INJECTION SYSTEM USING NEEDLELESS SYRINGE

Abstract

An injection system of the present invention comprises a needleless syringe; a transfer passage which connects a first space for accommodating a plurality of injection targets and a second space as a transfer destination of the plurality of injection targets, the transfer passage being installed with the needleless syringe so that an emission port of the needleless syringe is open at inside of the transfer passage; a detecting unit which is capable of detecting transfer through the transfer passage in order for the injection target existing in the first space to go toward the second space; and a control unit which performs emission of the injection objective substance from the emission port of the needleless syringe for every injection target in accordance with the transfer of the injection target, if the transfer of the injection target is detected by the detecting unit. Accordingly, the load exerted on an operator is mitigated as far as possible and the occurrence of various problems concerning the hygiene is suppressed when the injection is performed for a large number of the injection targets such as domestic animals or the like.

Claims

1. An injection system using a needleless syringe, comprising: the needleless syringe which injects an injection objective substance into an injection target by emitting the injection objective substance from an emission port without using any injection needle; a transfer passage which connects a first space for accommodating a plurality of the injection targets and a second space as a transfer destination of the plurality of injection targets, the transfer passage being installed with the needleless syringe so that the emission port of the needleless syringe is open at inside of the transfer passage; a detecting unit which is capable of detecting transfer through the transfer passage in order for the injection target existing in the first space to go toward the second space; and a control unit which performs emission of the injection objective substance from the emission port of the needleless syringe for every injection target in accordance with the transfer of the injection target, if the transfer of the injection target is detected by the detecting unit.

2. The injection system using the needleless syringe according to claim 1, wherein the needleless syringe includes: a syringe which serves as a space for accommodating a predetermined volume of the injection objective substance; an air cylinder which has a piston formed to be capable of performing reciprocating motion by supplying and discharging pressurized air and an air valve for driving the piston and which pressurizes the injection objective substance accommodated in the syringe by means of the reciprocating motion of the piston; and a nozzle which includes the emission port for emitting the injection objective substance pressurized by the piston toward the injection target, wherein: the injection system further comprises a gas supply device which supplies the pressurized air for driving the piston in the air cylinder to the needleless syringe.

3. The injection system using the needleless syringe according to claim 2, wherein the needleless syringe includes: a first valve which allows the injection objective substance to be capable of flowing in only one direction from a vial toward the syringe in a communication passage formed between the syringe and the vial that accommodates the injection objective substance; and a second valve which allows the injection objective substance to be capable of flowing in only one direction from the syringe toward the nozzle in a discharge passage formed between the nozzle and the syringe, wherein: the injection objective substance is supplied into the syringe from the vial via the communication passage when the piston is moved backwardly in the air cylinder to provide a negative pressure in the syringe when the first valve is in an open state and the second valve is in a closed state.

4. The injection system using the needleless syringe according to claim 1, further comprising: a holding unit which is provided at the transfer passage, which temporarily stops the transfer of the injection target in the transfer passage to hold the injection target, and which allows the emission port of the needleless syringe to abut against a body surface of the injection target on the basis of a detection result of the transfer of the injection target obtained by the detecting unit.

5. The injection system using the needleless syringe according to claim 1, further comprising: an obstructing unit which obstructs the injection target having transferred from the first space to the second space from returning toward the first space, the obstructing unit being provided in a predetermined passage range disposed on a side of the second space as compared with an installation portion of the emission port of the needleless syringe in the transfer passage.

6. The injection system using the needleless syringe according to claim 5, wherein the obstructing unit is composed of a plurality of inclined plates which are inclined toward the side of the second space as compared with the installation portion of the emission port in the transfer passage and which protrude to an inner side of the transfer passage.

7. The injection system using the needleless syringe according to claim 1, further comprising: an inducing device which transfers the injection target existing in the first space to the second space via the transfer passage.

8. The injection system using the needleless syringe according to claim 1, wherein: the first space, the second space, and the transfer passage are arranged in water; and the injection target is a living body capable of existing in water.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG. 1 schematically shows an injection system using a needleless syringe according to the present invention.

