JPH0663133A - Portable automatic infusion injector - Google Patents

Abstract

PURPOSE:To provide a portable automatic infusion injector which can feed an infusion constantly by pump action, and be reduced in cost, size and weight by using a shape memory alloy as a driving source of a pump. CONSTITUTION:A portable automatic infusion injector comprises a feed unit A and a control unit B. The feed unit includes an infusion container 1, flexible tubes 3, 3 for feeding the infusion into a human body, and a micro-pump 4 which is connected to the midway of the flexible tube and discharges a fixed quantity of the infusion in response to a signal from the control unit. In the control unit, the pump 4 is removably installed, a storing part electrically connected to the pump is formed, and further a control circuit 7 for sending a signal for driving the pump in a variable designated period and a battery for supplying the power to the pump are built. As a driving source for the pump, a unidirectional or bidirectional shape memory alloy is used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for injecting a drug solution into a human body, and more particularly to a portable automatic drug solution injector capable of constantly injecting a drug solution into a human body even during daily movement. is there.

[0002]

2. Description of the Related Art When injecting a drug solution into a human body, for example, when injecting a nutritional supplement or the like through a vein, a method conventionally used is to hold a plastic container containing the drug solution at a high place, and A liquid medicine such as a nutrient solution is dropped from this container by gravity, and a control valve is provided in the path to adjust the required amount of the liquid medicine such as a nutrient solution and inject it into the human body.

[0003]

In the above method for injecting a drug solution such as a nutritional supplement, it is necessary to move the solution except when the drug solution is injected into a human body in a stationary state such as lying on a bed. When injecting a medicinal solution into a human body, the patient must move the container containing the medicinal solution by hand or while holding it at a high place with a retainer, which limits the range of activity and is troublesome. It was

Further, in the case of a patient suffering from a certain kind of disease, for example, diabetes, it is necessary to constantly inject the drug solution into the human body. There is a problem that it is inconvenient to live a life and it is impossible to constantly inject the drug solution.

Therefore, in view of the above-mentioned conventional problems, it is a first object of the present invention to provide a portable automatic drug solution injecting device capable of constantly injecting a drug solution by a pump action. There is.

A second object of the present invention is to provide a portable automatic chemical liquid injector which is inexpensive and can be reduced in size and weight by using a shape memory alloy as a drive source for a pump. .

[0007]

In order to achieve the above first object, a portable automatic liquid medicine injecting device according to the present invention is a liquid medicine injecting device for constantly injecting a liquid medicine into a living body, which stores the liquid medicine. Consists of a container, a flexible tube for injecting the liquid medicine in the container into a living body, and a micropump connected in the middle of the tube and discharging a fixed amount of the liquid medicine in response to a signal from a control unit described later. Injecting unit, the micropump of the injecting unit is detachably mounted, and a storage section electrically connected to the micropump is formed, and the micropump is driven at a variable predetermined cycle. It is characterized in that it is composed of a control circuit for transmitting an output signal for operating the control circuit and a control unit having a battery for supplying electric power to the control circuit.

In order to achieve the above second object, the portable automatic chemical liquid injector according to the present invention uses, as a driving source of the micropump, a shape memory alloy which expands or contracts by self-heating due to energization. A feature of the present invention is that a micropump is used which performs a pumping action by stretching or contracting the shape memory alloy.

In order to achieve the above-mentioned second object, the portable automatic liquid injector according to the present invention is expanded or contracted by self-heating by energization as a driving source of the micropump, and contracted by cooling by non-energization. Alternatively, it is characterized in that a shape memory alloy that expands is used and a micropump that performs a pumping action by expansion and contraction of the shape memory alloy is used.

[0010]

Since the portable automatic liquid medicine injecting device of the present invention has the above-described structure, the liquid medicine is injected by the pump action controlled by the control circuit, so that the liquid medicine injecting device can be freely moved. it can. In addition, since the injection unit is detachably attached to the control unit, when the drug solution stored in the container is exhausted, no special operation is required for the new injection unit filled with the drug solution. It is extremely hygienic because it can be replaced very easily.

Further, since the pumping action is performed by a small and lightweight micropump using a shape memory alloy and having low power consumption, it can be used for a long time with a battery and can be carried. In particular, since the shape memory alloy that is bidirectional that performs a pumping action by its expansion and contraction is adopted, it is not necessary to provide a biasing member for restoring the shape memory alloy.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a state of injecting a drug solution into a human body using the automatic drug solution injector according to the present invention.
Reference numeral 1 denotes a container for containing a chemical solution made of plastic, which is provided with an outlet for the chemical solution in the lower part and a clip 2 for holding the container in an appropriate place in the upper part.

