JPH0459539B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a water heater equipped with a hot water ratio control valve that can supply hot water at any temperature level.

BACKGROUND ART Conventionally, there has been a water heater of this type as shown in FIG. In other words, in Fig. 3, the valve stem 1
is adapted to move forward and backward by driving a servo motor 1'. Reference numeral 2 denotes a double-sided valve on the hot water side for adjusting the amount of high-temperature hot water. Reference numeral 4 denotes a single-sided valve on the water side for adjusting the amount of cold water, and a spring 5 is interposed between it and the double-sided valve 2 on the hot water side, so that it is movable only in the direction of the double-sided valve 2 on the hot water side with respect to the valve shaft 1. . Further, 6 is one hot water side sheet formed at the outlet of the hot water supply path 8 in the hot water side valve chamber 7, and 9
is the other hot water side sheet formed in the hot water side valve chamber 7 opposite to the hot water side sheet 6, and the hot water side sheet 9 is disposed between the hot water side valve chamber 7 and a mixing chamber 11 to be described later. There is. The hot water side double-sided valve 2 is installed between these two hot water side seats 6, 9, and the hot water side double-sided valve 2 is connected to the two hot water side seats 6, 9 by moving the valve shaft 1 back and forth.
9, the contact and separation relationships are inverse to each other, and the respective opening degrees are adjusted. 10 is a water side sheet formed at the outlet of the water supply channel 12 in the mixing chamber 11 which also serves as a water side valve chamber;
In this case, the water side single-sided valve 4 is moved closer and closer to and away from the valve shaft 1 by moving the valve shaft 1 back and forth to change and adjust its opening degree. Note that water whose pressure has been reduced by a pressure reducing valve 13 is heated by a heat exchanger 14 of a water heater and then supplied to the hot water supply path 8. In other words, the water whose pressure has been reduced by the pressure reducing valve 13 is
The water is divided into the water supply channel 12 side and the water heater heat exchanger 14 side, the flow rate ratio is adjusted by the double-sided valve 2 on the hot water side and the single-sided valve 4 on the water side, and the hot water and water are mixed in the mixing chamber 11.
Hot water is supplied from the mixed hot water outlet path 15 to the hot water supply target.

Problems to be Solved by the Invention Since the conventional water heater is configured as described above, when the hot water supply is stopped, the hot water stored in the heat exchanger 14 is transferred to the hot water supply path 8 and the mixing chamber 11. , as the water supply channel 12 etc. are cooled,
Due to natural circulation, the temperature gradually decreases.

At the initial stage of cooling, the temperature inside the hot water supply channel 8 and the water supply channel 12 is not much different from the temperature during hot water supply use, but at the stage when the temperature inside the water supply channel 12 gradually rises due to natural circulation. When hot water is resupplied, a temperature higher than the set temperature is temporarily supplied, which is dangerous.

Furthermore, when hot water supply is resumed after a long period of time has passed and hot water supply channel 8 and water supply channel 12 have sufficiently cooled down due to natural heat radiation, water supply channel 12 is closed until hot water supply channel 8 is fully opened. Because it takes time to
It took a while to get the temperature right. In addition, if a certain amount of time has elapsed and the temperature of the supplied hot water changes temporarily during refilling, but it is predicted that the temperature will return to a constant level relatively soon, applying the control will instead cause the mixture to change. It was predicted that there would be cases where it would be better to stop the control for a certain period of time because the water temperature would fluctuate.

The present invention solves the above-mentioned conventional problems, and aims to provide a water heater that can quickly supply mixed hot water at a temperature close to a set temperature at all times.

Means for Solving the Problems In order to achieve the above object, the water heater of the present invention includes a hot water supply path and a ratio control valve that adjusts the ratio of hot water passing through the water supply path, and a temperature sensor that detects the temperature of the mixed water. , a temperature setting device that sets the mixed water temperature, a hot water supply detector that detects the presence or absence of hot water supply, and a ratio control valve is controlled by the signals from the temperature detector and temperature setting device, and the hot water supply detector detects the start of hot water supply. and a controller that adjusts how the ratio control valve enters the ratio control operation from the hot water side opening operation in accordance with the temperature of the temperature detector at the time when the ratio control valve is opened.

Effect With the above-described configuration, the water heater of the present invention detects the start of hot water supply with the hot water supply detector when restarting hot water supply, and checks the signal of the temperature detector to determine whether the temperature has fallen sufficiently below the set temperature. In this case, the hot water side is kept open temporarily, and after the cold water in the hot water supply path is discharged, normal ratio control operation is started to quickly obtain mixed hot water at a temperature close to the set temperature. .

