JPH0765809B2 - Oil water heater control method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is a petroleum hot water supply system capable of supplying hot water having a preset hot water supply temperature with little temperature hunting by mixing hot water discharged from an instantaneous heat exchanger with a bypass. The purpose is to provide a method of controlling the vessel.

[0002]

2. Description of the Related Art Conventionally, there has been provided a petroleum water heater for supplying a predetermined amount of hot water by supplying petroleum fuel to an instantaneous heat exchanger by on / off cycle driving by an electromagnetic pump.

[0003]

However, in the above-mentioned instantaneous heating type oil water heater using the electromagnetic pump, since the electromagnetic pump supplies the petroleum fuel in the on / off cycle, the combustion in the burner is the maximum. Combustion (when the pump is on) and no combustion (when the pump is off) are repeated. That is, when the electromagnetic pump is turned on, the temperature of the hot water discharged from the instantaneous heat exchanger rises sharply, and when the electromagnetic pump is turned off, the temperature of the hot water sharply drops, which causes the hot water supply temperature to hunt in a cycle similar to the on / off cycle of the pump. there were.

In view of the above, the present invention solves the above-mentioned drawbacks of the prior art, and in an oil water heater in which oil fuel is supplied by an electromagnetic pump in an on-off cycle and heated by an instantaneous heat exchanger to supply hot water, the electromagnetic pump is turned on and off. An object of the present invention is to provide a control method capable of smooth and stable hot water supply without causing hunting of the hot water supply temperature due to the fuel supply cycle.

[0005]

In order to achieve the above-mentioned object, a method for controlling an oil water heater according to the present invention is to heat water from an inlet channel with an instantaneous heat exchanger to discharge the hot water into the outlet channel, The bypass from the water channel is connected to the hot water channel so that water can be mixed by the water mixing valve. When the set hot water supply temperature T _MS is set, the heat exchanger set hot water temperature T _KS and the incoming water temperature T _C are set. wherein the heat exchanger water inlet flow rate R _KO calculates the necessary heat quantity Q _KO instant heat exchanger, the computed heat exchanger required quantity of heat Q _KO
The feed-on supply of petroleum fuel is started by calculating the on-time and off-time of the corresponding fuel supply electromagnetic pump, and at the same time the current heat exchanger outlet hot water temperature is at least shorter than the on-off cycle of the fuel supply electromagnetic pump. T _K
From the current hot water supply temperature T _M and the current incoming water temperature T _C , the current water mixing rate K _BK by the water mixing valve, the preset hot water supply temperature T _MS and the current heat exchanger outlet hot water temperature T _K, and the current time The target water mixing ratio K _BKS required by the water mixing valve to obtain the set hot water supply temperature T _MS from the water input temperature T _C is calculated, and the difference between the target water mixing ratio K _BKS and the current water mixing ratio K _BK is calculated. It is characterized in that the water mixing valve is feedback-adjusted by an amount corresponding to.

[0006]

According to the features of the method of the present invention, when the hot water supply temperature is set and the hot water supply scallop is opened, the heat exchanger set outlet water temperature T _KS , the incoming water temperature T _C, and the incoming heat flow rate of the heat exchanger are determined. The required heat quantity Q _KO of the instant heat exchanger is calculated from R _KO, and the on-time and off-time of the corresponding fuel supply electromagnetic pump are further calculated from the calculated heat exchanger necessary heat quantity Q _KO . Then, the electromagnetic pump is feedforward-controlled in the calculated on / off cycle. When hot water supply is actually started, the target water mixture ratio K _BK and the target hot water supply temperature T _MS required by the water mixing valve to reach the current water mixture ratio K _BK and the set hot water supply temperature T _MS are generated at least in each cycle shorter than the ON / OFF cycle of the fuel supply electromagnetic pump. The water rate K _BKS is calculated, and the calculated target water mixing rate K
The goal to be the _BKS drinking-water ratio K _BKS and the current mixing water rate K
_The water mixing valve is feedback-adjusted by an amount corresponding to the difference from _BK . The current water mixing ratio K _BK is set to a predetermined set hot water temperature T every cycle shorter than the on / off cycle of the fuel supply electromagnetic pump.
_Since the target water mixing ratio K _BKS for achieving _MS is adjusted, the hunting peaks and valleys of the tapping temperature due to the on / off cycle supply of oil by the electromagnetic pump are offset, and hot water with a smoother and more stable set hot water supply temperature is supplied. be able to.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an overall configuration diagram of an oil water heater in which the method of the present invention is implemented, FIG. 2 is a sectional view showing an example of the structure of a water mixing valve, and FIG. Fig. 4 shows the amount of mixed hot water R _K from the heat exchanger and the amount of mixed water R _B from the bypass.
FIG. 4 is a diagram showing a relationship between the hot water supply temperature T _K from the heat exchanger, the bypass water temperature T _C, and the hot water supply temperature T _M after mixing water with each other.

