JPS6124829Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a temperature setting device for hot water appliances such as water heaters.

(Problems with conventional technology) Increasingly, conventional hot water appliances use semiconductor electronic circuits to set the temperature, as disclosed in Japanese Unexamined Patent Publication No. 189221/1982, but in this case, there are problems. When the power to a device is cut off unintentionally by the user, such as during a power outage or when the outlet is unplugged, the operating mode of many integrated circuit ICs and LSIs is unstable, so the temperature at the time of power return may vary. This means that there is a risk that the settings could become too hot.

(Means for Solving the Problems) The present invention aims to eliminate such dangers, and in order to achieve this purpose, the present invention sets the temperature by emitting an output corresponding to the operation of the temperature setting switch. The IC of the temperature setting circuit that performs
A reset signal is issued to the reset terminal of the IC, so that the output of the IC is reset to the low temperature output side at the time of reset.

(Function) According to the above configuration, when the power to the appliance is restored after being cut off due to a power outage or being unplugged, the reset circuit operates and issues a reset signal to the reset terminal of the IC in the temperature setting circuit.
In this IC, the output is forcibly reset to the low temperature output side by such a reset signal.

(Example) Figure 1 shows its basic configuration. 1 is a temperature control circuit that generates a temperature control output to vary the combustion amount of the burner; in the case of a proportional control device, a temperature setting circuit 2, which will be described later, is used. By changing the value of the reference signal with which the hot water temperature detection value detected by the thermistor is compared with the output of , the combustion amount is increased or decreased by the deviation. Reference numeral 2 denotes a temperature setting circuit which outputs a temperature setting output to the temperature control circuit 1, and its input signal is applied from an input signal line passing through the operation switch 3 through an operating section such as a switch. Reference numeral 4 denotes a reset circuit associated with the temperature setting circuit 2, which controls the temperature setting circuit 2 so that the output of the temperature setting circuit 2 is around a predetermined value each time the main power source before and after the operation switch 3 is applied. This adds a reset output. FIG. 2 shows a specific example of the circuit described above, in which a temperature setting circuit 2 receives an input signal from a signal line 5 via an operation switch 3 via a temperature setting switch 6, and an IC 7 that outputs an output signal from an output terminal. It is composed of: In order to take out this output, the plurality of output terminals 8, 9, 10, and 11 of the IC 7 are sequentially switched to a conductive state from the low temperature setting side terminal 8 to the high temperature side terminal 11 every time the switch 6 is turned on. and output lines 13, 14, 15,
16 are connected. These output lines are used as input signals to an amplifier 17, and the output of this amplifier 17 is applied to the temperature control circuit 1 as a temperature control output. In addition, by applying the operating power to the IC 7 directly from the stage before the operation switch 3, that is, from the power outlet, when reusing the IC 7 after turning off the operation switch 3, it is possible to check the previous output state, that is, from which output terminal the output was output. The device is configured to store the temperature in memory, and as long as the power outlet is plugged in, the temperature setting can be restarted from scratch, eliminating the hassle. Like the IC 7 of the temperature setting circuit 2, the reset circuit 4 operates by applying power from an outlet.To illustrate the circuit configuration, as shown in FIG.
A reset output 22 is connected to the midpoint of the CR timer 20 between the CR timer 20 and the resistor 19 through the inverter 21, and in the case of FIG.
In the case of FIG. 4, the Hi (high) outputs are respectively output as reset signals. This reset output line 22 is connected to the reset terminal 23 of the IC 7 of the temperature setting circuit 2. In addition
A light emitting diode 24 may be connected to each of the output terminals 8, 9, 10, and 11 of the IC 7 to display the output state of the IC 7.

In such a configuration, by turning on the operation switch 3, setting operation with the temperature setting switch 6 becomes possible, and each time the switch 6 is pressed to close the contact, the output terminal of the IC 7 is switched, and the output terminal of the IC 7 is changed accordingly. The temperature control circuit 1 comes to operate based on the output signal value output from the output line. For example, if a power outage occurs while the IC is being used at medium temperature, that is, terminal 9 or terminal 10, and then the power is restored, the IC will be reset if the reset circuit 4 is not installed.
7 may occur, and an output may suddenly be generated at the output terminal 11 on the high temperature side. In contrast, in the above configuration, when the power is restored, the reset circuit 4 operates to forcibly reset the temperature setting circuit 2 so that the output returns to the safe low temperature side, that is, to the output terminal 8 side. This also applies if the power outlet is accidentally unplugged.

(Effects of the invention) Therefore, as described above, according to the present invention, even if a trouble such as a power outage occurs on the power supply side, it is necessary to set the temperature from scratch, but the temperature setting circuit works safely, so it is different from the conventional case. This eliminates the risk of getting burned by hot water suddenly coming out, which is especially useful in instantaneous water heaters.

Note that in the above example, the output is switched for each terminal.
Although the explanation has been given using an IC as an example, it goes without saying that the present invention is also effective when an IC that can obtain an almost linearly variable output from one output terminal is used for temperature setting.

[Brief explanation of the drawing]

Figure 1 is a basic configuration diagram of the present invention, Figure 2 is a circuit diagram showing a specific example thereof, Figure 3 is a configuration diagram showing one embodiment of a reset circuit, and Figure 4 is a diagram showing another embodiment of the reset circuit. FIG. 2... Temperature setting circuit, 4... Reset circuit, 6
...Temperature setting switch, 7...IC.

Claims (1)

[Scope of utility model registration request] A temperature setting circuit IC that sets the temperature by emitting an output according to the operation of a temperature setting switch, and a reset that issues a reset signal to the reset terminal of the IC by applying operating power and resets the output of the IC to the low temperature output side. A temperature setting device for a hot water appliance, characterized in that both circuits are connected to the main power source before the operation switch.