JP7012728B2 - Injector - Google Patents

Description

The present invention relates to an injector that injects a target substance into a target area of an object.

In a syringe, regardless of the presence or absence of an injection needle, the injection solution can be ejected by pressurizing the injection solution. For example, in a needleless syringe that injects without a needle, the injection solution is realized. Explosives may be used as a pressurizing source (see, eg, Patent Document 1). The needleless syringe shown in Patent Document 1 is provided with a detonator and a fire extinguisher, and when a detonator pierces the detonator and the detonator ignites, the heat energy is transmitted to the fire extinguisher. Then, the fireworks charge is burned there, and the injection liquid is pressurized. As such an explosive, a single explosive based on nitrocellulose is used.

In addition, the combustion energy of explosives is used as a power source for pressurization even in a field different from that of a syringe. For example, Patent Document 2 discloses a technique relating to an actuator for driving a control member through a membrane using the combustion energy of explosives and blocking the flow of a medium in a flow path. In this technology, the elastically deformable membrane sandwiched between the control member and the housing is deformed by receiving the combustion pressure of the explosive, and the cylinder portion attached to the membrane is displaced to drive the control member. It is a thing.

Japanese Patent Publication No. 2004-532049 U.S. Pat. No. 6,397,595

When the combustion energy of explosives is used as a power source for pressurization, it is necessary to consider the influence of combustion products such as combustion gas and combustion residue produced by the combustion. For example, when an explosive is used as a pressurizing source of an injection solution in a syringe, it is not preferable from the viewpoint of hygiene that the combustion product is mixed with a target substance such as an injection solution to be pressurized.

On the other hand, it is a membrane that can be elastically deformed as in the prior art, and it distinguishes between the space where the explosives are burned and the space where the object to be pressurized is placed, and the combustion energy of the explosives is transferred through the deformation of the membrane. When it is transmitted to the object to be pressurized, the film is rapidly elastically deformed during combustion. Then, in order to displace the object to be pressurized by the required distance by pressurization, it is necessary to secure the amount of deformation of the film according to the required distance in the deformation. Therefore, in the prior art, it is necessary for the membrane to be greatly elastically deformed toward the control member due to the combustion of the explosive, and there is a concern that the membrane may be damaged or cleaved in some cases. If the membrane is damaged or the like, it becomes difficult to seal the combustion product in the space on the side where combustion is performed. In addition, the presence of the membrane may hinder the sufficient transfer of combustion energy to the control member.

Therefore, in view of the above-mentioned problems, the present invention suppresses the action of the combustion product produced by the combustion of the explosive on the target substance in the injector that injects the target substance by the combustion of the explosive, and at the same time, obtains the energy for the injection. The purpose is to preferably convey to the target substance.

In order to solve the above problems, in the present invention, the sealing member that divides the space inside the injector body into the ignition device side and the first piston portion side ignites the combustion product produced by the ignition device. We adopted a configuration that seals in the space on the device side. With such a configuration, it is possible to prevent the combustion product from being mixed with the target substance. Further, the fixing force of the sealing member is made larger than the sliding force, and the contact portion of the sealing member with the first piston portion is burned by the ignition device to the fixed end portion of the sealing member. On the other hand, we adopted a configuration that moves from the starting position on the ignition device side to the injection position on the syringe section side. With such a configuration, the sealing member is less likely to be torn while the moving amount of the first piston portion is suitably secured.

Specifically, the present invention is an injector that injects a target substance into a target region, and is slidably arranged in an injector main body having a through hole formed in the axial direction and in the through hole. A first piston portion, a syringe portion arranged on the distal end side of the injector body, a storage chamber capable of accommodating the target substance, and the purpose of the accommodation chamber as the first piston portion slides. A plunger that pressurizes the substance, a nozzle portion that includes a flow path through which the target substance in the containment chamber pressurized by the plunger flows, and a nozzle portion that ejects the target substance from an injection port formed at the tip of the flow path. A syringe unit having The space inside the injector main body is divided into a first space in which the ignition device is arranged and a second space in which the first piston portion is arranged, and the combustion product produced by the ignition device is obtained. A sealing member for sealing in the first space is provided. Further, the first piston portion has a plunger side end portion that comes into contact with the plunger and a predetermined end portion having a predetermined end surface that receives the injection energy, and the sealing member is the injector main body. It has a fixed end portion fixed to an inner wall defining an inner space, and a contact portion that comes into contact with the predetermined end surface of the predetermined end portion when burning explosives in the ignition device, and the fixed end portion with respect to the inner wall. The fixing force of the first piston portion is configured to be larger than the sliding force of the first piston portion in the through hole. Further, in the state before the explosive combustion in the ignition device, the contact portion is located at the starting position on the ignition device side with respect to the fixed end portion, and the contact portion is caused by the explosive combustion in the ignition device. It is configured to come into contact with the predetermined end surface and move to the injection position on the syringe portion side with respect to the fixed end portion while sliding the first piston portion.

In the injector according to the present invention, the contact portion of the sealing member moves from the starting position to the injection position due to the injection energy generated by the combustion of the explosive in the ignition device, and in the process of the movement, the predetermined end face of the first piston portion. The first piston portion slides in the through hole. Then, pressure is applied to the target substance contained in the storage chamber of the syringe portion via the plunger by sliding the first piston portion, so that the target substance is ejected from the injection port to the outside of the injector. .. If the movement of the contact portion in the sealing member is caused by the combustion of the explosive, the configuration is such that the injection energy acts directly on the first piston portion via the contact portion, or the injection energy is once applied to another gas. , A configuration in which the gas is propagated to a liquid, a solid, or the like and then indirectly acts on the first piston portion via the contact portion, or the like can be appropriately adopted.

