JP3081276B2 - Water heater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001] The present invention relates to a water heater capable of preventing a decrease in hot water temperature at the time of re-starting hot water after one stop.

[0002]

2. Description of the Related Art Conventionally, as a general type of water heater, FIG.
There is a water heater B shown in FIG.

[0003] As shown in the figure, a water heater B is provided with a water supply pipe 50.
Is connected to the inlet 52 of the heat exchanger 51,
The upstream end of a hot water supply pipe 54 is connected to an outlet 53 of the heat exchanger 51. Further, a water amount sensor 55 and a temperature sensor 56 are attached to the water supply pipe 50, and a temperature sensor is mounted to the hot water supply pipe 54.
57 and a water quantity valve 58 are attached.

[0004] With this configuration, the water flowing into the heat exchanger 51 from the water supply pipe 50 is heated and turned into hot water.
The hot water is supplied to a desired tapping point.

[0005]

However, in the above-described water heater B, when the shower is used, the hot water supply is stopped for a short time.
When so-called one-stop re-watering is performed, as shown in FIG. 5, the water-volume valve 58 is opened, and the temperature of the hot-water supply drops sharply temporarily, causing discomfort to the shower user. Had become.

It is an object of the present invention to provide a water heater with improved re-watering performance capable of solving the above-mentioned problems.

[0007]

According to the present invention, a first solenoid valve is attached to a water supply pipe on the inlet side of a main heat exchanger, and a sub heat exchanger is installed so as to bypass the first solenoid valve. Connect a bypass pipe to the water supply pipe, attach a flow control valve to the sub heat exchanger, and connect a bypass pipe bypassing the flow control valve to the sub heat exchanger. The present invention relates to a water heater having a second solenoid valve mounted thereon.

[0008] Further, the present invention provides a method for re-watering after stopping hot water supply,
Closing the first solenoid valve and opening the second solenoid valve to allow the sub heat exchanger in the heat storage state to communicate with the heat exchanger; normally, at the time of tapping, open the first solenoid valve and close the second solenoid valve; Water is mainly supplied through the first solenoid valve, and part of the water is supplied through the flow control valve of the sub heat exchanger. The sub heat exchanger is a drum wound around the main heat exchanger. A pipe, and furthermore, on the path of the water supply pipe, a point on the upstream side of the sub heat exchanger and a hot water supply pipe connected to the outlet of the main heat exchanger are connected by a hot / water mixing bypass pipe. It is also characterized in that a hot / water mixing valve is provided at the connection between the hot / water mixing bypass pipe and the hot water supply pipe.

[0009]

According to the present invention, during normal operation, the first solenoid valve is opened and the second solenoid valve is closed, a large amount of water is supplied to the heat exchanger from the water supply pipe, and the flow control valve is supplied from the drum pipe in the heat storage state. A small amount of heated water controlled by the above is supplied to the heat exchanger.

When the hot water is re-discharged after the one-stop operation, the first solenoid valve is closed and the second solenoid valve is opened to shut off the water supply from the water supply pipe to the heat exchanger. The internal water can be supplied to the heat exchanger through a bypass pipe. At this time, the heated water in the drum pipe can be supplied to the heat exchanger without being throttled by the flow control valve, so that a large amount of heated water can be supplied to the heat exchanger. Hot water at a suitable temperature can be discharged without lowering the temperature. Therefore, a shower user or the like can enjoy a shower or the like without feeling discomfort due to a sudden change in tapping temperature.

Further, even during normal operation, a small amount of heated water is supplied to the heat exchanger from the drum pipe, so that various troubles caused by water remaining in the drum pipe and boiling can be prevented. it can.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a water heater according to an embodiment of the present invention;

(Embodiment 1) As shown in FIG. 1, a water heater A according to the present embodiment connects a downstream end of a water supply pipe 10 to an inlet 12 of a heat exchanger 11, and The upstream end of the hot water supply pipe 14 is connected to the outflow port 13.

A water flow sensor 15 is attached to the water supply pipe 10, and a temperature sensor 17 and a water flow valve are mounted to the hot water supply pipe 14.
18 and are installed.

With this configuration, the water flowing from the water supply pipe 10 into the heat exchanger 11 is heated to become hot water,
The hot water is supplied to a desired tapping point.

