the hot water can be mixed by directing the hot water from the outer circumference toward the center.

Here, the large space in the chamber 5a means a space where convection can be promoted due to the difference in specific gravity if there is a difference in specific gravity in the hot water.

That is, since the chamber 5a and the member 5b provide a space for promoting convection due to the difference in specific gravity and mixing due to countercurrent, Jθ=0.
approach.

Of course, the member 5b may be omitted, but in that case, the space in the chamber 5a will be mixed only by convection, so the member 5b
It cannot help but be considerably larger than when there is b.

Although the above description has been made regarding an embodiment in which the device of the present invention is applied to a water heater, the present invention can similarly supply hot water without a differential and provide stable heating even in the case of heating.

That is, when a heating load lower than the output of the boiler is applied to the heating device, the temperature of the hot water in the boiler increases and the burner performs intermittent combustion.

The supplied hot water temperature characteristic during intermittent combustion becomes a sine waveform with a differential Aθ, as shown by B in FIG.

Note that B// in FIG. 7 is the return temperature characteristic of hot water, and although the temperature has decreased, the temperature characteristic has a differential that is synchronized with the characteristic B described above.

Note that the time per cycle in the supply hot water temperature characteristics during intermittent combustion is the shortest when the heating load is equal to the boiler output, as shown in FIG.

That is, in Fig. 8, B1 is the time-heating load characteristic when the burner is OFF in one cycle, B2 is the time-heating load characteristic when the burner is ON in one cycle, and when the time of both characteristics is added, it becomes the characteristic of B2 shown by the solid line. Become.

Since point Y is the heating load corresponding to the boiler output, the shortest time is ÷boiler output point Y'.

From these facts, we created a supply hot water temperature characteristic obtained by dividing the supplied hot water temperature characteristic during intermittent combustion with a differential of jθ shown in Fig. 7 by shifting the period, and by mixing the supplied hot water with both characteristics, hot water with a differential of 0 was created. This can be cycled as .

FIG. 6 shows an example of a heating device implementing the above invention,
In the figure, 14 is a boiler, and a thermostat 15
It is heated by, for example, a gun-type burner (not shown) which is ON-OFF controlled by the heater.

The hot water from the boiler 14 is passed from the hot water outlet 16 through the circulation pump 17, through the hot water supply device 18 having the first circuit and the second circuit shown in FIG. The hot water returns to the hot water return port 22 of the boiler 14 via a heating return circuit 21.

Water is supplied to the boiler 14 from the water supply port 23 through a gas tank 24 and a water supply pipe 25, and the expansion water of the boiler 14 is returned to the gas tank 24 via an expansion pipe 26. An overflow pipe 27 is provided.

In the above configuration, if the first flow path and the second flow path of the hot water supply device 18 are made to have a difference in hot water storage amount as in the case of the water heater described above, and the circulation rate of the system is set to 101/min, the burner is switched on and off. One cycle time of the supply hot water temperature characteristics during combustion is 4 minutes, and the first flow path and the second flow path are each 51/m.
In addition, the difference in the amount of hot water stored in both channels is 57'/
As m1nx4 m1nx4-10 l, it is possible to obtain the supply hot water temperature characteristic ÷ cycle equivalent flow rate ÷ period delayed supply hot water temperature characteristic, and by superimposing this on the supply hot water temperature characteristic during the original intermittent combustion, differential lθ = 0
By circulating hot water, stable heating can be achieved at all times.

In the case of heating as described above, a hot water mixing promotion chamber is provided on the discharge side of the hot water supply device 18, and the first. The hot water coming out of the second flow path can be mixed more uniformly, and the temperature of the circulating hot water can be more reliably maintained.

In addition to setting the temperature differential Jθ of hot water for hot water supply and heating to 0, the device of the present invention has the effect of increasing safety when hot water is tapped.

That is, since a general instantaneous water heater is a water heater with a high output and a small amount of hot water storage, the rate of rise of water in the can in the water heater is high, often reaching 30 degrees per minute.

In such water heaters, if the set temperature of the thermostat for controlling the burner is set to around 70°C, the temperature detection of the can water by the thermostat may not be able to follow the rate of increase in the water temperature of the water heater can, and the thermostat may not operate properly. Due to the delay in heat transfer of the high temperature gas remaining inside the combustion chamber of the latter housing through the combustion chamber wall surface, the temperature of the can water may rise and approach a boiling state.

On the other hand, if the set temperature of the thermostat is set low, there is a drawback that the temperature at which the hot water falls after tapping becomes too low.

Figure 9 shows the temperature characteristics, and the hot water temperature characteristic of a general instantaneous boiler shown by characteristic curve E is the temperature at boiling (
Starting temperature of hot water) As time passes from point a, the temperature drops as shown at point b.

For example, if you use a bath and the water in the bathtub becomes lukewarm and you add warm water to raise the temperature of the water in the bathtub, it will be difficult to raise the temperature in the bathtub again if the temperature drops to low. However, there is a drawback that the hot water does not get hot again when the hot water supply to the bathtub is actually used.

In addition, the thermostat temperature is set at around 60℃ to prevent boiling at the time of boiling and to prevent the temperature from dropping to low.
Furthermore, even if the arrangement of the water supply and hot water supply piping is taken into consideration, there is a drawback that hot water of around 90°C comes out when the hot water starts, which poses a risk of burns.