[0023] FIG. 2 shows a schematic arrangement of the needleless syringe used in the injection system shown in FIG. 1.

[0024] FIG. 3 shows a schematic arrangement of a holding device used in the injection system shown in FIG. 1.

[0025] FIG. 4 shows a flow chart of an injection process executed by the injection system shown in FIG. 1.

EMBODIMENTS FOR CARRYING OUT THE INVENTION

[0026] An explanation will be made below about an injection system 1 according to an embodiment of the present invention with reference to the drawings. Note that the arrangement of the following embodiment is shown by way of example, and the present invention is not limited to the arrangement of the embodiment.

[0027] FIG. 1 shows a schematic arrangement of an injection system 1. The injection system 1 is the system for executing the injection of a drug solution or liquid medicine (corresponding to the injection objective substance of the present invention) by means of a needleless syringe 20 in order to prevent farmed fish in water from any infectious disease. Specifically, the injection of the drug solution is executed for the farmed fish during the process in which a plurality of the farmed fish existing in a first space S1 are transferred or moved to a second space S2 which is a space distinct from the first space S1. Note that in the following description of the present invention, the injection objective substance, which is injected into the injection target by means of the needleless syringe 20, is generally referred to as drug solution. However, it is not intended thereby to limit the contents and the form of the substance to be injected. As for the injection objective substance, it is allowable that the component, which is to be delivered to the farmed fish or the like as the injection target, is either dissolved or not dissolved. Further, the specified form of the injection objective substance is also insignificant, for which it is possible to adopt various forms including, for example, liquid and gel form, provided that the injection objective substance can be emitted to the injection target by means of the needleless syringe 20.

[0028] In this case, the first space S1 and the second space S2 are the spaces which are formed while being isolated from the surroundings so that the farmed fish are transferable or movable via only a transfer space 7 formed by a transfer passage 6. Therefore, the farmed fish cannot come and go between the first space S1 and the second space S2 without passing through the transfer space 7. Further, the transfer space 7 approximately has such a cross-sectional area that only one farmed fish as the injection target of the drug solution can transfer or move therethrough. Therefore, when the farmed fish are transferred from the first space S1 to the second space S2, the farmed fish passes through the transfer space 7 one by one in front of ultrasonic sensors 8a, 8b and an emission port 21 as described later on. Note that a stew (fishpond) or the like, which is generally utilized to culture or breed fish, can be exemplified as the first space S1 and the second space S2 by way of example. In this case, the two stews are connected to one another by the transfer passage 6, and thus it is possible to form the injection system 1 shown in FIG. 1.

[0029] In this case, the transfer passage 6 is formed by a first space side connecting portion 6b which is connected to the first space S1, a second space side connecting portion 6c which is connected to the second space S2, and a main passage body 6a which connects the both connecting portions. Then, the farmed fish, which exists in the first space S1, can enter the transfer space 7 from the first space side connecting portion 6b, and the farmed fish can be transferred to the second space S2 via the transfer space 7 in the second space side connecting portion 6c and the main passage body 6a. Then, an entry obstructing device 11 (this device corresponds to the obstructing unit according to the present invention), which is formed by a plurality of inclined plates inclined toward the side of the second space S2 and arranged to protrude toward the transfer space 7 from the inner wall of the second space side connecting portion 6c, is provided for the second space side connecting portion 6c. The inclined plates of the entry obstructing device 11 are inclined toward the side of the second space S2. Therefore, the farmed fish can be transferred or moved from the first space S1 to the second space S2 relatively easily. On the other hand, the entry port into the transfer space 7 is formed to be relatively small, as viewed by the farmed fish having been transferred to the second space S2. Therefore, it is possible to obstruct the farmed fish from returning from the second space S2 to the first space S1.

