KR100921945B1 - Apparatus for sensing chemical exhaustion - Google Patents

Abstract

The present invention relates to a drug exhaustion detection apparatus, wherein the drug exhaustion detection device for detecting the exhaustion of the drug when the drug contained in a predetermined container according to the present invention is supplied through a predetermined passage, the drug is moved At least one condenser is formed by attaching and disposing electrode plates facing each other or adjacent to each other on the outside of the passage, and detecting whether the drug is exhausted by changing the capacity of the at least one condenser. do. According to the present invention, it is possible to detect whether the drug is exhausted at low cost.

Ring gel, capacitor, dielectric constant, comparator, amplitude, sine wave

Description

Apparatus for sensing chemical exhaustion

1 is a schematic diagram of a general Ringer's solution injection device,

2 and 3 is a schematic view showing the configuration of a condenser of the drug exhaustion detection apparatus according to the present invention,

4 to 7 are block diagrams according to embodiments of the drug exhaustion detecting apparatus employing the capacitors of FIGS. 2 and 3 and 9, respectively.

8 is a schematic view showing another configuration of the condenser of the drug exhaustion detecting apparatus according to the embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

110: input signal generator 120: capacitive converter

130: gain calculator 132: peak detector

134: comparator 140: warning sound generating unit

C: condenser

The present invention relates to a drug burnout detection device, and more particularly to a drug burnout detection device for generating a warning sound when the drug is exhausted by detecting whether the drug is exhausted during the drug supply process.

In general, hospitals and the like are currently injecting a ring gel injection solution (ringer solution) contained in a bottle or plastic pack to a patient through a thin tube. The ring gel injector serves to supply the patient with a drug in a bottle for a long time, and is shown in FIG. 1.

As shown in FIG. 1, the ring gel injection device includes a bottle 10, a connection pipe 20, and a transfer vinyl pipe 30.

The bottle 10 provides a space for accommodating the injection liquid, and is generally supplied by the pharmaceutical company in a sealed manner with the injection liquid. The bottle is used to provide a space for accommodating the injection liquid, but may be configured in the form of a plastic pack.

The connecting pipe 20 and the conveying vinyl pipe 30 are supplied in one piece. One end of the conveying vinyl pipe 30 is provided with a human injection needle for injection into the blood vessel of the patient.

The connecting tube 20 is provided with a ring gel injection needle for injecting into the bottle 10, the injection solution is provided in the conveying vinyl pipe 30 to adjust the width of the conveying vinyl pipe to control the feed rate of the injection liquid Speed regulators and the like can be provided. The injection medicine contained in the bottle 10 is supplied to the patient through the bottle 10, the connecting pipe 20, and the transfer vinyl pipe 30. The drug supplied from the bottle has a structure that is supplied to the patient through the conveying vinyl pipe 30 while remaining in the connecting pipe 20 in a predetermined amount.

The ring gel injection device is well known to those skilled in the art, the structure and operation of the ring gel injection device will not be described further.

As described above, the ringer plunger should be removed or replaced with a new bottle when the injection solution in the bottle 10 is exhausted. If the injection solution is exhausted for a long time (10 minutes or more), the medical accident occurs due to blood backflow or air injection, or the patient cannot be properly supplied to the patient. It acts as a factor.

When all of the drugs in the bottle 10 are exhausted, all of the drugs in the connecting pipe 20 are exhausted after a certain time, and then all of the drugs remaining in the transporting vinyl pipe 30 are supplied to the patient. Will be exhausted. It is known that the time required for the backflow of the blood to be exhausted because all the drugs remaining in the conveying vinyl pipe 30 is exhausted is approximately 5-6 minutes. Therefore, the drug must be replaced within 5-6 minutes after the drug in the connecting pipe 20 is exhausted.

In case of an emergency, an expensive device is used to determine whether the drug is exhausted.However, in the case of a general patient, a guardian, a neighbor, or a nurse can always know whether or not the drug is exhausted. The inconvenience is that you have to watch.

Accordingly, it is an object of the present invention to provide a drug burnout detection device that can overcome the above-mentioned conventional problems.

Another object of the present invention to provide a drug exhaustion detection device that can detect whether the drug is exhausted.

Still another object of the present invention is to provide a drug exhaustion detecting apparatus capable of detecting drug exhaustion at low cost.

Another object of the present invention to provide a drug exhaustion detection device that can reduce the power consumption.

