JPS6111550A - Remaining hot-water indicating circuit for hot-water supplier - Google Patents

Abstract

PURPOSE:To avoid omission of indication of remaining hot-water and indicate correct amount of remaining water by a method wherein an indicating element, corresponding to a sensor provided at the lower part of the hot-water supplier, is lighted when the sensor has detected a predetermined temperature regardless of the existence of a signal from another sensor provided at the upper part of the hot-water supplier. CONSTITUTION:A hot-water reserving tank 1 is provided with a thermistor 2a at the upper part thereof, the thermistor 2c at the lower part thereof and the thermistor 2b at the middle part thereof. When a comparator 9, connected to the middle thermistor 2b, does not detect the signal of remaining hot-water detection due to the variability or the like of the thermistor or circuit element in spite of the existence of sufficient remaining hot-water in the lower part of the hot- water reserving tank 1, the comparator 8, connected to the lower thermistor 2c, outputs the signal of remaining hot-water detection and a LED14 is lighted by a LED driver 11. The LED15 is connected to the LED11 through a diode 19, therefore, the LED15 is lighted by the LED driver 11 even when the LED driver 12 does not operate and the indication under the omitted condition may be avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a control circuit for a water heater, and particularly to a control circuit for continuously displaying the amount of hot water remaining in the water heater.

Conventional configuration and its problems In the conventional water heater control circuit, the remaining hot water amount is 21\-
2. In the case of full display, a bar graph display using an LED using a plurality of thermistors as sensors is common.

However, due to variations in the thermistor, there is a risk that the bar graph will not be displayed continuously but will be displayed in a so-called "missing" manner, where the graph is missing in the middle, giving the user a sense of anxiety that the display may be malfunctioning. Met.

FIG. 1 shows the configuration of the remaining hot water display in a conventional water heater.

1 is a hot water storage tank, 2a to 2c are thermistors for detecting the amount of remaining hot water, 3 is a hot water inlet, 4 is a water inlet, 6 is a control circuit that transmits a display signal to the remaining hot water indicator 7, and 6 is a transmission cable.

FIG. 2 shows the configuration of the remaining hot water display circuit of a conventional water heater. The operation will be briefly explained below.

Consider a case where the temperature of the hot water inside the hot water storage tank 1 stabilizes at a temperature slightly higher than the temperature detected by the thermistors 2a to 2C. If there is enough hot water inside the can, the thermistor 2
Comparators 8 to 1o connected to each other output a signal for detecting remaining hot water based on the signals from a to 2c. This remaining hot water detection signal is given to the LED drivers 11-13, and the remaining hot water display LEDs 14-17 are turned on. The LED 17 is always lit. However, although there is no problem if the thermistors 2a to 2C all operate at the same temperature, disadvantageous phenomena may occur due to variations in the characteristics of the thermistors. For example, even though there is sufficient hot water inside hot water tank 1,
If the comparator 9 does not output a signal for detecting remaining hot water due to variations in the characteristics of the thermistor 2b, the LED 14
, 16 and 17 are lit, and the LED 16 is turned off, which is a so-called "out of the blue" state. Fig. 3a shows a normal state, and b shows an unusual abnormal display (hatching indicates a lighting state). When the out-of-water display is displayed, there are problems in that the amount of remaining hot water cannot be accurately displayed and the user feels uneasy about whether the equipment is malfunctioning.

OBJECTS OF THE INVENTION The present invention addresses the above-mentioned conventional problems and eliminates the display of remaining hot water in a water heater, thereby eliminating the user's sense of anxiety and providing a more accurate display of remaining hot water.

Structure of the Invention In order to achieve all of the above objects, the basic structure of the present invention consists of an upper hot water supply port, a lower water supply port, and a plurality of water supply ports provided at each fixed tank capacity from the hot water supply port to detect the water temperature. When the sensor detects all the hot water above a certain temperature, the display element of the remaining water indicator corresponding to that sensor lights up, and the sensor installed at the bottom lights up the display element of the remaining water indicator when the sensor detects all the hot water above a certain temperature. When this happens, the display element corresponding to this sensor is turned on, regardless of the presence or absence of a signal from the sensor provided above.

Description of examples FIG. 4 shows a circuit diagram of this embodiment.

Thermistors 28 to 2C are used as sensors for detecting the amount of remaining hot water, and the thermistor 2a is provided at the upper part of the hot water storage tank 1, the thermistor 2C is provided at the lower part of the hot water storage tank, and the thermistor 2b is provided in between. The water temperature inside hot water tank 1 is
Consider a case where the temperature is stabilized slightly higher than the temperature detected by the thermistors 2a to 2b. If there is a sufficient amount of hot water inside the hot water storage tank 1, the thermistors 2a to 2cf)
> The comparators 8 to 10 connected to each output a signal for detecting remaining hot water. This remaining hot water detection signal is given to the LED drivers 11-13, and the remaining hot water display LEDs 14-1 are turned on.

The LED 17 is always lit. The above is normal operation. However, even though there is enough hot water to reach the bottom of the hot water storage tank 1, due to variations in thermistors and circuit elements, the comparator 9 connected to the thermistor 2b in the center of the hot water storage tank 1 does not detect a residual hot water detection signal. Considering this, the LED driver 12 cannot drive LED1sfr. Conventionally, the protrusion shown in FIG. 3 would indicate the status. In this embodiment, there is enough hot water in the reeds at the bottom of the can body, so the thermistor 2 c at the bottom of the hot water storage tank 1
The comparator 8 connected to K outputs a signal for detecting remaining hot water, and the LED driver 11 lights up the LED 14. LI! : Diode 19 in D driver 11
ff: Since the LED 15 is connected through the
1, the LED 16 is turned on and the status of the exit is no longer displayed. The above is the basic move to reduce the situation to Defense 1. Similarly, the LED driver 12 includes a diode 20 for simultaneously lighting 16 LEDs that are turned on by a signal from a comparator 10 connected to a thermistor 2a at the top of the hot water storage tank 1.

In addition, in FIG. 4, 18 is a power supply circuit block, 21 to 2
6 is a reference resistor that determines the temperature for detecting remaining hot water, 26 to 28 are pull amplifier resistors for comparator output, and 29 to 32 are LEDs.
The current limiting resistors 33 to 36 each represent a feedback resistor.

According to the present invention, as described in ``Effects of the Invention'', if the remaining hot water indicator is missing midway, it will no longer be displayed and give the user a sense of anxiety that the indicator may be malfunctioning. This has the effect that users can use it with peace of mind.

[Brief explanation of drawings]

7 Heh. Fig. 1 is a block diagram of the water heater and the remaining hot water indicator, Fig. 2 is a block diagram of the conventional remaining hot water display circuit, and Fig. 3 is the state of the remaining hot water display.
Fig. 4 shows a normal state, b shows a toothless state, and Fig. 4 is a configuration diagram of an embodiment of the present invention. 1...Hot water storage tank, 2a to 2C...Sensor, 3...Hot water supply [1, 4...Water inlet,
7... Remaining hot water indicator.

Claims (1)

[Claims] It is equipped with an upper hot water supply inlet, a lower water supply inlet, and a plurality of sensors installed at each fixed tank capacity from the hot water supply inlet to detect the water temperature, and when the sensor detects a temperature above a certain level, the sensor In addition to lighting up the display element of the corresponding remaining water indicator, when the sensor installed at the bottom detects a temperature above a certain level, regardless of the presence or absence of a signal from the sensor installed at the top, the upper A water heater's remaining water display circuit that also lights up the display element corresponding to the sensor.