Further, in the present embodiment, a drum pipe 20 as a sub heat exchanger is arranged in the middle of the water supply pipe 10, and the upstream and downstream ends of the drum pipe 20 are provided in the middle of the water supply pipe 10. The first solenoid valve 16 is connected to the upstream and downstream sides.

The drum pipe 20 is wound around the outer peripheral surface of the casing of the heat exchanger 11 in order to improve the heat storage efficiency.
As will be described later, always heated by the heat exchanger 11,
It is configured to be in a heat storage state.

The drum pipe 20 is provided with a flow control valve 21 in the middle thereof, and a portion on the upstream / downstream side of the flow control valve 21 is provided with a bypass pipe 22 juxtaposed to the drum pipe 20. The downstream end is connected.

Further, a second solenoid valve 23 is connected to the bypass pipe 22.
Is installed.

By opening and closing the first solenoid valve 16, water can be supplied to the heat exchanger 11 through the water supply pipe 10 and water can be stopped.

Further, by the closing operation of the second solenoid valve 23, a small amount of water controlled through the flow regulating valve 21 provided on the drum pipe 20 in the heat storage state can be supplied to the heat exchanger 11. By the opening operation of the second solenoid valve 23, a large amount of heated water can be supplied to the heat exchanger 11 through the bypass pipe 22.

In FIG. 1, reference numeral 30 denotes a control device, and an input interface of the control device 30 has a water flow sensor 15
And a temperature sensor 17 and the like, while a first solenoid valve 16, a second solenoid valve 23, and a water quantity valve 18 are connected to the output side interface.

Next, the control of tapping operation by the water heater A having the above configuration will be described with reference to a timing chart shown in FIG.

In the figure, indicates the outlet temperature of the heat exchanger 11, that is, the tap water temperature, indicates the outlet temperature of the drum pipe 20, indicates the inlet temperature of the heat exchanger 11, and indicates the temperature of the heat exchanger 11. Indicates the mixing ratio of the water supply pipe-side water supply and the drum pipe-side water supply of the supply water flowing into the tank, indicates the opening and closing operation of the first solenoid valve 16, and indicates the opening and closing operation of the second solenoid valve 23.

As shown, during normal operation, the first solenoid valve 16 is open and the second solenoid valve 23 is closed.

Therefore, the mixing ratio a: b is supplied to the heat exchanger 11.
, A large amount of water at a normal temperature is supplied through a water supply pipe 10, while a flow control valve 21 is supplied through a drum pipe 20.
A small amount of heated water squeezed in is supplied.

As described above, during normal operation, the water flowing in the drum pipe 20 is heated by the heat from the heat exchanger 11, but does not stay in the pipe, so that it does not boil. It is possible to prevent a problem caused by boiling, for example, an excessively high temperature of the hot water from the heat exchanger 11.

By the way, since the diameter of the drum pipe 20 and the bypass pipe 22 are the same as the diameter of the water supply pipe 10, a large amount of warming water is supplied to the heat exchanger 11 from the drum pipe 20. Therefore, as shown in FIG. 2, even when the hot water is re-started after one stop, the hot-water outlet temperature, which is the outlet temperature of the heat exchanger 11, can be restarted almost without lowering. That is, the tapping temperature hardly changes, and even when tapping again after one-stop, the high-temperature state can be maintained, and the user does not feel uncomfortable when using a shower or the like.

(Embodiment 2) The present embodiment is characterized in that the water heater A described in Embodiment 1 is further provided with a hot water mixing function.

That is, as shown in FIG. 3, the hot water supply device A is provided with a bypass pipe for hot and cold water mixing between a location of the water supply pipe 10 on the upstream side of the upstream end of the drum pipe 10 and a middle of the hot water supply pipe 14.
In addition to the provision of the hot water mixing tap 41, the hot water mixing tap 41 is attached to the connection between the bypass pipe 40 and the hot water supply pipe 14.

With this configuration, it is possible to improve the tapping performance at the time of tapping again as described in the first embodiment, and to control the hot water tapping from the heat exchanger 11 by controlling the drive of the tap mixer 41. And water at a normal temperature is mixed at an appropriate mixing ratio to easily obtain a mixed hot water at a desired temperature.

