JPH08979A - Fluid feeder - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] To provide a fluid transporter suitable for carrying. A fluid feeder main body container, a contractible fluid storage part 2 housed in the fluid supply main body container, an electrochemical cell 5 part, and two electrical contacts 1 attached to the fluid storage part 2.
2, 13 and a fluid supply end display means, the fluid storage unit 2 contracts due to the pressure of the gas generated in the electrochemical cell unit to supply the fluid in the fluid storage unit 2, and the fluid storage unit 2 contracts. Then, at the same time when the supply of the fluid is completed, the two electrical contacts 12 and 13 attached to the fluid storage unit 2 are brought into contact with each other, and the fluid supply completion display means is activated. It is possible to accurately supply a small amount of fluid over a long period of time and accurately display the end of supply by a very simple method of setting the supply amount of the fluid only by the electric current.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid feeder for supplying a small amount of fluid accurately by utilizing an electrochemical system, and more particularly to a signal for notifying the end point of the fluid feeder. It is related to the mechanism that emits.

[0002]

2. Description of the Related Art In recent years, an electrochemical system has come to be used for an infusion pump for injecting a small amount of a liquid medicine into a human body with high accuracy.

A device has been proposed which utilizes an electrochemical cell for generating a gas when a direct current is applied, and which simultaneously performs a pump function and a gas flow rate control (Japanese Patent No. 1214001). In recent years, various electrochemical infusion pumps utilizing this principle have been proposed, and when a direct current is applied to the electrochemical cell section, this method uses a gas generated in proportion to the amount of electricity supplied to generate a chemical solution. Push it out.

H. J. R. Magget's proposal (US Pat. No. 4,522,698) has an electrochemical cell in which porous gas diffusion electrodes are bonded to both sides of a water-containing ion exchange membrane functioning as an electrolyte. When hydrogen is supplied to the anode of, and a direct current is applied between the positive and negative electrodes, hydrogen becomes hydrogen ions at the anode, and the generated hydrogen ions pass through the ion exchange membrane to reach the cathode side, where hydrogen is generated. It utilizes the fact that the electrochemical reaction occurs. That is, the pressurized hydrogen generated at the cathode is used as a drive source for pushing out the piston, diaphragm, bellows and the like. It is also possible to use oxygen instead of hydrogen as a reaction substance of this electrochemical cell, and if air is used as an oxygen source to be supplied to the cathode, the structure of the infusion pump becomes considerably simple.

Further, as an improved type of this electrochemical infusion pump, a method of utilizing the electrolysis reaction of water (Japanese Patent Laid-Open No. HEI-2)
-302264) is proposed, in which the cathode is bonded to one surface of the ion exchange membrane and the anode is bonded to the other surface, or the cathode and the anode are separated on one surface so as to be insulated from each other and bonded integrally. The electrochemical cell
Hydrogen or oxygen, which is generated by electrolysis of water when a direct current is applied to both electrodes, or a mixed gas of hydrogen and oxygen is used as a pressure source of an infusion pump.

[0006] The operating principle of an infusion pump of the type that discharges a target fluid such as a drug solution by pushing the sucker of an injector using an electrochemical system is that Faraday's law is applied when a direct current is applied to the electrochemical cell. Therefore, a gas such as oxygen or hydrogen is generated in proportion to the amount of electricity supplied, so the pressure of this gas pushes the moving body in the pressure transmission unit, and then the moving body pushes the sucker of the syringe to achieve the purpose of the drug solution. To eject the fluid. The amount of gas generated at this time can be controlled very precisely by the amount of electricity (current x time) applied to the electrochemical cell section, and the amount of gas generated and the discharge amount of the target fluid such as a chemical solution have a proportional relationship. Therefore, this type of infusion pump is characterized in that the discharge amount of a target liquid such as a chemical liquid can be accurately determined. Such an electrochemical method can be used not only for an infusion pump that discharges a chemical solution or the like but also for a fluid supply device that discharges or supplies any fluid including liquid or gas.

[0007]

DISCLOSURE OF THE INVENTION In one of electrochemical type fluid feeders, a fluid is stored in a deformable bag-shaped fluid storage part, and the inner surface of the container, the outer surface of the fluid storage part, and the electrochemical part. There is a device that introduces a gas generated by applying a direct current to an electrochemical cell in a closed space surrounded by a cell and pushes a fluid storage section by the pressure of the gas to supply the fluid. In this type of fluid supplier, gas continues to be generated as long as a direct current is applied to the electrochemical cell.
It is conceivable that if the power is not stopped, the fluid storage unit will continue to be pushed even if the fluid in the fluid storage unit runs out, causing the pressure of the gas in the enclosed space to rise abnormally and causing the fluid feeder itself to be damaged by the pressure. .

However, in the conventional fluid feeder using the electrochemical method, there is no simple method for the function of notifying the "end of discharge". Normally, a timer is used to cut off the current flowing in the electrochemical cell and at the same time, let the current flow through the circuit that issues a signal that signals "end of discharge" .However, this method increases the timer itself and increases the fluid supply device. A timer has to be set each time the device is used, which has the drawback of complicating the usage.

Therefore, the present invention has been made in order to solve the above-mentioned problems of the electrochemical fluid feeder, and the purpose thereof is to be able to immediately know the end of fluid discharge and to have a simple structure. Another object of the present invention is to provide a fluid supply device suitable for carrying, which is easy to use and can be made small and lightweight.

[0010]

An electrochemical fluid feeder according to the present invention comprises a container, a fluid reservoir and a gas generator, and the fluid reservoir comprises a fluid reservoir body, an interior of the fluid reservoir, and a fluid reservoir. A fluid supply unit that communicates with the outside, a first electrical contact,
A second electric contact, and the fluid storage unit main body has an inner volume changed by the pressure of the gas, and the first electric contact and the second electric contact are provided at positions separated from each other. The gas generation unit has a power supply unit, an electrochemical cell that generates gas by energizing a direct current, a switch that starts gas generation, an electric circuit that electrically connects them, and a signal unit that issues a fluid discharge end signal. The signal portion and the second electric contact are electrically connected to the electric circuit, the first electric contact is electrically connected to the signal portion, and the container is supplied from the fluid supply portion. It has a fluid discharge port for discharging a fluid to the outside of the container, and the space surrounded by the inner surface of the container, the outer surface of the fluid storage section and the electrochemical cell is sealed, and by applying a direct current to the electrochemical cell, Introduce the generated gas into the space inside the container Due to the pressure of the gas, the fluid in the fluid storage unit is pushed out from the fluid discharge port, and the supply of the fluid in the fluid storage unit ends, and at the same time, the first electrical contact and the second electrical contact come into contact with each other, and a current flows in the signal unit. It is characterized in that a fluid supply end signal is generated, and it is particularly preferable that the container is a pressure resistant container.

Furthermore, the present invention is intended to prevent the fluid supply device from being damaged due to the pressure of the gas in the closed space rising too high by emitting a signal when the supply of the fluid in the fluid storage unit is completed. .

As the electrochemical cell portion which can be used in the present invention, generally, any cell can be used as long as it produces a gas in proportion to the amount of electricity supplied when a direct current is applied. The following cells can be used.

1) Porous metal electrodes are joined on both sides of a solid polymer cation exchange membrane, and both electrodes are in contact with water. Oxygen generated from the anode or hydrogen generated from the cathode, or oxygen and hydrogen, when electricity is applied. The mixed gas of is used. In addition, in such a water electrolysis cell, it is common to prefill water on both the anode side and the cathode side. However, since the solid polymer ion exchange membrane can absorb a large amount of water inside, it functions as an electrolyte by exhibiting a proton conductive function, and therefore water is not necessarily used on both the anode side and the cathode side. It is not necessary to put water in, and water may be put in only one of the electrodes. That is, if water is required for the electrode reaction, water is supplied from the opposite electrode side through the solid polymer ion exchange membrane.

2) Porous metal electrodes are joined to both sides of the solid polymer cation exchange membrane, the anode is in contact with water, and the cathode is in contact with air or oxygen, and oxygen generated from the anode upon application of electricity is used.

3) A porous metal electrode serving as an anode is bonded to one surface of the solid polymer cation exchange membrane, and manganese dioxide serving as a cathode is attached to the other surface of the solid polymer cation exchange membrane to utilize oxygen generated from the anode by energization.

4) A porous metal electrode as an anode is joined to one side of the solid polymer anion exchange membrane, and manganese dioxide or nickel oxyhydroxide as a cathode is attached to the other side,
Oxygen generated from the anode by energization is used.

5) Instead of using an ion exchange membrane as an electrolyte, water is electrolyzed using an acidic or alkaline electrolytic solution, and oxygen or hydrogen generated at that time or a mixed gas of both is used.

6) Molybdophosphoric acid (H ₃ PMo ₁₂ O ₄₀ · 29H ₂ O), uranylphosphoric acid (HUO ₂ PO ₄ / 4H ₂ O), antimonic acid (Sb ₂ O ₅ Water is electrolyzed using various inorganic proton conductors such as 4H ₂ O), and oxygen, hydrogen, or a mixed gas of both generated at that time is used.

[0019]

The operation of the fluid feeder using the electrochemical method according to the present invention will be described with reference to the drawings.

FIG. 1 is a view showing a cross section of a fluid feeder before the start of use. In the figure, 1 is a container, here a pressure-resistant container, 2 is a fluid storage part whose internal volume changes, and 3 is a fluid. ,
4 is a fluid discharge port. 5 is an electrochemical cell, 6 is water used for electrolysis, and gas generated from the electrochemical cell 5 passes through a passage 7 to form an inner surface of the pressure resistant container 1, an outer surface of the fluid storage unit 2 and the electrochemical cell 5. Accumulate in the enclosed enclosed space 8.
Reference numeral 9 is a battery as a power source, 10 is a resistance for adjusting a current flowing through an electrochemical cell, 11 is a switch, 12 is a first electric contact, 13 is a second electric contact, and a first electric contact 12 And the second electrical contact 13 are mounted opposite to each other and at a distance from each other. Reference numeral 14 is a signal, and 15 is a bottom portion of the fluid storage unit 2.

In using the fluid supply device according to the present invention, a fluid 3 to be supplied, such as a chemical solution, is placed in the fluid storage section 2. At this time, the first electrical contact 12 faces the portion near the fluid supply port 20 of the fluid storage unit, and the second electrical contact 13 faces the portion near the bottom portion 15 of the fluid storage unit 2 so as to face each other. Install it in a remote location.

When the switch 11 is turned on, an electric current flows through the electrochemical cell 5, and the gas generated from the electrochemical cell passes through the passage 7 and accumulates in the closed space 8. When the electricity is continued, the pressure inside the closed space 8 rises and pushes the fluid storage unit 2, so that the fluid passes through the fluid supply port of the fluid storage unit 2 and the fluid 3 is supplied from the fluid discharge port 4 of the container 1. To be done.

When the current continues to be supplied, the amount of the fluid 3 inside the fluid storage portion decreases, and the bottom portion 15 of the fluid storage portion 2 gradually approaches the fluid discharge port 4. Further, when the electrochemical cell 5 is continuously energized, the fluid storage unit 2 is completely shrunk and the discharge of the fluid is finally completed. At this time, as shown in FIG. 2, the first electrical contact 12 and the second electrical contact 13 attached to the fluid storage unit 2 come into contact with each other, and a current flows through a circuit including the power source 9 and the signal 14. If a buzzer or the like is used as the signal 14, the "end" can be notified by sound. Further, if a lamp is turned on as the signal unit 14, the "end" can be known by the eyes.

As a fluid to be infused, a drug solution is usually considered, but the use of the fluid feeder of the present invention is not limited to infusion of a drug solution, and any fluid such as liquid or gas can be used. It goes without saying that it can be used for supply.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A fluid feeder according to the present invention will be described in detail below with reference to the drawings showing its embodiments.

The structure of the fluid feeder according to the present invention is the same as that shown in FIG.

The pressure vessel 1 is made of polypropylene and has an outer diameter of 40 mm, an inner diameter of 36 mm and a length of 65 mm. The fluid storage part 2 whose inner volume changes is made of polypropylene,
A bellows type with a thickness of 0.1 mm, with an average bellows diameter of 24 m
m, the height was 60 mm, and the internal volume was 50 ml of the medicine.
The fluid supply port 20 of the fluid storage unit was provided with a hole having the same diameter as the inner diameter of the fluid discharge port of the container. The fluid reservoir 2 is placed inside the pressure container 1, and the fluid supply port 2 of the fluid reservoir
0 and the opening of the fluid discharge port 4 on the inner side of the container were aligned with each other, and the circumference of the hole serving as the fluid supply port 20 was heat-welded to integrate the container 1 and the fluid storage unit 2.

Here, the structure is such that the fluid supply port 20 of the fluid storage unit is adhered to and integrated with the fluid discharge port 4 by thermal welding, but even if it is physically integrated. Good.

After that, the electrochemical cell 5 was heat-welded to the container 1 so that the sealed space 8 was formed by the inner surface of the pressure-resistant container 1, the outer surface of the fluid reservoir 2 and the electrochemical cell.

In this case as well, the electrochemical cell section 30 and the container 1 are hermetically integrated by thermal welding, but the electrochemical cell may be hermetically integrated by screwing or attachment to the container. Further, in the embodiment, only a part of the electrochemical cell facing the inside of the container, that is, the part of the passage 7 is exposed, but the entire surface of the electrochemical cell may be exposed.

Here, a chemical liquid was used as the liquid 3 to be supplied. As the electrochemical cell 5, a commercially available Nafion 117 membrane (solid polymer cation exchange resin membrane) having a diameter of 24 mm was used as the electrolyte.
A porous platinum electrode having a diameter of 20 mm was bonded to both surfaces of the seven films by electroless plating, and the anode was in contact with water, and was a disk type having a diameter of 30 mm and a height of 8 mm. Oxygen generated from the anode upon energization was used as the gas used for pressurization, and a commercially available 3V class lithium battery was used as the power source 9.

In using the fluid feeder according to the present invention, first, the fluid reservoir 2 is filled with a chemical solution, the resistance 10 is set to 240 ohms, the switch 11 is turned on, and the battery 9 is turned on.
When a direct current is applied to a circuit including the electrochemical cell 5 and the second contact point, a current of about 12.5 mA flows through the electrochemical cell 5, so that 25 degrees Celsius and 1 atmospheric pressure of oxygen are 2 per hour. 0.5 ml is generated and accumulated in the closed space 8 through the passage 7. Since this oxygen has a pressure of 2.5 atmospheric pressure and 1 ml, the fluid storage unit 2 is pushed by this pressure and 1 ml of the chemical liquid is supplied from the fluid discharge port 4 per hour. When the electrochemical cell 5 is continuously energized, the chemical solution inside the fluid storage unit 2 gradually decreases,
At the same time, the bottom 15 of the fluid storage unit 2 is gradually discharged from the fluid discharge port 4
Approaching. When the electrochemical cell 5 is further energized, the bellows 2 of the fluid storage unit is completely reduced, and the discharge of the chemical solution is finally completed. At this time, as shown in FIG. 2, when the first electrical contact 12 and the second electrical contact 13 come into contact with each other,
Since a closed circuit is formed by the power source 5, the signal 14, the first electric contact and the second contact, and a current flows through the circuit, if a buzzer is used as the signal 14, an "end" is signaled by sound. You can Therefore, by turning off the switch 11, it is possible to stop the further generation of gas.

[0033]

The fluid feeder according to the present invention is attached to the fluid feeder main body container, the contractible fluid storage part housed in the fluid supply main body container, the electrochemical cell part, and the fluid storage part. And the fluid supply end display means, the fluid storage unit contracts by the pressure of the gas generated in the electrochemical cell unit to supply the fluid in the fluid storage unit, and the fluid storage unit contracts. At the same time that the supply of the fluid is completed, the two electrical contacts attached to the fluid storage portion are brought into contact with each other, and the fluid supply completion display means is activated.

The fluid feeder according to the present invention pushes the fluid storage portion with the pressure of the gas generated from the electrochemical cell to feed a target fluid such as a chemical solution. A very small amount of fluid can be accurately supplied over a long period of time by a very simple method of setting.

In addition, in the fluid supply device according to the present invention, when the intended fluid is supplied by starting use, current flows in a circuit including the electrochemical cell, the power supply and the second electrical contact, At the end of the supply of the target fluid, the two electrical contacts attached to the fluid storage part whose internal volume changes will contact, and current will flow to the circuit including the power supply, signal part, first contact, and second contact. Flows, and a signal to stop the fluid supply is emitted.

When a device for producing a sound such as a buzzer is used for a signal, it is heard by an ear, and when a lamp is used for a signal, it is viewed by an eye.
The "end of supply" of the target fluid can be known. Therefore, when the switch 11 is turned off, the generation of gas from the electrochemical cell is stopped, and the pressure of the gas inside the container does not increase any more, and therefore damage to the fluid feeder itself can be reduced.

Of course, as the fluid storage unit, in addition to the bellows type described in the embodiment, any shape such as a container made of extremely thin and soft plastic or a container made of rubber can be used as long as it can be deformed by applying pressure. It is possible to use any signal, and it is also possible to use any other signal other than the buzzer and the lamp as the signal section. In the embodiment, the battery and the constant resistance are used in combination as the power supply unit, but other than this, various power supplies such as the use of the battery and the constant current circuit in combination can be used.

Further, the electrochemical cell portion of the fluid feeder according to the present invention can be made extremely small, and therefore, the fluid feeder can be made small and lightweight, and can be portable. It is easy to operate and easy to use, and when it is used for supplying a medical drug solution, it is extremely easy for a patient to use.

Further, since the fluid feeder according to the present invention has a simple structure and is inexpensive, it can be used as a disposable type, and the drawbacks of the conventional infusion pump using a bellows, a diaphragm or a syringe can be eliminated. The industrial value is extremely high.

[Brief description of drawings]

FIG. 1 is a diagram showing a cross-sectional structure of a state before a supply of a chemical liquid of a fluid feeder described in Embodiment 1 according to the present invention is started.

FIG. 2 is a view showing a cross-sectional structure of a state in which the supply of the chemical liquid of the fluid feeder described in the first embodiment of the present invention is completed.

[Explanation of symbols]

 1 Pressure Resistant Container 2 Fluid Storage Section 3 Chemical Solution 5 Electrochemical Cell 12 First Electrical Contact 13 Second Electrical Contact 14 Signal

Claims (1)

[Claims] 1. A fluid feeder main body container, a contractible fluid storage unit housed in the fluid supply unit main body container, an electrochemical cell unit, and two electrical contacts attached to the fluid storage unit.
A fluid supply end display means, the fluid storage unit contracts by the pressure of the gas generated in the electrochemical cell unit to supply the fluid in the fluid storage unit, and the fluid storage unit contracts to end the fluid supply. ,
A fluid feeder characterized in that two electrical contacts attached to the fluid storage portion are brought into contact with each other to activate the fluid supply end display means.