According to an embodiment of the present invention for achieving some of the above technical problems, the drug exhaustion detection device for detecting whether the drug is exhausted when supplying the drug contained in the predetermined container according to the present invention through a predetermined passage At least one condenser is formed by attaching and disposing electrode plates facing each other or adjacent to each other on the outside of a passage through which the drug moves, and whether the drug is exhausted by changing the capacity of the at least one condenser. It is characterized by detecting.

When the passage through which the drug moves is a circular tube, the electrode plates constituting the condenser are semicircular, and two electrode plates surround the tube from the outside and are spaced apart from each other and are attached to each other. It is possible to configure a capacitor.

The drug exhaustion detecting device may further include: a capacitance converter configured to output an amplitude or a phase of an input signal according to the capacitance of the capacitor; A gain calculation unit for determining whether or not the drug is exhausted by comparing the gain of the output signal output from the dose conversion unit with a reference gain level; An alarm generating unit may generate an alarm in response to an alarm generating signal output from the gain calculating unit. The input signal may be any one selected from sine wave, stair wave, square wave, and triangle wave.

The capacitive converter may include a resistor provided between an input node to which the input signal is input and an output node to which the output signal is output, and the capacitor provided between the output node and ground, wherein the resistor is provided. It is also possible to change the position of the and condenser. The gain calculating unit includes: a peak detector for detecting an amplitude using peak values of output signals appearing at both ends of the capacitor; A comparator may be provided that compares the amplitude detected by the peak detector with a reference amplitude level and outputs the alarm generation signal when the amplitude is greater than or equal to the reference amplitude level.

On the other hand, the gain calculating section, an AD converter for digitally converting the output signal; It may be provided with a microcontroller for outputting the alarm generation signal when the output of the AD converter compared to the existing amplitude level and the reference amplitude level or more. On the other hand, the gain calculation unit, a first comparator for outputting a phase value comparing the input signal based on the existing comparison level, and a phase value comparing the output signal of the capacitance conversion unit based on the existing comparison level And a second comparator for outputting and a microcontroller for detecting a phase difference between the first comparator output and the second comparator output and outputting the alarm generation signal when the phase difference is below a reference phase level. The gain calculating unit may include a first AD converter for digitally converting the input signal; A second AD converter for digitally converting the output signal of the capacitor converter; The alarm generation signal is output when the amplitude of the output signal of the second AD converter is equal to or greater than the existing amplitude level. When the amplitude of the output signal of the second AD converter is less than the reference amplitude level, the second AD of the first AD converter is output. A microcontroller may be provided to output the alarm generation signal only when the phase difference of the converter output is equal to or less than the reference phase level. In addition, the detection of drug exhaustion through the drug exhaustion detection device may be performed at regular cycle intervals.

On the other hand, at least two of the electrode plates constituting the condenser are provided, each of the electrode plate is provided in a form that completely surrounds the passage through which the drug moves or a portion to completely expose the passage, It may be attached adjacent each other in the longitudinal direction to the outside of the passage. In addition, when the passage through which the drug moves is a circular tube, the electrode plates constituting the condenser may have a 'C' shape or a '0' shape surrounding the tube.

According to the above configuration, it is possible to detect whether the drug is exhausted at low cost.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, without any other intention than to provide a thorough understanding of the present invention to those skilled in the art.

2 and 3 show the configuration of the capacitor used in the drug exhaustion detection apparatus of the embodiments of the present invention. 2 is a front view showing the structure of a capacitor, and FIG. 3 is a sectional view.

In general, a capacitor is composed of two electrode plates and a dielectric material provided between the two electrode plates. In this case, the capacitance value of the capacitor is expressed as 'C = ε * s / d', where ε represents the dielectric constant of the dielectric material, s represents the cross-sectional area of the electrode plate, and d represents the length between the electrode plates.

As shown in Figures 2 and 3, the condenser (C) is configured by attaching two electrode plates (40a, 40b) to the outer side of the transfer vinyl pipe 30 or the connection pipe 20 of the ring gel injection device. . In this case, the two electrode plates 40a and 40b may be disposed to face each other and may be attached to a structure surrounding the outside of the transfer vinyl pipe 30 or the connection pipe 20. The length or width of the electrode plate may be set to an appropriate length and width through experiments.