Embodiment Next, an embodiment of the present invention will be described with reference to FIGS. 1 and 2.

FIG. 1 shows an example in which the present invention is applied to an electric water heater that uses late-night electricity.

Reference numeral 16 denotes a hot water supply heat source device, an electric water heater that uses late-night electricity, and is composed of a heater 17 and a hot water storage tank 18.

The electric water heater 16 is connected to water supply routes 19 and 19', a mixed hot water route 20, and a hot water supply route 20', and a bypass route 21 branches from the water supply route 19 and joins the mixed hot water route 20. Water supply route 19
A ratio control valve 22 for adjusting the flow rate ratio of hot water and water is provided at a branch point of the bypass path 21. A pressure reducing check valve 23 reduces the water pressure and prevents hot water from flowing back into the water supply path in the event of a water outage or the like. After the bypass path 21 of the mixed hot water path 20 joins, a flow rate switch 24 which is a hot water supply detector that detects the presence or absence of hot water supply and a temperature detector 25 that detects the temperature of the mixed water after the hot water and water are mixed are provided. It is being There is a faucet 2 at the terminal of the mixed hot water route 20.
6, 27 are connected, and near the faucets 26, 27 there are temperature setting devices 28, 29 for setting the hot water temperature.
is installed. The temperature setters 28 and 29 have a priority and subordinate relationship, and when used simultaneously, hot water is supplied according to the temperature setting of the priority side.
Signals from the temperature setters 28 and 29, the temperature detector 25 and the flow rate switch 24 are sent to the control device 30,
Control device 30 controls ratio control valve 22 based on these signals.

The ratio control valve 22 is constructed as shown in FIG. Water entering from the water supply route 19 is branched inside the valve frame 31 into a water supply route 19' side leading to the electric water heater 16 and a bypass route 21 side. Inside the valve frame body 31, a hot water side valve body 32 and a water side valve body 33 are provided on a shaft 34, and are biased in the direction of spreading by a spring 35 to a regulated predetermined interval. The hot water side valve body 32 and the water side valve body 33 are connected to the shaft 34
is driven left and right in the figure by the drive unit 36, thereby changing the ratio of hot water to water. The drive section 36 includes a motor 37, a gearbox 38 which is a speed reduction mechanism, and a threaded section 39 which converts rotational motion into linear motion. Moreover, 40 is a micro switch, which stops the driving of the hot water side valve body 33 and the water side valve body 34 after the closing point, and plays the role of preventing overshooting.

Next, the operation of this embodiment will be explained.

When the faucet 26 or 27 is open and hot water is being supplied, the flow rate switch 24 is activated;
The ratio control valve 22 controls the ratio of the amount of water supplied to the electric water heater 16 and the amount of water passing through the bypass path 21 so that the water temperature reaches the temperature set by the temperature setting device 28 or 29.

Specifically, the motor 37 is driven to a position where there is no temperature deviation between the set temperature of the temperature setter 28 or 29 and the temperature detected by the temperature detector 25, and the mixing ratio of hot water and water is adjusted. When all faucets are closed and hot water supply is stopped, the flow rate switch 24 detects the stoppage of hot water supply and holds the ratio control valve 22 at the hot water supply stop position for a predetermined period of time. If hot water is to be re-supplied within a short period of time after the hot-water supply is stopped, the control device 30 determines that the temperature detected by the temperature detector 25 is not significantly different from the set temperature, and immediately controls the mixing ratio. to go into. Next, after a predetermined period of time has elapsed after the hot water supply is stopped, the ratio control valve 22 is driven to disconnect the bypass path 21 from the electric water heater 16. That is, the ratio control valve 22 shown in FIG. 2 is driven leftward in the figure, and the water side valve body 33 is brought into contact with the valve seat and closed. Bypass path 21 and electric water heater 16 are connected to hot water pipe 20
', the bypass path 21, the ratio control valve 22, the water supply pipe 19', and the electric water heater 16 form a loop, but by closing the ratio control valve 22, communication between them is cut off. Therefore, it is possible to prevent heat radiation from the hot water in the hot water storage tank 18 due to natural heat radiation that occurs through the loop when hot water is not being supplied.
Further, even if the temperature in the bypass path 21 rises due to natural circulation, the temperature of the mixed hot water will not overshoot when hot water is re-supplied. When resupplying hot water after stopping hot water supply for a long time, when the faucet 26 or 27 is opened, the hot water in the electric water heater 16 flows and cools because the bypass side 21 is closed when the hot water supply is stopped in this embodiment. The hot water supply route 20, which had been
Speed up the supply of hot water to the faucet. The start of hot water supply is also detected by the flow rate switch 24, but after the start of hot water supply, the flow of hot water to the mixed hot water path 20 is continued for a predetermined time depending on the temperature of the temperature detector 25, or until a predetermined temperature is obtained. Hot water from the electric water heater 16 is supplied, and then ratio control is applied to bring the original mixed water temperature to the set value. As described above, this embodiment reduces heat radiation loss when hot water is not used, and
This speeds up the rise in temperature of hot water when it is reused. Even if the water heater is an instantaneous type, you can check the temperature on the temperature sensor when restarting hot water supply, keep the hot water side open for a while, and switch to normal ratio control operation when the temperature rises. You can quickly reach the right temperature.

