JPH0579885B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a circulating hot water supply device that circulates hot water to realize instantaneous hot water supply and adjusts the desired hot water temperature to supply hot water.

Conventional Structure and Problems There has been a conventional circulating hot water supply device of this type as shown in FIG.

In FIG. 1, 1 is a cistern for water supply, and water is supplied to the hot water supply heat source device 2 via a water supply pipe 3. Hot water produced by the hot water supply heat source device 2 is circulated from the hot water supply pipe 4 to the hot water supply return pipe 5 by a circulation pump 6, and returns to the hot water supply heat source device 2 again via the water supply pipe 7 and the water supply pipe 3. The hot water supply pipe 4 has a hot water mixing valve 8
is connected, and a water supply pipe 7 that is supplied from the cistern 1 is also connected, and the hot water from the hot water supply heat source device 2 and the water that has passed through the water supply pipe 7 are mixed. Mixed hot water is supplied from hot water taps 9 and 10 through a hot water supply pipe 4. Reference numeral 11 denotes a flow switch, which determines whether the hot water taps 9 and 10 are open or not as a flow rate value.

In operation, when the hot water taps 9 and 10 are open, the flow switch 11 detects that the flow rate is low, reduces the capacity of the circulation pump 6, and circulates at a low pressure. When the hot water taps 9 and 10 are opened, the flow switch 11 detects that the flow is large and causes the circulation pump 6 to perform pressurized circulation. The remaining hot water supplied by the hot water taps 9 and 10 returns to the hot water heat source device 2 via the hot water return pipe 5. The hot water mixing valve 8 mixes and supplies hot water from the hot water supply heat source device 2, circulating hot water from the hot water supply return pipe 5, and water from the water supply pipe 7.

Since the conventional circulating hot water supply device was configured as described above, it had the following problems.

(1) During hot water supply, the hot water mixing valve 8 mixes hot water from the hot water heat source device 2 with hot water, which is a mixture of water from the water supply pipe 7 and circulating hot water from the hot water supply return pipe 5, so that the hot water temperature The hot water temperature level could only be set within the hot water temperature range, and the hot water temperature was limited.

(2) If there is an increase or decrease in the number of hot water taps used during hot water supply, the amount of circulating hot water from the hot water supply return pipe 5 will fluctuate, and the mixing ratio with water from the water supply pipe 7 will change.
The hot water temperature fluctuated.

(3) Even during hot water supply, the circulation of hot water continues through the hot water supply return pipe 5, which increases heat radiation loss and goes against energy conservation.

Purpose of the Invention The present invention solves these conventional problems, and provides a circulating hot water supply device that expands the usable hot water temperature level by stopping the circulation during hot water supply, and reduces heat radiation loss. The purpose is to

Structure of the Invention In order to achieve this object, the present invention provides a hot water supply heat source device, a circulation circuit consisting of a hot water supply pipe and a hot water supply return pipe connected to the hot water supply heat source device, a hot water tap provided in this circulation circuit, and a circulation circuit. The pump, the water supply pipe that supplies water to the hot water heat source machine, the water supply bypass pipe that bypasses the hot water heat source machine and connects to the hot water supply pipe, the primary water supply pipe, the water supply pipe, the water supply bypass pipe, and the hot water return pipe are connected to supply hot water. A hot water mixing valve that can be fully closed at least on the water supply pipe side to control the mixing ratio of hot water supplied from the heat source equipment and water supplied from the water supply bypass pipe, a temperature sensor that detects the mixed water temperature, and a temperature sensor that sets the mixed water temperature. a control valve provided on the hot water supply return pipe; a hot water supply detection means for detecting whether or not hot water is being supplied; A circulating hot water supply device includes a controller that closes the hot water supply return pipe using the control valve when hot water supply is detected by the hot water supply detection means, and hot water from the water heater is circulated through the circulation circuit by the circulation pump to start hot water supply. When the hot water tap is opened and hot water is being supplied, the control valve closes the hot water return pipe based on the signal from the hot water detection means to stop the circulation and reduce the heat radiation loss on the hot water return pipe side. In addition, by closing the control valve, we prevent hot water from the hot water supply return pipe from mixing with the water supply pipe, and by closing the water supply pipe leading to the hot water heat source equipment using the hot water mixing valve, we can supply only water. This expands the usable temperature range of mixed hot water whose temperature is controlled by the hot water mixing valve.