[0030] Further, the needleless syringe 20 is installed at the main passage body 6a. Note that when the needleless syringe 20 is installed at the main passage body 6a, a state is given, in which the emission port 21 is exposed to the transfer space 7. An exemplary structure of the needleless syringe 20 will now be explained on the basis of FIG. 2. FIG. 2 shows a sectional view illustrating the needleless syringe 20 as taken in the longitudinal direction thereof. The left side shown in FIG. 2 is the forward end side of the needleless syringe 20, on which the emission port 21 is arranged. Note that the description forward end side in this application refers to the side near to the emission port 21 as compared with the proximal end side. Therefore, the left side as viewed in FIG. 2 corresponds to the forward end side.

[0031] The needleless syringe 20 has an air cylinder including an air valve 30 which accumulates and releases the pressurized air supplied from the outside and a piston 29 which is formed to be capable of performing the reciprocating motion in a sliding hole 28 formed in a main syringe body 20a by utilizing the pressurized air. Specifically, the pressurized air is supplied to the air valve 30 via a supply tube 3 from a pressurized air supply apparatus (compressor) 2 arranged outside the syringe. Then, those provided in the air valve 30 are an accumulating chamber (not shown) which accumulates the supplied pressurized air and a releasing unit (not shown) which releases the accumulated pressurized air toward the sliding hole 28 in which the piston 29 is arranged. Note that the switching or changeover of the accumulation and the release of the pressurized air in the air valve 30 is controlled by the depression and the release of a changeover button 31. Then, the depression and the release of the changeover button 31 are executed by a solenoid startup device 4 which is driven in accordance with a startup signal fed from a control device 10 shown in FIG. 1 (this device corresponds to the control unit according to the present invention). When the solenoid startup device 4 receives the startup signal from the control device 10, then the driving current flows through a solenoid contained therein, and a plunger is driven by the magnetic force generated by the solenoid to make it possible to depress the changeover button 31. Then, the driving current is stopped, then the plunger returns, and the changeover button 31 is released from the depression.

[0032] In this arrangement, a positioning spring (not shown), which determines the relative position of the piston 29 with respect to the air valve 30, is provided between the air valve 30 and the piston 29 arranged in the sliding hole 28. Therefore, the piston 29 is movable in the sliding hole 28. However, the piston 29 is in a state in which the urging force is received from the positioning spring during the movement thereof. Note that the state shown in FIG. 2 represents the state in which the pressurized air is accumulated in the air valve 30, i.e., the state in which the pressurized air is not released from the air valve 30 with respect to the piston 29. The relative position of the piston 29 with respect to the air valve 30 in this state resides in the state in which the piston 29 is arranged on the side of the air valve 30 by means of the urging force of the positioning spring.

[0033] Further, a syringe 24, which is a space for accommodating the drug solution (injection solution or parenteral solution) to be emitted by the needleless syringe 20, is formed on the forward end side of the piston 29 (side opposite to the air valve 30) in the state shown in FIG. 2. A drug solution supply passage 25 (this passage corresponds to the communication passage according to the present invention) is open at a position at which no interference occurs with the piston 29 which makes the reciprocating motion in the syringe 24. The vial 5, which accumulates the drug solution, is connected via the first valve 26 to the drug solution supply passage 25. When the first valve 26 is in the open state, the drug solution can be supplied from the vial 5 via the drug solution supply passage 25 to the syringe 24. Note that the first valve 26 performs the regulation so that the drug solution flows in only one direction directed from the vial 5 to the syringe 24. Therefore, when the drug solution flows while being directed from the syringe 24 to the vial 5, the first valve 26 is closed by the force exerted by the flow. On this account, as for the first valve 26, the valve is pressed in the direction directed to the vial 5 by means of elastic means such a spring or the like, and the first valve 26 is normally closed. However, the opening/closing of the first valve 26 may be electronically controlled by the control device 10.

