JPH11148718A - Water heater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water heater to suppress the increase of a temperature of supply hot water even when an amount of water supplied to a heat-exchanger is decreased during the use of supply hot water. SOLUTION: A water heater heats a heat-exchanger by a burner having a plurality of combustion surfaces. The water heater comprises a switch valve 231 to open and close at least one of a plurality of branch pipes 28 (28a and 28b) branched from a main gas supply pipe 18 to supply gas to a burner 20 and supply gas to respective combustion surfaces; and a main gas valve 191 to open and close the main gas supply pipe 18. When a flow rate higher than a first flow rate flows to a heat-exchanger 14, the main gas valve 191 is opened and when a second flow rate higher than the first flow rate flows to the heat- exchanger 14, the switch valve 231 is opened. Thus, since when a flow rate flowing to the heat-exchanger 14 is decreased to a value lower than the second flow rate, the switch valve 231 is closed, an amount of gas supplied to a burner is decreased and the increase of a supply hot water temperature is prevented from occurring.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a balanced type water heater in which combustion is performed by natural air supply and exhaust.

[0002]

2. Description of the Related Art FIG. 5 is a block diagram of a conventional balanced water heater. According to FIG. 5, when the hot water tap 10 is opened, the water
The water is supplied to a heat exchanger 14 through a water switch 12 and a water governor 13 arranged in a water supply pipe 11. Water governor 1
Reference numeral 3 denotes a pressure regulator for adjusting the primary pressure water supplied thereto to a lower secondary pressure and outputting the adjusted secondary pressure. In particular,
The water pressure of the water flowing to the secondary side is adjusted by moving the diaphragm provided inside the water governor 13 according to the difference between the primary pressure and the secondary pressure.

When the flow switch 12 detects a flow rate equal to or more than a predetermined amount (for example, 3 liters / minute), the switch 12 is turned on, thereby opening a source gas valve 19 disposed in the gas supply pipe 18 and causing the burner to open. Gas is supplied to 20.
The original gas valve 19 in FIG. 5 is an electromagnetic valve. And
Combustion starts by a predetermined ignition operation. Heat exchanger 1
The hot water heated by 4 passes through a hot water supply pipe 15 and is dropped into a bathtub 16 or used for a shower 17 or the like.

At this time, the user of the hot water supply adjusts the hot water temperature adjusting knob 2.
By manually setting 1 at a predetermined position, hot water at a predetermined set temperature is supplied. Specifically, when the hot water temperature control knob 21 is adjusted, the opening adjustment throttle 22 for adjusting the opening of the water supply pipe 11 changes, and the amount of water supplied to the heat exchanger 14 is adjusted. Thus, the water heater of FIG. 5 does not adjust the combustion amount of the burner 20, that is, the gas amount to the burner 20,
By adjusting the amount of water, the temperature of the hot water is adjusted.

On the other hand, the burner 20 has a plurality of combustion surfaces (two in FIG. 5), and branch tubes 28a and 28 branched from the gas supply pipe 18 to each of the combustion surfaces.
b are connected in parallel. Then, the branch pipes 28a and 28
At least one of the b (in the figure, a branch pipe 28b) is provided with a switching valve 23 that opens and closes it. The number of combustion surfaces of the burner 20 is not limited to two as shown, and three or more surfaces may be provided. And the branch pipe 28 is arrange | positioned according to the number of combustion surfaces.

[0006] The switching valve 23 is opened and closed by a hot water supply user switching a predetermined switching switch 24 provided outside the water heater. Thus, the changeover switch 2
4, the switching valve 23 opens and closes, and the combustion capacity of the burner 20 is switched.

The changeover switch 24 is manually switched by a hot water supply user. For example, in winter, since the supply water temperature is low, the changeover valve 23 is opened by the changeover switch 24 to burn the entire burner 20 and heat the water in the heat exchanger 14 to the set temperature. On the other hand, in summer, the supply water temperature is relatively high, so that a very high combustion capacity is not required to supply the hot water at the set temperature. Accordingly, the water in the heat exchanger 14 is sufficiently heated to the set temperature by the partial combustion of the burner 20 in which the switching valve 23 is closed by the switching switch 24. As described above, the changeover switch 24 is mainly for switching the combustion capacity according to the season and the like, and the switching stage is usually about two or three stages. , Is not generally used.

