JP3401857B2 - Water heater - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to hot water storage temperature control of a hot water storage type water heater.

[0002]

2. Description of the Related Art As shown in FIG. 10, a conventional water heater has a hot water storage tank 1 covered with a heat insulating material, and a water inlet pipe 4 extending from a lower portion of the hot water storage tank 1 through a pump 2 to a heater 3 , for example, a heater 3.
A hot water outlet pipe 5 extending from the heater 3 to the upper part of the hot water storage tank 1, a hot water temperature detector 6 for detecting the hot water temperature in the hot water outlet pipe 5, a water supply pipe 7 at the bottom of the hot water storage tank 1, and a hot water supply pipe 8 at the top. ing. Further, 9 is a water temperature detector provided in the water inlet pipe 4.

The operation of the above configuration will be described.
The heater 3 and the pump 2 are energized in a state where the water supplied from the water supply pipe 7 into the hot water storage tank 1 is full, and the water in the hot water storage tank 1 is guided by the pump 2 to the heater 3 via the water inlet pipe 4, The heater 3 heats the hot water, causes the hot water to flow into the upper part of the hot water storage tank 1, and stores the hot water in order from the upper part of the hot water storage tank 1. Here, the difference (DT) between the detected temperature T of the hot water temperature detector 6 provided in the hot water outlet pipe 5 and the hot water temperature set value T1 is multiplied by the water quantity constant to obtain the temperature set value T.
The input voltage of the pump 2 is controlled to be 1. The hot water stored in order from the upper part of the hot water storage tank 1 forms a temperature mixing layer as shown in FIG. 11, and the mixed layer advances toward the lower part of the hot water storage tank 1 as the operating time elapses (dotted line in the figure). When the mixed layer reaches the inlet pipe 4 inlet, the inlet water temperature of the heater 3 rises,
Since the temperature detected by the hot water temperature detector 6 rises, the pump 2
The input voltage is increased to increase the water flow rate and keep the detected temperature constant. After that, when the water temperature detected by the water temperature detector 9 reaches a predetermined value, the heater 3 and the pump 2 are stopped.

[0004]

However, in the above-mentioned conventional configuration, as shown in FIG. 12, when the mixed layer reaches the water inlet pipe 4, the inlet water temperature of the water inlet pipe 4 increases logarithmically, and the input of the pump 2 is accordingly increased. The voltage is increased and the water flow rate Q is increased,
Since the water amount constant is constant with respect to the rise in the inlet water temperature of the water inlet pipe 4, the increase in the amount of water sent by the pump 2 is slow, and the temperature detected by the hot water temperature detector 6 rises beyond the constant control of the hot water temperature, and the heater 3 Exceeding the limit temperature Tmax and heating with the heater 3
Boiling of hot water occurs and reliability decreases. Also, the heater 3
In order to prevent boiling at a temperature lower than the limit temperature Tmax, that is, the detected water temperature of the water temperature detector 9 is low (T in the figure).
When the heater 3 and the pump 2 are stopped in A), there is a problem that the temperature mixing layer remains in the lower part of the hot water storage tank 1 and a predetermined amount of hot water cannot be secured.

The present invention solves the above problems by heating.
It is an object of the present invention to provide a water heater capable of ensuring a predetermined amount of hot water without lowering the reliability of the means .

[0006]

In order to achieve the above object, the present invention provides a hot water storage tank and a heating means from the lower part of the hot water storage tank.
Incoming water pipe and hot water outlet pipe from the heating means to the upper part of the hot water storage tank
If, Pong for circulating water between the hot water tank and heating the hand stage
And a hot water temperature detector that detects the water temperature of the hot water pipe,
It consists of a water temperature detector that detects the water temperature of the pipe and a controller.
The amount of change in the temperature detected by the water temperature detector over a specified period of time
A water heater that changes the circulation flow rate according to.

A second means for solving the problem is a hot water storage tank and the storage
The water inlet pipe from the bottom of the bath to the heating means, and the storage means from the heating means.
Between the hot water outlet pipe reaching the upper part of the hot water tank and the hot water storage tank and the heating means
A pump that circulates the water with the
Water temperature detector and water temperature detector that detects the water temperature of the water inlet pipe
And a controller for detecting the temperature of the hot water temperature detector and
When the difference in the set hot water temperature reaches a specified value, the circulation flow rate changes
Use a water heater to increase the amount.

Further, the controller detects the hot water temperature detector.
When the temperature reaches the set value, stop the heating means and pump.
The water heater according to claim 1 or 2, further comprising a heating source control means.
I am trying.