In addition, the target substance contains components that are expected to be effective inside the target area, and if injection by injection energy is possible, the state of the target substance contained in the injector, liquid, gel, etc. The specific physical form of the target substance such as a fluid, powder, or granular solid does not matter. Then, the target substance contains a component to be sent to the target region of the living body which is the target substance, and the component may exist in a state of being dissolved inside the target substance, or the component is simply not dissolved and is not dissolved. It may be in a mixed state. For example, there are vaccines for antibody enhancement, proteins for beauty, cultured cells for hair regeneration, etc. as components to be sent, and these are made into fluids such as liquids and gels so that they can be ejected. The target substance is formed by being contained. Further, the injector may also be a type that supplies the target substance to the target region via a needle, or may be a type that supplies the target substance without a needle.

Here, in the injector according to the present invention, the igniter for burning the explosive is one in which the igniter contained in the igniter is ignited by the execution of the igniter to generate the combustion product of the igniter. It may be present, or the ignition of the igniting agent further burns a known gas generating agent (for example, a single-based smokeless explosive) to produce the igniting agent and the combustion product of the gas generating agent. Also, the injector of the present invention does not limit the specific configuration of the ignition device.

When the explosive is burned in such an ignition device, the combustion product diffuses into the space inside the injector body, and generally transfers the injection energy to the first piston portion via pressure, heat, etc. Is the power source for the injection of the target substance as described above. Here, since the injector according to the present invention is provided with a sealing portion, the combustion product is sealed in the first space and does not enter the second space. Therefore, it is possible to suppress the unfavorable action of the combustion product on the target substance. Then, in order to obtain the sealing effect, the sealing member needs to have a certain degree of resistance to the combustion of the explosive, and on the other hand, by providing the sealing member, the first piston portion of the injection energy is provided. It is not desirable that the transmission of energy is inhibited. Therefore, the sealing member needs to have both a suitable sealing of the combustion product and a suitable transfer of the injection energy to the first piston portion.

Therefore, in the sealing member, the fixing force of the fixed end portion is set to be larger than the sliding force of the first piston portion in the through hole. As a result, the sealing member that affects the sealing effect in the first space can be suitably fixed to the inner wall of the injector body, so that the first piston portion is slid through the through hole when assembling the injector. By moving it, it is possible to stably form a state in which the contact portion with the sealing member, that is, a state in which the predetermined end surface of the first piston portion is in contact with the contact portion of the sealing member. Such a stable contact state between the first piston portion and the sealing member is an important factor for suitable transmission of injection energy to the first piston portion.

Further, in the sealing member, the contact portion is located at the injection position on the syringe portion side from the starting position on the ignition device side with respect to the fixed end portion where the contact portion is fixed to the inner wall of the space inside the injector body. It is configured to move in contact with a predetermined end face of the. With such a configuration, after the explosive is burned, the sealing member is deformed so that the contact portion is turned inside out with respect to the fixed end portion, and the sliding of the first piston portion is promoted. Therefore, unlike the prior art, the sealing member is not greatly stretched in only one direction when the explosive is burned, and the sealing member is less likely to be damaged. Further, when the above-mentioned inverted structure is adopted, the moving range of the contact portion becomes from the starting position on the ignition device side to the injection position on the syringe portion side with respect to the fixed end portion when the first piston portion slides. While ensuring the amount of movement of the contact portion corresponding to the sliding distance of the first piston portion for injecting a substance, the sealing member does not need to be significantly deformed, and thus the injection energy is transmitted by the sealing member. Is less likely to be disturbed. This contributes to both the suitable sealing of the combustion product and the suitable transfer of the injection energy to the first piston portion.

Further, in the above injector, the syringe portion is configured to be attachable to the injector main body, and when the syringe portion is attached to the injector main body, the first piston portion is attached to the plunger. A contact state of contact may be formed. In that case, even if the fixing force of the fixed end portion to the inner wall is further set to be larger than the force for pushing the target substance contained in the storage chamber toward the nozzle portion by the plunger. good. With such a configuration, even if the sealing member receives a force from the plunger when attaching the syringe portion, the sealing member can be suitably prevented from being damaged, and thus the injection to the first piston portion can be performed. Suitable transfer of energy can be achieved.

Further, in the above injector, the first piston portion may be configured to be able to be pushed into the through hole from the plunger side end portion side before the syringe portion is attached to the injector main body. With such a configuration, the contact state between the first piston portion and the sealing member can be suitably formed before the explosive combustion by the ignition device. The pushing of the first piston portion may be performed not only from the end portion on the plunger side but also by other means capable of displace the first piston portion.

Further, in the injector according to the present invention, the sealing member may be formed of an elastic member. As a result, the sealing member is stretched during the combustion of the explosive in the igniter, so that it is possible to more preferably achieve both the sealing of the combustion product and the transmission of the injection energy to the first piston portion.

Further, the sealing member covers the side surface portion of the predetermined end portion along the sliding direction of the first piston portion in the state before the explosive combustion in the ignition device, and the fixed end portion and the contact portion. An intermediate portion formed between the two may be provided, in which case the intermediate portion extends in the sliding direction as the first piston portion slides due to the combustion of explosives in the ignition device. , The contact portion is configured to move from the starting position to the ejection position. In the injector configured in this way, the contact portion moves while the intermediate portion of the sealing member extends in the sliding direction of the first piston portion, and the first piston portion is propelled. The piston portion is provided with a sliding amount corresponding to the extension. Due to such an action, the injection energy from the combustion of the explosive is suitably used for propelling the first piston portion, and the sliding amount of the first piston portion that pressurizes the target substance is suitably secured. Is possible. Further, since the intermediate portion extending in the sliding direction of the first piston portion is formed by the elastic member, the intermediate portion can be flexibly extended, and as a result, the sealing member is less likely to be damaged.