The ratio control valve 22 can be driven in the direction of closing the hot water side or the water side after a predetermined period of time has passed after the hot water supply is stopped, and the path may be slightly opened instead of being completely closed. In this case, for example, in the winter, the bypass pipe 2
1 can be prevented from being cooled and frozen by raising the temperature to an appropriate level without causing an overshoot when hot water is reheated. Furthermore, if the temperature of the hot water being supplied is predicted to rise rapidly, waiting without fully opening the hot water side allows the next ratio control operation to be started quickly while suppressing overshoot. In these cases as well, the manner in which the ratio control operation is entered can be changed depending on the signal from the temperature sensor.

In this embodiment, the flow rate switch 24 is used as the hot water supply detector, but the hot water supply detector can also be a switch that turns on and off in conjunction with faucet operation, or a valve switch that opens and closes in conjunction with switch operation. There are methods that use signals and methods that detect the internal pressure of the hot water supply route. Furthermore, although the ratio control valve 22 is provided at the branching point of the water supply path 19 and the bypass path 21 in this embodiment, it may be provided at the confluence of the hot water supply path 20' and the bypass path 21.

Effects of the Invention As described above, the water heater of the present invention includes a hot water supply path and a ratio control valve that adjusts the ratio of hot water supplied through the water supply path, a temperature sensor that detects the temperature of mixed hot water, and a temperature sensor that detects the temperature of mixed hot water. a temperature setting device to set the water supply, a hot water supply detector to detect the presence or absence of hot water supply, a ratio control valve is controlled by the signals from the temperature detector and the temperature setting device, and the temperature at the time when the hot water supply detector detects that the hot water supply has stopped. Since it is equipped with a controller that adjusts the way the ratio control valve enters the ratio control operation from the hot water side opening operation according to the temperature of the temperature detector, it has the following effects (1) Hot water supply continues for a long time. If the ratio control valve is restarted after the hot water side is not opened, the ratio control valve is held in a state where the hot water side is opened more than the water side, and the ratio control valve starts normal ratio control operation after a predetermined time or a predetermined temperature. Stagnant water can be discharged quickly and the set temperature can be reached quickly.

(2) Since the entry into normal ratio control operation is determined based on the temperature detected by the temperature sensor, for example, after the hot water supply detector detects the start of hot water supply, the ratio control operation is continued for a predetermined period of time. Control can be performed more safely and reliably than with methods that do not perform

[Brief explanation of drawings]

Figure 1 is a configuration diagram of a hot water supply system using a water heater according to an embodiment of the present invention, Figure 2 is a sectional view of a ratio control valve used in the same equipment, and Figure 3 is a sectional view of a conventional water heater. It is. 16...Electric water heater (hot water heat source machine), 19,1
9'...Water supply route, 20...Mixed hot water route, 20'
... Hot water supply path, 21 ... Bypass path (water supply path), 22 ... Ratio control valve, 24 ... Flow rate switch (hot water supply detector), 25 ... Temperature detector, 28,
29... Temperature setting device, 30... Control device (controller).

Claims (1)

[Claims] 1. A hot water supply route connected to a hot water supply heat source device, a water supply route, a mixed hot water route where the hot water supply route and the water supply route are merged, and a ratio that controls the ratio of hot water passing through the hot water supply route to water passing through the water supply route. a control valve, a temperature detector that detects the mixed water temperature after hot water and water are combined and mixed, a temperature setting device that sets the mixed water temperature, a hot water supply detector that detects the presence or absence of hot water supply, and the temperature detection device. The ratio control valve is controlled by a signal from a temperature setting device and a temperature setting device, and according to the temperature of the temperature detector at the time when the hot water supply detector detects the start of hot water supply,
and a controller that adjusts how the ratio control valve enters the ratio control operation from the hot water side opening operation.