Reference numeral 4 denotes a micropump shown in FIGS. 2 to 4 for injecting a drug solution in a container 1 into a human body, which comprises the container 1 and an injection needle 5 to be inserted into a patient's arm or the like. It is connected in the middle of the flexible tubes 3 and 3'to be connected. The container 1, the tubes 3, 3 ', the micropump 4 and the injection needle 5 described above are combined into one unit (hereinafter,
The micropump 4 is also provided with a clip 2 for holding it in place.

The reference numeral 6 designates an accommodating portion formed on the upper surface so that the micropump 4 can be removably mounted and the shape memory alloy in the micropump 4 and the control circuit 7 described later can be electrically connected in the mounted state. In the case with 6a,
A control circuit 7 for sending a pulse signal of a constant frequency that can be changed by operating an operation knob (not shown) is built in the inside thereof.

Reference numeral 8 is a battery box integrally formed in the lower portion of the case 6, and a battery as a power source for driving the control circuit 7 is housed inside the battery box. The case 6 containing the control circuit 7 and the battery box 8 are treated as one unit (hereinafter, control unit B).

Therefore, when the drug solution in use is exhausted from the container 1, the injection unit A is replaced with the control unit B.
The injection unit A can be removed and replaced with another injection unit A.

Next, an embodiment of the micropump 4 in the injection unit A will be described with reference to FIG. 9,
9'is a lid made of a material such as acrylic that is not attacked by chemicals, and has holes 9a, 9a ', near the center and the outer periphery.
9b and 9b 'are opened. And the holes 9a, 9
a'is a one-way valve 10 connected to the tubes 3, 3 ',
10 'is fitted so that the chemical solution does not flow back into the container 1.

Reference numeral 11 is a cylindrical bellows made of metal or synthetic resin for connecting the outer peripheries of the lids 9 and 9'to each other so that the lids 9 and 9'approach and separate from each other. A flexible tube 12 that is not attacked by a chemical liquid such as silicone is interposed on the inner surface, and is formed to prevent the chemical liquid from leaking.

Reference numeral 13 is a flexible tube which is not affected by a chemical such as silicone connecting the holes 9b and 9b 'of the lids 9 and 9', and 14 is arranged in the tube, and both ends are electrode rods 14a and 14a. ′ Attached, for example, Ti-Ni
Shape memory alloy wire such as wire, and electrode rods 14a, 14a '
Is connected to the control unit B via a lead wire.

Next, to explain the operation of the above-described micropump 4, when a current is supplied from the control unit B to the shape memory alloy wire 14, the shape memory alloy wire 14 self-heats and is stored in advance. The shape changes to a contracting shape. Here, when the shape memory alloy wire 14 contracts, the contracting force causes the tubes 12 and 13 and the bellows 1 to contract.
1 contracts and the lids 9 and 9'approach. Therefore, the inside of the tube 12 is in a pressurized state, and the drug solution in the tube 12 is delivered to the tube 3'through the one-way valve 10 'and injected into the human body from the injection needle 5.

When the electric current from the control unit B is cut off, the shape memory alloy wire 14 is cooled, so that the extension force of the bellows 11 causes the extension lids 9 and 9'to be separated from each other. Therefore, since the inside of the tube 12 is in a negative pressure state, the drug solution in the container 1 flows into the tube 12 via the tube 3 and the one-way valve 10.

Thereafter, the pulse current from the control unit B causes the inside of the tube 12 to be pressurized or become negative, and the supply and inhalation of the drug solution are repeated, thereby functioning as a pump. .

The size of the micropump 4 used in this embodiment is about 30 mm in length and about 16 mm in diameter.
It weighs about 5 g. Furthermore, its power consumption is about 0.2 W
Therefore, the micropump 4 is sufficiently portable and can be attached to the human body together with the drug solution container 1 and the control unit as needed. Furthermore, since it consumes less power, it can operate stably with a battery for a long time, and can constantly inject a chemical solution into the human body.

Next, another embodiment of the micropump 4 will be described with reference to FIG. The same parts as those in FIG. 2 are designated by the same reference numerals, and detailed description thereof will be omitted. In the micropump of the present embodiment, both ends of the conical body 15 made of a flexible material such as latex rubber and formed in a truncated cone shape are fixed to the case 16 made of, for example, acrylic and communicated with the respective openings. One-way valve 1 connected to tubes 3, 3 '
Attach 0 and 10 'to the case 16.

Further, both ends of the shape memory alloy plate 17 that acts in the direction of opening the contraction body 15 are attached to the inside of the contraction body 15 at a portion where the distance from the one-way valve 10 is about 1/3, and Bias springs 18, one end of which is fixed to the case 16, are connected to both ends of the shape memory alloy 17, and the connecting portions are formed in a water-like state with respect to the contracting body 15. An electrode 18a fixed to the case 16 is connected to the bias spring 18.

Next, to explain the operation of the micropump having the above-mentioned structure, FIG.
In this state, the shape memory alloy 17 is expanded and the contraction body 15 is expanded by the bias spring 18.