In the injector, the outer diameter of the first piston portion at the predetermined end portion may be smaller than the inner diameter of the through hole. In that case, with the sliding of the first piston portion due to the combustion of gunpowder in the ignition device, the intermediate portion extends in the sliding direction along the inner wall surface of the through hole. According to such a configuration, the first piston portion has a radial gap with respect to the through hole in the vicinity of the predetermined end portion. Then, when the contact portion moves due to the combustion of the explosive, the intermediate portion can be extended by utilizing the gap, so that the extension of the intermediate portion can be easily performed smoothly. As a result, it is possible to suitably secure the sliding amount of the first piston portion that pressurizes the target substance, and it is possible to avoid damage to the sealing member.

Further, in the injectors described above, the second piston portion that is more slidable in the through hole and is arranged on the first space side, and the contact portion of the sealing member is the first. A second piston portion arranged so as to be sandwiched with the predetermined end surface of the piston portion may be further provided. In that case, the second piston portion faces the ignition device and is input to the ignition device side end portion, and the injection energy is transmitted to the predetermined end surface of the first piston portion via the contact portion. It has a first piston portion side end portion to be transmitted.

In the injector configured in this way, the injection energy from the ignition device is received by the ignition device side end portion of the second piston portion, and the first piston is received by the first piston portion side end portion which is the other end portion. Injection energy is transmitted to a predetermined end surface of the first piston portion via the contact portion of the sealing member sandwiched between the portion and the second piston portion. Therefore, the sealing member does not directly receive the injection energy from the ignition device, but receives it through the second piston member. As a result, during the combustion of the explosive, the contact portion is not directly exposed to the combustion product of high temperature and high pressure, and thus the sealing member including the contact portion can be more reliably prevented from being damaged. Further, since the contact portion is sandwiched between the first piston portion and the second piston portion, a force for turning over the sealing member as described above can be appropriately applied to the sealing member, and thus the sealing member can be smoothly applied. The sliding of the first piston portion can be expected.

According to the present invention, in an injector that injects a target substance by combustion of explosives, the action of combustion products produced by combustion of explosives on the target substance is suppressed, and energy for injection is suitably transmitted to the target substance. It becomes possible.

It is a figure which shows the schematic structure of the injector which concerns on 1st Embodiment of this invention. It is a figure which shows the detail of the piston of the injector shown in FIG. It is a figure which shows the schematic structure of the initiator (ignition device) mounted on the injector shown in FIG. 1. FIG. 1 is a first diagram showing a flow of assembling the injector shown in FIG. 1. FIG. 2 is a second diagram showing a flow of assembling the injector shown in FIG. In the injector shown in FIG. 1, it is a figure which compares the state before combustion of the explosive in the initiator and the state after combustion. It is a figure which shows the schematic structure of the injector which concerns on 2nd Embodiment of this invention.

Hereinafter, as an injector according to the embodiment of the present invention with reference to the drawings, a needleless injector 1 (hereinafter, simply referred to as “injector 1”) will be described as an example. The configurations of the following embodiments are examples, and the present invention is not limited to the configurations of these embodiments.

<First Embodiment>
FIG. 1A is a cross-sectional view of the injector 1, and FIG. 1B is a view of the injector 1 as viewed from the nozzle portion 9 side for injecting the injection liquid. In the following description of the present application, the target substance injected into the target area of the object by the injector 1 is collectively referred to as “injection liquid”. However, this has no intention of limiting the content or form of the injected substance. In the target substance, the component to be delivered to the skin structure may or may not be dissolved, and the target substance may also be one that can be ejected from the nozzle portion 9 to the skin structure by pressurization. For example, the specific form thereof does not matter, and various forms such as liquid, gel, and powder can be adopted.

Here, the injector 1 has an injector main body 2 composed of a first housing 3 and a second housing 4, and the tip side of the injector main body 2 (the first housing 3 of the second housing 4). The syringe portion 5 is arranged on the end portion side opposite to the end portion connected to the syringe portion 5. The first housing 3 and the second housing 4 are fixed with screws and integrated. Here, a combustion chamber 31, which is an internal space extending in the axial direction thereof, is formed inside the first housing 3, and similarly, in the axial direction thereof, inside the second housing 4. A through hole 37, which is an extending internal space, is formed. Although the combustion chamber 31 and the through hole 37 are separated by a sealing member 8 described later, they are internal spaces that are continuously arranged inside the injector main body 2.

Further, as shown in FIG. 2, a mounting space 4c to which the syringe portion 5 is attached is formed on the injector tip side (the side on which the syringe portion 5 is arranged) of the second housing 4. Further, a screw thread for screwing and mounting with the syringe portion 5 is formed on the inner wall surface of the side wall 4d forming the mounting space 4c, and the syringe portion 5 is formed by the screw thread until it hits the bottom surface 4b of the mounting space 4c. 2 Screwed into the housing 4.

Further, the syringe portion 5 provided on the tip end side of the injector main body 2 includes a syringe portion main body 11 having a storage chamber 33 for accommodating the injection liquid ML inside, and a nozzle portion 9 in which a flow path through which the injection liquid flows is formed. And has a nozzle holder 10 provided with a nozzle portion 9. The nozzle holder 10 is attached to the syringe portion main body 11 by the holder cap 12 with the gasket 13 interposed therebetween. Further, by screwing the syringe portion main body 11 into the thread of the side wall 4d of the second housing 4 of the injector main body 2, the syringe portion 5 and the second housing 4 are attached, and in the attached state, the syringe portion 5 and the second housing 4 are attached. 2 The through hole 37 in the housing 4 and the storage chamber 33 in the syringe portion main body 11 form a continuous space. In the mounted state, the injection liquid ML is liquid-tightly housed in the storage chamber 33 by the plunger 7, and the plunger 7 is exposed on the through hole 37 side. Here, the plunger 7 is slidably arranged in the accommodation chamber 33, and further, by sliding, the injection liquid ML is pressurized, and the injection liquid is ejected from the nozzle portion 9. Further, the plunger 7 is formed of a rubber member having a surface coated with a thin layer of silicone oil so that the plunger 7 can smoothly slide in the accommodation chamber 33.

