JPH01150745A - Water amount control device for hot water feeder - Google Patents

Abstract

PURPOSE:To enable check of a water amount control valve for failure in operation and to enable prevention of the occurrence of seizure of a drive motor, by a method wherein the water amount control valve is controlled to a maximum opening position during non-combustion before operation of a hot water feeder, and a time is limited to control of the maximum opening position to suppress energization to a water amount control valve drive motor. CONSTITUTION:ON and OFF of combustion of a burner 2 is controlled upon whether an amount of water flowing in a heat exchanger 1 exceeds an ignition combustion water amount. When a hot water feed faucet 3 is closed to stop operation of a heat water feeder, in a step P10, the present position of a water amount control valve 10 is confirmed. If it is not a maximum opening position, a timer is set in a step P11, and a valve opening signal is outputted in a step P12. When a maximum opening detecting switch 12 is turned ON within a period of a timer, energization to a motor 11 is stopped in a step P13 to confirm the normal motion of the water amount control valve. When a maximum opening is not detected within the period of the timer, abnormality on a water amount control valve 10 is set in a step P14, and in the following, energization of a water amount control valve drive motor 11 is prohibited in a step P15.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a water flow control device for controlling the flow of hot water from a gas instantaneous water heater or the like.

BACKGROUND OF THE INVENTION Conventional control devices of this type include a fuel control valve (for example, a gas proportional control valve) that adjusts the amount of combustion so that the hot water temperature reaches a set temperature.

In addition, if a heat load that exceeds the maximum capacity of the water heater is requested, the hot water temperature will drop, so to prevent this, the water supply amount will be automatically reduced if there is a heat load request that exceeds the maximum capacity. A control valve is provided. These water flow control valves are generally driven by a DC motor, and the opening degree of the water flow control valve is adjusted by a water flow rate sensor, a timer, etc. Publication No. 62-40624, Utility Model Publication No. 62-12015
Publication No. 4).

Problems to be Solved by the Invention However, with the above configuration, if the operation of the water flow control valve is not confirmed before operation of the water heater or the opening degree is unknown, and the water flow control valve becomes inoperable due to foreign matter entangled with it, the driving There was a problem that the motor could burn out.

The present invention solves these conventional problems.

The purpose is to check the operation of the water flow control valve before operating the water heater.

Means for Solving the Problems In order to solve the above problems, the water flow control device of the present invention includes:
The water flow control valve is configured to control the water flow control valve to the maximum opening position before operation of the water heater, that is, during non-combustion, and to set a time limit on the maximum opening position control to suppress energization to the water flow control valve drive motor. It is.

Function: With the above-described structure, the present invention can check for failure of the water flow control valve and prevent burnout of the drive motor.

Embodiments Hereinafter, embodiments of the present invention will be described based on the accompanying drawings.

FIG. 1 is a control system diagram of a water heater that is an embodiment of the present invention, in which 1 is a heat exchanger, and 2 is a burner that heats the heat exchanger 1. Hot water is heated through a hot water supply cylinder 3. Ru. 4 is a hot water temperature detector that detects the temperature of the hot water heated by the heat exchanger 1; 6 is a fuel regulator that adjusts the amount of gas supplied to the bath 2; 6 is a temperature setting device; and 7 is a combustion amount control means. Then, the temperature detected by the hot water temperature detector 4 is fed back to control the fuel regulator 6 so that the temperature is set by the temperature setting device 6. The combustion amount control means 7 is a general proportional one.

It consists of PID feedback control of integral and differential control. 8 is an inlet water temperature detector that detects the temperature of water supplied to the heat exchanger 1; 9 is a water quantity detector that detects the amount of water supplied; 10 is a water quantity control valve that controls the amount of water supplied; the valve opening direction is controlled by the drive motor 11; and drive in the aperture direction. 12 is water flow control valve 1
Maximum opening detection switch that turns on at the maximum opening position of o, 1
Reference numeral 3 denotes water flow control means for controlling the water flow control valve 10, which executes the control contents shown in FIG. FIG. 2 shows an operation flowchart when the system is configured with a microcomputer or the like.

In FIG. 2, in step P, the capacity water amount FL is calculated from the set temperature Ts set by the temperature setting device 6, the inlet water temperature Ti detected by the inlet water temperature detector 8, and the heating capacity QG of the water heater!
11ax is calculated using the following formula.