In this state, when the current from the control unit B is supplied to the shape memory alloy 17 via the upper and lower two bias springs 18, the shape memory alloy 17 is heated and is shown in FIG. 3 (B). The memorized shape (largely curved) is changed against the spring force of the bias spring 18. Therefore,
Since the inner volume of the contracting body 15 becomes small and the contracting body 15 is in a pressurized state, the chemical liquid contained in the contracting body 15 is unidirectional valve 10 '.
Is delivered to the tube 3 '.

When the current from the control unit B is cut off, the shape memory alloy 17 is cooled, so that the contracting body 15 expands due to the spring force of the bias spring 18, so that the contracting body 15 is in a negative pressure state. Therefore, the drug solution in the container 1 flows into the contractor 15 via the tube 3 and the one-way valve 10.

Hereinafter, the pulse signal from the control unit B causes the inside of the contractile body 15 to be pressurized or negative pressure, and the supply and inhalation of the drug solution are repeated, thereby functioning as a pump. is there.

Next, still another embodiment of the micropump 4 will be described with reference to FIG. The same parts as those in FIGS. 2 and 3 are designated by the same reference numerals, and detailed description thereof will be omitted. In the micropump of this embodiment, the insulated shape memory alloy wire 19 braided into a braided shape is covered with a rubber film 20 of a flexible material such as latex rubber, and both ends of the shape memory alloy wire 19 are electrodes 19 '. And

Both ends of the rubber film 20 are thick portions 20a formed thicker than the portion covered with the shape memory alloy wire 19, and the one-way valve 1 is formed in the thick portion 20a.
0 and 10 'are fitted and this part is fixed to both ends of the case 21. Further, the tubes 3 and 3'are connected to the ends of the thick portion 20a protruding from the case 21. The electrode 19 'of the shape memory alloy wire 19 is connected to the electrode 22 provided on the case 21 by the lead wire 19a.

Next, to explain the operation of the micropump having the above-mentioned structure, FIG. 4A shows the shape memory alloy wire 1.
9 shows a state in which no current flows, and in this state, the thick portion 2 in which the rubber film 20 has a large thickness is formed.
Due to the elastic force of 0a, the shape memory alloy wire 19 extends in the left-right direction and the diameter of the rubber film 20 is reduced.

In this state, when the current from the control unit B is supplied to the shape memory alloy wire 19 via the electrode 22 and the lead wire 19a, the shape memory alloy wire 19 is heated and the shape memory alloy wire 19 is heated as shown in FIG. The shape is changed to a memorized shape (braided shape having a large diameter) against the elastic force of the thick portion 20a. Therefore, since the diameter of the rubber film 20 becomes thicker and the inner volume becomes larger, the inside of the rubber film 20 is in a negative pressure state, and the chemical liquid in the container 1 flows in through the tube 3 and the one-way valve 10.

Then, when the current from the control unit B is cut off, the shape memory alloy wire 19 is cooled, so that the elastic recovery force of the thick portion 20a of the rubber film 20 pulls the rubber film 20 in the left-right direction to cause the rubber film 20 to move. The diameter becomes smaller. Therefore, since the inside of the rubber film 20 is in a pressurized state, the rubber film 20
The drug solution contained therein is delivered to the tube 3'through a one-way valve 10 '.

Thereafter, the pulse signal from the control unit B causes the rubber film 20 to be pressurized or negatively pressured, so that the supply and the suction of the chemical solution are repeated, thereby functioning as a pump. is there.

In the above-mentioned embodiment, the shape memory alloy wire 14 used as the driving source of the micropump 4 self-heats upon energization and resists the extension force of the bellows 11, ie, the previously stored shape, that is, When the bellows 11 is cooled by being de-energized by changing the shape of the bellows, the bellows 11 is restored to its original shape. In the case of the shape memory alloy 17, when it is cooled by de-energizing by changing the shape memory alloy 17 to a pre-stored shape against the spring force of the bias spring 18 by energization, that is, a curved shape, It is restored by the tension of the bias spring 18. Further, in the case of the shape memory alloy wire 19, the shape memory alloy 19 is applied to the thickened portions 2 at both ends of the rubber film 20 by energization.
The shape stored in advance against the elastic force of 0a, that is,
By changing the shape of the braid with a large diameter, when it is cooled by non-energization, it is restored by the elastic force of the thick portion 20a.

In short, in the above-mentioned embodiment, since the unidirectional alloy is used as the shape memory alloy, it is necessary to provide the biasing means for returning the shape memory alloy once changed to the memory shape. However, the use of bidirectional shape memory alloy eliminates the need for such biasing means.