Next, a metal piston 6 is arranged in the through hole 37 in the second housing 4 of the injector main body 2, and the piston 6 is slidably held in the through hole 37. Here, the details of the piston 6 are shown in FIG. 2 so that the positional relationship with the second housing 4 can be grasped. The piston 6 is formed in a substantially axial shape extending along the axial direction of the through hole 37, and has an end portion on the combustion chamber 31 side (hereinafter referred to as “first end portion”) 6a and an end on the syringe portion 5 side. It has a portion, that is, an end portion (hereinafter referred to as "second end portion") 6b that contacts the plunger 7 arranged in the syringe portion 5, and the piston 6 can smoothly slide in the through hole 37. An O-ring 6c is arranged around the piston 6. Here, the first housing 3 (indicated by a dotted line in FIG. 2) and the second housing 4 are attached to form the injector main body 2, and before the explosive combustion is performed by the initiator 20 which is the ignition device described later. In the state (hereinafter referred to as “pre-ignition state”), the first end portion 6a is from the end surface of the fitting portion 4a of the second housing 4 fitted in the combustion chamber 31 of the first housing 3 to the combustion chamber. It is in a state of substantially protruding to the 31 side. Further, the diameter d1 of the first end portion 6a is smaller than the diameter d0 of the through hole 37. Therefore, when the piston 6 slides in the through hole 37 toward the syringe portion 5, it is constant between the side surface of the first end portion 6a (the surface along the axial direction of the piston 6) and the inner wall surface of the through hole 37. A gap will be formed.

Here, in the pre-ignition state shown in FIG. 1, the sealing member 8 is fixed on the end surface of the fitting portion 4a of the second housing 4, which is a part of the inner wall of the injector main body 2, and the sealing member 8 is fixed. , A space including a combustion chamber 31 located on the initiator 20 side (corresponding to the first space according to the present invention) and a through hole 37 located on the piston 6 side in the space inside the injector main body 2 which is formed of an elastic material. It is divided into a space including (corresponding to the second space according to the present invention), whereby the combustion product produced by the combustion of the explosive in the initiator 20 is sealed in the combustion chamber 31. There is. The details of the structure of the sealing member 8 and the operation by burning the explosive in the initiator 20 will be described later.

Here, an example of the initiator 20 will be described with reference to FIG. The initiator 20 is an electric ignition device, and a space for arranging the igniter 22 is defined in the cup 21 by a cup 21 whose surface is covered with an insulating cover. A metal header 24 is arranged in the space, and a cylindrical charge holder 23 is provided on the upper surface thereof. The igniter 22 is held by the charge holder 23. A bridge wire 26 that electrically connects one of the conductive pins 28 and the metal header 24 is wired to the bottom of the igniter 22. The two conductive pins 28 are fixed to the metal header 24 via an insulator 25 so that they are insulated from each other when a non-voltage is applied. Further, the opening of the cup 21 extending from the two conductive pins 28 supported by the insulator 25 is protected by the resin collar 27 in a state where the insulation between the conductive pins 28 is well maintained.

In the initiator 20 configured in this way, when a voltage is applied between the two conductive pins 28 by an external power source, a current flows through the bridge wire 26, whereby the igniter 22 burns. At this time, the combustion product from the combustion of the igniter 22 is ejected from the opening of the charge holder 23. Further, the initiator cap 14 has a brim-shaped cross section so as to be hooked on the outer surface of the initiator 20, and is screw-fixed to the first housing 3. As a result, the initiator 20 is fixed to the first housing 3 by the initiator cap 14, and thus the initiator 20 itself can be prevented from falling off from the injector main body 2 due to the pressure generated at the time of ignition by the initiator 20.

Here, as the igniting agent 22 used in the injector 1, preferably, an explosive containing zirconium and potassium perchlorate (ZPP), an explosive containing titanium hydride and potassium perchlorate (THPP), titanium and perchloric acid. Gunpowder containing potassium (TiPP), gunpowder containing aluminum and potassium perchlorate (APP), gunpowder containing aluminum and bismuth oxide (ABO), gunpowder containing aluminum and molybdenum oxide (AMO), gunpowder containing aluminum and copper oxide. (ACO), explosives containing aluminum and iron oxide (AFO), or explosives consisting of a plurality of combinations of these explosives can be mentioned. These explosives generate high-temperature and high-pressure plasma during combustion immediately after ignition, but when they reach room temperature and condense combustible organisms, they do not contain gas components, so the generated pressure drops sharply. In addition, explosives other than these may be used as ignition agents.

Here, although nothing is arranged in the combustion chamber 31 shown in FIG. 1, a gas generating agent that burns by the combustion product generated by the combustion of the igniter 22 and generates gas is arranged in the combustion chamber 31. You may do so. If a gas generating agent is arranged in the combustion chamber 31, an example thereof is a single-based smokeless powder composed of 98% by mass of nitrocellulose, 0.8% by mass of diphenylamine, and 1.2% by mass of potassium sulfate. It is also possible to use various gas generators used in gas generators for airbags and gas generators for seatbelt pretensioners. Unlike the case where only the igniter 22 is used in combination with such a gas generating agent, the predetermined gas generated at the time of combustion contains a gas component even at room temperature, so that the rate of decrease in the generated pressure is small. Further, although the combustion completion time of the gas generating agent at the time of combustion is extremely longer than that of the igniting agent 22, the size, size, and shape of the gas generating agent when arranged in the combustion chamber 31, particularly the surface. By adjusting the shape, it is possible to change the combustion completion time of the gas generating agent. By adjusting the amount, shape, and arrangement of the gas generating agent in this way, the generated pressure in the combustion chamber 31 can be appropriately adjusted.

A plurality of nozzle portions 9 may be formed on the nozzle holder 10, or one may be formed. When a plurality of nozzle portions are formed, a flow path corresponding to each nozzle portion is formed so that the injected liquid ML released to each nozzle is fed as evenly as possible. Further, when a plurality of nozzle portions 9 are formed, it is preferable that the nozzle portions are arranged at equal intervals around the central axis of the injector 1 as shown in FIG. 1 (c). Further, the flow path diameter of the nozzle portion 9 is configured to be smaller than the inner diameter of the through hole 37. Thereby, the injection pressure of the injection liquid at the time of injection can be suitably increased.

Here, the details of the sealing member 8 in the pre-ignition state will be described. As shown in FIG. 1, the sealing member 8 is formed so as to cover the first end portion 6a of the piston 6 which is arranged so as to protrude toward the combustion chamber 31 side. Specifically, the sealing member 8 is a contact portion located so as to contact the fixed end portion 35 fixed on the fitting portion 4a of the second housing 4 and the end surface of the first end portion 6a and cover the end surface. It has an intermediate portion 36 formed between the contact portion 34 and the fixed end portion 35 and located so as to cover the side surface portion of the first end portion 6a. Therefore, as shown in FIG. 1, in the cross section along the axial direction of the injector 1, the sealing member 8 is formed in a U shape, and the contact portion 34 corresponding to the bottom surface thereof is relative to the fixed end portion 35. It will be located at the starting position on the initiator 20 side (on the left side when facing FIG. 1).

Further, as described above, the sealing member 8 formed of the elastic member is fixed on the end surface of the fitting portion 4a of the second housing 4, and the end portion of the fixed sealing member 8 is fixed to the fixed end portion 35. Become. The fixing force at the fixed end portion 35 is determined so that the fixing force of the fixed end portion 35 with respect to the end surface of the fitting portion 4a is larger than the sliding force of the piston 6 at the through hole 37. The fixing force is fixed to resist the external force that separates the sealing member 8 from the second housing 4 in the combustion chamber 31 corresponding to the first space within the range in which the sealing performance of the combustion product is maintained. It is a coupling force between the end portion 35 and the fitting portion 4a. An example of the external force to be disengaged is a pressing force in which the piston 6 pushes the sealing member 8. Further, the sliding force is a force applied to the piston 6 along the sliding direction in order to slide the piston 6 in the through hole 37. As described above, since the O-ring 6c is arranged on the piston 6, the force that opposes the frictional force generated between the piston 6 and the through hole 37 via the O-ring 6c is generally the sliding force. If there is an element that causes frictional force other than the O-ring, the sliding force is certified in consideration of the frictional force due to that element.

Here, regarding the setting of the fixing force at the fixed end portion 35, for example, the sealing member 8 is sufficiently stable with respect to the force received from the piston 6 so that the fixing of the fitting portion 4a to the end surface is maintained. A fixing force obtained by multiplying the assumed sliding force of the piston 6 by a predetermined safety factor λ may be generated at the fixed end portion 35. The predetermined safety factor λ may be set to, for example, 10. For example, in the two cases shown in Table 1 below (φ5.8 mm in case 1 and φ8.8 mm in case 2) in which the diameters of the pistons 6 are different, the measurement experiment of the sliding force of the pistons 6 was performed three times, and the average thereof. The value is used as the reference sliding force in each case (0.28 kgf in case 1 and 0.51 kgf in case 2). Then, the force calculated by multiplying the standard sliding force by 10 times the safety factor is defined as the fixing force at the fixed end portion 35 corresponding to each case (2.8 kgf in case 1 and 5.1 kgf in case 2). The fixed end portion 35 and the end face of the fitting portion 4a are fixed so that the fixing force is realized.

Next, a method of assembling the injector 1 will be described with reference to FIGS. 4A and 4B. 4A and 4B show the flow in which the injector 1 is assembled in the order of steps 1 to 6.
(Step 1)
The fixed end portion 35 of the sealing member 8 is fixed to the end surface of the fitting portion 4a of the second housing 4 with an adhesive. The type of adhesive, the adhesive conditions, and the like are adjusted so that the fixing force of the adhesive is equal to or greater than the value obtained by multiplying the sliding force of the piston 6 by the predetermined safety factor λ as described above. In the state immediately after the fixed end portion 35 is fixed to the end surface of the fitting portion 4a, the piston 6 has not yet been inserted into the second housing 4, and the first end portion 6a of the piston 6 and the sealing member 8 have not been inserted. It is not in contact with the contact portion 34 of.
(Step 2)
In the next step, the piston 6 is inserted into the through hole 37 of the second housing 4 from the mounting space 4c side with the first end portion 6a as the head, and the sealing member 8 having a U-shape is formed. The first end portion 6a is fitted into the recess (the recess formed by the intermediate portion 36 and the contact portion 34). Since the diameter of the concave portion formed by the intermediate portion 36 is slightly larger than the diameter of the first end portion 6a, the force applied to the piston 6 when pushing the piston 6 is approximately the frictional force between the piston 6 and the through hole 37. That is, it becomes a sliding force.

(Step 3)
Then, as the pushing of the piston 6 progresses, the first end portion 6a comes into contact with the contact portion 34. At this time, as described above, the fixing force at the fixed end portion 35 of the sealing member 8 is set to 10 times the sliding force of the piston 6, so that the reaction force from the piston 6 suddenly increases at the same time as the contact. Therefore, it is possible to accurately and promptly recognize that the contact state between the first end portion 6a and the contact portion 34 is formed by the pushing operation. This means that by pushing the piston 6 too much, an excessive force is applied from the piston 6 to the sealing member 8 so that the sealing member 8 can be properly fixed (that is, the combustion chamber 31 can be sealed with the combustion product). It is possible to avoid damaging the necessary fixed state). In particular, since the inside of the sealing member 8 cannot be seen from the outside, suddenly changing the force for pushing the piston 6 when the contact state is formed is a suitable contact state between the contact portion 34 and the first end portion 6a. It is extremely useful for securing. It should be noted that such a suitable contact state between the contact portion 34 and the first end portion 6a is an extremely important factor for ensuring the injection of the injection liquid by the injector 1 as described later. When the contact portion 34 and the first end portion 6a are in contact with each other, the end surface of the second end portion 6b of the piston 6 is flush with the bottom surface 4b or is located in the through hole 37 from the bottom surface 4b. Is held in.

(Step 4)
Then, after the contact portion 34 and the first end portion 6a are brought into contact with each other, the second housing 4 is screwed into the first housing 3. At this time, the fitting portion 4a of the second housing 4 enters the inside of the first housing 3. As a result, the combustion chamber 31 is formed by the sealing member 8 inside the first housing 3.

(Step 5)
Then, in step 5, the syringe portion 5 is screwed into the second housing 4. In the state before the syringe portion 5 is attached to the second housing 4 (the state shown in FIG. 4B), the second end portion 6b of the piston 6 is held at a position closer to the inside of the through hole 37 than the bottom surface 4b. On the other hand, the end portion of the plunger 7 of the syringe portion 5 (the end portion not in contact with the injection liquid ML) is in a state of slightly protruding outward from the end surface of the syringe portion main body 11. As a result, when the syringe portion 5 is screwed and attached to the second housing 4, the plunger 7 is in contact with the second end portion 6b of the piston 6 arranged in the second housing 4 ( See step 6). Since the fixing force at the fixed end portion 35 of the sealing member 8 is set to be larger than the force that can push out the injection liquid ML stored in the storage chamber 33 by the plunger 7, the plunger 7 is assumed to be screwed. However, even if the piston 6 can interfere with the piston 6, the injection liquid ML is likely to be discharged as a result, and it is possible to prevent the sealing member 8 from being damaged due to an excessive force.

In the assembly method shown in FIGS. 4A and 4B, the piston 6 is pushed into the second housing 4 to fit the first end portion 6a into the recess of the sealing member 8, and the first end portion 6a and the contact portion 34 are connected to each other. After the contact, the first housing 3 and the second housing 4 are screwed together, but the assembly may be performed as follows instead of the mode. That is, with the sealing member 8 attached in step 1, the second housing 4 is screwed into the first housing 3 (see step 4). After that, as in step 2, the piston 6 is inserted into the second housing 4, the first end portion 6a is fitted into the recess of the sealing member 8, and the first end portion 6a is brought into contact with the contact portion 34 of the sealing member 8. (See step 3). Even according to such an assembly flow, as described above, the reaction force from the piston 6 suddenly increases at the same time as the contact between the first end portion 6a and the contact portion 34, so that the contact state is accurately formed. Can be recognized quickly and quickly.

Further, in another aspect, the sealing member 8 is first attached to the first housing 3, that is, the sealing member 8 is fixed to the first housing 3 via the fixed end portion 35, and then the piston 6 is inside. The arranged second housing 4 may be screwed into the first housing 3. In this case, the dimensions and shape of the piston 6 and the second housing 4 are adjusted so that the contact state between the contact portion 34 and the first end portion 6a is formed, and the sealing member 8 is appropriately fixed. In addition, an appropriate configuration such as a fitting groove for joining the fixed end portion 35 may be formed on the inner wall of the first housing 3.

Here, the movement of the sealing member 8 when the igniter 22 of the initiator 20 burns, and the injection state of the injection liquid in the injector 1 will be described with reference to FIG. FIG. 5 shows the configuration of the injector 1 in the pre-ignition state in the upper row, and in the lower row, the injector 1 in a state where the injection of the injection liquid is completed by the combustion of the ignition charge 22 (hereinafter referred to as “injection completed state”). The configuration is shown. In the comparison between the pre-ignition state and the injection completion state in FIG. 5, the positions of the fixed end portions 35 of the sealing member 8 are aligned, and both states are displayed side by side in the axial direction of the injector 1. The position of the fixed end portion 35 common to both states is displayed as X0, and the reference line including the position X0 is displayed as L0.

Further, in the pre-combustion state, the position of the contact portion 34 is indicated by X1, and is the position on the initiator 20 side with respect to the position X0 as described above. Further, the position of the plunger 7 at this time is indicated by P1. Here, when the igniter 22 burns, the combustion product diffuses into the combustion chamber 31, and the pressure in the combustion chamber 31 rises. As a result, the pressure is also applied to the sealing member 8, but in particular, the pressure for pressing the piston 6 toward the syringe portion 5 is the pressure applied to the piston 6 via the contact portion 34 of the sealing member 8. Is. Therefore, the end face of the first end portion 6a of the piston 6 with which the contact portion 34 comes into contact becomes the end face that receives the injection energy from the initiator 20.

As described above, the contact portion 34 is a portion of the sealing member 8 that transmits the injection energy generated by the combustion of the ignition charge 22 to the piston 6 side. As a result, in the sealing member 8, the contact portion 34 moves toward the syringe portion 5, and the piston 6 slides in the through hole 37. Then, as the piston 6 slides, the plunger 7 presses the injection liquid ML, and as a result, the injection liquid ML is ejected from the nozzle portion 9 to the target region. Here, in the injection completed state in which the injection of the injection liquid ML is completed, the contact portion 34 is in contact with the end surface of the first end portion 6a of the piston 6 as shown in the lower part of FIG. 5, but the plunger 7 is in contact with the nozzle portion. Since the nozzle holder 10 in which the 9 is formed is in contact with the inner wall surface, the sliding of the piston 6 is restricted. The position of the contact portion 34 in this state is the ejection position and is displayed by X2, and is the position on the syringe portion 5 side with respect to the position X0. The position of the plunger 7 is displayed on P2.

