JPH0240444Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a water heater.

As shown in FIGS. 1 and 2, a conventional hot water supply system uses a bridge circuit c that incorporates a hot water temperature sensor a for detecting the hot water temperature and a variable resistor b for setting the hot water temperature. A signal corresponding to the deviation from the set temperature is operationally amplified by an operational amplifier d, and the opening degree of a proportional control valve h interposed in a fuel supply path g of a burner f that heats a heat exchanger e by the output of the amplifier d. The combustion amount of the burner f can be controlled proportionally by adjusting the temperature of the burner f, and the hot water temperature can be controlled to an arbitrary set temperature, or as shown in Figures 3 and 4, there is a A signal corresponding to the deviation between the water supply temperature and the set temperature detected by a bridge circuit m incorporating a water temperature sensor k and a variable resistor l for setting hot water temperature, and a signal corresponding to the water supply amount detected by a water flow sensor n. The operational amplifier o
A signal corresponding to the hot water supply load is output by multiplying by A device is known in which the amount of combustion of water is proportionally controlled and the temperature of hot water discharged can be controlled to an arbitrary set temperature (for details, see Japanese Patent Application Laid-Open No. 75157/1983). Note that j in FIG. 2 indicates the excitation coil of the proportional control valve h, and u in FIG. 4 indicates the excitation coil of the proportional control valve s. However, in these systems, when the hot water supply load exceeds the hot water supply capacity, it is often impossible to raise the outlet temperature to the set value even if the burner is in the maximum combustion state.

The purpose of this invention is to provide a device that can control the hot water outlet temperature to a set temperature even in the above case, and the combustion amount of the burner 2 that heats the heat exchanger 1 is determined by It is equipped with a combustion controller 3 that performs proportional control according to the temperature, and also includes a water temperature sensor 4 that detects the temperature of the water supply, a water flow sensor 5 that detects the amount of water flow, and a temperature of the water flow detected by the water flow sensor 4 and a set temperature. A hot water supply load detector 6 generates an output according to the hot water supply load obtained by multiplying the deviation of the water supply amount by the water supply amount detected by the water flow rate sensor 5, and the hot water supply load detected by the hot water supply load detector 6 exceeds the hot water supply capacity. In some cases, the heat exchanger 1 is characterized by being equipped with a water supply amount controller 7 that reduces the amount of water supplied to the heat exchanger 1 according to the deviation.

FIG. 5 and FIG. 6 show examples thereof,
As the combustion controller 3, a bridge circuit 10 incorporating a hot water temperature sensor 8 for detecting the hot water temperature and a variable resistor 9 for setting the hot water temperature detects the difference between the hot water tap temperature and the set temperature in the form of voltage, The voltage is operationally amplified by an operational amplifier 11, converted into a current form, and inputted to the base of a transistor 12, and a current corresponding to the difference between the hot water temperature and the set temperature is applied to the transistor 12.
A combustion controller 3 similar to that of the conventional device shown in FIG. The current flowing to the collector side is connected to the fuel supply path 1 to the burner 2.
The opening of the control valve 14 and the combustion amount of the burner 2 are proportionally controlled by flowing the current through the excitation coil 14a of the electromagnetic proportional control valve 14 with a valve 3 interposed therebetween.

As the water temperature sensor 4, a thermistor was used, and as the water amount sensor 5, a pressure sensitive diode was used.

The hot water supply load detector 6 has approximately the same configuration as the combustion controller 3 of the conventional device shown in FIG. A bridge circuit 16 includes a variable resistor 15 for temperature setting and outputs a signal corresponding to the deviation between the water supply temperature and the set temperature.
, a water amount sensor 5 that outputs a signal corresponding to the water supply amount, and an operational amplifier 17 that multiplies both signals and outputs a signal corresponding to the hot water supply load.

The water supply amount controller 7 receives an output signal corresponding to the hot water supply load generated from the operational amplifier 17, which is a component of the hot water supply load detector 6, as an input signal, and uses a signal corresponding to the hot water supply capacity as a setting input signal to determine the hot water supply load. an operational amplifier 18 that outputs a signal according to the difference between the two input signals only when the water exceeds the hot water supply capacity; Normally open type solenoid valve 19
A transistor 20 is connected in series to an excitation coil 19a.

Next, to explain its operation, when the outlet hot water temperature is lower than the set temperature, the operational amplifier 11 of the combustion controller 3 normally outputs a voltage according to the difference between the set temperature and the outlet temperature, and the proportional control valve 14 is activated. The opening degree is increased, the combustion amount of burner 2 becomes larger, and the hot water temperature rises. As a result, the hot water temperature is controlled to the set temperature, but if the hot water supply load exceeds the hot water supply capacity, in the conventional device, burner 2 reaches its maximum Despite being in a combustion state, the outlet temperature may not rise to the set temperature. In this case, according to the present invention, an output signal exceeding the hot water supply capacity is obtained from the hot water supply load detector 6, and therefore, the water supply amount controller 7 detects the deviation between the output signal and the signal corresponding to the hot water supply capacity. A corresponding output signal is obtained, the current flowing through the excitation coil 19a increases, the fully open solenoid valve 19 is throttled, the amount of water supplied decreases, and the hot water temperature reaches the set temperature.

Thereafter, when the hot water supply load becomes less than the hot water supply capacity, no output is generated from the water supply amount controller 7, and the solenoid valve 19 returns to its normal fully open state.

As described above, according to the present invention, when the hot water supply load exceeds the hot water supply capacity and the hot water supply temperature does not rise to the set temperature at high load, the water supply amount controller 7 controls the heat exchanger 1
Since the amount of water supplied to the hot water is reduced, the hot water outlet temperature can be maintained at the set temperature when the water supply temperature is extremely low, and the combustion amount of burner 2 is proportional to the deviation between the hot water outlet temperature and the set temperature. Since it is controlled by the combustion controller 3, in the unlikely event that there is an error in the hot water supply load detected by the hot water supply load detector 6,
If the hot water temperature deviates from the set temperature, the hot water temperature sensor 8 detects this and the combustion amount of the burner 2 can be controlled by the combustion controller 3, which has the effect of correcting the error.

[Brief explanation of the drawing]

Fig. 1 is a schematic explanatory diagram of the conventional device, Fig. 2 is its electric circuit diagram, Fig. 3 is a schematic explanatory diagram of another conventional device, Fig. 4 is its electric circuit diagram, and Fig. 5 is the inventive device. A schematic explanatory diagram showing one example, and FIG. 6 is an electric circuit diagram thereof. 1... Heat exchanger, 2... Burner, 3... Combustion controller, 4... Water temperature sensor, 5... Water amount sensor, 6... Hot water supply load detector, 7... Water supply amount controller.

Claims (1)

[Scope of utility model registration request] It is equipped with a combustion controller 3 that proportionally controls the combustion amount of a burner 2 that heats a heat exchanger 1 according to the deviation between the hot water temperature and the set temperature, and a water temperature sensor 4 that detects the water supply temperature, and a water supply amount. a water flow sensor 5 that detects the temperature, and a hot water supply load detection system that generates an output according to the hot water supply load obtained by multiplying the deviation between the water supply temperature detected by the water temperature sensor 4 and the set temperature by the water supply amount detected by the water flow sensor 5. 6, and a water supply amount controller 7 that reduces the amount of water supplied to the heat exchanger 1 according to the deviation when the hot water supply load detected by the hot water supply load detector 6 exceeds the hot water supply capacity. A water heater characterized by: