JPH02219947A - Instantaneous hot water feeder - Google Patents

Abstract

PURPOSE:To enable applied water to be used as hot water of a desired temperature within a short period of time after starting feeding water by a method wherein a first water feeding passage passing through a stored hot water temperature keeping container and a second water feeding passage bypassing the hot water storing temperature keeping container are arranged at a downstream side of a heat exchanger and then a pump and a valve are arranged at a downstream side of the hot water storing temperature keeping container and an up-stream side of the heat exchanger. CONSTITUTION:When a pump 6 is operated while a hot water is not being fed, water within a water feeding system 2 enters from a branched position S into a flow returning system 7, passes through a pump 6 and a check valve 8, reaches a flow merging location J with a water feeding system 2. Then, the water enters the water feeding system 2 and flows in a heat exchanger 1, thereafter the water passes through a first water feeding passage 4 and a second water feeding passage 5, returns again to the branched location S and is circulated. Accordingly, a burner 11 is properly ignited simultaneously with such a circulation as above, resulting in that the temperature of the circulating water can be increased and the hot water of which temperature is increased up to a predetermined temperature can be stored in the hot water storing temperature keeping container 3. If the hot water is fed out under a stopped condition of operation of the pump 6, the water is fed to the first and second water passing passages 4 and 5 and the water and hot water are mixed to each other in the passages 4 and 5 and the mixed water is fed out through the hot water discharging port 10. Accordingly, the remaining cold water is not be discharged at its present temperature.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to an instantaneous water heater.

(Prior art) For example, in a conventional ordinary instantaneous water heater as shown in Fig. 6, water is started to flow by opening the faucet at outlet a, and the water flow is started by opening the faucet at outlet a. When the water flow switch or flow rate sensor C detects water flowing above a predetermined level, the burner d starts combustion and heats the heat exchanger e, and the hot water thus heated in the heat exchanger e passes through the water flow system. The hot water reaches the hot water outlet a, and the hot water is drawn from here. Note that the symbols r and r' are temperature detection means such as thermistors, g is a check valve, and h is a flow rate regulating valve.

(Problem to be Solved by the Invention) In this way, in the conventional instantaneous water heater, after water flow is started and water flow exceeding a predetermined level is detected, the burner d starts combustion and the heat exchanger e starts heating. Therefore, immediately after the start of water flow, residual water in the water flow system that has not been heated at all is discharged, and then gradually heated hot water is discharged. Therefore, as shown by the broken line in FIG. 5, it takes a relatively long time, for example, a predetermined time tl, for example, 10-odd seconds, from the start of water flow until hot water at the desired working temperature is obtained.

The present invention aims to solve this problem.

(Means for Solving the Problems) The configuration of the present invention will be explained with reference to FIGS. 1 to 5 corresponding to embodiments. First, the instant water heater according to claim 1 includes: In a water passage system 2 passing through a heat exchanger 1 of a water heater, a first water passage route 4 passing through a hot water storage heat insulating container 3 is provided on the downstream side of the heat exchanger 1, and a first water flow path 4 passing through a hot water storage heat insulating container 3 bypasses the hot water storage heat insulating container 3. In addition, a reflux system 7 is configured in which a pump 6 is provided downstream of the hot water storage and heat insulating container 3 and upstream of the heat exchanger 1, and a second water flow path 5 is provided at an appropriate location in the reflux system 7. A valve 8 is provided.

Further, the instantaneous water heater described in item 2 has a heat exchanger 1 of the water heater.
In the water flow system 2 passing through, on the downstream side of the heat exchanger 1,
A first water flow path 4 passing through the hot water storage and heat insulating container 3 and a second water flow path 5 that bypasses the hot water storage and heat insulating container 3 are configured, and the first and second water flow paths 4.5 are arranged at a flow rate ratio. The water flow is controlled by a regulating means 9, and a reflux system 7 is constructed in which a pump 6 is installed downstream of the hot water storage and heat insulating container 3 and upstream of the heat exchanger 3, and A valve 8 is provided. Valve δ (51° at stop +'4*t (Operation and Examples) Next, the operation of the present invention will be explained with reference to the illustrated embodiments.