2 and 3 illustrate the case of implementing the conveying vinyl pipe 30, but the case of the case of implementing the connecting pipe 20 is not different from those of ordinary skill in the art to which the present invention pertains. It is obvious. Hereinafter, the term "cold pipe 30" is referred to collectively as the transfer vinyl pipe 30 and the connecting pipe 20.

When the two electrode plates 40a and 40b are installed in the tube 30, the two electrode plates 40a and 40b are electrically operated as the capacitors C. That is, it operates as a capacitor C whose capacitance varies depending on the dielectric material between the two electrode plates 40a and 40b. When no drug passes through the tube 30, only air exists between the two electrode plates 40a and 40b, so that the capacitance value of the condenser C becomes small, and when the drug exists, the dielectric constant of the drug is present. Since this is generally larger than air, the capacity value of the condenser C will be large.

For example, the dielectric constant (ε) is calculated by the product of the relative dielectric constant and the dielectric constant (ε _O = 8.854 × 10 ^-12 C ² / Nm ² ), the relative dielectric constant of air is '1' and the relative dielectric constant of water is It's about 78.5. Since the drug including the ring gel injection solution generally contains various components in addition to water, the relative dielectric constant is generally larger than that of the water. Therefore, by comparing the capacity change of the condenser (C) based on the water or based on a specific dielectric constant between the air and water, it is possible to know whether or not the drug is present in the tube (30). Will be.

2 and 3, the following problems may occur when attaching the electrode plate to the tube. In particular, there is no problem in the case of forming a condenser in the connecting pipe 20, but a problem may occur in the case of forming a condenser in the vinyl pipe 30 having a relatively small thickness.

When the size of the hole through which the drug passes is smaller than the overall thickness of the tube 30, the capacitance formed by the material of the tube 30 (for example, a plastic material) and the capacitance formed by the drug This structure has a structure connected directly. At this time, the change in capacitance according to the presence or absence of the drug may be difficult to determine the change in capacity.

For example, if the dose formed by the tube 30 is called 'Cp' and the dose formed by the drug is 'Cg', the total dose can be calculated as the two doses are directly connected. Therefore, the total capacity is '(Cp * Cg) / (Cp + Cg)'. Therefore, it can be seen that the change in the total dose with or without the drug is small.

Another problem is that the size of the electrode plate cannot be made large. In general, the larger the area of the electrode plate is, the larger the capacitance becomes. Therefore, it is advantageous to form a capacitor by increasing the area of the electrode plate. However, when the thickness of the tube 30 is small, it is difficult to form a capacitor with a large capacitance and there is a problem in that it is not easy to attach the electrode plate. In order to solve this problem, a new capacitor may be needed. This will be described with reference to FIG. 8.

8 shows the structure of a capacitor formed when the thickness of the tube 30 is small, and a perspective view (a) and a cross-sectional view (b) are shown.

As shown in FIG. 8, two electrode plates 50a and 50b are arranged adjacent to each other in the longitudinal direction of the tube 30 in the tube 30.

That is, each of the electrode plates 50a and 50b exposes a portion of the electrode plate 50a and 50b without completely enclosing the tube 30, which is a passage through which the drug moves, and is adjacent to each other in the longitudinal direction to the outside of the tube 30. Each may be attached in the same structure. The electrode plates 50a and 50b may have a 'C' shape for such a structure.

As another structure, although not shown in the drawings, the capacitors may be configured by arranging electrode plates having a structure completely surrounding the tube 30 to be adjacent to each other in the longitudinal direction of the tube 30. In this case, the electrode plates may be configured in a '0' shape. The electrode plates may be configured in the form of a ring or a ring surrounding the tube 30.

When the passage through which the drug moves has a shape of another polygon instead of a circular tube, the electrode plate is formed to have the same structure as that of the passage, and the electrode plate completely surrounds the passage. The passage may be attached in such a way as to partially expose the passage. In the case of the '0' shape, it would be advantageous to configure the condenser in the fixed type, and in the case of the 'C' shape, it would be advantageous in the case of the detachable condenser.

When the condenser of the electrode structure described above is configured, the capacity change according to the presence or absence of the drug is larger than that of the condenser structure of FIGS. 2 and 3, and thus, signal processing is easy and attachment is also easier.

Two or more of the electrode plates 50a and 50b may be arranged in the same form. If two or more electrode plates are arranged, a single capacitor is configured, and when three or more electrode plates are attached, the electrode plates 50a and 50b may vary according to the selection of the electrode plate. It would be possible to construct a capacitor and a variable number of capacitors.

At least one condenser described above may be configured in the tube 30. The condenser having the structure described in FIGS. 2 and 3 may be configured in the connection pipe 20, and the condenser described in FIG. 8 may be provided in the vinyl pipe 30. In the case where a plurality of capacitors are provided, they may be connected in parallel to increase the capacity.

4 is a block diagram of a drug exhaustion detecting apparatus 100 according to an embodiment of the present invention, which is configured by using a condenser having the structure described with reference to FIGS. 2 and 3 and 8.

As shown in FIG. 4, the drug exhaustion detecting apparatus 100 according to an embodiment of the present invention includes a dose converting unit 120 and a gain calculating unit 130. An input signal generator 110 may be provided to input an input signal to the capacitance converter 120, and a warning sound generator for generating a warning sound in response to an alarm signal output from the gain calculator 130. 140 may be further provided.

The capacitance converter 120 outputs the amplitude or phase of the input signal Vs according to the capacitance of the capacitor C. The capacitance converting unit 120 includes a resistor R and the capacitor C.

The resistor R is provided between the input signal generator 110 and the gain calculator 130 to which the input signal Vs is input. In other words, the resistance value is provided between the input node of the input signal Vs and the output node n of the capacitance converter 120. The resistance value may be set to an appropriate value.

The condenser C is configured as described with reference to FIGS. 2 and 3.

The capacitive converter 120 connects an electric wire to the electrode plates 40a and 40b of FIGS. 2 and 3 to ground the wire connected to one electrode plate 40b, and is connected to the other electrode plate 40a. May be configured to be connected to the resistor R, and an input signal Vs generation unit may be connected between the resistor R and the ground.

The input signal Vs may be a sinusoidal wave or a staircase. In addition, a square wave to which the staircase wave is periodically applied may be the input signal Vs, and a triangular wave may be used instead of the sinusoidal wave.

It is assumed that the input signal Vs is a sinusoidal wave Vs (t) = sin (2π * 1000) t, the resistance R = 3kΩ, and in the case of air, the capacity of the capacitor C (C = 1000pF). (C) The outputs of the capacitance converter 120 appearing at both ends are as follows.

The output of the capacitance converter 120 is 'Vo (jω) / Vs (jω) = 1 / (1 + jωRC)', and the magnitude of the output when the dielectric material is air is approximately '1'. ', And the phase becomes' -arctan (ωRC) = -1.1 ° ^| When the dielectric material is (H ₂ O), the capacitor (C) has a capacity of 'C = 78.5 * 1000pF', a size of approximately '0.56', and a phase of '-arctan (ωRC). ) = -55.9 ° '.

As described above, when the dielectric material is water, the capacity converting unit 120 has a size of approximately 1/2 and a phase difference of 55.9-1.1 = 54.8 ° when the dielectric material is water.

When the input signal Vs is a stepped file having an amplitude of 'A ^| , the output signal Vo that appears across the capacitor C is' Vo (t) = A (1-e ^{(-t / RC)} )' Appears. Since the time constant of the output signal Vo appearing on both ends of the condenser C is 'RC', it is possible to detect whether the drug is exhausted by comparing the output according to the change of the capacity of the condenser C.

Although not shown in the drawing, according to another configuration example of the capacitor converter 120, a configuration in which the positions of the resistors R and the capacitors C are exchanged may be arranged. That is, the capacitor C is provided between the input note of the input signal Vs and the output node n of the capacitive converter 120, and the resistance is provided between the output node n and the ground. It may be provided. At this time, the output of the capacitance converter 120 becomes 'Vo (jω) / Vs (jω) = jω RC / (1 + jωRC)'.

In this case, since the output of the capacitance converter 120 changes according to the change in the capacity of the condenser C, it is possible to detect whether the drug is exhausted through the output comparison according to the change in the capacity of the condenser C. do.

The gain calculator 130 determines whether the drug is exhausted by determining whether the drug is exhausted by comparing the gain of the output signal Vo output from the dose converter 120 with a reference gain level.

For example, when the dielectric material is water (H 2 O), compared to the case of air, the size is reduced to '1/2' and the phase difference is '55 .9-1.1 = 45.8 ° '. The drug is used to determine whether it is exhausted. Since the drug is known to have a higher dielectric constant than the water, the reference amplitude level and the reference phase can be set based on water. For example, set an existing amplitude level to '(1-0.56 / 2) = 0.72' with approximately 50% margin based on the water, and set the reference phase level to '54 .8 / 2 = 27.4 ° '. It is possible to set. Therefore, when the output signal Vo of the dose converter is greater than 0.72, it may be assumed that there is no drug, that is, the drug is exhausted. When the phase difference is less than 27.4 °, the drug is exhausted. Can be assumed.

The gain calculation unit 130 for detecting whether the drug is exhausted using the reference level as described above may be variously configured.

As shown in FIG. 4, the drug exhaustion detecting apparatus 100 according to an embodiment of the present invention is a device for detecting drug exhaustion using amplitude, and the gain calculating unit 130 has a peak detector 132. ) And a comparator 134.

The peak detector 132 detects an amplitude using a peak value of the output signal Vo appearing at the output node n. Instead of the peak detector 132, a full-wave rectifier circuit and a low pass filter may be provided.

The comparator 134 compares the amplitude detected by the peak detector 132 with a reference amplitude level (for example, '0,72') to generate the alarm signal when the amplitude is greater than or equal to an existing amplitude level. . When the alarm generation signal is generated in the comparator 134, the alarm sound generating unit 140 generates a warning sound.

5 is a block diagram of the drug exhaustion detecting apparatus 200 according to another embodiment of the present invention constructed by using the condenser C. Referring to FIG.

As shown in FIG. 5, the drug exhaustion detecting apparatus 200 according to another embodiment of the present invention, as shown in FIG. 4, detects drug exhaustion by using the amplitude of the output signal Vo. And a capacitance converter 120 and a gain calculator 230.

An input signal generator 110 may be provided to input an input signal to the capacitance converter 120, and a warning sound generator configured to generate a warning sound in response to an alarm signal output from the gain calculator 230. 240 may be further provided.

Since the input signal generator 110, the capacitor converter 120, and the warning sound generator 240 are the same as described with reference to FIG. 4, a description thereof will be omitted.

The gain calculator 230 may include an AD converter 232 and a microcontroller 234.

The long AD converter 232 digitally converts and outputs the output signal Vo appearing at the output node n.

The microcontroller 234 compares the output of the AD converter 232 with a reference amplitude level (for example, '0.72') and outputs the alarm generation signal when the reference amplitude level is higher than the reference amplitude level. When the alarm generation signal is generated, the warning sound generating unit 240 generates a warning sound. This can be seen that the drug is exhausted.

Figure 6 is a block diagram of a drug exhaustion detection device 300, which is another embodiment of the present invention constructed using the condenser (C).

As shown in FIG. 6, the drug exhaustion detection apparatus 300 according to another embodiment of the present invention is a device for detecting drug exhaustion by using a phase difference of the output signal Vo, and a capacity conversion unit ( 120 and a gain calculation unit 330.

An input signal generator 110 may be provided to input an input signal to the capacitance converter 120, and a warning sound generator configured to generate a warning sound in response to an alarm signal output from the gain calculator 330. 340 may be further provided.

Since the input signal generator 110, the capacitance converter 120, and the warning sound generator 340 are the same as described with reference to FIG. 4, a description thereof will be omitted.

The gain calculator 330 includes a first comparator 332, a second comparator 334, and a microcontroller 336.

The first comparator 332 outputs a phase value obtained by comparing the input signal Vs based on a reference comparison level. Here, the reference level when the input signal VS is a sine wave may be '0V'. When the input signal Vs is a square wave or staircase wave, the reference level may be determined as a constant value (for example, a value 1/2 times the amplitude of the input signal Vs).

The second comparator 334 outputs a phase value obtained by comparing the output signal Vo appearing at the output node n based on the reference comparison level. Here, the existing level when the input signal Vs is a sine wave may be '0V'. When the input signal VS is a square wave or a stepped wave, the reference level may be determined as a constant value (for example, a value 1/2 times the amplitude of the input signal Vs).

The microcontroller 336 detects a phase difference between the output of the first comparator 332 and the output of the second comparator 334. The outputs of the first comparator 332 and the second comparator 334 have time differences with each other according to the capacitance of the capacitor C constituting the capacitance converter 120.

For example, the output of the second comparator 334 is later than the output of the first comparator 332 according to the capacitance difference of the capacitor C. A time difference occurs between the output of the side first comparator 332 and the output of the second comparator 334.

In general, the larger the capacitance of the capacitor C, the larger the time difference (phase difference). In the microcontroller 336, the time difference is compared to the reference phase level (for example, 27.4 degrees). When the level is lower than the alarm output signal. When the alarm generation signal is generated, the warning sound generating unit 340 generates a warning sound. This can be seen that the drug is exhausted.

7 is a block diagram of a drug exhaustion detecting apparatus 400 according to another embodiment of the present invention constructed by using the condenser (C).

As shown in FIG. 7, the drug exhaustion detecting apparatus 400 according to another embodiment of the present invention is a device for detecting drug exhaustion by using a phase difference and a magnitude of the output signal Vo, and converting the dose. The unit 120 and the gain calculation unit 430 is provided.

An input signal generator 110 may be provided to input an input signal to the capacitance converter 120, and generate a warning to generate a warning sound in response to an alarm generation signal output from the gain calculator 430. The unit 440 may be further provided.

Since the input signal generator 110, the capacitance converter 120, and the warning sound generator 440 are the same as described with reference to FIG. 4, a description thereof will be omitted.

The gain calculator 430 includes a first AD converter 432, a second AD converter 434, and a microcontroller 436.

The first AD converter 432 digitally converts the input signal Vs and outputs the digital signal.

The second AD converter 434 digitally converts and outputs the output signal Vo appearing at the output node n.

As described above, when the drug is present, the capacitor capacity is increased than when the drug is not present and is exhausted. Therefore, the amplitude of the amplitude is smaller and the phase difference is larger when the drug is present than when the drug is exhausted. .

In the microcontroller 436, if the amplitude of the output signal of the second AD converter 434 is greater than or equal to a reference amplitude level (for example, 0.72), the microcontroller 436 detects that there is no drug and detects the alarm generation signal. Output

Next, when the amplitude of the output signal of the second AD converter 434 is less than the existing amplitude level (for example, 0.72), the output signal of the first AD converter 432 and the output signal of the second AD converter 434 may be adjusted. Find the time difference between the highest and lowest values. The time difference between the two signals corresponds to the phase difference. When the phase difference is less than the reference phase level (for example, 27.4 degrees), it is determined that the drug is exhausted and generates the alarm generation signal. Of course, when the phase difference exceeds the reference phase level (for example, 27.4 degrees), the alarm generation signal is not generated. When the alarm generation signal is generated, the warning sound generating unit 440 generates a warning sound. This can be seen that the drug is exhausted.

The drug exhaustion detection apparatuses 100, 200, 300, and 400 as described above may be operated at regular cycle intervals. In the case of a ring-gel injection device, in general, even if the injection liquid disappears from the connecting pipe 20, the drug can be injected for about 5 to 6 minutes only with the drug present in the transport vinyl pipe 30, and thus the drug exhaustion detection devices ( When the 100, 200, 300, and 400 operate with a specific time period of 5 minutes or less, power consumption may be reduced.

As described above, according to the drug exhaustion detection apparatus according to the embodiments of the present invention it is possible to easily know whether or not drug exhaustion. It is also simple to implement, has a low cost, and has the advantage of reducing power consumption.

Drug exhaustion detection device as described above can be used in any drug supply device or means for supplying drugs through a thin pipe. In addition to ring gel injection devices used in hospitals, it is applicable to all drug supply devices that need to detect drug exhaustion.

The description of the above embodiments is merely given by way of example with reference to the drawings for a more thorough understanding of the present invention, and should not be construed as limiting the present invention. In addition, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the basic principles of the present invention.

As described above, according to the present invention, there is an effect that it is easy to know whether the drug is exhausted. It is also simple to implement, low cost, and has the advantage of reducing power consumption.

Claims (13)

In the drug exhaustion detection device for detecting the exhaustion of the drug in the case of supplying the drug contained in the predetermined container through a certain passage: Outside of the passage where the drug is moved, the two electrode plates adjacent to each other in the longitudinal direction of the passage is attached to form a condenser, and detecting whether the drug is exhausted by the change in the capacity of the condenser, Each of the electrode plates has a structure that completely surrounds the passage through which the drug moves or form a portion to completely expose the passage, the drug exhaustion detection apparatus, characterized in that disposed adjacent to each other in the longitudinal direction of the passage. delete delete delete delete delete delete delete delete delete delete delete The method according to claim 1, In the case where the passage of the drug is a circular tube, the electrode plate constituting the condenser comprises a 'C' shape or '0' shape surrounding the tube characterized in that the drug exhaustion detection device.

Images