JPS6237050Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Field of Application) The present invention relates to a hot water supply unit that can be used in a stop-start hot water supply system to prevent a drop in the temperature of hot water in each hot water supply pipe.

(Prior art) Domestic hot water heaters are generally of a first stop type and have a hot water storage system that replenishes water in proportion to hot water consumption, and there is no problem when using it frequently. If you open the hot water faucet when you need hot water after not using it for a long time, there is an inconvenience that lukewarm water will come out for a while because the water temperature in the hot water supply pipe has dropped.

Especially at night in winter, the temperature of the hot water in the hot water storage tank is high, but the hot water taps and piping inside the hot water unit are cooled by the atmosphere, and in extreme cases can drop to freezing temperatures, which can lead to damage to the piping and faucets. It was hot too.

Therefore, in order to prevent the temperature of hot water at hand from dropping and to prevent damage caused by freezing, for example,
An improved device has been provided as shown in Japanese Patent No. 56-30782.

The main parts of this water heater are shown in Figs. 3 and 4, but the water pressure is higher than the secondary side water pressure of the hot water storage tank 37.
The feature is that a hot water discharge valve (see Fig. 4) with an operating pressure set lower than the set pressure of the safety valve 40 to prevent overpressure is used for the hot water tap 36, and a heater is installed in the hot water storage tank 37. (not shown) The expansion of the water that occurs when the water is heated passes through the hot water supply pipe 38,
Since water is drained from the hot water tap 36 through the universal faucet 47 from the hot water discharge valve 48, it is said that freezing of the hot water pipe 38 can be prevented and hot water can be supplied without interruption during use.

In addition, in Figures 3 and 4, 31 is a water pipe, 32
is a pressure reducing valve, 33 is a water supply pipe, 34 is a branch pipe, 35
is the water heater, 41 is the water supply knob, 42 is the water supply port, 4
3 and 46 are water stop pieces, 44 is a hot water supply knob, 45 is a hot water supply opening, 49 is a spring, 50 is a packing,
51, 52 are seat valve seats, 53 is a pressure adjustment screw, 54
indicate drainage channels.

(Problem to be solved by the invention) However, the above-mentioned hot water supply device achieves its intended purpose when hot water is used under normal conditions. After this temperature is reached, if hot water is not supplied for a long time, such as when it is not in use late at night in winter, the hot water storage tank 37 generally has very good heat retention and the temperature decreases slowly, so reheating operation is not required. On the other hand, this is rarely done, but since the hot water tap 36 is easily affected by the atmospheric temperature and easily drops to freezing temperature in a short period of time, freezing occurs without hot water being sent to the hot water tap 36. Furthermore, even if the water does not freeze, if you try to use hot water after a long interruption, lukewarm water will initially come out, and it is difficult to say that such a device can fully achieve the purpose in any case. Protection in case the piping inside the hot water supply unit freezes when the hot water tap 36 side is installed indoors and there is no risk of freezing, and the hot water supply unit equipped with the hot water storage tank 37 is affected by outside air. remains unfulfilled, and there are still problems to be solved.

The present invention was devised to deal with this situation and eliminate the defects of conventional devices. An important objective of the present invention is not only that it is possible to supply hot water, but also that it is possible to prevent freezing accidents around each pipe.

(Means for Solving the Problems) However, as is clear from the drawings showing the embodiments, the present invention includes a hot water storage tank 2 and a hot water tap 8.
In a hot water unit in which a hot water supply pipe 3 is connected to the hot water storage tank 2 to connect a hot water supply pipe 7 to which the hot water pipes 7a, 8b, and 8c are connected, a pump 9 is interposed in the hot water pipe 3, and a pump 9 is connected to the water supply pipe 3. On the other hand, a bypass pipe 18 is provided which branches from the water supply pipe 3 on the downstream side and is connected to the hot water storage tank 2, and a first capillary tube 15 and a second capillary tube 16 are interposed in series in the bypass pipe 18, and
The connection pipe 26 for connecting the hot water return pipe 10 connected to the most downstream part A of the hot water supply pipe 7 is connected to the first
A solenoid valve 17 is interposed in the bypass pipe 18 which branches from the bypass pipe 18 between the thin tube 15 and the second thin tube 16, and between the branch point of the connecting pipe 26 and the hot water storage tank 2, and further prevents freezing. The present invention is characterized in that a control circuit is provided for operating the pump 9 and opening the electromagnetic valve 17 in response to commands from the freeze detection means 22.

(Function) The present invention provides a bypass pipe 18 having a second thin pipe 16 for the series pipe line of the hot water supply pipe 7 and the hot water return pipe 10.
are connected in series, so the hot water taps 8a to 8c
When there is a risk of freezing on the side, the throttling resistance of the second capillary tube 16 allows the minimum amount of hot water necessary to prevent freezing to be circulated throughout the piping system, while the hot water supply piping 7 side is exposed to outside air. Under conditions of use where there is no extreme influence and there is no risk of freezing,
The hot water return pipe 10 may be omitted; in this case, the first
Since the thin tubes 15 are provided, a small amount of hot water is circulated through all the piping within the hot water supply unit 1, so that freezing of the piping on the hot water supply unit 1 side is prevented.