[0009]

According to the present invention having the above-described structure, the difference (D) between the temperature detected by the hot water temperature detector and the hot water temperature set value by the temperature adjusting means is set.
T) is multiplied by the water volume constant to control the input voltage of the pump
To increase or decrease the amount of water Te, storing hot water at a constant temperature in order from the hot water tank top. After that, when the mixed layer of warm water reaches the water inlet pipe,
The water temperature at the inlet of the water inlet pipe rises faster, and the change amount (DTi) of the temperature detected by the water temperature detector in a predetermined time increases. The circulation flow rate is changed correspondingly .

As described above, when the mixed layer of warm water reaches the water inlet pipe, the amount of water sent by the pump is changed.
Heated hand detecting water temperature is high in hot water increases the reliability can be prevented boil, and the water temperature detector by heating
Since the stage and the pump are stopped, the temperature mixing layer does not remain in the lower part of the hot water storage tank, and a predetermined amount of hot water can be secured.

According to the second means for solving the problem, the mixed layer of the hot water reaches the water inlet pipe, deviates from the constant control of the hot water temperature, and the detected temperature of the hot water temperature detector rises. The difference (DT) between the tapping temperature setting values exceeds a predetermined value. Correspondingly, the amount of change in the circulation flow rate is increased.

In this way, it is judged whether the water has entered the mixed layer of hot water according to the temperature detected by the hot water temperature detector, and the water amount constant is increased so that the amount of water sent by the pump is made to follow so as not to exceed the limit temperature Tmax of the heater. To

[0013]

Embodiments of the present invention will be described below with reference to FIGS.

In FIG. 1, the same reference numerals as those in FIG. 10 of the conventional example indicate the same members and have the same functions, so that the detailed description will be omitted and the different points will be mainly described.

In FIG. 1, reference numeral 10 is a temperature control for controlling the input voltage (V) of the pump 2 by multiplying the difference (DT) between the detected temperature of the hot water temperature detector 6 and the hot water temperature set value by a water quantity constant (W). Reference numeral 11 is a water amount adjusting means for changing the water amount constant from W1 to W4 corresponding to a range (Ti1 to Ti3) of a change amount (DTi) of the temperature detected by the water temperature detector 9 in a predetermined time (TM). , 12 are heating means when the temperature detected by the water temperature detector 9 reaches a predetermined value (TS).
It is a heating source control means for stopping a certain heater 3 and pump 2. Reference numeral 13 is a controller including the above-mentioned means. And
The controller 13 has the specific configuration shown in FIG.

In the above configuration, the operation is performed in step S
It demonstrates based on the control flow of FIG. 2 over 1-S18. In FIG. 2, when the device is turned on (S1), the pump 2 is driven (S2) and the heater 3 is turned on. (S3)
Next, the water temperature detector 9 detects the incoming water temperature TA1 (S4),
A count for a predetermined time (TM) is entered (S5). Next, it is determined whether the predetermined time (TM) has been reached (S6), and if not reached, the hot water temperature detector 6 detects the hot water temperature To (S).
7). Next, To is compared with the first outlet heated water temperature set value T1 (S8), and if To = T1, the incoming water temperature TA1 is compared with a predetermined value (TS) (S9). On the contrary, if they are not equal, the difference between the detected temperature of the hot water temperature detector 6 and the hot water temperature set value (DT)
Is calculated (S10), the input voltage V of the pump 2 is determined by the water amount constant W1 (gradient of the pump voltage V with respect to DT) in FIG. 3, and the pump 2 is controlled (S11).

Next, when the predetermined time (TM) has been reached, the water temperature detector 11 detects the incoming water temperature TA2 again (S12),
The amount of change (DTi) is calculated (S13).

The calculated change amount (DTi) is compared with the set change amounts Ti1 to Ti3 for changing the water amount constant W1 (S14), and D
If Ti ≧ Ti1 to Ti3, enter water temperature TA2 to TA
It is replaced with 1 (S15), and the process goes to S7. Next, in S9, it is judged whether the incoming water temperature TA1 is the heating source stop temperature TS, and if it is not TS, the process returns to S5.

In a normal operation state (a state in which the hot water mixing layer in the hot water storage tank 1 does not reach the water inlet pipe 4), S5 → S6 → S7 → S8 → (S10 → S11) → S9 in the flow chart.
→ S5 or S5 → S6 → S12 → S13 → S14 → S
15->S7->S8->(S10->S11)->S9-> S5, and hot water of the constant temperature T1 discharged from the hot water discharge pipe 5
It is stored in order from the top.

When the hot water mixed layer in the hot water storage tank 1 reaches the water inlet pipe 4, the water inlet temperature TA2 detected by the water temperature detector 9 rises, the change amount (DTi) per predetermined time (TM) rises, and DTi ≧ Ti1 to Ti3 (S14), and as shown in FIG. 4, the water amount constant W1 is sequentially changed from W2 to W4 so as to correspond to the change amounts Ti1 to Ti3. (S16) As shown in FIG. 3, when the water amount constant is changed (W2 to W4), the change amount of the pump voltage V with respect to the DT value becomes large.