In the oil water heater shown in FIG. 1, the water inlet 10
The supplied water is heated by the instant heat exchanger 20
It is bathed in 30. A bypass 40 is connected to the hot water outlet 30 from the water inlet 10 via a water mixing valve 70, and hot water mixed in the hot water supply passage 50 is supplied. Inlet 10
An inlet water temperature sensor 11 and an inlet water flow rate sensor 12 are provided at a position downstream of the branch point of the bypass 40. Further, the instantaneous heat exchanger 20 is provided with a gun type oil burner 21. The gun-type oil burner 21 is burned by being sprayed with petroleum fuel by a fuel supply electromagnetic pump (not shown). The fuel supply electromagnetic pump sends fuel at a predetermined flow rate by supplying fuel in an on / off cycle. The hot water outlet 30 is provided with a small capacity mixing tank 31 and a hot water outlet temperature sensor 32 for mixing the hot water before and after hot water discharged from the instantaneous heat exchanger 20, and the hot water supply passage 50.
A hot water supply temperature sensor 51 and an overflow prevention device 52 are provided in the. Reference numeral 60 is a controller with a built-in microcomputer for controlling the entire water heater, which inputs information from each sensor 11, 12, 32, 51, 52 and a command from the remote controller 80, performs a calculation according to a predetermined program, and outputs the fuel (not shown). It outputs control signals to the supply electromagnetic pump, oil burner 21, mixed water valve 70, and other parts.

In FIG. 2, the water mixing valve 70 includes a shaft 73, a shaft 73 rotated by a stepping motor 72, and a shaft 73.
A pair of valve bodies 74, 75 that are moved by the rotation of 73 are arranged. By changing the angle of the stepping motor 72, the hot water passage port 76 and the water passage port by the pair of valves 74, 75 are arranged.
Changing the 77 passage resistance, it is possible to change the mixing water ratio K _BK. This water mixing ratio K _BK and the angle of the stepping motor 72 have a one-to-one correspondence, and the current water mixing ratio K _BKO and the target water mixing ratio K
_{If BKS} is known, the target water mixing ratio K _BKS and the current water mixing ratio K _BK
The difference can be calculated as the control angle of the stepping motor 72, and adjustment control can be performed.

Next, a method of hot water supply control by the controller 60 will be described with reference to FIG. Now, when the hot water supply lantern (not shown) of the hot water supply passage 50 is opened while the pilot fire is lit (Yes in S1), water is supplied through the water supply passage 10 and the amount of water equal to or higher than the minimum working water is detected by the input flow rate sensor 12 Is detected (Yes in S2), the combustion of the burner 21 is started. At this time, when the user sets the set hot water supply temperature T _MS , the controller 60 firstly causes the heat exchanger set hot water temperature T _KS , the incoming water temperature T _C by the incoming water temperature sensor 11 and the incoming water flow rate sensor 12 to be predetermined. Heat exchanger water input flow rate R _KO
From the above, the required heat quantity Q _KO of the instantaneous heat exchanger 20 per unit time is calculated by the following equation 1 (S3). The required heat quantity Q _KO may be divided by 25 to obtain the required number.

[0011]

[Equation 1] Q _KO = (T _KS −T _C ) · R _KO Q _KO : Required heat amount of the instantaneous heat exchanger 20 T _KS : Predetermined heat exchanger set hot water temperature T _C : Inlet water temperature R _KO : Heat Exchanger incoming water flow rate

Further, the controller 60 further calculates the on-time and off-time of the corresponding fuel supply electromagnetic pump from the calculated heat exchanger required heat quantity Q _KO (S4), and at the calculated on-off cycle, the electromagnetic pump Performs feedforward control (S5). The on-time and the off-time of the fuel supply electromagnetic pump are calculated from the ratio of the calculated heat exchanger required heat quantity Q _KO to the heat generation quantity (greater than the necessary heat quantity Q _KO ) at the time of maximum oil supply by the fuel supply electromagnetic pump. can do.