As described above, in the injector 1, in the process of combustion of the igniter 22, the contact portion 34 of the sealing member 8 moves from the starting position X1 in the pre-combustion state to the injection position X2 in the injection completed state. The moving distance (X2-X1) due to the movement of the contact portion 34 corresponds to the moving distance (P2-P1) of the plunger 7 for injecting the injection liquid ML. Then, with this movement, the sealing member 8 is deformed so as to be turned inside out. That is, the moving distance of the piston 6 and the plunger 7 required to inject the injection liquid ML is secured by the inside-out deformation of the sealing member 8. When the sealing member 8 is deformed inside out in this way, the sealing member 8 itself does not need to be significantly elastically deformed, and the displacement of the intermediate portion 36 and the contact portion 34 excluding the fixed end portion 35 is the main component. Even if the intermediate portion 36 expands as a result of the contact portion 34 being largely displaced toward the syringe portion 5 due to the injection energy generated by the combustion of the igniter 22, the intermediate portion 36 is first displayed in the upper part of FIG. It moves to the syringe portion 5 side from the state shown in the above, and then expands with the displacement of the contact portion 34. Therefore, it is possible to suppress the amount of elastic deformation of the intermediate portion 36 itself to be small, and it is possible to suppress damage to the sealing member 8 while sufficiently securing the moving distance of the plunger 7 for injecting the injection liquid ML. .. This makes it possible for the sealing member 8 to sufficiently suppress the contamination of the combustion product with the injection liquid.

Further, as described above, the diameter d1 of the first end portion 6a of the piston 6 is configured to be smaller than the inner diameter d0 of the through hole 37. Therefore, when the above-mentioned sealing member 8 is deformed by turning over, the intermediate portion 36 enters the gap between the first end portion 6a and the through hole 37, and the intermediate portion 36 is deformed by turning over along the inner wall surface of the through hole 37. And it becomes possible to smoothly extend. The contact portion 34 does not necessarily have to be in contact with the end surface of the first end portion 6a of the piston 6 when it is in the injection position, as long as the piston 6 is slid for injection of the injection liquid ML. The contact portion 34 may be in a non-contact state with the end face when the injection position is reached.

<Second Embodiment>
FIG. 6 shows a second embodiment of the present invention. The first embodiment is configured to cause the injection energy of the initiator 20 to act on the piston 6 via the sealing member 8, and the sealing member 8 is directly exposed to the combustion gas. On the other hand, in the present embodiment, the injection energy is once propagated to the piston 60 and then indirectly acts on the piston 6 via the sealing member 8, and the sealing member 8 is directly exposed to the combustion product. It can be suppressed. In the present embodiment, the injector main body 2 is formed by the first housing 3A and the second housing 4, and the same reference number is given to the substantially same configuration as the first embodiment. The detailed description thereof will be omitted.

A combustion chamber 31 is formed in the first housing 3A, and the combustion chamber 31 is configured to diffuse the combustion products produced by the initiator 20. Here, a metal piston 60 is further arranged in the combustion chamber 31 and is slidably held in the combustion chamber 31. One end of the piston 60 faces the initiator 20, and the other end is arranged so as to sandwich the contact portion 34 of the sealing member 8 with the first end portion 6a of the piston 6. Therefore, when the igniter 22 is burned by the operation of the initiator 20, the injection energy is input to the end portion of the piston 60 facing the initiator 20, and then transmitted to the piston 6 via the contact portion 34 of the sealing member 8. go. Therefore, the combustion of the igniter 22 causes the piston 6 to slide together with the piston 60. Also at this time, the sealing member 8 is deformed to be turned inside out in the same manner as in the first embodiment described above. In particular, in the present embodiment, since the contact portion 34 is sandwiched between the piston 6 and the piston 60, the deformation of the sealing member 8 is restricted in a specific direction, and thus the above-mentioned inside-out deformation occurs. It will be easier to do smoothly. Further, in the present embodiment, since the injection energy is once input to the piston 60, it is possible to suppress the sealing member 8 from being directly exposed to the combustion product, and as a result, the sealing member 8 is engaged. Thermal stress can be reduced, and its damage can be suppressed more reliably.

<Example 1>
In the injector 1 according to the first embodiment, a confirmation experiment was conducted to confirm whether or not the sealing by the sealing member 8 at the time of explosive combustion in the initiator 20 is achieved. As the material of the sealing member 8, NBR (nitrile rubber) is adopted as the rubber material, and the sealing member 8 is damaged when the hardness of the rubber material and the temperature condition of the injector 1 at the time of operation are changed. Was visually confirmed.

Specifically, the hardness of the rubber material is 50 degrees and 70 degrees. Further, there are three types of temperature conditions for the injector 1: high temperature (50 degrees), normal temperature (20 degrees), and low temperature (0 degrees). Further, the pressure in the combustion chamber 31 at the time of burning the explosive has a peak value of 30 MPa, and the thickness of the sealing member 8 is 1 mm. As a result of performing explosive combustion of the initiator 20 three times under each hardness and temperature condition and confirming the number of times that the sealing member 8 was found to be damaged, no damage was observed under all the conditions.

<Example 2>
In the injector 1 according to the second embodiment, a confirmation experiment was conducted to confirm whether or not the sealing by the sealing member 8 at the time of explosive combustion in the initiator 20 is achieved. Chloroprene and NBR are used as the rubber materials for the sealing member 8, and the sealing member 8 is damaged when the temperature conditions of the injector 1 at the time of operation are changed in each rubber material. It was confirmed visually.

Specifically, when chloroprene is used as the rubber material, its hardness is 65 degrees, and when NBR is used, its hardness is 70 degrees. Further, there are three types of temperature conditions for the injector 1: high temperature (50 degrees), normal temperature (20 degrees), and low temperature (0 degrees). Further, the pressure in the combustion chamber 31 at the time of burning the explosive has a peak value of 30 MPa, and the thickness of the sealing member 8 is 1 mm. As a result of performing explosive combustion of the initiator 20 three times under each rubber material and temperature condition and confirming the number of times that the sealing member 8 was found to be damaged, no damage was found under all the conditions.

