JPH0120653Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a liquid container such as a thermos flask or an airpot, which detects the amount of liquid in the container by electrical means and displays the amount of liquid.

Conventional liquid containers had the inconvenience of not being able to determine the amount of liquid inside, so recently, the amount of liquid in the container has been detected by applying a voltage between opposing electrodes provided on the container. A liquid container has been considered that is equipped with a detection circuit and a display circuit that displays the amount of liquid detected by the detection circuit.

It is preferable for the display section to display a bar graph proportional to the liquid volume or liquid level because it is easy to understand intuitively, but in conventional liquid containers, the number of bar graphs is small and it is difficult to accurately grasp the liquid volume. The drawback was that it was impossible to do so.

In other words, in order to display a bar graph, a decoder or the like is required to generate signals corresponding to each segment of the bar graph from the liquid volume measurement results, and if the number of stages of the bar graph is increased, the complexity of this decoder increases exponentially. In addition, when detecting the liquid level by electrical means, it is detected by measuring current, voltage, charging time, etc. that depend on the liquid level. Conventional liquid containers were only capable of displaying a small number of stages because the measured values were not linearly related to the liquid volume or liquid level, and correction was required for highly accurate display, further increasing costs considerably. .

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks of conventional liquid containers and to provide a liquid container that can display the amount of liquid in multiple stages.

That is, it is an object of the present invention to provide a liquid container in which the structure of the decoder is simplified, the circuit for correction is simplified, and the liquid amount can be displayed accurately even in multi-stage liquid amount display.

In order to achieve such an object, the liquid container of the present invention has the above-mentioned structure, in which a shift register is used in the output stage of the detection circuit, and the output of the shift register is displayed as a bar graph on the display section. The present invention is characterized in that it has a display circuit configured to input data to a latch flip-flop circuit provided correspondingly to each segment of the bar graph to appropriately adjust the bar graph display.

Because of this structure, the liquid container of the present invention can display liquid volume in multiple stages with a simple structure.

Examples will be described below based on the drawings.

Fig. 1 shows a cross section of the airpot. 1 is the main body of the airpot, 2 is an outer lid that is connected to the main body 1 by a hinge part 3 and can be opened and closed by swinging, and 4 is a medium bottle made of a double glass bottle housed in the main body 1. , 5 is an inner stopper that is inserted into and removed from the upper opening of this inner bottle. Inside this inner stopper 5, there is a stainless steel water lift pipe 6 hanging down from the bottom surface of the inner stopper 5.
A communication portion 8 of the water injection pipe 7 is formed to project forward, and a water stop valve 9 for preventing water leakage in the event of a fall is housed in the communication portion 8. Also, inside this inner stopper 5, a bellows pump 10 housed in the outer cover 2 is provided.
A ventilation path 12 is formed that communicates the exhaust port 10' of the container with the inside of the medium bottle 4.

A hook valve 11 is provided on the upper surface of the bellows pump 10, and the hook valve 11 is urged upward by the force of a spring 14 and is in contact with an upper push plate 13, so that an external force is applied to the push plate 13. When not working, the inside and outside of the bellows pump 10 are communicated, the bellows pump 10 is extended, and the push plate 13 is pushed upward. Therefore, as is known, by pushing the push plate 13, the hook valve 11 is closed and the bellows pump 10 is compressed, and the air from the bellows pump 10 is sent into the medium bottle 4 through the ventilation path 12. This pressure causes the liquid in the medium bottle 4 to flow into the water injection pipe 7.
The air port of this embodiment is configured so that the water is discharged from the outlet of the water injection pipe 15 and guided to the outside through the water injection auxiliary pipe 15.

Reference numeral 16 is a liquid crystal display provided on the front surface of the water filling cover 17 to display the liquid level, and has a liquid level display section that displays the liquid level in seven levels and a battery display section that indicates whether the battery is normal. It is.
Reference numeral 18 denotes a battery storage section formed on the lower side of the hinge section 3.As will be described later, the circuit configuration of this display device includes an aluminum tape 19 attached to the stainless steel water pumping pipe 6 around the outer periphery of the medium bottle. The liquid level is detected by measuring the capacitance between the pipes, and the pump pipe 6 is connected to a metal member 20 provided around the inner stopper 5 in order to be connected to the display circuit side. A cut-and-raised portion 21 is formed in a part of this metal member 20, and this cut-and-raised portion 21 is connected to the display circuit side so as to come into contact with a connecting piece 22 provided at the opening of the inner bottle. It is configured.

Next, the display device will be explained based on FIG. 2 and subsequent figures. Reference numeral 23 is a clock pulse oscillator using a crystal oscillator or ceramic oscillation; 24 is a measurement start pulse generation circuit that generates a liquid level measurement start pulse from the clock pulse;
From there, a clock pulse as shown in FIG. 4A is oscillated, and the measurement start pulse generating circuit 24 generates a measurement start pulse as shown in FIG. 4B in response to this clock pulse.

Reference numeral 27 is a NOT circuit with a built-in Schmitt circuit, and the input potential level at which the output changes from low level to high level is lower than the input potential level at which the output changes from high level to low level. On the other hand, it is a circuit that emits an output as shown in FIG.

The OR gate 25, the knot circuit 26, the capacitor Cx consisting of the opposing electrodes 6 and 19, and the knot circuit 27 with a built-in Schmitt circuit are configured to function as a so-called one-shot multi-circuit.

To explain the operation of this circuit, before the measurement start pulse is generated, the signal line for the pulse is connected to the fourth
As shown in Figure B, the potential at point B, which is the input side of the NOT circuit 27 with a built-in Schmitt, is pulled up to the high potential side Vdd and is at a high level.
The output of 7 is at low level.