[0008]

At this time, the following hot water supply state may occur. That is, first, the switching valve 23 is opened by the switching switch 24,
The entire burner 20 is burned. At this time, when the predetermined temperature is set by adjusting the hot water temperature adjusting knob 21,
In some cases, the throttle 22 has a maximum opening degree and hot water near the maximum flow rate is supplied. In particular, the user of the hot water supply
For example, when hot water is used, hot water is supplied with a sufficient amount of hot water.

At this time, if water is used in a kitchen, a washroom, or the like, which is a connection destination of another water supply pipe 25 branched from the main water pipe of the water supply pipe 11, the pressure of the water supplied to the water heater decreases. . Then, the amount of water supplied to the heat exchanger 14 decreases in a state where the combustion amount of the burner 20 does not change, so that the hot water supply temperature increases. This gives the user of hot water discomfort and is not preferred.

In this case, the hot water temperature adjusting knob 21
The amount of water supplied to the heat exchanger 14 is set to the maximum flow rate.
It is not possible to increase the amount of water supplied to the hot water supply, and therefore, it is impossible to lower the hot water supply temperature.

On the other hand, since the changeover switch 24 is manually switched, the combustion capacity cannot be switched before the hot water supply temperature rises rapidly.

Accordingly, it is an object of the present invention to provide a water heater that suppresses an increase in hot water supply temperature even when the amount of water supplied to the heat exchanger 14 decreases during hot water supply. Is to do.

[0013]

Means for Solving the Problems In order to achieve the above object, a water heater according to the present invention has a structure in which a water heater for heating a heat exchanger by a burner is provided based on an amount of water supplied to the heat exchanger. A water heater comprising a switching valve for switching a gas supply amount to the burner.

With this configuration, when the amount of water supplied to the heat exchanger decreases, the amount of gas supplied to the burner is reduced, thereby preventing an increase in hot water supply temperature.

Further, the burner of the water heater according to the present invention has a plurality of combustion surfaces, and the switching valve branches from a source gas supply pipe for supplying gas to the burner, and a gas is supplied to each combustion surface. By opening and closing at least one of a plurality of branch pipes supplying the gas, the gas supply amount to the burner is switched. For example, the switching valve is opened when the amount of water supplied to the heat exchanger is equal to or more than a predetermined amount, and is closed when the amount of water is smaller than the predetermined amount.

Further, the water heater of the present invention is provided with a source gas valve for opening and closing the source gas supply pipe, and when the flow rate of the first flow rate or more flows through the heat exchanger, the source gas valve is opened. When a second flow rate greater than the first flow rate flows through the heat exchanger, the switching valve is opened.

Therefore, when the flow rate flowing through the heat exchanger becomes smaller than the second flow rate, the switching valve is closed, so that
The amount of gas supplied to the burner is reduced, and an increase in hot water supply temperature can be prevented.

The water heater of the present invention has a diaphragm that moves in accordance with the water pressure of the water flowing into the water heater, and the water pressure of the water that is sent out to the heat exchanger in accordance with the movement of the diaphragm. A water governor for adjusting the pressure is provided, and the source gas valve is a hydraulic automatic gas valve that opens and closes the source gas supply pipe in conjunction with movement of the diaphragm when the first flow rate flows through the heat exchanger. There is a feature.

Further, the water heater of the present invention has a flow rate detecting means for detecting a second flow rate flowing through the heat exchanger, and the switching valve includes a second flow rate detected by the flow rate detecting means. It is a solenoid valve that opens and closes according to the following.

Further, the flow rate detecting means detects the first flow rate and opens and closes a source gas valve which is an electromagnetic valve. The hydraulic automatic gas valve opens and closes the branch pipe based on the second flow rate. It may be a switching valve that performs switching. Further, it is preferable that the flow rate detecting means is a flowing water switch.

As described above, by using the flowing water switch and the automatic water pressure valve, it is possible to switch the combustion capacity with low power consumption.

[0022]

Embodiments of the present invention will be described below with reference to the drawings. However, the technical scope of the present invention is not limited to this embodiment.