First, in the instantaneous water heater of the present invention shown in FIG. 1, when the tap 10 is closed and hot water is not being tapped,
When the pump 6 is operated, the water in the water system 2 flows as shown in Fig. 1 (
As shown by the double-dashed chain line arrow in al, it enters the reflux system 7 from the branch position is, passes through the pump 6 and the check valve 8, reaches the confluence position j with the water system 2, and enters the water system 2 from here. After flowing through the heat exchanger 1, the first. The water passes through the second water passages 4 and 5, returns to the branch position MS, and circulates. Therefore, by firing the burner 11 appropriately at the same time as the circulation, the temperature of the circulating water can be raised, and thus hot water heated to a predetermined temperature can be stored in the hot water storage and heat insulating container 3.

When the hot water outlet 10 is opened and the pump 6 starts dispensing hot water while the operation is stopped, both the first and second water passages 4.5 enter the water passage state, and as shown in FIG. 1(b), As shown by the two-dot chain line, the hot water in these paths 4.degree. 5 is mixed and discharged from the outlet 10.

Further, when a water flow switch (not shown) or the like detects water flowing through the water system 2 due to the start of hot water dispensing, the burner 11 starts combustion and the temperature in the heat exchanger 1 starts to rise. In this way, the hot water starts to be tapped, the burner 11 starts combustion, and then the heating in the heat exchanger 1 starts, until the hot water heated to a predetermined temperature is discharged from the tap 10. In this case, the residual water in the water passage system 2 is discharged, but as described above, this residual water mixes with the hot water stored in the hot water storage and insulation container 3 of the first water passage route 4. Since the water is discharged, the cold residual water is not discharged at the same temperature. Therefore, the first. By appropriately setting the flow rate ratio of the second water flow path 4.5 and the amount and temperature of hot water stored in the hot water storage and heat insulating container 3, the above-mentioned first. second water flow route 4,
By mixing the hot water in step 5, it is possible to obtain hot water at a predetermined temperature or a temperature close to the predetermined temperature suitable for normal use.

In this way, in the present invention, when the tap water outlet 10 is opened to start tap water, the remaining water is discharged for a short time until it mixes with the hot water in the hot water storage and heat insulating container 3, but after that, the water is discharged by mixing. Since the obtained hot water is discharged, hot water at a predetermined temperature or a temperature close to it can be used within a short time t. In particular, in the present invention, the hot water in the hot water storage and heat insulating container 3 is not discharged as it is, but is mixed with other residual water and discharged, so hot water at a temperature higher than the normal usage temperature can be stored. Therefore, the hot water storage and heat insulating container 3 can be downsized.

As described above, after a predetermined period of time has elapsed since the start of hot water dispensing, hot water heated to a desired temperature in the heat exchanger 1 can be used.

In the state in which hot water is being supplied as described above, if the combustion amount of the burner 11 is adjusted by changing the set value of the hot water temperature using the hot water temperature setting device, the first. When the flow rate ratio of the second water passage route 4.5 is fixed and water is always being supplied to the first water passage route 4 at a predetermined rate, the hot water storage heat insulating container 3 becomes a time delay element. , it is toward 1, where the opening time becomes longer until hot water at the desired temperature set by the hot water temperature setting device is obtained from the tap 10.

On the other hand, the configuration shown in FIG. The flow rate ratio of the second water flow path 4.5 can be adjusted by the flow rate ratio adjustment valve 9. operating the ratio adjusting means 9 to reduce the flow rate ratio of the first water flow path 4;
or zero, and as shown by the double-dashed chain arrow in FIG. can be shortened to

In addition, in the configuration shown in FIG. 2, during the above-mentioned circulation when hot water is stopped, the flow rate ratio III node means 9 is operated to perform circulation as shown by the two-dot chain arrow in FIG. 2 (al). By allowing all or most of the hot water to flow through the first water flow path 4, the temperature of the hot water in the hot water storage heat insulating container 3 can be efficiently raised. By appropriately adjusting the flow rate ratio of the water paths 4 and 5, the hot water supply characteristics at the start of hot water supply can also be adjusted.

