JPH0584332B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a hot water mixing hot water supply device that adjusts the mixing ratio of hot water and water to obtain an appropriate temperature.

BACKGROUND ART Conventionally, there has been a hot water mixing water heater of this type as shown in FIG. (For example, Utsukai Showa 59-65315
In FIG. 3, water is supplied to the instantaneous water heater 1 from a water supply pipe 2, and the water is supplied to a heat exchanger 5 via a flow rate detector 3 and an incoming water temperature detector 4, and is heated.
The hot water is supplied from the hot water pipe 6 as hot water. heat exchanger 5
A hot water temperature detector 7 is provided at the outlet of the hot water, and the gas proportional control valve 9 is adjusted so that the hot water temperature reaches a predetermined temperature in the controller 8, thereby controlling the amount of combustion in the burner 10. ing. A mixing valve 11 for adjusting the mixing ratio of hot water and water is provided on the terminal side, and a hot water supply pipe 12 and a water supply pipe 13 from the instantaneous water heater 1 are connected. In operation, when a water stop valve (not shown) at the terminal is opened, water in the hot water supply pipes 12 and 13 starts flowing. The flow rate of water passing through the instantaneous water heater 1 is detected by a flow rate detector 3, and the flow rate of water passing through the instantaneous water heater 1 is detected by a heat exchanger 5.
When the minimum ignition flow rate, which is set to prevent water from boiling inside, reaches a minimum ignition flow rate value, combustion is started according to a command from the controller 8. Based on the signals from the flow rate detector 3, inlet water temperature detector 4, and hot water temperature detector 7, the controller 8 adjusts the opening degree of the gas proportional control valve 9 to adjust the amount of gas burned in the burner 10. There is. The instant water heater 1 is controlled so that hot water is supplied at a predetermined constant temperature. Then, the mixing valve 11 is throttled down, and when the flow rate passing through the instantaneous water heater 1 becomes less than the minimum ignition flow rate, the burner 1
Combustion at 0 stops.

Problems to be Solved by the Invention However, with the above configuration, when the flow rate is throttled by the stop valve or the mixing valve 11, combustion in the instantaneous water heater 1 sometimes stops.

In particular, in the case of an automatic mixing valve that automatically adjusts the mixed water temperature so that the temperature set by the mixing valve 11 is obtained, when the flow rate is throttled down, the flow rate falls below the minimum ignition flow rate of the instantaneous water heater 1, the burner 10 is turned off, and hot water is supplied. As the temperature of the water sent from pipe 12 drops, the mixing valve opens the hot water side.
The flow through the instantaneous water heater 1 increases and again exceeds the minimum ignition flow value, causing the burner 10 to be relit. As a result, when the temperature of the hot water rose, the water side of the mixing valve 11 was opened, the hot water side was throttled, and the burner 10 was extinguished again. For this reason, the burner 10 is repeatedly ignited and extinguished, and the temperature of the mixed hot water supplied from the mixing valve 11 has the problem of cyclical fluctuations.

The present invention solves these conventional problems, and is capable of mixing hot water and hot water with an instantaneous water heater or other hot water heater, which can perform a mixing operation while sustaining the combustion of the hot water supply bar, where combustion is started and stopped depending on the amount of water flowing. The purpose is to provide

Means for Solving the Problems In order to solve the above-mentioned problems, the hot water mixing hot water supply device of the present invention includes a hot water supply bar that starts and stops combustion according to the amount of water flowing, and a hot water supply bar that controls hot water supplied from the hot water supply bar. A mixing valve consisting of a ratio control valve section, a drive section, a temperature detection section, and a temperature setting section that mixes with water to obtain an appropriate temperature; a flow rate sensor that detects the flow rate of the mixed hot water; and a flow rate adjustment valve that adjusts the flow rate of the mixed hot water. This system includes a controller that adjusts a flow rate regulating valve using a signal from a flow rate sensor and prevents hot water from being supplied when the flow rate is below a predetermined flow rate.

Effects According to the present invention, with the above-described configuration, the controller uses the signal from the flow sensor to adjust the flow rate control valve so that the combustion of the hot water supply bar does not stop even if the flow rate control valve throttles the flow rate. Control is performed so that hot water is not supplied below the flow rate value.