FIG. 5 shows a modification in which the one-way shape memory alloy used as the driving source in the micropump of FIG. 2 is replaced by a two-way one. In the figure, the same parts as those in FIGS. 2 and 3 are designated by the same reference numerals, and detailed description thereof will be omitted. The bidirectional shape memory alloy coil 30 used in the micropump of this embodiment contracts due to self-heating due to energization and expands due to cooling due to non-energization to perform a pumping action. Therefore, in the embodiment of FIG. 2, the cylindrical bellows 1 made of metal or synthetic resin provided outside the flexible tube 12 for restoring the shape memory alloy 14.
1 is omitted, and the flexible tube 12 is replaced with a bellows 31 made of silicon or the like.

Next, to explain the operation of the micropump having the above-mentioned structure, FIG. 5A shows the shape memory alloy wire 1.
9 shows a state in which no current flows, and in this state, the shape memory alloy coil 30 is expanded,
When current is supplied to the shape memory alloy coil 30 in this state, the shape memory alloy coil 30 is heated and the shape memory alloy coil 30 is heated.
The compressed shape is stored as shown in FIG. When the supply of the electric current to the shape memory alloy coil 30 is stopped, the shape memory alloy coil 30 cools and expands to the memorized shape shown in FIG. 5 (A).

Therefore, the volume of the space surrounded by the bellows 31, the tube 13, and the lids 9 and 9'increases or decreases. When the vacant space is reduced, the vacant space is in a pressurized state, so that the chemical liquid contained in the vacant space passes through the tube 3'through the one-way valve 10 '.
Sent to. When the space increases, the space inside becomes negative pressure and the chemical solution flows in through the tube 3 and the one-way valve 10.

As described above, in this embodiment, the cylindrical bellows 11 made of metal or synthetic resin is used as the bias means.
By omitting, the configuration of the micropump 4 is simplified, and the size can be further reduced.

In the above-mentioned embodiment, the shape memory alloy used is one that contracts by self-heating due to energization, or one that contracts by self-heating and expands by cooling. It is also possible to use one that expands, or one that expands by self-heating and contracts when cooled.

[0043]

As described above, according to the present invention, since the micro pump is used, the chemical solution can be constantly injected, and the micro pump of the injection unit is detachably attached to the control unit. Since it is like this,
When replacing with a new injection unit, the micropump can be discarded together with the container for storing the chemical solution after using the chemical solution, and it is possible to obtain a portable automatic chemical solution injection device that is extremely easy to replace and extremely hygienic. it can.

Further, since a shape memory alloy is used as a driving source of the micropump and the pulse signal from the control circuit is supplied to the shape memory alloy to cause the pump action, the micropump is manufactured in a small size, light weight and energy saving. Therefore, it can be configured as a portable device, and since the supply amount of the chemical liquid can be adjusted by the pulse width, it is possible to obtain an effect such as accurate control.

In particular, by using a bidirectional shape memory alloy as the driving source of the micropump, the micropump can be manufactured in a further smaller size and lighter weight, and therefore the portability can be further improved. You can also get the effect that you can.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view showing the entire portable automatic injection device of the present invention.

FIG. 2 is a cross-sectional view showing an embodiment of a micropump used in the above portable automatic injecting device.

3A and 3B are cross-sectional views showing another embodiment of the micropump, FIG. 3A being before operation and FIG. 3B being after operation.

FIG. 4 shows still another embodiment of the micro pump,
FIG. 7A is a sectional view showing a state before the operation and FIG.

5A and 5B are cross-sectional views showing another embodiment of the micropump, FIG. 5A being before operation and FIG. 5B being after operation.

[Explanation of symbols]

 A injection unit B control unit 1 container 3, 3'tube 4 micro pump 6 storage part 7 control circuit 14, 17, 19, 30 shape memory alloy

Claims (3)

[Claims] 1. A drug solution injecting device for constantly injecting a drug solution into a living body, comprising: a container containing the drug solution; a flexible tube for injecting the drug solution in the container into the living body; And an injection unit configured by a micropump that discharges a certain amount of the liquid medicine in response to a signal from a control unit described later, the micropump of the injection unit is detachably attached, and the micropump is electrically connected to the micropump. A control unit which forms a storage unit to be connected and which outputs an output signal for driving the micro pump at a variable predetermined cycle; and a control unit having a battery for supplying electric power to the control circuit, A portable automatic liquid medicine injector characterized by being configured. 2. A micropump as a drive source for the micropump according to claim 1, wherein a shape memory alloy that expands or contracts by self-heating due to energization is used, and the pumping action is performed by the expansion or contraction of the shape memory alloy. A portable automatic liquid medicine injection device characterized by utilizing. 3. A drive source for the micropump according to claim 1, which expands or contracts by self-heating due to energization,
Also, a portable automatic chemical injection device is characterized in that a shape-memory alloy that contracts or expands by cooling when not energized is used, and a micropump that performs a pumping action by the expansion and contraction of the shape-memory alloy is used.