FLwax ” QCr/TB Ti Step P2
Then, the deviation water amount Δf between the capacity water amount 'LmtLX and the water supply amount ξ detected by the water amount detector 9, which is the amount of water being supplied to the heat exchanger 1, is determined. That is, Δ/L = FL11
At O step P where 1aX 'L, the above △fL
If the value is within the specified range, for example within ±14, the energization of the motor 11 that drives the water flow control valve 10 is stopped in step P4.

If ΔfL is equal to or greater than the above-mentioned regulation, Δft,
The opening/closing direction of the water flow control valve 1o is determined according to the sign of the water flow control valve 1o.

That is, when the sign of △fL is e, FL! ! 12LX
< In the FL state, the water supply amount exceeds the capacity water amount,
A valve close signal is output in step P6 to throttle the water flow control valve 10. Also, when the sign of Δf is ■, FL, n, x<
In the state of FL, the water supply amount ξ is the capacity water amount FLl! la!
It is in a smaller state. This may be due to the user adjusting the hot water supply switch 3. Therefore, in step P7, if the water flow control valve 1o is at its maximum opening and the maximum opening detection switch 12 is on, the power supply to the motor 11 is stopped. Otherwise, a valve opening signal is output in step P8. In both cases, at step P, ΔfL is within the specified range, for example ±1.
If the value falls within e, the water/monetary control will be stopped.

The above control processing is performed when the water heater is performing normal combustion operation, and the judgment is made in step P9. That is, combustion on/off of the burner 2 is controlled depending on whether the amount of water flowing into the heat exchanger 1 is greater than the amount of ignited combustion water. When the user closes the hot water supply valve 3 to stop the operation of the water heater, the current position of the water flow control valve 1o is confirmed using step P1°. At this time, if the water flow control valve 10 is not at the maximum opening position, a timer is set in step P11, and a valve opening signal is output in step P12. If the maximum opening detection switch 12 is turned on within the time set by the timer, the power supply to the motor 11 is stopped at step P+3, and the normal operation of the water flow control valve is confirmed. If the opening cannot be detected, the water flow control valve 1o is opened in step P14.
After that, steps P and 5 prohibit energization of the water flow control valve drive motor 11.

In the above configuration, before the combustion operation of the water heater, the water flow control valve 1o is set to the initial position, which is the maximum opening, by the on/off detection of the maximum opening detection switch 12, and the operation of the motor 11, which drives the water heater to the maximum opening, is controlled. It has the effect of limiting the time, and has the effect of being able to check the operation of the water flow control valve 1o before hot water supply operation.

Effects of the Invention As described above, the water flow rate control device for a water heater of the present invention provides the following effects.

(1) Since the water flow control valve is controlled to the maximum opening position before the combustion operation of the water heater, the initial opening of the water flow control valve is determined and stable water flow control is possible.

(2) It is possible to check the operation of the water flow control valve before the combustion operation of the water heater, and by setting a time limit for the control operation, it is possible to prevent motor overload burnout due to a stuck state of the water flow control valve.

(3) If there is a heat load request that exceeds the maximum capacity of the water heater, the amount of water supplied is reduced to the capacity water amount, so the drop in hot water temperature can be shortened and hot water can be poured at the set temperature.

[Brief explanation of the drawing]

FIG. 1 is a control system diagram of a water flow control device for a water heater according to an embodiment of the present invention, and FIG. 2 is an operation flowchart of the water flow control means. 1...Heat exchanger, 2...Burner, 7.
... Combustion amount control means, 1o ... Water flow control valve, 12 ... Maximum opening degree detection switch, 13 ...
...Water flow control means. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
figure

Claims (1)

[Claims] a heat exchanger, a burner that heats the heat exchanger, a combustion amount control means that detects the outlet temperature of the heat exchanger and adjusts the combustion amount to obtain a set temperature; When there is a heat demand load that exceeds the maximum capacity and the set temperature is not reached by the provided water flow control valve and the combustion amount control means, the water flow control valve is throttled to the capacity water flow, and when no combustion is occurring, the water flow control valve is adjusted to the maximum opening. A water flow control device for a water heater, comprising a water flow control means that controls the position and sets a time limit for maximum opening position control.