Container unit for syringe and syringe

Abstract

Provided is a container unit for a syringe, the container unit comprising: a container including an accommodation space for accommodating an injection liquid; and a container holder to which the container can be detachably attached and which is used in a state of having the container attached thereto when the syringe is used. The container holder includes a nozzle part having an injection port for injecting the injection liquid when the syringe is used, and a nozzle flow path for guiding the injection liquid from the accommodation space to the injection port when the syringe is used. The container has a filling opening part for directly filling the accommodation space with the injection liquid from the outside when the container is in a state of being detached from the container holder. The filling opening part is configured to be in communication with the nozzle flow path when the container is in a state of being attached to the container holder. The opening cross-sectional area of the filling opening part is larger than the opening cross-sectional area of the injection port.

Description

Container unit for syringe and syringe

[0001] The present disclosure relates to a container unit for a syringe, and to a syringe.

[0002] Known devices for injecting a medicinal solution or the like into a target area of ​​a living body include needle-equipped syringes that inject the injection solution into the target area via a syringe needle and needleless syringes that inject the injection solution into the target area without using a syringe needle. In recent years, needleless syringes have been particularly attracting attention for their ease of handling and hygienic aspects, and their development has been progressing. Generally, needleless syringes have been put to practical use in which a medicinal solution pressurized by a driving source such as compressed gas or a spring is injected toward the target area, and the kinetic energy of the medicinal solution is utilized to inject the medicinal solution into the target area.

[0003] For example, Patent Document 1 discloses a needleless syringe having a reservoir for accommodating an injection solution, and Patent Document 2 discloses a syringe in which a lateral hole is formed in the reservoir for accommodating the injection solution and the injection solution is filled therein.

[0004] International Publication No. WO 2022 / 004334 International Publication No. WO 1994 / 013541

[0005] Syringes usually require injection liquid to be injected at high pressure from the injection port, which is formed as a fine hole. Therefore, in conventional syringes, when filling the injection liquid storage section with the injection liquid, the injection liquid must be sucked through the injection port formed as a fine hole, and this filling operation takes time, especially when the injection liquid is highly viscous.

[0006] The technology of the present disclosure has been made in consideration of the above-described circumstances, and its purpose is to provide technology relating to a container unit for a syringe that can quickly fill with an injection solution.

[0007] In order to solve the above problems, the container unit for a syringe of the present disclosure employs the following configuration: That is, the technology of the present disclosure is a container unit for a syringe, comprising: a container having a storage space for storing an injection solution; and a container holder to which the container can be detachably attached and which is used with the container attached when the needleless syringe is in use (activated), the container holder comprising a nozzle part having an ejection port through which the injection solution is ejected when the syringe is in use (activated) and a nozzle flow path that guides the injection solution from the storage space to the ejection port when the syringe is in use (activated), the container has a filling opening for directly filling the storage space with the injection solution from the outside when the container is removed from the container holder, the filling opening is configured to communicate with the nozzle flow path when the container is attached to the container holder, and the opening cross-sectional area of ​​the filling opening is larger than the opening cross-sectional area of ​​the ejection port.

[0008] In the syringe container unit of the present disclosure, when the container is attached to the container holder, a base-end opening formed on the base end of the nozzle channel may be arranged opposite the filling opening. By arranging the base-end opening and the filling opening opposite each other in this manner, the flow of the injection liquid becomes smooth, allowing the pressurized injection liquid to be injected without decelerating. Furthermore, the pressure applied from inside the container and the container holder is reduced, improving durability.

[0009] The container unit for a syringe disclosed herein may be configured such that, when the container is attached to the container holder, the proximal opening of the container holder is included within a projected area of ​​the filling opening projected along the axial direction of the container unit. By configuring the proximal opening of the container holder to be included within a projected area of ​​the filling opening projected along the axial direction of the container unit, the flow of the injection solution becomes smooth, allowing the pressurized injection solution to be injected without decelerating. Furthermore, the pressure applied from inside the container and the container holder is reduced, improving durability.

[0010] In the syringe container unit of the present disclosure, the base-end opening and the filling opening may be coaxially arranged when the container is attached to the container holder. By arranging the base-end opening and the filling opening coaxially, the flow of the injection liquid becomes smooth, allowing the pressurized injection liquid to be injected without decelerating. Furthermore, the pressure applied from inside the container and the container holder is reduced, improving durability.

