JPS63204064A - Instantaneous feeding type hot water feeder - Google Patents

Abstract

PURPOSE:To cause a set temperature under a preheating condition for use in performing an instantaneous feeding of hot water to be varied with temperature of fed water toward a hot water feeder and to keep the set temperature always at a value higher than a hot temperature side of water temperature by a method wherein a first sensor for sensing a temperature at an outlet part of a thermal suction part, a second sensor inserted into a water circuit for use in sensing the temperature of water fed into, or coming from, a hot water feeder and means for comparing and calculating signals of sensed temperature of both sensors. CONSTITUTION:Under a condition that a tap water port 2 is closed and a hot water feeding operation is stopped, a closing circuit bridging over a heat exchanger and a part near the tap water port is circulated and heated under cooperation of a heating means and a pump P. At this time, temperature of fed water for the hot water feeder is sensed by a second sensor 62, hot water temperature at an outlet part of a heat suction part is sensed by a first sensor 61, these temperatures are compared and calculated by a comparing and calculating means C. When a difference in temperature is decreased below a predetermined level, a desired output signal from the means C is generated and then the pump P and the heating means are made operative. When hot water temperature of the closed circuit communicating the heat suction part of the heat exchanger with the tap water port is increased as compared with the water temperature by a specified temperature, circulation heating is terminated and this operation is subsequently repeated.

Description

[Detailed Description of the Invention] [Field of Application] The present invention relates to a water heater, particularly a stop-start type water heater,
When the appliance is ready for use (in the case of a pilot ignition type, the pilot ignition has been completed, and in the case of a direct ignition, the power has been turned on), hot water at a certain temperature will be drawn at the same time as the hot water starts. This relates to a so-called instantaneous hot water supply type water heater. In addition, the circulation circuit from the heat exchanger formed for instant hot water dispensing to the hot water faucet is maintained at a constant temperature higher than the temperature of the water entering the heat exchanger (water heater), so that the water temperature fluctuates. However, when the hot water is re-discharged, hot water that always feels warm can be obtained, and unnecessary preheating can be prevented.

[Prior art and its problems] As an instant hot water heater as described above,
This is proposed in Japanese Utility Model Application Publication No. 59-180231, and as shown in FIG. 2) is also connected to the water circuit (14) on the upstream side of the heat absorption pipe (10) via the communication pipe (12), and when the faucet (2) is closed, the combustion of the burner (3) and the communication pipe ( 12
) A loop-shaped circulation circuit consisting of an endothermic pipe (10), a hot water supply pipe (11), and a communication pipe (12) is circulated and heated by the pump (P) inserted in the pipe (P), and the inside of this circulation circuit is maintained at a predetermined temperature.

Therefore, even if hot water is resumed after a certain period of time has passed after the faucet (2) is closed and hot water is stopped, there is an advantage that hot water can be quickly obtained.

However, with this conventional system, the water temperature is set at a constant temperature when the hot water is re-discharged, so changes in the water temperature entering the water heater due to seasonal changes may cause the water temperature to be too hot when the hot water is re-discharged. , too lukewarm. The warmth of hot water that people feel is greatly affected by the outside temperature and water temperature, and even at a constant temperature,
It feels lukewarm in the summer, but feels warm in the winter. This is because a person's sensible temperature is determined by the temperature difference between the outside air temperature and the water temperature.

[Technical Problem] The present invention has been made in view of the above points, and it is possible to communicate and connect the vicinity of the faucet (2) connected to the r water supply pipe (11) and the heat absorption part through the communication pipe (12). and insert a circulation pump (P) into the communication pipe (12), and when hot water supply is stopped, operate the pump and heating means,
In the water heater J, the closed circuit consisting of the heat absorption part and the hot water supply pipe (11) and the connecting pipe (12) is heated in circulation as needed so that the inside of the closed circuit reaches a predetermined temperature. The technical problem is to change the set temperature in the preheating state for the water heater according to the temperature of the water entering the water heater, so that the temperature is always maintained at a constant temperature higher than the water temperature.

[Technical Means] The technical means of the present invention taken to solve the above technical problem includes a first sensor (61) that detects the temperature on the outlet side of the r heat absorption section, and a first sensor (61) that is inserted into the water circuit (14). In addition, a second sensor (62) that detects the temperature of water entering the water heater, and a second sensor (
62) and the temperature signal detected by the first sensor (61), and outputs a circulating heating signal when the difference in signal level between these two signals falls below a certain level (C); and this comparison calculation means (C)
The pump (P) and the heating means are operated by the circulating heating signal from the pump (see Fig. 1).

[Effect] The above technical means of the present invention operates as follows.

When the faucet (2) is closed and hot water supply is stopped, the closed circuit connecting the heat exchanger aH and the vicinity of the faucet is circulated and heated by the cooperation of the heating means and the pump (P), similar to the conventional example described above. .