Moreover, since the amount of hot water bypassed by the first thin tube 15 and the second thin tube 16 can be set to the minimum necessary amount, a sufficient amount of hot water on the hot water supply pipe 7 side during normal operation can be ensured.

(Example) Hereinafter, an example of the present invention will be described in detail based on the accompanying drawings.

FIG. 1 shows a water heater according to an embodiment of the present invention, which shows a lower water supply using an open hot water storage tank 2;
The hot water supply unit 1 is of a top pumping type and is equipped with an antifreeze device.

The hot water supply unit 1 includes a hot water storage tank 2 surrounded by a heat insulating material, and the hot water storage tank 2 has a built-in heater 6 and a water pipe provided with a water supply valve 5 and a metered water supply mechanism 24 such as a ball tap. 4 is connected to the hot water storage tank 2, and a conduit 25 is provided upright in the hot water storage tank 2 for guiding the water discharged from the metered water supply mechanism 24 to the upper part of the tank 2 to the bottom of the tank.

The hot water storage tank 2 in the hot water supply unit 1 includes:
A pipe connection port is opened in the side wall at a position slightly below a predetermined liquid level, and a hot water supply pipe 3 is connected to this pipe connection port.

The hot water pipe 3 has a pipe joint 27 at its end for connecting the hot water supply pipe 7, and a pump 9, a check valve 10, an accumulator 12 with a pressure switch 14, and a flow switch 13 are installed in the middle of the pipe. are arranged in series.

Furthermore, the hot water pipe 3 is branched from a point near the pipe joint 27 on the downstream side of the pump 9 to extend a bypass pipe 18, and the end of the bypass pipe 18 is connected to a suitable point in the hot water storage tank 2, for example. It is connected to the bottom, and a circulation path is formed by the hot water storage tank 2, the hot water supply pipe 3, and the bypass pipe 18.

A first capillary tube 15 and a second capillary tube 16 having throttling resistance are interposed in series in the bypass tube 18, and a bypass tube 18 between the two capillary tubes 15 and 16 is disposed in series.
A connecting pipe 26 is provided branching off from the pipe and having a pipe joint 28 at its tip.

Additionally, this bypass pipe 18 includes a connecting pipe 26.
A solenoid valve 17 is interposed at an appropriate location between the branch point of the hot water storage tank 2 and the hot water storage tank 2, for example, at a location closer to the hot water storage tank 2 than the second thin tube 16.

For the hot water supply unit 1 having the above structure,
The pipe joint 27 is extended to the point of demand,
and connects the hot water supply pipe 7 in which the hot water supply taps 8a, 8b, and 8c are branched and connected, and furthermore, connects the most downstream part A to which the hot water supply tap 8a furthest in the hot water supply pipe 7 is connected, and the pipe joint 28. In between, a hot water return pipe 10 is connected as necessary.

In addition, in FIG. 1, 19 indicates a drain pipe provided with a drain valve 29 in the middle.

The circuit that controls the operation of the hot water supply unit is shown in FIG. 2, which detects the heater 6, the motor _9M for the pump 9, the solenoid _17S of the solenoid valve 17, the timer 20, and the hot water temperature in the hot water storage tank 2. The elements include a hot water temperature thermometer 21, a flow switch 13, a pressure switch 14, an outside air thermometer 22 and a switch 23 that detect outside air temperature as a freezing detection means, and a heater 6 and a hot water temperature thermometer 21 that opens when the temperature is high.
A circuit in series with the output contact of switch 23
Outside air thermostat 22 connected in parallel and opened at high temperature
A circuit in series between the output contact of the solenoid _17S and the driving part 20b of the timer 20, a circuit in series with the output contact 20a of the time-limited operation and time-limited return type of the timer 20, and a circuit in series with the output contact 20a of the timer 20. The output contact of the pressure switch 14 which closes when the pressure switch 14 is closed, the other output contact 20a of the timer 20 connected in parallel with the flow switch 13, and a circuit connected in series with the motor _9M coil.

The timer 20 is an on-delay repeat timer that is activated by energizing the drive unit, and when the total time measured after starting the drive reaches the set time, both output contacts 20a are closed and the closed state is reached. After being connected for a set period of time, it automatically resets and starts measuring again.

On the other hand, the switch 23 functions as a changeover switch for switching automatic operation using the outside air thermostat 22 to forced operation.

