JPH06294669A - Droplet counter - Google Patents

Abstract

PURPOSE:To provide a droplet counter for counting the droplets of transparent liquid, as well as opaque liquid, accurately and quite easily. CONSTITUTION:Measuring liquid 2 can be injected into a drip unit 1 and dropped in the form of a droplet through a dripping part 3. A pair of electrodes 5a, 5b are disposed in the dripping path of the dripping liquid 4 through a gap shorter than the diameter of the dripping liquid 4. One electrode 5a is connected with a power supply while the other electrode 5b is connected with a detection resistor 6 and applied with a voltage Vcc. The detection resistor 6 is connected with a circuit 7 for converting the signal from the detection resistor 6. Furthermore, the conversion circuit 7 is connected with a circuit 8 for controlling the signal therefrom and control circuit 8 is connected with an operating panel 9 and a display 10 for presenting the count of the droplets, etc.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a droplet counter which is attached to a dispenser or the like which needs to discharge an accurate amount of liquid and which counts the liquid droplets from a discharge port. More specifically, it relates to the detection unit of the droplet counter.

[0002]

2. Description of the Related Art Conventionally, for example, a liquid drop counter has been disclosed in Japanese Utility Model No. 6
As shown in Japanese Patent No. 2-109271, an optical detector in which a light-emitter such as an LED and a light-receiver such as a photodiode are combined is used for a droplet detection unit.

In such a liquid drop counter, when a liquid drop passes between the elements of the light emitter and the light receiver, the light projected by the light emitter is blocked by the liquid drop, and the amount of light received by the light receiver decreases. To do. Therefore, the output signal level of the light receiver changes, and the droplet is detected by capturing the change in the output signal level.

[0004]

However, in the droplet counter using the optical detector as described above, in the case of non-transparent droplets having a high light reflectance, the amount of light received by the light receiver is reduced. It was possible to detect droplets because the output signal level greatly decreased, but it was possible to detect droplets, but in the case of a transparent body with a low light reflectance, such as water droplets, the light receiver The amount of light emitted is almost unchanged,
Therefore, it is difficult to detect the droplet because the output signal level does not change.

Further, since the optical detector is easily affected by ambient light such as sunlight or indoor light, malfunction is likely to occur, and in order to prevent such malfunction, special measures are taken in the optical section and the electric circuit section. Was needed.

The present invention has been made in order to solve the above-mentioned problems, and extremely simply counts the droplets of a transparent liquid as well as a non-transparent liquid. It is an object of the present invention to provide a droplet counter that can be used.

[0007]

In order to achieve this object, a droplet counter of the present invention is provided in a droplet dropping path and has a pair of electrodes opposed to each other at an interval smaller than the droplet diameter. A droplet detecting means for detecting the droplets by a signal from the electrode, and a droplet counting means for counting the number of the droplets by a signal from the droplet detecting means.

[0008]

In the droplet counter of the present invention having the above-mentioned structure, the pair of electrodes are provided in the droplet dropping path and face each other at intervals smaller than the diameter of the droplet. The droplet detecting means detects the droplet based on the signal from the electrode. The droplet counting means counts the number of droplets based on the signal from the droplet detecting means.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of the droplet counter of this embodiment.

The droplet counter includes a dropping device 1, a dropping portion 3,
It is composed of a pair of electrodes 5a and 5b, a detection resistor 6, a conversion circuit 7, a control circuit 8, an operation panel 9, and a display 10.

A measuring liquid 2 can be injected into the dropping device 1, and the measuring liquid 2 is dropped in a droplet state (dripping liquid 4) from a dropping portion 3 made of a thin tube. A pair of electrodes 5a, 5b are arranged in the dropping path of the dropping liquid 4 with a distance therebetween being smaller than the diameter of the dropping liquid 4.

One electrode 5a of the pair of electrodes 5a, 5b
Is connected to the power supply, and the other electrode 5b is connected to the detection resistor 6
It is connected to the. The other end 6b of the detection resistor 6 is connected to the ground, and a voltage Vcc is applied between the pair of electrodes 5a and 5b and the detection resistor 6. One end 6 of the detection resistor 6
A conversion circuit 7 that converts a signal from the detection resistor is connected to a. Further, the conversion circuit 7 is connected with a control circuit 8 for processing the signals of the conversion circuit 7, and the control circuit 8 has an operation panel 9 for operating the apparatus and a display device 10 for displaying the number of droplets and the like. Are connected.