Therefore, when the hot water mixing layer in the hot water storage tank 1 reaches the water inlet pipe 4, S5 in the flow of FIG.
→ S6 → S7 → S8 → (S10 → S11) → S9 → S5
Or S5 → S6 → S12 → S13 → S14 → S16 →
S15 → S7 → S8 → (S10 → S11) → S9 → S5
The above loop is repeated to change the water amount constant to W4. If the water temperature constant is changed to W4 and the incoming water temperature TA1 detected by the water temperature detector 9 further rises, and TA1 = TS (S
9) Stop the heater 3 and the pump 2. (S17, S1
8) The controller 13 performs the above operation.

According to the structure of this embodiment, as shown in FIG. 5, the fact that the hot water mixing layer in the hot water storage tank 1 has reached the water inlet pipe 4,
Time axis (TM) and amount of change in inlet pipe inlet water temperature (Ti1 to T
Increase the water content constant while monitoring in i3) (W2-
By W4), the amount Q of water sent by the pump is made to follow.
Repeating this operation, the temperature T detected by the water temperature detector 9
When A1 reaches the maximum incoming water temperature set value TS, the heater 3,
By stopping the pump 2, the heater 3 inlet water temperature is T
It is possible to operate up to a temperature TS higher than A, the temperature mixing layer is less likely to remain in the lower part of the hot water storage tank 1, a predetermined amount of hot water can be secured, and the amount of water Q sent by the pump 2 is made to follow, and the limit temperature Tm of the heater 3
The reliability is improved by not exceeding ax and preventing boiling of warm water heated by the heater 3.

Next, a second embodiment of the present invention will be described with reference to FIGS.
This will be described with reference to FIG.

In FIG. 6, the same reference numerals as those in the first embodiment of FIG. 1 indicate the same members and have the same functions, and therefore a detailed description thereof will be omitted, and different points will be mainly described.

From FIG. 6, reference numeral 10 is a temperature control for controlling the input voltage (V) of the pump 2 by multiplying the difference (DT) between the detected temperature of the hot water temperature detector 6 and the hot water temperature set value by the water quantity constant (W). In the means, 14 has a plurality of water quantity constants (W1 to W4), and when the difference (DT) between the temperature detected by the hot water temperature detector 6 and the hot water temperature set value (DT) exceeds a predetermined value (DT1), the water quantity constant Is a water amount adjusting means for sequentially increasing, and 15 is a heating source control means for stopping the heater 3 and the pump 2 when the temperature detected by the hot water temperature detector 6 reaches a set value (TE). Reference numeral 16 is a controller including the above-mentioned means. And the controller 15
Has a specific arrangement shown in FIG.

In the above configuration, the operation is processed S19.
It demonstrates based on the control flow of FIG. In FIG. 7, when the device is turned on (S19), the pump 2 is driven (S20) and the heater 3 is turned on. (S2
1) Next, the hot water temperature detector 10 detects the hot water temperature To1 (S22) and compares the hot water temperature setting value T1 with the hot water temperature set value T1.
If o1 = T1, the process returns to S22. Conversely, if not equal, To1 is compared with the set value TE. (S23, 24) To
If not 1 = TE, the difference (DT) between To1 and the outlet heated water temperature set value T1 is calculated (S25), and DT is compared with a predetermined value DT1 for changing the water amount constant W1 (S26). The input voltage V of the pump 2 is obtained by the water amount constant W1 (gradient of the pump voltage V with respect to DT), the pump 2 is controlled (S27), and the process returns to S22.

In a normal operation state (a state in which the hot water mixing layer in the hot water storage tank 1 does not reach the water inlet pipe 4), S22 → S23 → S24 → S25 → S26 → S27 → in the flow chart.
S22 or S22 → S23 → S22, and the hot water outlet pipe 5
Hot water having a constant temperature T1 discharged from the hot water storage tank 1 is sequentially stored from the upper portion of the hot water storage tank 1.

When the hot water mixing layer in the hot water storage tank 1 reaches the water inlet pipe 4, the inlet water temperature of the water inlet pipe 4 increases logarithmically, deviating from the constant control of the hot water temperature T1 and detected by the hot water temperature detector 6. To1 rises and the difference between To1 and the hot water temperature setting value (DT)
Exceeds a predetermined value (DT1) (S26), the water amount constant W1 is changed to W2. (S28) As shown in FIG. 8, when the water amount constant is changed (W1 → W2), the pump voltage V with respect to the DT value increases from V1 to V2.