At this time, the water temperature on the outlet side of the large-scale heating section to the water heater is the first
Detected by a sensor (61). Then, the temperatures at these two locations are compared and calculated by the comparison calculation means (C), and when the temperature difference between them falls below a certain level, a predetermined output signal is generated from the comparison calculation means (C),
Both the pump (I') and the heating means are in operation. As a result of this circulating heating, when the temperature of the hot water in the closed circuit connecting the heat absorption part of the heat exchanger and the faucet reaches a certain temperature increase relative to the incoming water temperature, the circulating heating is stopped, and this operation is stopped from now on. return. In this way, the water temperature in the closed circuit is always
It will be maintained at a certain level higher than the incoming water temperature.

Next, when hot water is resumed, hot water maintained at a predetermined temperature as described above can be drawn from the faucet, and hot water heated to a predetermined temperature by the heat exchanger can then be drawn continuously. becomes.

[effect] has.

The hot water temperature in the closed circuit that connects the heat absorption part of the heat exchanger and the faucet is always maintained at a certain level higher than the incoming water temperature, regardless of changes in the incoming water temperature. It always feels moderately warm and is easy to use.

Also, regardless of changes in the water temperature entering the water heater, the preheating temperature is always maintained at an appropriate temperature that is a certain level higher than the large water temperature, so it is important to keep the preheating temperature higher than necessary. This prevents unnecessary energy consumption.

[Example] The first example shown in Figs. 2 to 4 employs a three-way switching valve (41) to switch between the hot water supply circuit when the water heater is in operation and the circulation heating circuit when the water heater is stopped. Then, the outlet side of the endothermic tube (lO) and the communication tube (12) are communicated through a bypass circuit (13), and this bypass circuit (
13) and the connecting pipe (12), the three-way switching valve (
41) is inserted, a check valve (15) is inserted into the water circuit section upstream from the confluence of the communication pipe (12) and the water circuit (14), and the three-way switching valve (41) in the communication pipe (12) is inserted. ) and the water circuit (14), a pump (P) and an auxiliary heater (11) as heating means are inserted.

In addition, in order to automate the operation of the three-way switching valve (41) and the pump (P), the connecting pipe (12) in the water circuit (14) is
) A water flow switch (16) and a second sensor (62) are inserted upstream of the confluence with the water flow switch (16).
6) detects the opening and closing of the faucet (2), and also detects the opening and closing of the faucet (2).
A sensor (62) detects the temperature of water entering the heat exchanger. Further, on the outlet side of the heat absorption pipe (10) as the heat absorption part described above, a first sensor (61
) is provided. These, water flow switch (18),
1st. The second sensors (61), (82), the three-way switching valve (41) as the output operation unit, and the pump (Pl) are as follows:
Electrically, they are related as shown in FIG.

The three-way switching valve (41) is normally energized so that the bypass circuit (13) and the communication pipe (12) are in communication with each other, and the coil (42) serving as the electrical drive source is in a conductive state. Then, as shown in Figure 3, the bypass circuit (13
) and the communication pipe (12) are cut off, and the pump (P) side and the faucet (2) side of the communication pipe (12) are configured to communicate with each other.

This coil (42) is connected in parallel with the pump (P) and the auxiliary heater (+1), both of which are connected to the comparison calculation means (C) consisting of the operational amplifier circuit (51) and the comparator (52). It is controlled by the output and also by the output signal of the water flow switch (+6). In addition, here, the operational amplifier circuit (
51) is for calculating the difference between the voltage level corresponding to the temperature detected by the first sensor (61) and the voltage level corresponding to the temperature detected by the second sensor (62). ) becomes one input of the comparator (52). Also, a comparison reference voltage setting circuit (53)
This comparison reference voltage is set to correspond to the difference between the circulating heating temperature and the large water temperature. The output from this comparator (52) is the output from the pump (
The voltage is applied to the base of a switching transistor serving as a switch means (54) inserted in a circuit such as P).

Therefore, in this embodiment, normally, when the faucet (2) is opened, a water flow is generated on the water circuit (14) side.
The normally closed water flow switch (16) opens and the electrical circuit to the parallel circuit of the three-way switching valve (41) and pump (P) is cut off. It is in a stopped state. At this time, the three-way switching valve (41) is in the state shown in Figure 2, and the hot water from the heat absorption pipe (10) of the heat exchanger (1) is transferred to the hot water supply pipe (11) and the communication pipe ( 12) to the faucet (2), where hot water is supplied.

Next, when the faucet (2) is closed, the flow in the water circuit (14) is stopped and the water flow switch (16) is closed. The switch means (54) to which the output of (C) is manually operated is not in a conductive state, and at this point, the three-way switching valve (41), the pump (P), and the auxiliary heater (11) are in a non-conductive state. .