When hot water supply is actually started, at least every predetermined cycle (S6) which is shorter than the on / off cycle of the fuel supply electromagnetic pump, the current water mixing rate K _BK by the water mixing valve 70 and the set hot water supply. A target water mixing rate K _BKS required to reach the temperature T _MS is calculated (S7). Explaining how to calculate the current water mixing ratio K _BK and the target water mixing ratio K _BKS , first, the water mixing amount from the bypass 40 side based on the current water mixing ratio K _BK is R _B , and from the instantaneous heat exchanger 20 side. If the amount of mixed hot water is R _K , the following equations 2 and 3 hold.

[0014]

[Number 2] _{(T M -T C) · (} R B + R K) = T K · R K T M: moment of the hot water supply temperature T _C: incoming water temperature T _K: heat exchanger current tapping temperature R _B: Currently water mixture R _K from the bypass 40 side in: mixing water amount of hot water from the heat exchanger 20 side of the current

[0015]

Equation 3] _{K BK = R B / R K} K BK: water mixture ratio of current R _B: water mixture R _K from the bypass 40 side at the moment: water mixture of hot water from the heat exchanger 20 side of the current

From the equations 2 and 3, the current water mixing ratio K _BK
Is obtained by the following equation 4.

[0017]

Equation 4] _{K BK = R B / R K} = (T K -T M) / (T M -T C) K BKS: target water mixture ratio K _BK: water mixture ratio at the present time T _K: heat exchange current Hot water supply temperature T _M : Hot water supply temperature at present T _C : Inlet water temperature

Similarly, the target water mixing ratio K _BKS can be obtained by the following equation 5.

[0019]

Equation 5] _{K BKS = (T K -T MS} ) / (T MS -T C) K BK: water mixture ratio at the present time T _MS: set hot water supply temperature T _K: heat exchanger current tapping temperature T _C: water inlet temperature

Then, the controller 60 calculates an amount corresponding to the difference between the target water mixing ratio K _BKS and the current water mixing ratio K _BK so that the calculated target water mixing ratio K _BKS will be obtained, and the calculated amount will be mixed. Feedback-adjust the water valve 70. Actually, the controller 60 calculates the difference between the rotation angle of the stepping motor 72 corresponding to the target water mixing ratio K _BKS and the rotation angle of the stepping motor 72 corresponding to the current water mixing ratio K _BK as the control angle ( S8), stepping motor 72 by the control angle
Is controlled (S9).

By performing the hot water supply control as described above, as shown in FIG. 4, the amount R of mixed hot water from the instantaneous heat exchanger 20.
_K and the mixed water amount R _B from the bypass 40 are
When the temperature is high, the amount of water R _B is large and the amount of hot water R _K is small, and when the temperature is low, the amount of water R _B is small and the amount of hot water R _K is large. Therefore, the hunting peaks and valleys of the hot water discharged from the instantaneous heat exchanger 20 are canceled and the hot water flowing out to the hot water supply passage 50 becomes a very smooth and stable hot water having the set hot water supply temperature.

The hot water supply control method as described above may be performed in all modes of the hot water supply operation, or depending on the mode of use of the water heater, hunting of the hot water temperature is not particularly desired. You may make it limited to the use mode of. For example, in the hot water supply operation, in the high temperature use mode, the bypass water mixture by the water mixture valve 70 is fully closed to only the hot water discharged from the instantaneous heat exchanger 20, and in the shower use mode, the hot water supply control method of the present invention is used. In other cases (usually general hot water supply), there is a method of use in which the water mixing rate by the water mixing valve 70 is kept constant. By such a method of use, deterioration of durability due to frequent control of the water mixing valve 70 is prevented, and in a mode in which temperature hunting is not preferred, hot water with a very smooth temperature without hunting can be reliably supplied. it can.