Therefore, when the hot water mixing layer in the hot water storage tank 1 reaches the water inlet pipe 4, S2 in the flow of FIG.
2 → S23 → S24 → S25 → S26 (→ S28) → S
The loop of 27 → S22 or S22 → S23 → S22 is repeated to change the water amount constant to W4.

By changing the water amount constant to W4, the detected hot water temperature To1 of the hot water temperature detector 10 further rises, and To1 =
When it becomes TE (S24), the heater 3 and the pump 2 are stopped (S29, S30). The above operation is performed by the controller 13.

According to the structure of this embodiment, as shown in FIG. 9, the fact that the hot water mixing layer in the hot water storage tank 1 has reached the water inlet pipe 4,
By monitoring the detected hot water temperature To1 of the hot water temperature detector 6 and increasing the water quantity constant (W2 to W4),
Follow the amount Q of water sent by the pump. By repeating this operation, when the hot water temperature To1 detected by the hot water temperature detector 6 reaches the maximum hot water temperature set value TE, the heater 3 and the pump 2 are stopped, whereby the heater 3 inlet water temperature can be operated to a higher temperature. The temperature mixing layer is less likely to remain in the lower part of the hot water storage tank 1, a predetermined amount of hot water can be secured, and because the hot water temperature detector 6 monitors the temperature, it is possible to reliably control the temperature so as not to exceed the limit temperature Tmax of the heater 3. The boiling of hot water heated in 3 can be prevented.

[0032]

As described above, the water heater of the present invention is
The water temperature at the inlet of the heating means can be operated to a higher temperature, the temperature mixing layer is less likely to remain in the lower part of the hot water storage tank, a certain amount of hot water can be secured, and reliability is improved by preventing boiling of the hot water heated by the heating means. To do.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a water heater according to an embodiment of the present invention.

FIG. 2 is a control flowchart of the water heater.

FIG. 3 is a characteristic diagram showing a relationship between a difference (DT) between a detected temperature of a hot water temperature detector of the same water heater and a hot water temperature set value and a pump input voltage (V).

FIG. 4 is a characteristic diagram showing a relationship between a change amount (DTi) of a temperature detected by a water temperature detector of the same water heater in a predetermined time and a water amount constant W.

FIG. 5 is a characteristic diagram showing the relationship between time, temperature, and water volume of the water heater.

FIG. 6 is a configuration diagram of a water heater according to another embodiment of the present invention.

FIG. 7 is a control flowchart of the water heater.

FIG. 8 is a characteristic diagram showing the relationship between the detected temperature of the hot water temperature detector of the water heater and the difference (DT) between the hot water temperature set values and the pump input voltage (V).

FIG. 9 is a characteristic diagram showing the relationship between time, temperature, and water volume of the water heater.

FIG. 10 is a configuration diagram of a conventional water heater.

FIG. 11 is a characteristic diagram showing a hot water tank height and a hot water tank temperature of a conventional water heater.

FIG. 12 is a characteristic diagram showing the relationship between time, temperature, and water volume of a conventional water heater.

[Explanation of symbols]

1 hot water storage tank 2 pumps 3 heater 4 water pipe 5 Hot water pipe 6 Hot water temperature detector 9 Water temperature detector 10 Temperature control means 11, 14 Water volume control means 12, 15 Heating source control means 13, 16 controller

─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shinji Miyauchi 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) Reference JP-A-3-211359 (JP, A) JP-A-60- 164157 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) F24H 1/18 302 F24H 1/00 611

Claims (3)

(57) [Claims] 1. A hot water storage tank, a water inlet pipe extending from a lower portion of the hot water storage tank to a heating means , a hot water outlet pipe extending from the heating means to an upper portion of the hot water storage tank, and a pump for circulating water between the hot water storage tank and the heating means.
And flop, and hot water temperature detector for detecting the temperature of the hot water pipe, a water temperature detector for detecting the temperature of the water inlet pipe, made of the controller, before <br/> SL temperature predetermined time water temperature detector for detecting Amount of change
Water heater to vary the circulation flow rate in response to. 2. A hot water tank, the hot water storage tank water inlet pipe leading to the bottom by Ri heating means, a hot water pipe extending from the heating means to the hot water tank top, pump for circulating the water between the hot water tank and the heating means When the hot water temperature detector for detecting the temperature of the hot water pipe, a water temperature detector for detecting the temperature of the water inlet pipe, made of the controller, before
When the difference between the detected temperature and the hot water temperature set value of the serial temperature water temperature detector reaches a predetermined value, water heater to increase the amount of change in circulation flow rate. 3. The controller sets the temperature detected by the hot water temperature detector.
Heating source control that stops the heating means and pump when the set value is reached.
The water heater according to claim 1 or 2, further comprising a control means .