FIG. 1 is a schematic configuration diagram of a water heater according to an embodiment of the present invention. According to FIG. 1, when the hot-water tap 10 is opened, water flows from the hot-water supply pipe 15 to the bathroom via the water switch 12, the water governor 13, and the heat exchanger 14, as in FIG. 5 described above.

The original gas valve 191 in the water heater according to the embodiment of the present invention is a hydraulic pressure which opens and closes the gas supply pipe 18 in conjunction with the movement of the diaphragm of the water governor 13 instead of the solenoid valve 19 in FIG. It is an automatic gas valve. When the amount of water corresponding to the first flow rate (for example, 3 liters / minute) supplied to the heat exchanger 14 flows into the water governor 13, the water pressure is automatically adjusted in conjunction with the diaphragm that is moved by the water pressure of the flowing water. Gas valve 191 is opened and burner 2
0 is supplied with gas. Then, the combustion starts by a predetermined ignition operation, and the hot water heated by the heat exchanger 14 is dropped into the bathtub 16 or the shower 1 in the bathroom.
7 and so on.

FIG. 2 shows the water governor 13 and the hydraulic automatic gas valve 1.
FIG. 9 is a diagram illustrating a configuration example of a configuration 91. According to FIG. 2, when water flows into the water governor 13, the water pressure of the diaphragm 1
Push up 31. Then, a constant flow rate of water flows out according to the positional relationship between the valve 132 and the valve seat 133 interlocked with the movement of the diaphragm 131. A part of the outflowing water is fed back to the water governor 13. Then, when the water pressure changes, the valve 132 linked with the diaphragm 131 moves, and is controlled so that the amount of water flowing out of the water governor 13 becomes constant.

More specifically, when the amount of water flowing into the water governor 13 decreases and the amount of water flowing out decreases, the pressure of the water fed back to the water governor 13 also decreases. Therefore, the diaphragm 131 moves up according to the decrease. Accordingly, the position of the valve 132 also rises, so that the water governor 1
The amount of water flowing into 3 increases, and the amount of water flowing out returns to a predetermined constant flow rate and is maintained at that flow rate. Conversely, when the amount of water flowing into the water governor 13 increases and the amount of water flowing out also increases, the pressure of the water fed back to the water governor 13 also increases. Therefore, the diaphragm 131 descends according to the increase. Accordingly, the position of the valve 132 is also lowered, and the amount of water flowing into the water governor 13 is limited, so that the amount of flowing water returns to a predetermined constant flow rate, and the flow rate is maintained.

On the other hand, the water pressure automatic gas valve 191 is connected to a diaphragm 131 by a shaft 134 from the water governor 13.
Is linked to Then, the gas supply pipe 18 is opened and closed according to the movement of the diaphragm 131 as described above. That is, before water flows into the water governor 13, the automatic hydraulic pressure gas valve 191 is at the position M. At this position M, the gas supply pipe 1
Reference numeral 8 denotes a shut-off state, and no gas is supplied to the burner 20. Then, when water flows into the water governor 13, the diaphragm 131 rises, and in conjunction therewith, the hydraulic gas automatic valve 191 also rises and reaches the position N. Then, the cutoff state of the gas supply pipe 18 is released, and the gas is supplied to the burner 20.

Returning to FIG. 1, in the embodiment of the present invention, the switching valve 231 for switching the combustion surface of the burner 20 is constituted by an electromagnetic valve which is opened and closed by an on / off signal of the flowing water switch 12. You. Specifically, when the flowing water switch 12 detects a second flow rate (for example, 8 liters / minute) larger than the first flow rate, the switching valve 231 is opened.

Therefore, in the embodiment of the present invention,
First, when water flows at a first flow rate (for example, 3 liters / minute) for starting combustion in the water governor 13, the automatic hydraulic gas valve 191 is opened, and gas is supplied to the combustion surface A of the burner 20. 20 partial combustion starts. Further, when the flowing water switch 12 detects a second flow rate (for example, 8 liters / minute) larger than the first flow rate, the switching valve 231 is opened, gas is supplied to the combustion surface B of the burner 20, and the entire surface of the burner 20 is It becomes burning.