[0034] Further, the syringe 24 is communicated on the forward end side with a discharge passage 22 via the second valve 23. The end portion of the discharge passage 22, which is disposed on the forward end side, corresponds to the emission port 21 described above. Therefore, when the second valve 23 is in the open state, the drug solution contained in the syringe 24 can be emitted from the emission port 21 via the discharge passage 22. Note that the second valve 23 performs the regulation so that the drug solution flows in only one direction directed from the syringe 24 toward the discharge passage 22. The second valve 23 is normally closed while the valve is pressed in the direction directed to the syringe 24 by means of elastic means such as a spring or the like. Then, the second valve 23 is opened by the force exerted by the flow only when the drug solution flows from the syringe 24 toward the discharge passage 22. However, the opening/closing of the second valve 23 may be also electronically controlled by means of the control device 10.

[0035] In the needleless syringe 20 constructed as described above, the drug solution contained in the vial 5 can be continuously emitted in accordance with the reciprocating motion of the piston 29 in the sliding hole 28 and the opening/closing of the first valve 26 and the second valve 23. The operation for continuously emitting the drug solution will be explained below.

(1) First Operation

[0036] In the first operation, the first valve 26 is closed, the second valve 23 is closed, and the pressurized air is sent from the compressor 2 to the air valve 30. Then, the pressurized air is accumulated to arrive at a predetermined pressure in the valve 30. The predetermined pressure is the pressure at which the piston 29 can be pressurized so that the drug solution can be emitted when the pressurized air is released in accordance with the second operation as described later on. Note that during the first operation, such a state is given that the drug solution is charged into the syringe 24 as a result of the third operation described later on.

(2) Second Operation

[0037] In the second operation, the pressurized air, which is accumulated in the air valve 30, is released for the piston 29 in accordance with the depression of the changeover button 31. As a result, the piston 29 is propelled toward the forward end side in the sliding hole 28 against the urging force received from the positioning spring. Then, the syringe 24 is filled with the drug solution, and hence the drug solution is discharged to the outside of the syringe 24 by being propelled by the piston 29. In this situation, the drug solution flows toward the first valve 26 and the second valve 23. However, the first valve 26 is closed in accordance with the flow of the drug solution, and the drug solution does not flow into the vial 5. Further, the second valve is released in accordance with the flow of the drug solution. The drug solution flows toward the discharge passage 22, and the drug solution is emitted from the emission port 21.

(3) Third Operation

[0038] In the third operation performed after the emission of the drug solution in accordance with the second operation, the changeover button 31 is released from the depression. Accordingly, the pressurized air, which is released in the second operation, is released to the outside of the main syringe body 20a, and the piston 29 is restored to the original position (position shown in FIG. 2), i.e., the position of the piston in the first operation, by means of the positioning spring. Then, the volume of the syringe 24 is restored in accordance with the restoring operation of the piston 29, and the interior of the syringe 24 is in a negative pressure state. Therefore, the urging force is also applied from the elastic means, the second valve 23 is closed, and the first valve 26 is opened. The drug solution, which is accumulated in the vial 5, is sucked into the syringe 24, and the syringe 24 is filled therewith. Then, the first operation and the followings are repeated again after the termination of the third operation. Thus, it is possible to perform the continuous injection by using the needleless syringe 20.

[0039] In this context, with reference to FIG. 1 again, the holding device 40 is arranged at the position of the main passage body 6a opposed to the emission port 21 of the needleless syringe 20 in the injection system 1. The holding device 40 is the device which holds the farmed fish to press the farmed fish against the emission port 21 so that the farmed fish is brought in contact therewith, when the farmed fish is transferred through the transfer space 7 from the first space S1 toward the second space S2. The schematic arrangement of the holding device 40 will be explained on the basis of FIG. 3. The holding device 40 has a main device body 41 which is arranged outside the main passage body 6a, a holding plate 42 which extends along the main passage body 6a, and feet 43. The holding plate 42 is connected with the main device body 41 by the aid of the feet 43, and the holding plate 42 is arranged in the transfer space 7 in the main passage body 6a. Then, the foot 43 is constructed so that the protruding amount from the main device body 41 can be adjusted. When the feet 43 protrude by larger amounts from the main device body 41, then the distance between the holding plate 42 and the emission port 21 is narrowed, and it is possible to hold the farmed fish transferred through the transfer space 7 and press the body thereof against the emission port 21. Note that the protruding amounts of the feet 43 are controlled by the control device 10. Further, a preferred sealing treatment is applied so that no water enters the interior of the main device body 41 when the protruding amounts of the feet 43 are changed. Note that the protrusion and the accommodation of the foot 43 may be performed in accordance with the supply and exclusion of the compressed air from the compressor 2.

