JPS58219351A - Water heater control device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control device that automatically adjusts the amount of hot water supplied in a water heater that uses gas, oil, electricity, etc. as a heat source to provide hot water at a set temperature at any time.

Here, we will explain water temperature control in a water heater that uses gas as fuel as an example.

2/, l Figure 1 shows the configuration of a conventional gas water heater. In the figure, 1 is a gas burner serving as a heat source, and 2 is a heat exchanger that replaces the combustion heat of the gas burner 1 with water to supply hot water.

3 is a temperature controller, which receives a signal (TW
O) and the signal (TWR) from the temperature setting device 5 are input, a predetermined combustion amount is determined from the deviation of the signal (TER = TWR - TWO), and the supply heat amount controller 6 is controlled to set the hot water temperature (
TWO) is controlled. In general, the hot water temperature detector 4 uses a mister or thermocouple, and the algorithm for controlling the hot water temperature uses a proportional integral differential method (PID).
(method) and other combinations of control laws are often used.

Figure 2 is a characteristic diagram of the hot water supply capacity of a gas water heater, showing the hot water supply amount (Fw) and temperature rise value (Δ
T). Said Qqrnax.

FW and ΔT are η・oq, where η is the heat exchange efficiency
-71111w ・・・・・・・・・(1)aX and further ΔT−η・Qqmax/Fw ・・・・・・・・・
・(2) 3 Page 2・ It is written as follows. In other words, each hot water supply amount (Fw)
There is no temperature rise above the capacity characteristic shown in FIG. For example, the amount of hot water supplied during major combustion is (FWl)
As shown in the figure, the temperature rise value is (ΔT
1). The above-mentioned temperature controller 3 adjusts the amount of hot water Fw to Fw when the difference between the signal from the temperature setting device 5 and the incoming water temperature (TWi), the value TUP to which the temperature should be raised, is ΔT1.
It acts effectively in the region l. However, Fw>Fwl
In the hot water supply range, that is, in the overload range, it becomes impossible to control the hot water temperature, and the hot water temperature will never reach the set temperature no matter how long it takes.

In this way, the maximum combustion amount Qqmax limits the amount of hot water that can be supplied, the hot water temperature of which can be controlled.

The present invention eliminates the above-mentioned conventional drawbacks, absorbs fluctuations due to changes in the inlet pressure of water that is a load, and variations in the supply water flow rate controller that is a component of the equipment, and ensures that hot water is always at the desired temperature. The purpose is to provide a control device that can be obtained.

In order to achieve the above object, in the present invention, the difference (TUP) between the signal from the temperature setting device (TWR) and the signal from the incoming water temperature detector (TWi) is determined by the hot water supply capacity shown in FIG. Based on the characteristics, a water flow control signal is output so that a predetermined hot water supply flow rate (FW) of ΔT-TUP is achieved.

Alternatively, the deviation (TER) between the signal (TER) of the temperature setting section and the signal (TWO) of the hot water temperature detector is a predetermined value (T
a water flow controller that outputs a water flow control signal to reduce the hot water flow (Fw) by a predetermined value when the water flow rate (Fw) is equal to or higher than ERl); and a water supply flow controller that controls the flow of water supplied to the water heater in response to the output of the water flow controller. , an operating position detector that operates in conjunction with the water supply amount controller, and an output signal (P) of the operating position detector.
is fed back to the water amount controller, and the amount of water supplied is controlled while checking the operating state of the water amount controller.

The water heater control device of the present invention will be explained along with its operation.

When setting the supply water amount that can control the temperature depending on the hot water supply capacity characteristics shown in Figure 2 from the difference between the set temperature and the incoming water temperature, that is, the temperature rise value (TUP), When the temperature deviation is greater than a predetermined value and the water supply amount is set to a predetermined amount, a signal is output from the water flow controller to the water supply flow controller to operate the throttle or opening in a newly set direction to achieve the predetermined water flow. While checking the set water flow rate control position with a position detector linked to the water supply flow rate controller, operate the water supply flow rate controller, and stop it when the output signal of the predetermined position detector is obtained, and then adjust the water flow to the specified water flow rate. to control.

Generally, as a position detector, a potential meter, a disk with a hole connected to a water supply amount controller, a photocoupler that detects the hole, or the like is used.

Here, an example in which a photocoupler is used as a position detector will be explained.

In FIG. 3, an embodiment of the control method using the position detector of the present invention will be described, taking as an example water flow control with a difference between TUP setting and water inflow. The same numbers as in FIG. 1 indicate components having similar functions. Signal of temperature setting device 6 (
TWR) and the signal (TWi) from the inlet water temperature detector 7 are input to the water flow rate controller 8, and a control signal is output to the water supply flow rate controller 9 so that the amount of water supplied is equal to the amount of water supplied based on the hot water supply capacity characteristics shown in Fig. 2. do. The position detector 10 operates in conjunction with the operation of the water supply amount controller 9, and feeds back an output signal to the water amount controller 8. The water flow controller 8 performs a one-shot determination of the predetermined water flow and the signal from the position detector 10, and controls the water flow controller 9 while confirming its position, thereby controlling the flow of water to the water heater. Note that the water amount control section refers to the water amount controller 8, the supply water amount controller 9, and the 1 degree position detector.