In addition, the hot water supply temperature is adjusted by the hot water supply user adjusting the opening of the water supply pipe 11 by the hot water temperature adjusting knob 21 in the same manner as in the above-described conventional water heater, and the amount of water supplied to the heat exchanger 14 is controlled. This is done by adjusting

FIG. 3 is a diagram showing the relationship between the amount of water supplied to the heat exchanger 14 (hereinafter referred to as the amount of water supply) and the temperature of hot water supply. According to FIG. 2, when the water supply amount (3 liters / minute in the figure) exceeds the opening of the hydraulic automatic gas valve, the combustion on the combustion surface A starts. The hot water supply temperature at this time is adjusted by the hot water temperature adjusting knob 21 as described above. According to the figure, when the water supply amount is 3 liters / minute, it is, for example, 50 degrees, and as the water supply amount increases, the hot water supply temperature decreases.

When the amount of supplied water reaches, for example, 8 liters / minute, the water flow switch 12 is turned on and the switching valve 2 is turned on.
3 can be opened. When the switching valve 23 is opened, the combustion surface B
Also starts combustion, and the entire combustion is performed by the combustion surfaces A and B. At this time, the hot water supply temperature rises again because the combustion amount has increased, and is, for example, 45 degrees.

Further, as the amount of supplied water increases, the temperature of the supplied hot water gradually decreases, and at the maximum flow rate (for example, 12 liters / minute), the temperature of the supplied hot water becomes, for example, 40 degrees.

When the hot water supply user wants to use a hot water supply (for example, a shower 17) having a large flow rate of about 40 degrees when the water supply amount and the hot water supply temperature have the above-described relationship, the hot water supply amount is equal to the maximum flow rate (12 liters). / Min) (see point P in the figure).

At this time, if it is used in a kitchen or a washroom to which another water supply pipe 25 branched from a main water pipe for supplying water to the water heater, the water pressure of the water supplied to the water heater decreases. I do. Although the water pressure slightly decreases, the amount of water supplied to the heat exchanger 14 is maintained constant by the water pressure maintaining function of the water governor 13, but the water is used in a kitchen or a washroom, and the control range of the water governor 13 is controlled. Above this, the water supply will decrease significantly.

When the amount of water supplied to the heat exchanger 14 decreases, the hot water supply temperature increases. At this time, since the hot water supply user is using the hot water supply at the maximum flow rate, the hot water supply amount cannot be increased to lower the hot water supply temperature. In particular, when the amount of supplied water is significantly reduced, the temperature of supplied hot water rapidly rises, which hinders a user of the hot water supply from comfortably using the supplied hot water.

However, when the hot water supply temperature rises rapidly and the amount of water supply decreases so that the hot water supply user feels uncomfortable,
For example, when the flow rate is reduced to less than 8 liters / minute, for example, to 7 liters / minute, the flow switch 12 is turned off and the switching valve 230 is closed. Then, the gas supply to the combustion surface B is stopped, and the combustion is switched to combustion A alone.
Therefore, the hot water supply temperature is about 4
It is maintained near 0 degrees (42 degrees in the figure).

As described above, according to the embodiment of the present invention, when the amount of water supplied to the heat exchanger 14 (water supply amount) decreases, the combustion capacity is automatically reduced, so that the temperature of the hot water supply becomes sharp. Ascent can be prevented.

FIG. 4 is a schematic configuration diagram of a water heater according to a second embodiment of the present invention. In the second embodiment, the flow switch 12 detects the first flow rate for starting combustion, and opens the original gas valve 192. This source gas valve 192 is turned on / off of the water switch 12.
An electromagnetic valve that opens and closes in response to an off signal. Further, the switching valve 232 is constituted by a hydraulic automatic gas valve, and the branch pipe 28b is opened and closed in conjunction with the movement of the diaphragm 131 of the water governor 13 corresponding to the second flow rate.

As in the second embodiment, a solenoid valve 192 responsive to the flowing water switch 12 and a water pressure automatic gas valve 232 linked to the water governor 13 are used for applications opposite to those of the first embodiment. May be done.