Embodiments Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. In FIG. 1, water is supplied to the hot water supply pipe 14 from a water supply pipe 15, and is supplied to a heat exchanger 18 via a flow rate sensor 16 and an incoming water temperature sensor 17 provided inside. Burner 1 in heat exchanger 18
The hot water heated by 9 and raised in temperature is sent to the hot water temperature sensor 2.
0 and is sent to the hot water supply pipe 21. Water temperature sensor 20
The detected hot water temperature signal is sent to the controller 22 and compared with a preset hot water temperature setting value.
Controls the gas proportional control valve 23. A hot water supply pipe 24 and a water supply pipe 25 branched from the hot water supply pipe 21 are connected to a terminal mixing unit 26 having a mixing function and a flow rate adjustment mechanism. This mixing unit 26
Details are shown in Figure 2. Mixing unit 26
The hot water and water introduced into the chamber are led to a mixing valve 28 through a pressure regulator 27 that equalizes the pressure and facilitates control. In the mixing valve 28, a ratio control valve portion consisting of a hot water side valve body, a hot water side valve body 29, and a water side valve body 30 is driven by a drive device 32, which is an external drive unit, via a shaft 31, and controls the mixing ratio of hot water and water. It's being adjusted. The mixed water temperature is detected by a mixed water temperature sensor 33 corresponding to a temperature detection section, and the controller 35 controls the mixing ratio to obtain the mixed water temperature set by the setting device 34. The mixed hot water reaches the flow rate control valve 37 via the flow rate sensor 36. The flow control valve 37 is composed of a control valve body 38 and a drive device 39 for driving the control valve body 38. Finally, the mixed hot water is supplied from the discharge port 40 to the hot water supply target. The controller 35 receives signals from the setting device 34, the mixing water temperature sensor 33, and the flow rate sensor 36, and outputs control outputs to the driving device 32 of the mixing valve 28 and the driving device 39 of the flow rate regulating valve 37.

Effects The present invention has the following effects due to the above configuration.

Hot water switch (not shown) provided in the setting device 34
When turned on, the flow control valve 37 is opened, and the mixing ratio at the mixing valve 28 is adjusted so that the mixed water temperature set by the setting device 34 is obtained.

At this time, a signal from the flow rate sensor 36 is transmitted to the controller 35, and the flow rate regulating valve 37 is opened to an opening degree that allows a flow rate greater than a predetermined flow rate value to be obtained. Further, the control operation of the mixing valve 28 is started when the flow rate is equal to or higher than a predetermined flow rate value. Initially, the temperature inside the hot water supply pipe 24 is also cold, so the mixing valve 28 operates to open the hot water side and throttle the water side. On the other hand, in the water heater 14, when the flow rate control valve 37 is opened, the flow rate sensor 16
detects this, and the burner 19 is ignited when a flow rate greater than a predetermined ignition flow rate is supplied.
At this time, the amount of gas input is determined by calculation from the value of the hot water supply temperature set by the flow rate sensor 16, the incoming water temperature sensor 17, and the controller 22, and the approximate opening degree of the gas proportional control valve 23 is determined. heat exchanger 18
The temperature of the boiling water is detected by a hot water temperature sensor 20, and a gas proportional control valve 23 is finely adjusted via a controller 22. When hot water is supplied, the mixing valve 28 narrows down the hot water side more than before, opens the water side, and adjusts the amounts of hot water and water to a ratio that provides the set mixed hot water temperature. At this time, even if the hot water side is throttled, water heater 1
Care is taken to ensure that the water flow rate does not fall below the minimum ignition flow rate value of No. 4. To explain this point in detail, first, the mixed water temperature is determined by the following formula.

Tm=T _H Q _H +T _W Q _W /Qm...1 Tm: Mixed hot water temperature Qm: 〃 Quantity T _H : Supply water temperature Q _H : 〃 Quantity T _W : Supply water temperature Q _W : 〃 Quantity Therefore, the mixed hot water amount is Qm=T _H Q _H +T _W Q _W /Tm...(2).

Here, Q _W =Qm−Q _H ……(3) Therefore, substituting (3) into (2) to find Qm, Qm=T _H −T _W /Tm−T _W Q _H ……(4 ).

If Q _H = 2/min, T _H = 80℃ T _W = 20℃ Tm = 40℃, then Qm = 8/min.
It becomes min.

That is, this value is the lower limit of the amount of mixed hot water when the minimum ignition flow rate is 2/min, and as long as the predetermined flow rate value exceeds 8/min, combustion in the water heater 14 will not stop.

Thus, in this example, the predetermined flow rate value is
It is determined by the water temperature and hot water temperature supplied to the mixing valve 28, the set temperature of the mixed hot water temperature, and the minimum ignition flow rate value for starting and stopping combustion of the water heater 14.