Next, the operation of the droplet counter will be described.

FIG. 2 is a diagram showing a temporal change in a state in which the dropping liquid is detected at the electrode, and FIG. 3 is a diagram showing an output signal of the detection resistor at that time.

The measuring liquid 2 is poured into the dropping device 1 and a start switch (not shown) on the operation panel 9 is depressed to drop the measuring liquid 2 from the dropping portion 3.

In a state where the dropped liquid 4 has not reached the pair of electrodes 5a, 5b arranged in the dropping path of the liquid 4 (FIG. 2a), the pair of electrodes 5a, 5b is in an insulating state, The potential of the one end 6a of the detection resistor 6 becomes the ground (region a in FIG. 3), and the output from the conversion circuit 7 is at the L level.

In the state where the dropped droplet 4 reaches the pair of electrodes 5a, 5b arranged in the dropping path of the dropping liquid 4 (FIG. 2b), the pair of electrodes 5a, 5b is in a conductive state from an insulating state. In this state, the output of the conversion circuit 7 changes from the L level to the H level.

Further, at the moment when the dropped liquid 4 passes through the pair of electrodes 5a and 5b arranged in the dropping path of the liquid 4, the state shown in FIG.
The droplets 4 are electrically connected between a and 5b. Then, one end 6a of the detection resistor 6 becomes the power supply voltage Vcc (c in FIG. 3).
region). Then, the output from the conversion circuit 7 maintains the H level.

Then, when the dropping liquid 4 is lowered and separated from the pair of electrodes 5a, 5b arranged in the dropping path of the dropping liquid 4 (FIG. 2d), the pair of electrodes 5a, 5b is changed from the conductive state to the insulated state. In the transition state (region d in FIG. 3), the output of the conversion circuit 7 changes from H level to L level.

After that, when the dropping liquid 4 passes through and is separated from the pair of electrodes 5a and 5b arranged in the dropping path of the dropping liquid 4 (FIG. 2e), the insulating state is restored again, and one end 6a of the detection resistor 6 is formed. Potential becomes ground (e region in FIG. 3), and the output from the conversion circuit 7 maintains L level.

As described above, one of the dropping liquids 4 is
The output of the conversion circuit 7 changes to the L level, the H level, and the L level as the pair of electrodes 5a and 5b arranged in the drip path passes.

The subsequent dropping liquid 4 is a pair of electrodes 5a, 5
When passing through b, the pair of electrodes 5a, 5b is also similarly to the above.
The output of the conversion circuit 7 also changes to the L level, the H level, and the L level with the change of the insulated state, the conductive state, and the insulated state.

A signal that changes each time the dropping liquid 4 passes is transmitted from the conversion circuit 7 to the control circuit 8. Control circuit 8
The number of droplets is counted by the change of this signal.

The control circuit 8 counts the number of droplets for a certain period of time, for example, 1 minute after the start switch (not shown) of the operation panel 9 is pressed, and after 1 minute has elapsed, the droplet count is counted. The number is displayed on the display unit 10, and the droplet counting operation is completed.

[0026]

As is clear from the above description, according to the liquid droplet counter of the present invention, it is possible to accurately and easily drop liquid droplets of transparent liquid as well as non-transparent liquid. Can be counted.

[Brief description of drawings]

FIG. 1 is a block diagram of a droplet counter of the present invention.

FIG. 2 is a diagram showing a temporal change in a state in which a dropping liquid is detected in the electrode of the present invention.

FIG. 3 is a diagram showing an output signal of a detection resistor of the present invention.

[Explanation of symbols]

 5a electrode 5b electrode 6 detection resistor 7 conversion circuit 8 control circuit

Claims (1)

[Claims] 1. A liquid drop counter for dropping a liquid in a liquid drop state and counting the number of liquid drops to be dropped, the liquid drop counter being provided in a dropping path of the liquid drops and facing each other at intervals smaller than the diameter of the liquid drops. A pair of electrodes, a droplet detecting means for detecting the droplets by a signal from the electrodes, and a droplet counting means for counting the number of the droplets by a signal from the droplet detecting means. A droplet counter characterized in that