In the embodiment of the present invention, a water flow switch 12 is used as a means for detecting a flow rate.
The automatic water pressure gas valve 191 or 232 is connected to the water governor 1.
In conjunction with the movement of the diaphragm of No. 3, it opens and closes itself according to a predetermined flow rate. In the embodiment of the present invention, the hot water supply control can be executed by a flow rate sensor that detects the amount of water supplied to the heat exchanger 14 instead of the above. However, the water heater in the embodiment of the present invention is, for example, a balanced water heater installed in a bathroom, and obtains electric power from a built-in dry battery without using commercial electric power in order to prevent danger such as electric leakage. . Therefore, a flow sensor that always requires electric power to detect the flow rate due to a demand for low power consumption is not suitable for the water heater in the embodiment of the present invention. On the other hand, the running water switch 12 consumes power only when hot water supply is performed so that the running water switch 12 is turned on, and the power consumption is small. Further, the hydraulic automatic gas valve 191 or 232 does not require electric power to operate. As described above, in the water heater according to the embodiment of the present invention, the running water switch 12 and the automatic water pressure gas valve 19 are provided.
Preferably, 1 or 232 is used.

Further, the water heater according to the embodiment of the present invention may have a reheating function for reheating the hot water in bathtub 16.

[0043]

As described above, according to the present invention,
When the amount of water supplied to the heat exchanger decreases, the combustion capacity is automatically reduced, thereby preventing a rapid rise in hot water supply temperature. Further, such combustion capacity control can be achieved with low power consumption.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a water heater according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a configuration example of a water governor 13 and a hydraulic automatic gas valve.

FIG. 3 is a diagram showing a relationship between an amount of water supplied to a heat exchanger 14 and a hot water supply temperature.

FIG. 4 is a schematic configuration diagram of a water heater according to a second embodiment of the present invention.

FIG. 5 is a configuration diagram of a conventional balanced water heater.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Water supply pipe 12 Flow switch 13 Water governor 14 Heat exchanger 18 Gas supply pipe 19 Original gas valve 191 Automatic water pressure valve 192 Solenoid valve 20 Burner 23 Switching valve 231 Solenoid valve 232 Automatic water pressure gas valve 28 Branch pipe

Claims (9)

[Claims] 1. A water heater for heating a heat exchanger by a burner, comprising a switching valve for switching a gas supply amount to the burner based on an amount of water supplied to the heat exchanger. . 2. The burner according to claim 1, wherein the burner has a plurality of combustion surfaces, and the switching valve branches from a source gas supply pipe that supplies gas to the burner, and supplies gas to each combustion surface. A water heater characterized in that at least one of a plurality of branch pipes is opened and closed. 3. The water heater according to claim 2, wherein the switching valve is opened when the amount of water supplied to the heat exchanger is equal to or more than a predetermined amount, and closed when the amount of water is smaller than the predetermined amount. 4. The source gas valve according to claim 2, further comprising: a source gas valve for opening and closing the source gas supply pipe; and when a flow rate equal to or more than a first flow rate flows through the heat exchanger, the source gas valve is opened. When the second flow rate larger than the first flow rate flows through the heat exchanger, the switching valve is opened. 5. The water heater according to claim 4, further comprising a diaphragm that moves in accordance with a water pressure of the water flowing into the water heater, and adjusting a water pressure of the water to be sent to the heat exchanger in accordance with the movement of the diaphragm. A water governor is provided, wherein the source gas valve is a hydraulic automatic gas valve that opens and closes the source gas supply pipe in conjunction with movement of the diaphragm when the first flow rate flows through the heat exchanger. Water heater characterized. 6. The flow rate sensor according to claim 4, further comprising a flow rate detecting means for detecting a second flow rate flowing through the heat exchanger, wherein the switching valve detects the second flow rate detected by the flow rate detecting means. A water heater characterized in that it is a solenoid valve that is opened and closed in response. 7. The apparatus according to claim 4, further comprising a flow rate detecting means for detecting a first flow rate flowing through the heat exchanger, wherein the source gas valve is responsive to the first water amount detected by the flow rate detecting means. A water heater characterized in that it is a solenoid valve that can be opened and closed. 8. The water heater according to claim 4, further comprising a diaphragm that moves in accordance with the water pressure of the water flowing into the water heater, and that controls the water pressure of the water that is sent to the heat exchanger in accordance with the movement of the diaphragm. A water governor for adjusting is provided, and the switching valve is a hydraulic automatic gas valve that opens and closes the branch pipe in conjunction with movement of the diaphragm when the second flow rate flows through the heat exchanger. And water heater. 9. A water heater according to claim 6, wherein said flow rate detecting means is a flowing water switch.