Returning to the explanation of the operation again, the controller 35 has a flow rate setting section (not shown), and the amount of hot water supplied at a predetermined flow rate or higher is, for example, 10/min 12/min15.
/min can be selected. This selection switch is provided integrally with the setting device 34. When hot water supply becomes unnecessary and the hot water supply switch of the setting device 34 is turned off, the flow control valve 37 is closed and the supply of mixed hot water is stopped. At this time, the driving of the mixing valve 28 is stopped using the signal from the flow rate sensor 36 when the flow rate of the mixed hot water becomes less than a predetermined flow rate value. This is because the mixing valve 28 opens the hot water side and closes the water side as the temperature around the mixed hot water temperature sensor 33 decreases due to natural cooling after the hot water supply is stopped. This prevents hot water from being supplied.

In this embodiment, the predetermined flow rate value is set to the mixing valve 2.
Water temperature and hot water temperature supplied to 8, set temperature of mixed hot water,
Since it is determined based on the flow rate value at the start and stop of combustion in the water heater, it has the effect that the predetermined flow rate value can be set with high accuracy. Further, the controller has a flow rate setting section, and the amount of hot water supplied above a predetermined flow rate value can be selected, which has the effect of increasing convenience. Furthermore, the mixing valve utilizes the signal from the flow rate sensor 36 to
When the flow rate is below a predetermined flow rate, the driving device 32 stops driving the mixing valve 28 and starts driving the mixing valve 28 when the flow rate is above the flow rate, so hot water is not supplied when hot water is re-discharged, which has the effect of preventing danger. There is.

In this embodiment, the mixing valve 28 is of an electrically driven type, but a conventional thermo-type mixing valve may also be used.

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

(1) The flow rate of mixed hot water is determined to ensure that the flow rate of water through the water heater is greater than the flow rate at which the water heater starts and stops combustion, and hot water is not supplied below this predetermined flow rate. This eliminates the need for combustion in the water heater to stop or repeatedly start and stop during the mixing operation, improving usability.

(2) The flow rate value of the flow rate control valve can be set with high precision using the flow rate sensor signal, and it can also be used to control the mixing valve to stop the operation of the mixing valve when the flow rate is below a predetermined value, thereby reducing the danger when re-releasing hot water. prevent, etc.
It is possible to create a device that is effective in terms of accuracy and safety.

(3) Since hot water is not supplied below a predetermined flow rate, both the water heater and the mixing valve do not operate cyclically, and the durability of both can be improved.

[Brief explanation of the drawing]

FIG. 1 is a piping system diagram showing a hot water mixing hot water supply device according to an embodiment of the present invention, FIG. 2 is an enlarged sectional view of the same essential parts, and FIG. 3 is a piping system diagram of a conventional hot water mixing hot water supply device. 14...Water heater, 29...Hot water side valve body (ratio control valve part), 30...Water side valve body (ratio control valve part), 32
... Drive device (drive unit), 33 ... Mixed water temperature sensor (temperature detection section), 35 ... Controller, 36 ... Flow rate sensor, 37 ... Flow rate adjustment valve, 34 ... Setting device (Temperature setting section) ).

Claims (1)

[Scope of Claims] 1. A water heater that starts and stops combustion according to the amount of water flowing, a ratio control valve section, a drive section, and a temperature detection section that mix hot water supplied from the water heater with water to obtain an appropriate temperature. , a mixing valve comprising a temperature setting section, a flow rate sensor for detecting the flow rate of the mixed hot water, a flow rate control valve for adjusting the flow rate of the mixed hot water, and a signal from the flow rate sensor being used to adjust the flow rate control valve to a predetermined value. A hot water mixing hot water supply device consisting of a controller that controls not to supply hot water when the flow rate exceeds the flow rate value. 2. The predetermined flow rate value is determined based on the water temperature and hot water temperature supplied to the mixing valve, the set temperature of the temperature setting section of the mixing valve, and the water flow amount value at the start and stop of combustion. hot water mixing water heater. 3. The hot water mixing hot water supply device according to claim 1, wherein the controller has a flow rate setting section, and the amount of hot water supplied above a predetermined flow rate value can be selected. 4. The mixing valve utilizes the signal from the flow rate sensor to stop the operation of the drive unit when the flow rate is below a predetermined flow value, and to operate the drive unit when the flow rate is above a predetermined flow value.
The hot water mixing hot water supply device described in Section 1.