JPS5866749A - Controller of hot water supplier - 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 hot water temperature control for water heaters that use gas, oil, electricity, etc. as a heat source, and solves the conventional problem of not being able to obtain hot water at a set temperature when the water supply is overloaded with a large amount of water. In order to solve the problem, the present invention aims to provide a new control device that provides a water supply amount controller, stabilizes the amount controlled by the water supply amount controller, and quickly supplies hot water at a desired set temperature.

Hereinafter, a gas water heater that uses gas as fuel will be described as an example.

FIG. 6 is a block diagram of a conventional gas water heater, in which combustion heat from a gas burner 1 serving as a heat source and water are exchanged with a heat exchanger 2 to provide hot water. - The temperature controller 3 takes in the signal (TWO) from the hot water temperature detector 4 and sets the temperature i (TWR), !
A predetermined combustion amount is determined from the :O deviation (TER=TWR-TWO), and the supply heat amount controller 5 is controlled to control the hot water temperature. Generally, a thermistor is often used as the hot water temperature detector 4, and a PID method is often used as the hot water temperature control algorithm.

Figure 7 shows the water supply amount (Fw, ) and temperature rise (
7), the solid line is the maximum amount of heat supplied (Qqm
aX). The maximum amount of heat supplied and temperature rise is the amount of water supplied, where η is the combustion efficiency, η” gmax =
FW''' (1), which is further written as T-η''gmax/FW (2). Therefore, at a certain amount of water supply, the temperature does not rise above the level indicated by the solid line in the figure. For example, Fw
When the water supply amount is -Fwl, the temperature rise becomes T=T as shown in the figure.

When the difference (TUP=TWR-TWI) between the set temperature (TWR) and the inlet water temperature (TWI) is T1, the three temperature controllers described above operate effectively in the range of water supply amount Fw to Fwl. However, when the amount of water supplied is greater than Fwl, that is, when the load is large, control becomes impossible, and the hot water temperature TWO barely reaches the set temperature TWR even after a single operation.

In this way, the maximum combustion amount QC1ma X limits the amount of water Fw that can be used to control the hot water temperature.

It is an object of the present invention to provide a control device that eliminates such drawbacks of conventional water heaters, allows a desired hot water temperature to be obtained at all times, and reaches a set temperature within a short period of time after the start of use.

FIG. 1 is a configuration diagram of a gas water heater of the present invention.

Devices with the same numbers as in FIG. 6 are devices having the same functions. The control device 6 receives the signal TWO from the hot water temperature detector 4.
The amount of heat supplied is controlled in the same way as described above based on the deviation from the set temperature, and even if the set temperature has not been reached even after a predetermined period of time has passed, taking into consideration process delays and controllability, after starting hot water temperature control, and when maximum combustion occurs, It outputs a drive signal to control the water flow controller No. 7. The drive signal is transmitted to the water amount controller via the water supply amount control position detector 8. Regarding this hot water temperature controllability and drive signal transmission configuration, the second
This will be explained with reference to the figure and FIG.

In FIG. 2, A is the time characteristic of the water supply amount, and B is the time characteristic of the outlet temperature. When 1=10, at the start of use, the water flow controller 7 is fully opened to maximize the water supply capacity. The period between 101 and 101 is up to td, and the hatched portion in Figure A shows the operation from the predetermined amount of water supply to the maximum. tl is one point in time after the elapse of a predetermined period of time in consideration of the above-mentioned controllability.At this point, the hot water temperature TWO has not reached the set temperature, so the water supply amount is reduced by a predetermined amount to obtain the set temperature. A predetermined time is required to maximize the water supply capacity, and from the viewpoint of hot water temperature control, it is desirable that the driving time be short. Therefore, the maximum flow rate position is detected, the detection signal is fed back to the drive unit, and the generation of the drive electric signal is stopped.Since the flow rate change has stopped, the above-mentioned predetermined time counting can be started in consideration of controllability. Temperature control operation can then be started.