To briefly explain the operation of the water heater having the above configuration, the heater 6 is automatically turned on and off by the output contact of the hot water temperature thermometer 21, so that the water temperature in the hot water storage tank 2 is maintained at the set temperature. On the other hand, when any of the hot water supply faucets 8a to 8c is opened and the pressure in the hot water supply pipe 7 decreases, the pressure switch 14 is closed and the motor _9M of the pump 9 is driven to start hot water supply, and at the same time the flow switch 13 is is closed and operates to maintain the drive of motor _9M .

On the other hand, water is automatically supplied into the hot water storage tank 2 according to the amount of hot water used.

By the way, when the outside temperature drops significantly, such as at night during winter, the output contact of the outside air thermostat 22 closes, so the timer 20 is activated to close the output contact 20a for several minutes every few hours as described above. As a result,
The pump 9 is energized only during these few minutes.

As the pump 9 is energized, the hot water accumulated in the hot water supply pipe 7 is returned to the hot water storage tank 2 from the end part A via the hot water return pipe 10, and at the same time, the hot water is returned to the hot water storage tank 2.
Since the hot water in the hot water supply pipe 7 is supplied to the hot water supply pipe 7 in an amount limited by the resistance of the second thin tube 16, the hot water in the hot water supply pipe 7 becomes equal temperature with the hot water in the hot water storage tank 2, and the hot water in the hot water supply tap 8a - 8c are also heated indirectly, and as a result, freezing accidents at the hot water taps 8a to 8c are prevented, and even if the hot water tap is opened after a long period of non-use, hot water at a high temperature is supplied from the beginning. can be supplied.

Needless to say, at the same time as the hot water is being fed to the hot water supply pipe 7 described above, a small amount of high temperature hot water also flows into the first capillary tube 15.

Regarding the operation of the pump 9, in addition to time control using a timer, the temperature of hot water at a point in the hot water supply piping 7 where the temperature decreases fastest, such as the bypass pipe 18 or the most downstream part A in the piping inside the hot water supply unit 1, is detected. The pump 9 is equipped with a thermostat to
A control mode in which the timer 20 is driven is also possible, and the time may be adjusted by shortening the repetition period of the timer 20 in accordance with a decrease in outside temperature.

In addition, since the pump 9 has a large capacity to ensure the amount of hot water to be delivered during the original hot water supply operation, the second thin tube 16 is required because it is used for both temperature maintenance and freezing prevention. is bumper tube 1
Naturally, a solenoid valve 17 is also required to stop the flow of hot water to the 8 side.

(Effects of the invention) The invention is based on the piping inside the hot water supply unit 1, the hot water tap 8a
By operating the pump 9 and opening the solenoid valve 17 when the hot water temperature drops to the set temperature, such as in the section 8c, an appropriate small amount of hot water is circulated through the piping system, and the tap is opened. At the same time, it is possible to supply high-temperature hot water and to prevent piping from freezing.

Furthermore, by simply connecting the most downstream part A of the hot water supply piping 7 and the hot water supply unit 1 through the hot water return pipe 10 at the point of demand, the hot water supply faucets 8a to 8c can be prevented from freezing, and the hot water faucets 8a to 8c can be prevented from freezing. In usage situations where there is no risk of hot water leaking, even if the hot water return pipe 10 is not connected, the provision of the first thin tube 16 allows for smooth circulation of a small amount of hot water within the hot water unit 1, making it suitable for a wide range of usage situations. It is possible to provide a hot water supply unit that can

[Brief explanation of the drawing]

1 and 2 are a device circuit diagram and an electric circuit diagram according to an embodiment of the present invention, FIG. 3 is a device circuit diagram of a conventional water heater, and FIG. 4 is a hot water tap used in the device shown in FIG. 3. FIG. 2...Hot water storage tank, 3...Hot water pipe, 7...Hot water supply piping, 8a to 8c...Hot water tap, 9...Pump, 1
5... First thin tube, 16... Second thin tube, 17... Solenoid valve, 18... Bypass pipe, 22... Freeze detection means, 26... Connection piping.

Claims (1)

[Scope of utility model registration request] Equipped with a hot water storage tank 2, hot water taps 8a, 8b, 8c
Hot water pipe 3 for connecting hot water pipe 7 connected to
In the hot water unit, a pump 9 is interposed in the hot water pipe 3, and the pump 9 is branched from the hot water pipe 3 on the downstream side of the pump 9 and connected to the hot water storage tank 2. A bypass pipe 18 is provided, a first capillary tube 15 and a second capillary tube 16 are interposed in series in the bypass pipe 18, and a hot water return pipe 10 connected to the most downstream part A of the hot water supply pipe 7 is connected. The connecting pipe 26 is branched from the bypass pipe 18 between the first capillary 15 and the second capillary 16, and a solenoid valve 17 is installed in the bypass pipe 18 between the branch point of the connecting pipe 26 and the hot water storage tank 2. A hot water supply unit characterized in that a control circuit is provided for operating the pump 9 and opening the solenoid valve 17 in accordance with a command from a freeze detection means 22 for detecting freezing.