JPS6345813B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a water heater having a function of displaying the amount of remaining water.

Conventional structure and its problems Conventionally, the fifth water heater water level display means has been used.
As shown in the figure, a transparent cylinder 2 is provided with one end connected to the lower part of the container 1 and the other end connected to the upper part of the container 1, and the water level of the container 1 is indicated by the hot water in the cylinder 2. .

However, in this way, the hot water in container 1 is
If it is visible through the cylinder 2, a considerable amount of heat is radiated from the cylinder 2, resulting in large heat loss and poor efficiency both in boiling water and in keeping warm. This water level gauge cannot be used with vacuum glass pots, which are characterized by particularly good heat retention, due to heat dissipation. Therefore, the user does not know the amount of water remaining in the container, and may run out of hot water when needed, which is extremely inconvenient.

OBJECTS OF THE INVENTION The present invention takes into account the above-mentioned conventional problems and provides a water heater that has a configuration that reduces heat radiation loss and has a function of displaying the amount of water remaining inside the container.

Structure of the Invention In order to achieve the above object, the present invention includes a container for storing water, a heater for heating the container, a temperature detecting means for detecting the temperature of the container, and a temperature detecting means for detecting a temperature at which the output of the temperature detecting means reaches a predetermined value. A comparison means that outputs an output at the following times; a switch means that closes based on the output of the comparison means and is connected in series with the heater and the power source; and a switch that starts measuring time based on the output of the comparison means and outputs after a predetermined time and operates. The interior includes a timer for closing the switch means, a storage means for storing the output of the temperature detection means at the time when the timer starts operating, and an output of the storage means and the temperature detection means when the operation of the timer is completed. water amount detection means for detecting the amount of water in the container based on the output of the water amount detection means, holding means for holding the output of the water amount detection means, and display means for displaying the amount of water in the container based on the output of the holding means. It is a water heater.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on the drawings.

In FIG. 1, 1 is a container made of a material such as aluminum, and a heater 3 is wound around the lower side of the container. A temperature detecting means 4 is attached to the lower part of the container 1, and the temperature detecting means 4 and the heater 3 are electrically connected to a control section 6 located at the bottom of the outer shell 5 of the main body. In the middle of the outer shell 5 is a display means 7 for displaying the water level, which is electrically connected to the control section 6.

Figure 2 is a graph for explaining the principle of water level detection.When the heater 3 is energized, the container 1 is heated and the temperature of the water in the container 1 is raised. When the amount of water in container 1 is large, the heat capacity in container 1 is large, so the graph of water temperature versus time becomes gentle like curve A. On the other hand, when the amount of water in container 1 is small, like curve B,
It becomes a steep curve.

Therefore, if you measure the temperature of container 1 or the rate of increase in the temperature of the water in container 1 while container 1 is being heated, if the rate of temperature increase is large, the amount of water in container 1 is small, and the rate of temperature increase is small. In this case, the water level can be detected such that the amount of water in the container 1 is large.

FIG. 3 is a circuit diagram showing an example of the configuration of the control section 6, and this control section 6 is connected to the microcomputer 11.
and peripheral circuits. The microcomputer 11 shown here is composed of a CPU, ROM, RAM, input/output ports, etc., and is a so-called one-chip microcomputer.

The temperature detection means 4 is connected to the microcomputer 11 via an A/D converter 12. As a result, the temperature signal from the temperature detection means 4 is converted into a binary code and read into the microcomputer 11.

The AC power supply 13 includes a heater 3 and a triax 14.
A series circuit is connected to the triax 14, and
The structure is such that a gate current flows from a DC power source 15 through a light receiving section of a photocoupler 16.

By driving the heater control signal from the output port of the microcomputer 11 through the transistor 17 and causing a current to flow through the light emitting part of the photocoupler 16, the light receiving part of the photocoupler 16 operates, and a gate current flows from the DC power supply 15 to trigger the tryout. 1
4 is conductive.

The output port of the microcomputer 11 is connected to a display means 7 composed of multiple LEDs.

Next, the operation of the water heater configured as described above will be explained.

When the power is turned on, water boiling and water level are displayed according to the program procedure shown in the flowchart of FIG. 4 stored in the ROM in the microcomputer 11.

As shown in the flowchart of FIG. 4, when the power is turned on, the temperature of the container 1 is detected by the temperature detection means 4 in a step, and if the temperature is lower than a predetermined temperature, the heater 3 is energized in a step. Start heating step 1. Next, step memorizes the temperature T ₀ at that time, and step starts counting the timer. When the timer ends, the current to heater 3 is stopped in step, and the current temperature is
Calculate the difference △T between T ₁ and the temperature T ₀ at the start of the timer, and then in a step further calculate the water level from the difference △T from the pre-stored conversion value, store it, and then enter the next data. The value will always be output until it arrives. Then, in step, the water level output is displayed, and the process returns to step.

With the above configuration, the water heater using a microcomputer can detect the amount of water in the container without installing any device other than a temperature control device, and has a small number of parts and is highly reliable. In addition, it is possible to create an inexpensive water heater with a water flow detection function.

Effects of the Invention As is clear from the description of the embodiments above, according to the present invention, there is no need to attach a water level gauge with poor heat retention or water heating efficiency to the water heater, and it is possible to know the amount of water remaining in the water heater. can. In particular, this makes it possible to display the water level, which was previously impossible for vacuum glass pots with good heat retention, and allows you to see the amount of water remaining in the container at a glance, so you can add water in advance when necessary. It can be used in an appropriate amount, is very convenient for users, and has great industrial value.

[Brief explanation of the drawing]

Figure 1 is a schematic sectional view of a water heater as an embodiment of the present invention, Figure 2 is a characteristic diagram of container temperature and time showing the principle of water level detection, Figure 3 is an electric circuit diagram, and Figure 4 is a water level display. FIG. 5 is a flowchart showing an example of a program for temperature control. FIG. 5 is a structural diagram of a conventional water level gauge. DESCRIPTION OF SYMBOLS 1... Container, 3... Heater, 4... Temperature detection means, 7... Display means, 11... Microcomputer, 14... Triack, 16... Photocoupler, 17... Transistor.

Claims (1)

[Claims] 1 A container for storing water, a heater for heating the container, a temperature detection means for detecting the temperature of the container, a comparison means for outputting an output when the output of the temperature detection means is below a predetermined value, and the comparison means. a switch means connected in series with the heater and the power supply, which is closed by the output of the comparison means; and a timer that starts measuring time based on the output of the comparison means, outputs the output after a predetermined time, and closes the switch means during operation. and storage means for storing the output of the temperature detection means at the time when the timer starts operating, and detecting the amount of water in the container based on the output of the storage means and the output of the temperature detection means when the operation of the timer is completed. A water heater comprising a water amount detection means, a holding means for holding the output of the water amount detection means, and a display means for displaying the amount of water in the container based on the output of the holding means.