[0023]

According to the method of controlling an oil water heater according to the present invention, the present invention has the above-described structure and operation. At least a period shorter than the on / off period of the fuel supply electromagnetic pump, the present mixing time is set. Since the water ratio K _BK is adjusted to the target water mixing ratio K _BKS to reach the predetermined set hot water temperature T _MS , the hunting peaks and valleys of the hot water discharge temperature due to the on / off cycle supply of oil by the electromagnetic pump are offset and smoother. It is possible to supply hot water with a stable set hot water supply temperature. In addition, even if the hot water outlet temperature from the instantaneous heat exchanger changes significantly due to a large change in the flow rate, the water mixing ratio is immediately changed by the water mixing valve, reducing the effect on the hot water supply temperature. be able to. Further, even when the set hot water supply temperature is significantly changed, the temperature change can be quickly dealt with by immediately changing and adjusting the water mixing ratio by the water mixing valve.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of an oil water heater in which the method of the present invention is implemented.

FIG. 2 is a cross-sectional view showing a structural example of a water mixing valve.

FIG. 3 is a flowchart showing an example of control by the method of the present invention.

FIG. 4 shows the relationship between the amount R _K of mixed hot water from the heat exchanger and the amount R _B of mixed hot water from the bypass side, and the temperature T _K of hot water discharged from the heat exchanger.
FIG. 5 is a diagram showing a relationship between a mixed water temperature (inlet temperature) T _C from the bypass side and a hot water supply temperature T _M after mixed water.

[Explanation of symbols]

 10 Inlet channel 11 Inlet temperature sensor 12 Inlet flow rate sensor 20 Instantaneous heat exchanger 21 Gun type oil burner 30 Outlet channel 32 Outlet temperature sensor 40 Bypass 50 Inlet channel 51 Inlet temperature sensor 60 Controller 70 Mixed water valve

Front page continuation (72) Inventor Yasushi Yamazaki, 32, Akashi-cho, Chuo-ku, Kobe-shi, Hyogo Prefecture Stock company, Noritsu (72) Inventor, Tsukuhisa Mizuta, 32, Akashi-cho, Chuo-ku, Kobe city, Hyogo Prefecture, Ltd. (72) ) Inventor Naoki Yamamoto 32, Akashi-cho, Chuo-ku, Kobe City, Hyogo Prefecture Incorporated Noritsu (72) Inventor Kiyoshi Takahashi 32, Akashi-cho, Chuo-ku, Kobe City, Hyogo Prefecture Incorporated Noritsu (72) Inventor, Kazuo Sunagawa Hyogo 32, Akashi-cho, Chuo-ku, Kobe, Japan (72) Inventor Shinya Fujimoto, No. 32, Akashi-cho, Chuo-ku, Kobe-shi, Hyogo (72) Inventor, Yoji Hatake Akashi, Chuo-ku, Kobe-shi, Hyogo Town No. 32, Noritsu Co., Ltd. (72) Inventor Takahiro Onishi No. 32, Akashi-cho, Chuo-ku, Kobe, Hyogo Prefecture No. 56, Noritsu Co., Ltd. (56) Reference JP-A-2-68449 (JP, A) JP-A-4 -52455 (JP, A)

Claims (1)

[Claims] 1. A method for heating water from an inlet to an outlet by heating it with an instantaneous heat exchanger, and connecting a bypass from the inlet to the outlet so that water can be mixed with a water mixing valve. and which, set the hot water supply temperature T _MS is set, calculates the necessary heat quantity Q _KO of the instant heat exchanger and a heat exchanger set hot water temperature T _KS and the incoming water temperature T _C and the heat exchanger water inlet flow rate R _KO , The on-time and off-time of the corresponding fuel supply electromagnetic pump are calculated from the calculated heat exchanger required heat quantity Q _KO to start the feedforward supply of petroleum fuel, and at least the on-off cycle of the fuel supply electromagnetic pump In a short cycle,
Current heat exchanger outlet hot water temperature T _K and current hot water supply temperature T _M
And the current input water temperature T _C , the current water mixing ratio K _BK by the water mixing valve, and the preset hot water supply temperature T _MS , the current heat exchanger outlet hot water temperature T _K, and the current input water temperature T _C. The target water mixing ratio K _BKS by the water mixing valve necessary to obtain the hot water supply temperature T _MS is calculated, and the mixing amount is equal to the difference between the target water mixing ratio K _BKS and the current water mixing ratio K _BK. A method for controlling an oil water heater, characterized in that a water valve is feedback-adjusted.