[0032]

As described above, according to the present invention, the first solenoid valve is attached to the water supply pipe on the inlet side of the main heat exchanger,
The auxiliary heat exchanger is connected to the water supply pipe in a bypass manner so as to bypass the first solenoid valve, and a flow control valve is attached to the auxiliary heat exchanger, and a bypass that bypasses the flow control valve is provided. The pipe is connected to the sub heat exchanger, and a second solenoid valve is attached to the bypass pipe. Then, at the time of hot water re-discharge after the stop of hot water supply, the first electromagnetic valve is closed and the second electromagnetic valve is opened to connect the sub heat exchanger in the heat storage state and the heat exchanger. A large amount of water can be supplied to the main heat exchanger without squeezing the heated water of the main heat exchanger. You can take a hot spring. Therefore, a shower user or the like can enjoy a shower without feeling discomfort due to a sudden change in tap water temperature. In particular, by making the sub heat exchanger a drum pipe wound around the main heat exchanger, the heat storage effect can be enhanced with a simple configuration.

During normal tapping, the first solenoid valve is opened and the second solenoid valve is closed, and water is supplied mainly through the first solenoid valve, and partly through the flow regulating valve of the sub heat exchanger. Since the water is supplied, it is possible to prevent various troubles caused by the water remaining in the sub heat exchanger and boiling.

Further, a location on the water supply pipe route, which is on the upstream side of the sub heat exchanger, and a hot water supply pipe connected to the outlet of the main heat exchanger are connected by a hot / water mixing bypass pipe. By providing a hot-water mixing valve at the connection between the hot-water mixing bypass pipe and the hot-water supply pipe, it is possible to mix the normal-temperature water into the high-temperature hot water discharged from the heat exchanger through the hot-water mixing bypass pipe at an appropriate mixing ratio. And mixed water at a desired temperature can be easily obtained.

[Brief description of the drawings]

FIG. 1 is a conceptual configuration diagram of a water heater according to Embodiment 1 of the present invention.

FIG. 2 is a timing chart showing a temperature change in each part of the water heater.

FIG. 3 is a conceptual configuration diagram of a water heater according to a second embodiment of the present invention.

FIG. 4 is a conceptual configuration diagram of a conventional water heater.

FIG. 5 is a graph showing a temperature change of a tapping temperature of the water heater.

[Explanation of symbols]

 A Water heater 10 Water supply pipe 11 Heat exchanger 12 Inlet 13 Outlet 14 Hot water supply pipe 16 First solenoid valve 20 Drum pipe 23 Second solenoid valve

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-366325 (JP, A) JP-A-2-150631 (JP, A) Japanese Utility Model Showa 60-37734 (JP, U) (58) Field (Int.Cl. ⁷ , DB name) F24D 17/00 F24H 1/10 302

Claims (5)

(57) [Claims] 1. A water supply pipe on an inlet side of a main heat exchanger.
Attach the first solenoid valve to and bypass the first solenoid valve
At the same time, connect the auxiliary heat exchanger to the water supply piping in a bypass
In addition, a flow control valve is attached to the sub heat exchanger,
Piping bypass piping bypassing the flow control valve to the sub heat exchanger
With connecting, hot water supply unit characterized in that attaching the second solenoid valve in the bypass pipe. 2. The first solenoid valve is closed at the time of tapping again after stopping tapping.
Then, the second solenoid valve is opened, and the sub heat exchanger in the heat storage state and the heat
2. The communication device according to claim 1, wherein the communication device is connected to an exchange.
Water heater. 3. During normal tapping, the first solenoid valve is opened and the second solenoid valve is opened.
When the solenoid valve is closed and water is supplied mainly through the first solenoid valve
In both cases, part of the water is supplied via the flow control valve of the sub heat exchanger.
The water heater according to claim 1, characterized in that: 4. The auxiliary heat exchanger is provided around a main heat exchanger.
A drum pipe wound around
The water heater according to any one of claims 1 to 3. 5. A sub heat exchanger on a feed water pipe route.
And the outlet of the main heat exchanger.
Communicating the connection was hot water supply pipe and the bypass piping for the hot and cold water mixing the
Connection and connection of hot water mixing bypass pipe and hot water supply pipe
A hot water mixing valve is provided in the section.
The water heater according to any one of claims 1 to 4.