[0040] In the injection system 1 shown in FIG. 1, the needleless syringe 20 and the holding device 40 are appropriately controlled by the control device 10, and thus the injection process with the drug solution is executed for the farmed fish which is transferred from the first space S1 to the second space S2. Then, in order to facilitate the transfer of the farmed fish to the second space S2, an inducing device 12 is installed in the first space S1. For example, the inducing device 12 may be constructed as follows. That is, the plurality of farmed fish existing in the first space are excited by applying the stimulation of light, sound or the like thereto. The farmed fish are expelled to the second space via the transfer space 7 that is also the sole space through which the farmed fish can escape from the first space S1. Note that the stimulation of light and/or sound to be applied can be appropriately determined taking the biological characteristics of the farmed fish as the target or object into consideration.

[0041] On the other hand, another method is also available for the inducing device 12. That is, it is also allowable to use such an inducing device that the volume of the first space S1 is gradually decreased, or the spatial shape of the first space S1 is deformed to form a state in which the farmed fish hardly stay in the first space S1 physically. Further, the following arrangement can be also adopted as the inducing device 12. That is, although the size and the spatial shape of the first space S1 itself are not changed, the physical contact is made with the farmed fish, and the farmed fish are expelled to the first space side connecting portion 6b.

[0042] Further, ultrasonic sensors 8a, 8b, which detect the presence of the farmed fish passing through the corresponding transfer space 7 by means of the ultrasonic wave, are installed respectively at the first space side connecting portion 6b and in the vicinity of the connecting portion of the main passage body 6a with respect to the first space side connecting portion 6b. The ultrasonic sensors 8a, 8b are installed while being separated from each other by an appropriate distance so that the respective detection ranges are not overlapped with each other. The ultrasonic sensors 8a, 8b are electrically connected to the control device 10 so that the detection signals of the respective ultrasonic sensors are delivered to the control device 10.

[0043] In the injection system 1 constructed as described above, the injection process shown in FIG. 4 is repeatedly executed by the control device 10. Accordingly, the continuous injection of the drug solution is realized for the farmed fish as described above. The control device 10 is a computer having a memory and a calculating device. The injection process shown in FIG. 4 is executed by executing a predetermined control program.

[0044] At first, in S101, the transfer in the transfer space 7 ranging from the first space side connecting portion 6b to the main passage body 6a is detected for the farmed fish existing in the first space S1 on the basis of the detection signals fed from the ultrasonic sensors 8a, 8b. Specifically, at first, if the presence of any object is detected by the ultrasonic sensor 8b within a predetermined time range from the point in time at which the presence of any object is detected by the ultrasonic sensor 8a disposed near to the first space S1, it is detected that the farmed fish in the first space S1 transfers or moves to the second space via the transfer space 7. Note that the predetermined time range is the time width which is assumed to be required to pass between the two ultrasonic sensors if the farmed fish performs the assumed transfer or movement. Therefore, in this embodiment, if the detection result is obtained by the ultrasonic sensor 8b at a time interval deviated from the predetermined time range, or if the detection is performed by only the ultrasonic sensor 8a, then it is considered that the farmed fish does not transfer toward the second space S2 in the transfer space 7 in this state, and it is unnecessary to perform the injection with the needleless syringe 20. Note that when the transfer of the farmed fish is detected, it is also allowable to judge that the transfer of the farmed fish is detected if any condition other than the detection condition described above is established. Further, in order to perform the correct detection, a device, which detects the passage of the injection target through the transfer space 7 by means of a camera or the like in accordance with the image analysis, can be also used in combination with the ultrasonic sensor. If the process of S101 is terminated, the routine proceeds to S102.