DESCRIPTION OF EMBODIMENTS Next, regarding embodiments of the present invention, FIGS.
This will be explained using figures.

In FIG. 2, 12 is a hot water supply heat source machine, and a hot water supply pipe 13 and a hot water supply return pipe 14 are connected to this hot water supply machine 12 to form a circulation circuit. The hot water return pipe 14 is provided with a circulation pump 15, and the hot water return pipe 14 includes a water supply pipe 16' that supplies water to the hot water heat source device 12 and a water supply pipe 16 that is a primary water supply pipe.
The hot water mixing valve 17 is connected to the hot water mixing valve 17. A water supply bypass pipe 18 that is connected to the hot water supply pipe 13 branches off from the hot water mixing valve 17 . A temperature detector 19 is provided downstream from the junction of the hot water supply pipe 13 and the water supply bypass pipe 18 to detect the temperature of the mixed hot water. Reference numerals 20 and 21 are both flow rate sensors, which constitute hot water supply detection means for determining whether or not hot water is being supplied.
3 and the amount of hot water flowing through the hot water supply return pipe 14 is measured. Temperature setters 24 and 25 are provided near the hot water taps 22 and 23 provided in the circulation circuit composed of the hot water supply pipe 13 and the hot water supply return pipe 14, and the temperature setters 24 and 25 and the temperature detector The signal is sent to the control circuit 26 to control the hot water mixing valve 17.

Here, the hot water mixing valve 17 is constructed as shown in FIG. Motor 27 and gearbox 28
A drive section 29 is configured, and rotation of the drive section 29 is transmitted to a valve section 31 via a shaft 30. Valve part 31
has four connection ports 32, 33, 34, and 35, and a cylindrical stopper 38 with an opening 37 is provided in the valve frame 36, and the mixing ratio of hot water and water can be changed by rotation. or control the opening and closing of the connection port. As for the connection ports, the connection port 32 is connected to the hot water supply return pipe 14, the connection port 33 is connected to the water supply pipe 16, the connection port 34 is connected to the water supply bypass pipe 18, and the connection port 35 is connected to the water supply pipe 16'.

Further, the hot water mixing valve 17 is designed to completely close the water supply pipe 16' leading to the hot water heat source device 12, so that only water can be supplied.

Next, the operation will be explained.

When the hot water supply tap 22 or 23 is opened and hot water is being supplied, the hot water mixing valve 17 is turned on and off in the range from a to d in FIG. 4 so that the temperature is set by the temperature setting device 24 or 25. The mixing ratio of water is adjusted. For example, a is a mode in which hot water is supplied at the maximum temperature, c is a mode at a medium temperature, and d is a mode in which hot water is supplied at a water temperature level. This mixed water temperature is adjusted by the control circuit 26.
The signal from the temperature setter 24 and the signal from the temperature detector 19 are compared, and this is done by adjusting the motor 27 and changing the mixing ratio so as to eliminate the deviation.

In modes a to d for supplying hot water, the connection port 32 connected to the hot water supply return pipe 14 is closed by a cylindrical stopper 38. Therefore, circulating hot water from the hot water supply return pipe 14 does not mix with water during hot water supply. In addition, as shown in d, the communication to the water heater side is cut off to prevent hot water from mixing and increasing the supply temperature when hot water is supplied at the water temperature level. When hot water is being supplied, there is a difference in flow rate values between the flow rate sensors 20 and 21, and the hot water mixing valve 17 maintains the hot water supply mode and disconnects from the hot water supply return pipe 14.

When the hot water tap 22 or 23 that was being used is closed, the flow rates of the flow rate sensors 20 and 21 to stop the flow both become zero, and since there is no difference in flow rate, this is detected and the hot water mixing valve 17 is turned on. Figure 4 e
Or switch like f. By this switching, the bypass water supply pipe 18 is closed, and hot water from the hot water supply heat source device 12 is circulated from the hot water supply pipe 13 through the hot water return pipe 14 by the circulation pump 15 started at the same time. When hot water supply is restarted, the flow rate detected by the flow rate sensor 20 becomes larger than the flow rate detected by the flow rate sensor 21, and the difference is caught and the hot water mixing valve 17 is returned to the state described above.