Next, a specific configuration and control example related to the above will be explained. First, the control of the burner 11 during the hot water tapping described above can be performed as appropriate in the same manner as in the past. For example, in the water flow system 2, the temperature sensor 12, 13 such as a thermistor provided on the upstream side and the downstream side of the heat exchanger 1, the flow rate sensor 14, the hot water temperature setting device (not shown), etc. The supply of fuel to the burner 11 can be adjusted by feedforward control or feedback control to obtain hot water at a desired set temperature.

The operation control of the pump 6 described above and the combustion amount/control of the burner 11 during operation of the pump 6 can be performed, for example, by the following method. The first method is to monitor the temperature of the hot water in the hot water storage container 3, and when the temperature at that point falls below a predetermined temperature, the pump 6 is operated and the burner 11 is controlled to burn. This method raises the temperature of the hot water to a predetermined temperature. In this method, the temperature of the hot water in the hot water storage container 3 can be monitored by installing a temperature sensor inside the hot water storage container 3 and directly monitoring the hot water temperature.
It can also be indirectly monitored by a temperature sensor 13 provided between the heat exchanger 1 and the heat exchanger 1. Next, the second method operates the pump 6 at predetermined time intervals, detects the temperature of the circulating water under such operating conditions, and controls the combustion of the burner 11 when the temperature of the water is below a predetermined temperature. In this method, the temperature of the circulating hot water and the temperature of the hot water in the hot water storage heat insulating container 3 are raised to a predetermined temperature. In this method, the temperature of the hot water can be detected using temperature sensors 12, 13, etc. installed at appropriate locations in the circulation path.

As described above, the flow rate ratio adjusting means 9 adjusts the flow rate ratio to the first rate in response to the operation from the start of hot water dispensing until a predetermined time has elapsed. Water can flow through the second water flow path 4.5 at a predetermined flow rate, and the first
The flow rate of the water flow route 4 is made small or zero, and the second
If the configuration is such that most or all of the water can flow through the first water passage 5, an on-off valve may be provided in the first water passage 4, in addition to the embodiments shown in FIGS. 3 and 4, for example. The configuration, etc., is appropriate. The configurations shown in FIGS. 3 and 4 are respectively 1. A flow path U corresponding to the second water flow path 4.5.

A rotating valve body 15 is provided between the common flow path W and the valve body 15, and the valve body 15 is rotated by a motor 16 so that the direction in which the flow path U is closed is the direction in which the flow path V is opened. They are arranged freely. In such a configuration, FIG. Second
Figure 4 (
bl represents a state in which the flow rate flowing through the first water flow path 4 is smaller than the flow rate flowing through the second water flow path 5.

In such a configuration, the valve body 15 and each flow path U.

By appropriately designing the shapes of v and w, it is possible to easily configure the total flow rate so that it does not change even if the flow rate ratio is changed.

In the illustrated embodiment, reference numeral 17 indicates a water supply port connected to a water supply, etc., 18 indicates a check valve, and 19 indicates a flow rate of hot water, giving priority to the set temperature when the hot water load exceeds the capacity of the bar 11. This is a flow rate adjustment valve for dispensing hot water at a reduced rate.

(Effects of the Invention) As described above, the present invention provides, in a water flow system passing through a heat exchanger of a water heater, a hot water storage and heat insulating container on the downstream side of the heat exchanger, and a hot water storage and heat insulating container on the downstream side of the hot water storage and heat insulating container. A reflux system is configured with a pump provided on the upstream side of the heat exchanger, and when hot water is not being tapped, a burner for heating the heat exchanger is combusted while circulating hot water through the reflux system and the water flow system. Since the hot water in the hot water storage thermal container is heated to a predetermined temperature and stored, once the hot water outlet is opened and water starts flowing, hot water at or close to the desired temperature can be used within a short period of time. There is an effect that it can be done. Further, the present invention has the effect that an auxiliary heating source such as an electric heater is not required because the temperature of the hot water in the hot water storage container is raised by the burner used for raising the temperature during normal hot water dispensing.

Furthermore, the present invention configures a water passage that bypasses the hot water storage and insulation container in parallel with the water passage that passes through the hot water storage and insulation container,
Since the hot water in these water flow paths is mixed and discharged from the hot water outlet, hot water at a temperature higher than the normal operating temperature can be stored in the hot water storage container, which makes it possible to downsize the hot water storage container. This also has the effect of shortening the delay time in changing the setting of the hot water tap temperature.Furthermore, the present invention has the effect of shortening the delay time when changing the setting of the tap water temperature. By configuring all or most of the flowing hot water to flow through the bypass water flow path, there is an effect that the delay time in changing the setting of the hot water temperature can be further shortened.

[Brief explanation of the drawing]

Figure 1 (a), (bl and Figure 2 (a), (b),
(c) is a system explanatory diagram showing the overall configuration and operation of the embodiment of the present invention, FIG. FIG. 3 is an explanatory cross-sectional view taken along the line X-X in FIG. 3 showing the operation of the M adjustment means, FIG. 5 is an explanatory view showing the hot water output characteristics of the present invention and the conventional example, and FIG. 6 is an explanatory diagram of the system of the conventional example. . Reference numeral 1: heat exchanger, 2: water flow system, 3: hot water storage heat insulating container, 4: first water flow route, 5: second water flow route, 6...・Pump, 7... Reflux system, 8...
・Valve, 9... Flow ratio adjustment means, 10... Tap water outlet,
11...Burner, 12.13...Temperature sensor, 14
...Flow rate sensor, 15...Valve body, 16...Motor, 17...Water supply port, 18...Check valve, 19...Flow Ill regulating valve. Figure 1 (a) Figure 1 (b) Figure I2 (C) Figure 2 (a) Figure 1

Claims (6)

[Claims] (1) In a water passage system that passes through a heat exchanger of a water heater, there is a first water passage route that passes through a hot water storage and insulation container on the downstream side of the heat exchanger, and a second water passage that bypasses the hot water storage and insulation container. In addition to configuring a water flow path, a reflux system is configured with a pump provided downstream of the hot water storage and heat insulating container and upstream of the heat exchanger, and a valve is provided at an appropriate position in the reflux system. Instant water heater. (2) In a water passage system that passes through a heat exchanger of a water heater, there is a first water passage route that passes through a hot water storage and insulation container on the downstream side of the heat exchanger, and a second water passage that bypasses the hot water storage and insulation container. The first and second water passages are configured to have water passage controlled by a flow rate ratio adjusting means, and a pump is provided downstream of the hot water storage and heat insulating container and upstream of the heat exchanger. 1. An instantaneous water heater comprising a reflux system including a reflux system, and a valve provided at an appropriate position in the reflux system. (3) The instantaneous water heater according to item 1 or 2, wherein the hot water storage container stores hot water at a temperature higher than the normal operating temperature. (4) The instantaneous water heater according to item 1 or 2, wherein the valve included in the reflux system is a check valve. (5) In the water heater described in paragraph 1 or 2, when hot water is not being discharged from the hot water outlet, the pump and the burner for heating the heat exchanger are controlled by monitoring the temperature of the hot water in the hot water storage insulating container. An instantaneous water heater characterized in that the water temperature in the hot water storage heat insulating container is raised to a predetermined temperature. (6) In the water heater described in paragraph 1 or 2, when hot water is not being discharged from the tap, the pump is operated at predetermined intervals, and the circulating hot water is An instantaneous water heater characterized by increasing the temperature of hot water in a hot water storage heat insulating container to a predetermined temperature by detecting the temperature and controlling a burner.