FIG. 4 shows a part of the water supply amount control section 9 and a specific example of the position detector 10 of the present invention. Reference numeral 11 in parentheses indicates a water flow valve installed in the water pipe 12 of the water heater, which controls the amount of water supplied in conjunction with the rotation of the output shaft 14 of the geared motor 13. A photocoupler 15 is used as a position detector for the water flow valve 11, and detects the hole in the holed disk 16 which is linked to the rotational movement of the output shaft 14 to determine the position. The position detection method using a photocoupler is shown in Fig. 4 (Fig. 4). The same numbers as those in FIG. 3(a) indicate the same components. 16
As mentioned above, is a disk with a hole, and the hole in the disk soil is provided with seven peno-coded holes representing the amount of water, and rotates about the output shaft 14 in the direction of the arrow in the figure. Assuming that the rotation of the full arrow in the training direction is the opening direction of the water flow valve 11, if the rotation in the opening direction is continued, the photocoupler 15 will eventually detect the code hole 17 indicating the maximum open position and stop the geared motor 13. At this time, the water flow valve 11 is in the open state, that is, the maximum amount of water is being supplied to the water heater.Thereafter, by rotating counterclockwise, the water flow valve 11 is gradually throttled to limit the water supply amount.

When reducing the predetermined amount of water, the photocoupler 15 detects the number of disk holes or the code hole indicating the predetermined water amount from the maximum water amount position 17.

Next, FIG. 5 shows the time characteristics of (a) outlet hot water temperature - set temperature, (d) supply water amount, (C) output signal of the position detector, and (d) drive signal to the supply water amount controller. In this example, when the power is applied (1=1), TUP (TUP - Δ
T2) to determine the amount of water (Fw-2w2) to be set, output a drive signal (open signal) to the supply water amount control position in order to set the position (P-P2) indicating the amount of water (2w2), and set the position signal P.
The drive signal is stopped at the time when 2 is detected (1=11). Next, combustion starts at 1 = 12 and the hot water temperature (T
WO) is -1: rises and approaches the set temperature. Next, at t-13, the set temperature was changed, so the difference from the inlet water temperature (TUP-
ΔT1) is changed, and the predetermined water amount is changed to (Fw=Fw1). Similarly to the above, a signal to throttle the water flow valve to the water flow position (P=P1) is output to the supply water flow controller, and a position signal P1 is output to the water supply flow controller.
The drive signal is stopped at the time when (1=14) is detected.

FIG. 6 shows the correspondence between the hot water supply capacity characteristics shown in FIG. 2 and the position detector explained in FIG. 4. The position code is set so as not to exceed the maximum combustion.

As explained above, according to the water heater control device of the present invention, the amount of water supplied is always regulated within a range where the hot water temperature can be controlled, so hot water at the desired temperature is always obtained. Furthermore, since the amount of water to be supplied is controlled while checking the position of the water supply amount controller, it is possible to eliminate mechanical variations in the water amount controller and realize reliable water amount control.

[BRIEF DESCRIPTION OF THE DRAWINGS] Page 9 Figure 1 is a configuration diagram of a water heater showing a conventional example, Figure 2 is a hot water supply capacity characteristic diagram of the water heater, and Figure 3 is a configuration diagram of a water heater of the present invention.
Figures 4(d) and (1)) are diagrams showing an embodiment of the position detector which is a part of the water flow control section of the present invention, and Figure 6 is a diagram showing (-) hot water temperature/set temperature/(b). Fig. 6 is a diagram showing the time characteristics of the water supply amount, (C) the output signal of the position detector, and (d) the output of the water flow controller. 3... Temperature controller, 4... Hot water temperature detector, 5... Temperature setting device, 6... Supply heat amount controller, 3, 4, 6 - Temperature control section at 6, 7... Water inlet temperature detector, 8... Water flow rate control section, 9... Supply water flow rate controller, 10...
・Water flow control unit with position detector, 7/8/9/1o. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 Figure 6 Figure 4 Figure 5

Claims (1)

[Claims] A temperature control unit that controls the amount of heat supplied to the water heater in response to the difference (TER) between the set temperature and the hot water outlet temperature, and a predetermined water amount based on the difference (TUP) between the set temperature and the incoming water temperature or the deviation (TER). (FW) and controls the amount of water supplied to the water heater. A control device for a water heater that controls a water flow control unit by making a tentative judgment with respect to an output signal (P) of a detector.