If you do not use hot water at all and do not need circulation, turn off the main switch (not shown).
The hot water mixing valve is switched as shown in g in FIG. 4, and the circulation pump 15 is also stopped.

The effects of this embodiment include the hot water mixing valve 1
7 also plays the role of a control valve that controls opening and closing of the hot water supply return pipe 14 during hot water supply, so only one valve/actuator is required, which can be advantageous in terms of configuration and cost. In addition, since the hot water mixing valve 17 is installed in the water supply pipe 16, no heat is applied to the hot water mixing valve 17 during hot water supply, so there is less steel deposited from the hot water, and the durability of the valve 17 is also reduced in terms of materials. It has the effect of stretching etc.

In this embodiment, the control valve is provided integrally with the hot water mixing valve, but it may be provided separately. In this case the control valve is connected directly to the hot water return pipe.

Effects of the Invention The present invention provides a circulating hot water supply device having a hot water mixing valve, in which the circulating circuit is closed by a control valve during hot water supply;
Since the structure is designed to prevent circulating hot water from returning, it has the following effects.

(1) Since the hot water supply return pipe is closed by the control valve during hot water supply, low-temperature circulating hot water does not mix with the hot water mixing valve section, and the hot water mixing valve is equipped with a hot water mixing valve that can be closed on the hot water side. The temperature range of the mixed hot water is not narrowed, and hot water can be supplied at any stable temperature from the boiling water level to the cold water level.

(2) Since the hot water supply detection means detects the start of hot water supply when the hot water tap is opened and switches the mode, hot water supply can begin immediately when the hot water tap is opened, even if the inside of the piping has not yet reached the operating temperature. However, this unnecessary hot water can be quickly discharged, and it takes less time to reach the appropriate temperature. Furthermore, it is possible to prevent the inconvenience that hot water does not come out even when the hot water tap is opened, resulting in a false recognition that the hot water supply valve is malfunctioning, or that hot water supply starts while the user is away from the hot water tap.

(3) When hot water is being supplied from the hot water tap, the control valve installed in the hot water return pipe is closed, stopping the circulation of hot water and preventing heat radiation from the hot water return pipe.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a hot water supply system showing a conventional circulating hot water supply device, Fig. 2 is a block diagram of a hot water supply system showing an embodiment of the circulating hot water supply device of the present invention, and Fig. 3 is a hot water mixing system used in the same device. A sectional view of the valve and FIG. 4 are explanatory views of the operation of the hot water mixing valve. 12...Hot water heat source machine, 13...Hot water supply pipe, 1
4...Hot water return pipe, 15...Circulation pump, 16...
...Water supply primary pipe, 16'...Water supply pipe, 17...Hot water mixing valve (control valve), 18...Water supply bypass pipe, 1
9... Temperature detector, 24, 25... Temperature setting device,
26...Control circuit.

Claims (1)

[Scope of Claims] 1. A circulating circuit consisting of a hot water supply heat source machine, a hot water supply pipe and a hot water return pipe connected to the hot water supply heat source machine,
A hot water tap and a circulation pump installed in this circulation circuit,
A water supply pipe that supplies water to the hot water supply heat source machine, a water supply bypass pipe that bypasses the hot water supply heat source machine and connects to the hot water supply pipe, a primary water supply pipe, the water supply pipe, the water supply bypass pipe, and a hot water supply return pipe are connected. a hot water mixing valve that can be fully closed at least on the water supply pipe side for controlling the mixing ratio of hot water supplied from the hot water supply heat source device and water supplied from the water supply bypass pipe; a temperature sensor that detects the temperature of the mixed water; a temperature setting device for setting the temperature of hot water; a control valve provided on the hot water supply return pipe; a hot water supply detection means for detecting whether hot water is being supplied; and a hot water mixing valve based on signals from the temperature setting device and the temperature detector. and a controller for controlling the hot water supply return pipe with the control valve when hot water supply is detected by the hot water supply detection means. 2. The circulating hot water supply device according to claim 1, wherein a control valve is integrated into the hot water mixing valve.