Thereafter, when the temperature detected by the first sensor (61) becomes equal to or lower than the set temperature, the switch means (54) becomes conductive, connecting the three-way switching valve (41), the pump (P), and the auxiliary heater (
1 () are both in the operating state, and the three-way switching valve (41) is
As shown in Figure 3, the bypass circuit (13
) to the communication pipe (12), the circuit from the faucet (2) in the communication pipe (12) to the water circuit (14) is opened, and the pump (P) starts operating. Furthermore, the auxiliary heater (11) becomes in a heat generating state, and the water in the closed circuit of the heat absorption pipe (10), the hot water supply pipe (11), and the communication pipe (12) is circulated and heated, and the instant hot water temperature is always maintained. becomes.

In particular, in this embodiment, when hot water is supplied, hot water is supplied through two circuits: one leading to the faucet via the bypass circuit (13) and the connecting pipe (12), and the other through the hot water supply pipe (11). Therefore, even if the circuit cross sections of the hot water supply pipe (11) and the communication pipe (12) are set small in advance, a sufficient hot water supply flow rate can be ensured. Therefore, in a water heater of the type that forms a closed circuit for instant hot water dispensing, there is an advantage that the piping cross section from the heat absorption part to the faucet can be set small.

Next, in the second embodiment shown in FIG. 5, a burner (3) is also used as a heating means for circulating heating, and a first shutoff valve (4) is installed in a bypass circuit (13) for switching between hot water supply and circulation.
5), a second shutoff valve (44) is inserted between the confluence of the bypass circuit (13) and the communication pipe (12) and the pump (P).

In this embodiment, as shown in FIG.
6) normally closed contact is pump (P), No. 211! Danben (4)
4) and a solenoid valve (31) inserted in the circuit to the gas burner
The normally closed contact of the water flow switch (16) is inserted between the parallel circuit consisting of the electromagnetic valve (31) and the first cutoff valve (45), and the switch means (54). It is inserted between the switch means (54).

Therefore, when hot water is supplied, the solenoid valve (31) and the first shutoff valve (4)
Only the solenoid valve (31) is opened during circulating heating.
And only the second shutoff valve (44) opens. In this case, the operation is the same as in the first embodiment, and during circulation heating, the pump (P
) and the burner (3) work together to maintain a closed circuit connecting the heat absorbing part and the faucet (2) at a predetermined temperature.

Note that if the passage resistance of the pump (P) in the stopped state is extremely large, the second shutoff valve (44) may not be provided.

Moreover, regardless of whether or not the second shutoff valve (44) is provided,
The first cutoff valve (45) functions similarly to the above case as a check valve that only allows water to flow from the bypass circuit (13) to the communication pipe (12).

In addition, in each of the embodiments described in detail above, the heat exchanger (1)
In addition, as shown in Figure 7, the hot water supply pipe (11), i! Changing the piping configuration so that a plurality of combinations of li-junction pipes (12) are provided can be appropriately adopted as necessary. In addition, in any of the above embodiments, the hot water supply pipe (1
There is no difference in the fact that the parallel piping of 1) and the connecting pipe (12) can be made smaller compared to the conventional example described above.

In addition, many recent water heaters incorporate a proportional control valve so that the hot water temperature can be set arbitrarily within the range of 35°C to 85°C using a hot water temperature setting device. The present invention can also be implemented in water heaters.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram of the principle of the present invention, and Figure 2 is a diagram explaining the principle of the present invention.
An explanatory diagram of the embodiment, FIG. 5 is an explanatory diagram of the second embodiment, FIG. 6 is an electric circuit diagram thereof, FIG. 7 is an explanatory diagram of the third embodiment, and FIG.
The figure is an explanatory diagram of a conventional example, and in the figure, (10) ... heat absorption pipe (11) ... hot water supply pipe (12)
...Connection pipe (13) ...Bypass circuit (14)
... Water circuit (2) ... Faucet (61) ... First sensor (62) ... Second sensor (C) ... Comparison calculation means

Claims (1)

[Claims] The vicinity of the faucet (2) connected to the hot water supply pipe (11) and the heat absorbing part are connected through a communication pipe (12), and a circulation pump (P) is inserted into the communication pipe (12) to supply hot water. In the stopped state, the pump and the heating means are operated to maintain the closed circuit as necessary so that the inside of the closed circuit consisting of the heat absorption part, the hot water supply pipe (11) and the communication pipe (12) reaches a predetermined temperature. In a water heater configured to perform circulating heating, a first sensor (61) detects the temperature on the outlet side of the heat absorption part;
A second sensor (62) is inserted into the water circuit (14) and detects the temperature of water entering the water heater, and the detected temperature signal of the second sensor (62) is compared with the detected temperature signal of the first sensor (61). and a comparison calculation means (
C), and the pump (P) and the heating means are operated by the circulating heating signal from the comparison calculation means (C).