[0045] In S102, the time, at which the objective farmed fish arrives at the injection position for the needleless syringe 20, is calculated on the basis of the detection result obtained in S101. Specifically, when the presence of the farmed fish is detected by the ultrasonic sensors 8a, 8b, the movement speed, which is provided when the farmed fish transfers or moves through the transfer space 7, is calculated from the interval between the respective detection times and the installation distance between the both ultrasonic sensors. Then, the time, which is required until the farmed fish passes in front of the emission port 21 of the needleless syringe 20 after the farmed fish passes in front of the ultrasonic sensor 8b, can be calculated as the arrival time on the basis of the movement speed and the installation position of the needleless syringe 20 (for example, the distance between the ultrasonic sensor 8b and the needleless syringe 20). If the process of S102 is terminated, the routine proceeds to S103.

[0046] In S103, the holding device 40 is started up so that the farmed fish is held by the holding plate 42 to bring the body thereof in contact with the emission port 21 at the point in time at which it is assumed that the farmed fish passes in front of the emission port 21 of the needleless syringe 20 on the basis of the arrival time calculated in S102.

[0047] In S104, the holding device 40 is started up to judge whether or not such a state is given that the farmed fish is held by the holding plate 42. For example, the holding state of the farmed fish can be also judged by detecting the force transmitted via the feet 43 by means of a force sensor (not shown) installed in the main device body 41. Further, in another method, the judgment of the holding state as described above may be replaced with the following procedure. That is, if the protruding amount of the foot 43 is previously determined while considering the assumed size of the farmed fish without utilizing the detecting device such as the force sensor or the like, it is judged whether or not the foot 43 protrudes by a predetermined protruding amount in accordance with the startup of the holding device 40. If the affirmative judgment is made in S104, the process proceeds to S105. If the negative judgment is made, the judgment of S104 is performed again.

[0048] Subsequently, in S105, the injection of the drug solution is executed by the needleless syringe 20 in the state in which the farmed fish as the injection target is held by the holding plate 42 of the holding device 40. The injection of the drug solution is realized in accordance with the first operation and the second operation described above. If the process of S105 is terminated, the routine proceeds to S106. Then, in S106, the charging of the drug solution into the syringe 24 is performed in accordance with the third operation described above after the injection of the drug solution by the needleless syringe 20 is completed in S105.

[0049] As described above, according to the foregoing injection process, when the farmed fish, which is the injection target existing in the first space S1, transfers to the second space S2 via the transfer space 7, then the transfer is detected by the ultrasonic sensors 8a, 8b, and the farmed fish is automatically positioned with respect to the needleless syringe 20. In this positioned state, the emission port 21 is brought in contact with the body of the farmed fish. Therefore, it is possible to preferably realize the injection with the needleless syringe 20 which emits the drug solution by utilizing the pressurized air. Further, the obstructing device 11, which has the inclined plate, is arranged at the second space side connecting portion 6c. Accordingly, it is possible to avoid such a state that the farmed fish, for which the injection has been performed and which has transferred to the second space S2, returns to the first space S1 and it is difficult to manage the injection. Therefore, it is possible to realize the continuous automatic injection of the drug solution with respect to the plurality of farmed fish by repeatedly executing the foregoing injection process by the control device 10. Note that a gate may be arranged at the first space side connecting portion 6b to obstruct the entry of the farmed fish so that the next injection target (farmed fish) does not enter the transfer passage 6 until the injection with the needleless syringe 20 is completed. The gate may be opened/closed by the control device 10. For example, the gate may be once closed after the passage is detected by the ultrasonic sensor 8a, and the gate may be opened again when the injection is completed (when the holding device 40 is released).