From the above, it can be understood that NBR can be suitably adopted as the rubber material for forming the sealing member 8 in any of the embodiments. Further, in the second embodiment, chloroprene can be further adopted as the rubber material. The results of the above examples are merely examples, and by adjusting the hardness of the rubber material or limiting the temperature conditions of the injector 1, chloroprene can be used as the rubber material even in the first embodiment. It is also possible to adopt it as a rubber.

<Other Examples>
According to the injector 1 according to the present invention, in addition to the case of injecting the above-mentioned injection solution into a skin structure, for example, in the field of regenerative medicine for humans, cultured cells are added to target cells, scaffold tissues, and scaffolds. , Stem cells, etc. can be seeded. For example, as shown in Japanese Patent Application Laid-Open No. 2008-206477, cells that can be appropriately determined by those skilled in the art depending on the site to be transplanted and the purpose of recellularization, such as endothelial cells, endothelial precursor cells, bone marrow cells, and anterior bones. It is possible to inject blast cells, cartilage cells, fibroblasts, skin cells, muscle cells, liver cells, kidney cells, intestinal cells, stem cells, and any other cells considered in the field of regenerative medicine with the injector 1. be. More specifically, the liquid (cell suspension) containing the cells to be seeded is housed in the storage chamber 33, and the pressure is applied to the liquid (cell suspension) to inject and transplant the predetermined cells to the site to be transplanted. ..

Furthermore, the injector 1 according to the present invention can also be used for delivering DNA or the like to cells, scaffold tissues, scaffolds, etc., as described in Japanese Patent Publication No. 2007-525192. In this case, it can be said that it is more preferable to use the injector 1 according to the present invention because the influence on the cells, the scaffold tissue, the scaffold, etc. can be suppressed as compared with the case of delivery using a needle.

Furthermore, the injector 1 according to the present invention is also used when various genes, tumor suppressor cells, lipid envelopes, etc. are directly delivered to a target tissue, or an antigen gene is administered to enhance immunity against a pathogen. It is preferably used. In addition, in the fields of various disease treatments (fields described in JP-A-2008-50881, JP-A-2010-503616, etc.), immunomedical fields (fields described in JP-A-2005-523679, etc.), etc. , The injector 1 can be used, and its usable field is not intentionally limited.

1 ... Injector 2 ... Injector body 5 ... Syringe part 6 ... Piston 7 ... Plunger 8 ... Sealing member 9 ... Nozzle part 10 ····························································································································································.・ ・ Fixed end 36 ・ ・ ・ ・ Intermediate 37 ・ ・ ・ ・ Through hole 60 ・ ・ ・ ・ Piston

Claims (7)

An injector that injects the target substance into the target area.
An injector body with a through hole formed in the axial direction,
A first piston portion slidably arranged in the through hole and
A syringe portion arranged on the tip end side of the injector body, a storage chamber capable of accommodating the target substance, and a plunger that pressurizes the target substance in the accommodation chamber as the first piston portion slides. A syringe portion including a flow path through which the target substance flows in the containment chamber pressurized by the plunger, and a nozzle portion for ejecting the target substance from an injection port formed at the tip of the flow path.
An ignition device that burns explosives, and an ignition device that applies injection energy for injecting the target substance from the nozzle portion to the first piston portion by burning the explosive in the ignition device.
The space inside the injector body is divided into a first space in which the ignition device is arranged and a second space in which the first piston portion is arranged, and the combustion product produced by the ignition device is referred to as the combustion product. The sealing member to be sealed in the first space and
Equipped with
The first piston portion has a plunger side end portion that comes into contact with the plunger and a predetermined end portion having a predetermined end surface that receives the injection energy.
The sealing member is
A fixed end fixed to the inner wall defining the space inside the injector body,
A contact portion that comes into contact with the predetermined end face of the predetermined end portion when the explosive is burned in the ignition device.
Have,
The fixing force of the fixed end portion to the inner wall is larger than the sliding force of the first piston portion in the through hole.
In the state before the combustion of the explosive in the ignition device, the contact portion is located at the starting position on the ignition device side with respect to the fixed end portion.
Due to the combustion of gunpowder in the ignition device, the sealing member is displaced except for the fixed end portion, so that the contact portion comes into contact with the predetermined end surface, the first piston portion slides, and the fixed end portion is used. It is configured to move to the injection position on the syringe portion side with respect to the portion.
Injector. The syringe portion is configured to be attachable to the injector body.
When the syringe portion is attached to the injector main body, a contact state is formed in which the first piston portion contacts the plunger.
The fixing force of the fixed end portion to the inner wall is further set to be larger than the force of pushing the target substance contained in the storage chamber toward the nozzle portion by the plunger when the syringe portion is attached.
The injector according to claim 1. Before the syringe portion is attached to the injector main body, the first piston portion is configured to be able to be pushed into the through hole from the plunger side end portion side.
The injector according to claim 1 or 2. The sealing member is made of an elastic member.
The injector according to any one of claims 1 to 3. The sealing member covers the side surface portion of the predetermined end portion along the sliding direction of the first piston portion in the state before the combustion of the explosive in the ignition device, and is between the fixed end portion and the contact portion. Further has an intermediate portion formed in
As the first piston portion slides due to the combustion of gunpowder in the ignition device, the contact portion moves from the starting position to the injection position while the intermediate portion extends in the sliding direction.
The injector according to claim 4. The outer diameter of the first piston portion at the predetermined end portion is smaller than the inner diameter of the through hole.
With the sliding of the first piston portion due to the combustion of gunpowder in the ignition device, the intermediate portion extends in the sliding direction along the inner wall surface of the through hole.
The injector according to claim 5. A second piston portion that is more slidable in the through hole and is arranged on the first space side, and sandwiches the contact portion of the sealing member together with the predetermined end surface of the first piston portion. Further equipped with an arranged second piston part,
The second piston portion is a first portion that faces the ignition device and transmits the injection energy to the predetermined end surface of the first piston portion via the contact portion and the ignition device side end portion to which the injection energy is input. With a piston portion side end,
The injector according to any one of claims 1 to 6.

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