FIG. 3 is a circuit diagram showing how the water supply amount control position detector 8 intervenes in transmitting a drive signal to the water amount controller 7. 9r1 [, is a controller that controls the drive signal,
An example is shown in which a DC motor 1o is used as a drive source in a water flow controller. Transistors 11, 12 as switch operation
, 13.14 is due to the on/off combination of so, h, etc.
The rotation direction of the motor 1° is determined, and the water flow controller is operated in the opening direction or the closing direction. In this figure, transistors 11 and 14 are on, transistors 12.13 are turned on in the opening direction to increase the water supply amount when they are off, transistors 12.13 are on,
11 and 14 are set to rotate in the closing direction when turned off. As is clear from the figure, the position detector 8 is interposed as a contact in the opening force direction signal transmission path, and if it is composed of, for example, a microswitch, it will be in a non-conducting state when fully opened, and if it is in the opening direction drive state. Even if the signal 9 is output from the controller 9, the motor 1o does not rotate. While the fully open position detection signal kTI1 and the open direction signal are being generated, a LOW level signal is input to the controller 9 when the position detector 8 is conductive, and a HIGH level signal is input to the controller 9 when the position detector 8 is not conductive.

After determining the fully open position by determining this signal, transistors 11 and 14 are turned off to stop unnecessary driving.

FIG. 4 is a configuration diagram of a gas water heater when an inlet water temperature detector 16 is installed. The signal TWI from the detector 15 is input to the temperature controller 16, and the water supply amount is determined in advance from the difference TUP from the set temperature. The water flow controller 7 is driven to limit the amount of water. This is possible if the relationship shown in FIG. 7 and the water supply amount control characteristics of the water amount controller are known, and the set temperature can be reached in a shorter time than the hot water temperature control shown in FIG. 2.

This situation is shown in FIG. A represents the time characteristic of the water supply amount, and B represents the time characteristic of the hot water outlet temperature. In tdl, there is a full open operation period as described above, and then Fw is activated according to 7TUP.
The amount of water is controlled so that the set water temperature is obtained. Furthermore, when the desired water temperature is not reached due to variations in the water flow controller, fluctuations in water pressure, etc., there is also a method of obtaining the set temperature by further adjusting the water reserve 2w3 from the deviation TER as in FIG. 2. In the configuration example shown in FIG. 4, the incoming water temperature sensor 16 is separately provided, but the outgoing water temperature sensor 4
There is also a method of using the detected temperature as TWI.

As explained above, according to the water heater control device of the present invention, since the water supply amount is controlled according to the capacity characteristics of the water heater, the desired hot water temperature can always be obtained, which is a great advantage, and the maximum flow rate control position can be detected. Through the operation of the position detector, drive signal transmission is directly controlled, eliminating system delays and unnecessary control operations, and a position detector with a simple configuration can generate a shadow detection signal at a predetermined position, improving hot water temperature control. can also be improved.

[Brief explanation of the drawing]

Figure 1 is a configuration diagram of the gas water heater of the present invention, Figure 2A,
B is a water supply flow rate control diagram and a hot water temperature characteristic diagram by the control device of the present invention, FIG. 3 is a configuration diagram showing one implementation of the water flow controller drive unit of the present invention, and FIG. 4 is a diagram showing another implementation of the present invention. Configuration diagram of an example gas water heater, No. 51\IA. B is a water supply amount control diagram and a hot water temperature characteristic diagram according to the embodiment shown in FIG. 4, and FIG.
The figure shows the capacity characteristics of a water heater. 4I... Output hot water temperature detector, 6... Supply heat quantity control fill device, 6... Temperature controller, 7...
...Water supply amount controller, 8...Water supply amount control position detector. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2, Figure 3, y. Figure 4 Figure 5 Figure 6! , gJ Figure 7 FW Peng t

Claims (1)

[Claims] a hot water temperature detector; a temperature controller that controls the amount of heat supplied to the heat source depending on the deviation between the signal of the detector and the set temperature; and a controller that controls the amount of heat supplied in response to the output of the temperature controller;
and a water supply amount controller to which a driving electric signal is transmitted via a water supply amount control position detector, and the position detector simultaneously interrupts the electric signal for driving the water amount controller by detecting a predetermined water supply amount control. A water heater control device that generates a predetermined water supply amount detection signal.