First Modified Embodiment

[0050] In the injection system 1 shown in FIGS. 1 to 3, the emission port 21 of the needleless syringe 20 and the holding plate 42 of the holding device 40 are arranged so that they are opposed to one another at the main passage body 6a. In the case of this arrangement, the body of the farmed fish is pressed against the emission port 21 by the holding plate 42. On the other hand, as a modified embodiment thereof, it is also allowable that the needleless syringe 20 and the holding device 40 are constructed integrally so that the emission port 21 of the needleless syringe 20 is open on the holding plate 42. In this case, the emission port 21 is brought in contact with the body of the farmed fish together with the holding plate 42, and then the farmed fish is pressed against the inner wall of the opposing main passage body 6a. Even in the case of the embodiment as described above, when the injection by the needleless syringe 20 is executed, such a state is given that the emission port 21 is brought in contact with the body of the farmed fish. Therefore, it is possible to realize the preferred emission of the drug solution.

Second Modified Embodiment

[0051] In the case of the needleless syringe 20 used in the embodiment described above, the release energy based on the pressurized air is utilized for the propelling force of the piston 29. In place of this mode, it is also allowable that a syringe, which carries a plurality of igniters or exploders that carry a propellant and which realizes the continuous emission of the drug solution by successively starting up the plurality of igniters, is adopted as the needleless syringe 20. In this case, the igniter and the piston 29 are arranged so that the combustion product, which is produced by the combustion of the propellant in the igniter, pressurizes the piston 29. Further, a gas producing agent or the like, which is combusted by the combustion product and which produces the gas, can be further arranged between each of the igniters and the piston 29 as well. The gas producing agent is exemplified, for example, by a single base smokeless propellant (gunpowder) composed of 98% by mass of nitrocellulose, 0.8% by mass of diphenylamine, and 1.2% by mass of potassium sulfate. Further, it is also possible to use various gas producing agents used for a gas generator (gas producer) for the air bag and a gas generator (gas producer) for the seat belt pretensioner.

[0052] Note that the igniter powder, which is usable in the igniter, is preferably exemplified by a propellant containing zirconium and potassium perchlorate (ZPP), a propellant containing titanium hydride and potassium perchlorate (THPP), a propellant containing titanium and potassium perchlorate (TiPP), a propellant containing aluminum and potassium perchlorate (APP), a propellant containing aluminum and bismuth oxide (ABO), a propellant containing aluminum and molybdenum oxide (AMO), a propellant containing aluminum and copper oxide (ACO), a propellant containing aluminum and iron oxide (AFO), and propellants composed of combinations of a plurality of the propellants described above. The propellants as described above have the following characteristics. That is, the plasma at a high temperature and a high pressure is generated during the combustion immediately after the ignition. However, when the temperature becomes the ordinary temperature, and the combustion product is condensed, then the generated pressure is suddenly lowered, because no gas component is contained. It is also allowable that any propellant other than the above is used as the igniter powder, provided that the appropriate injection can be performed.

Third Modified Embodiment

[0053] The injection system 1 concerning the embodiment described above realizes the injection of the drug solution with respect to the farmed fish existing in water. However, in place of this mode, it is also possible to make the application to any domestic animal (for example, cattle and pig) existing on land. In this case, no water exists between the needleless syringe 20 and the domestic animal. Therefore, on condition that the emission speed of the drug solution emitted from the needleless syringe 20 is sufficiently high, the drug solution can be injected without causing any trouble in some cases, even when the emission port 21 and the body of the domestic animal are somewhat separated from each other. In such a situation, it is not necessarily indispensable to provide the holding device 40 shown in FIGS. 1 and 3. Of course, it is also allowable to install the holding device 40 for the injection system 1 in order to perform the injection of the drug solution more stably.

DESCRIPTION OF THE REFERENCE SIGNS

[0054] 1: injection system, 2: pressurized air supply apparatus (compressor), 4: solenoid startup device, 5: vial, 6: transfer passage, 7: transfer space, 8a, 8b: ultrasonic sensor, 10: control device, 11: obstructing device, 12: inducing device, 20: needleless syringe, 21: emission port, 22: discharge passage, 23: second valve, 24: syringe, 25: drug solution supply passage, 26: first valve, 28: sliding hole, 29: piston, 30: air valve, 31: changeover button, 40: holding device, 42: holding plate.