Therefore, the two inputs of the OR gate 25 are both at low level, a low level is output from this OR gate, and the output side of the NOT circuit 26 is at a high level, so the potential at point A is at the same high level as point B. Therefore, no charge is stored in the capacitor Cx, which consists of a counter electrode provided in the liquid container. In this state, when a measurement start pulse as shown in FIG. Then, since there is no charge in the capacitor Cx, the potential at point B also decreases to a low level. At the same time as the potential at point B falls, charging starts from the high potential Vdd via the resistor R, but also at point B.
At the same time as the potential at the point becomes low level, the output of the one-shot built-in not circuit 27 becomes high level, and this high level output is sent to the OR gate 25.
is input.

Therefore, even after the start pulse falls, the output of the OR gate 25 is maintained at a high level until the output of the NOT circuit 27 becomes a low level, so that the potential at point A is maintained at a low level. Now,
The charge flowing through the resistor R charges the capacitor Cx as shown in FIG. At the same time, the output of this NOT circuit 27 becomes low level, and the OR
The output of gate 25 is set to low level. At the same time, the potential at point A becomes a high level, and for a moment the potential at point B becomes even higher due to the charged charge, but this charge escapes to the high potential power supply by diode _D1 . The voltage becomes equal to the power supply potential Vdd, resulting in a stable state. Therefore, the output of the not circuit 27 with a built-in Schmitt circuit is as shown in Figure 4 (c), and the time that this output is at a high level is the time required to charge the capacitor Cx, and the capacitance and resistance R of the capacitor are depends and therefore reflects the fluid volume. That is, as the amount of liquid increases, the capacitance increases and this time becomes longer.

Now, in order to measure this time, the output of this not circuit 27 is input to an AND gate 28 on the input side of a counter 29, and when this output is at a high level, a clock pulse passes through this gate 28 and is counted by the counter 29. By doing so, the time required for charging is measured. This counter 29
Also, this signal line is input to the reset terminal R to be reset by the measurement start pulse, and since the counter is initialized at the same time as the measurement starts, the time required for charging is output for each measurement. . The counter 29 is a shift register that sequentially outputs a high level to the higher bits each time a clock pulse is input, and the counter 30 is a shift register that outputs a high level to the gate terminal G when a high level is input. This is a latch circuit that inputs the output of and holds the value, and prevents the display from flickering during measurement.
The latch signal input to this gate is generated by the measurement start pulse generating circuit 24, and is generated after a certain time delay from the measurement start pulse, as shown in FIG. 4E. This time is the maximum time required to charge capacitor Cx and counter 2
The delay time is set from 9.

To explain the shift register 29 and latch circuit ₃₀ , they have a configuration as shown in _FIG . The shift register 29 is composed of flip-flops indicated by _{FF 11} to FF ₁₇ , and a high level output signal is output from the output terminal Q ₁ of FF ₁ to the output terminal Q ₁₀ of FF ₁₀ in order every time a clock pulse is input. Note that _FF'1 indicates a flip-flop with several stages. And when it's empty, from FF ₃
The output terminals of FF ₁₀ are all low level, and the clock pulse period is set so that all output terminals of FF ₃ to FF ₁₀ are high level when the tank is full, and the clock pulse period is set in 7 steps in proportion to the liquid volume. In order to display this, the output of the fourth flip-flop _FF4 is skipped and input to the latch circuit.

In this way, as the liquid volume increases, the latch circuit 30
From there, a high-level lighting signal is output from the output line corresponding to the lower segment of the display section 16 to the upper output line in order. This output is input to the liquid crystal drive circuit 31, which lights the display section 16 using the liquid crystal drive pulse and blinking display pulse from the latch circuit 30 and the periodic pulse generation circuit 24.

As described above, the liquid container of this embodiment is capable of displaying a liquid amount proportional to the liquid amount even with a simple structure.

In another embodiment, it is also easy to display a display proportional to the liquid level in a similar manner.

Since the display is proportional to the liquid volume or liquid level, the liquid capacity can be easily and intuitively grasped.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; Fig. 1 is a partial sectional view of the airpot, Fig. 2 is a block diagram of the display circuit, Fig. 3 is a detailed view of the main part, and Fig. 4 is a timing chart of the display circuit. be. 6, 19... Counter electrode, 23, 24, 25, 2
6, 27...Detection circuit, 29...Shift register, 30...Latch circuit.

Claims (1)

[Claims for Utility Model Registration] A counter electrode provided on a container, a detection circuit that detects the amount of liquid in the container by applying a voltage between the counter electrodes, and a liquid amount detected by the detection circuit. A liquid container having a display section that displays the liquid amount in stages as a bar graph, wherein a shift register is used at the output stage of the detection circuit, and the output of an appropriate digit of the shift register is displayed for each segment of the bar graph on the display section. A liquid container characterized in that it has a display circuit configured to provide input to a correspondingly provided flip-flop circuit for latching and to appropriately adjust the bar graph display. The counter electrode is provided so that its capacitance changes depending on the amount of liquid in the container, and the detection circuit applies a voltage to the counter electrode to determine the voltage required for charging or discharging the counter electrode by applying this voltage. The liquid container according to claim 1, wherein the liquid container is a circuit for measuring time, and the shift register is configured to output a predetermined potential up to a digit proportional to the time. A gate is provided on the input side of the shift register, through which a clock pulse is passed only while the counter electrode is being charged, and the shift register is shifted one digit at a time by the pulses passing through the gate. A liquid container according to claim 1 or 2 of the utility model registration claim characterized by: The liquid container according to any one of claims 1 to 3, wherein the appropriate adjustment is performed so that the bar graph is proportional to the liquid amount or the liquid level.