In contrast, in the present invention, even if water at 90°C is boiled in the boiler 1 in the configuration shown in Figs. 1 and 2,
In order to prevent the hot water in the first flow path 11 and the second flow path 12 from rising due to convection with the casing in the boiler 1, the diameter of the branch part of the hot water supply port 4 is made small, for example. If the hot water in the flow path 11 and the second flow path 12 is set to rise only to around 40 degrees Celsius, the temperature will rise from the hot water supply port 4 to 9.
Even when hot water at 0°C begins to flow, it is mixed with the hot water of around 40°C in the first flow path 11 and the second flow path 12, and the hot water temperature gradually rises to around 50°C as shown in the temperature characteristics shown in Figure 9C. This allows for safe hot water to be drawn without sagging.

In addition, in the temperature characteristic C in FIG. 9, the temperature drops once during the rise in the first flow path 11 and the second flow path 1.
This is because a mixing delay occurs due to the difference in capacity between the two.

The device of the present invention has the following effects due to the above-described configuration and operation.

(1) Even if the boiler is not a boiler with a large amount of hot water storage, by simply attaching a hot water supply device of about 31 to the hot water outlet to an instantaneous boiler with a small amount of hot water storage and an 0N-OFF burner without proportional control, it is possible to It is possible to provide stability in the temperature characteristics of the supplied hot water without any differentials due to height differences.

(2) Since the temperature differential during hot water supply is set to 0, there is no discomfort when using the shower.

(3) When installed at the hot water inlet of a heating circuit, the temperature flowing out of the heating circuit remains uniform and does not change.With a convection type fan convector, there is no change in the temperature of the hot air, making it possible to provide high-grade heating and at the same time provide floor heating. When used on the floor, temperature changes do not occur on the floor surface, so the heating effect is doubled.

(4) Since repeated thermal stress due to hot water temperature differences is not applied to hot water supply or heating piping, damage to piping materials due to repeated thermal stress can be prevented.

(5) Since the hot water supply device is small, with only about 31 boilers, a boiler including a hot water supply device has a much greater cost advantage than a boiler with a large hot water storage capacity.

(6) It is possible to prevent high-temperature hot water at the start of hot water dispensing and to prevent the temperature from dropping during hot water supply, which improves safety and allows smooth heating during reheating hot water supply when used in a bathtub or the like.

(7) Since the hot water supply device is composed of double cylinders, the hot water supply device is compact and has a simple structure, making it easy to install. is heat exchanged, so the heat exchange has the effect of reducing Jθ.

(8) The warm water mixing promotion chamber eliminates uneven mixing of hot water, and Jθ can be reliably maintained at 20 by convection due to the difference in specific gravity and, if necessary, mixing by counterflow.

In the above embodiment, only the case of a combined boiler was explained, but it is possible to obtain the same effect by incorporating the device of the present invention in a two-can boiler with a built-in heat exchanger for hot water supply. Needless to say.

Further, the boiler heat source may be gas, kerosene, electricity, or the like.

Furthermore, if the hot water supply outlet is subdivided into two or more branches, the temperature differential Jθ=
It is possible to achieve a performance of 0.

[Brief explanation of the drawing]

Figure 1 is a block diagram of a hot water supply system implementing the present invention, Figure 2 is a cross-sectional view of the same hot water supply system, Figures 3 and 4 are temperature characteristics of hot water supplied to an instantaneous boiler, and Figure 5 is the same A detailed explanatory diagram of supply hot water temperature characteristics, Figure 6 is a configuration diagram of a heating device implementing the present invention, Figure 7 is a diagram of hot water temperature characteristics during heating, Figure 8 is a diagram of 0N-OFF cycle-heating load characteristics, FIG. 9 is a diagram showing the outlet temperature characteristics. 1...Boiler, 4...Hot water inlet, 5.
...Hot water supply device, 7...Inner shell, 8...
... Outer body, 9 ... Diversion hole, 10 ...
・Mixing hole, 11...First channel, 12...
...Second channel, 5a...Hot water mixing promotion chamber.

Claims (1)

[Scope of utility model registration request] The boiler heat source turns 0N-OFF at the hot water set temperature.
An instantaneous water heater with a small controlled hot water storage capacity is used as a hot water supply source, and a hot water supply is connected to the hot water supply path from this hot water supply source, and the hot water supply is connected to the outside of the inner shell and connected to the inner shell. It is composed of a double cylinder with outer shells having different volumes, and the hot water supply source side of the inner shell is connected to the inner and outer shells, and the hot water flowing into one of these inner and outer shells is connected to the hot water supply source side of the inner shell. A diversion hole that divides the water into the other, and a mixing hole that connects the inner and outer shells to the inner shell downstream of this hole, and allows hot water flowing into one of these inner and outer shells to flow into the other and mix. Shape the hole for the purpose,
The hot water that has entered the hot water supply device is configured to be divided into the inner and outer shells through the above-mentioned diversion holes, mixed in the above-mentioned mixing holes, and then flowed out downstream of the mixing holes. A hot water supply device provided with a hot water mixing promotion chamber in which a hot water mixing member is arranged downstream of the mixing hole.