[0011] The technology of the present disclosure may be a syringe including a container unit for a syringe and a housing configured to detachably attach the container unit. The syringe may be a needleless syringe or a needle syringe.

[0012] The technology disclosed herein provides a technology relating to a container unit for a syringe that can quickly fill with an injection solution.

[0013] FIG. 1 is an overall view of a needle-free syringe according to an embodiment. FIG. 2 is a cross-sectional view of the needle-free syringe. FIG. 3 is a structural view of a container unit for a needle-free syringe. FIG. 4 is an enlarged view of FIG. 3 showing a container and a container holder of the container unit. FIG. 5 is an assembled cross-sectional view of the container unit and plunger. FIG. 6 is a view for explaining a method of filling the container unit with an injection solution.

[0014] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In this disclosure, a needleless syringe that injects an injection solution into a target area without using an injection needle is exemplified as an example of a syringe. However, the technology of the present disclosure may also be applied to a needle-type syringe that injects an injection solution into a target area via an injection needle. Note that the configurations and combinations thereof in each embodiment are merely examples, and additions, omissions, substitutions, and other modifications of the configurations may be made as appropriate within the scope of the present invention. The present disclosure is not limited by the embodiments, but is limited only by the claims.

[0015] <Embodiment> Fig. 1 is an overall view of a needle-free syringe 1 according to an embodiment. Fig. 2 is a cross-sectional view of the needle-free syringe 1. Here, the needle-free syringe 1 is formed by attaching a syringe assembly 10 to a housing 20. The needle-free syringe 1 is a needle-free syringe that uses the combustion energy of gunpowder to inject an injection liquid L into a target area, i.e., a device that performs an injection by injecting the injection liquid L into a target area without using an injection needle.

[0016] In this embodiment, the terms "distal side" and "base end side" are used to indicate the relative positional relationship in the longitudinal direction of the needle-free syringe 1. The "distal side" indicates a direction toward the tip of the needle-free syringe 1, which will be described later, i.e., a position toward the injection port 1022b, and the "base end side" indicates a direction opposite to the "distal side" in the longitudinal direction of the needle-free syringe 1, i.e., a position toward the housing 20.

[0017] In the following description of the present disclosure, the injection liquid L injected into the target area by the needleless syringe 1 is formed by containing a predetermined substance that exerts the efficacy or function expected in the target area in a liquid medium. In the injection liquid L, the predetermined substance may be dissolved in the liquid medium, or may simply be mixed without being dissolved.

[0018] Examples of the predetermined substance contained in the injection solution L include, for example, biologically-derived substances that can be injected into a target area of ​​a living body, or substances that exhibit desired physiological activity. Examples of biologically-derived substances include DNA, RNA, nucleic acids, antibodies, and cells. Examples of physiologically-active substances include medicines made of low-molecular-weight molecules, proteins, and peptides, vaccines, inorganic substances such as metal particles for thermotherapy and radiotherapy, and various substances with pharmacological or therapeutic effects, including carriers. Furthermore, the liquid medium for the injection solution L may be any substance suitable for administering these predetermined substances into the target area, regardless of whether it is aqueous or oil-based. Furthermore, the viscosity of the liquid medium is not particularly limited, as long as the predetermined substance can be injected using the needleless syringe 1.

[0019] Furthermore, the target region into which the injection liquid L is injected is the region into which the injection liquid L is to be administered, and examples thereof include living body cells and tissues (skin, etc.), and organs (eyeballs, heart, liver, etc.). It should be noted that, as long as there is no problem, it is also possible to set a biological component as the target region in a state where it is separated from the living body. In other words, the scope of the operation of the syringe according to this embodiment is not limited to in-vivo target regions, but also includes injection of a predetermined substance into ex-vivo target regions (tissues and organs) and injection of a predetermined substance into in-vitro target regions (cultured cells and cultured tissues).

[0020] [Overall Structure] As shown in Fig. 1, the needle-free syringe 1 includes a syringe assembly 10, a housing 20 to which the syringe assembly 10 can be attached, and a power cable 30 for supplying a driving current to the syringe assembly 10 in the housing 20. In the needle-free syringe 1, the syringe assembly 10 is configured to be detachable from the housing 20. As shown in Fig. 2, the syringe assembly 10 is an assembly including an actuator 101, a container unit 102, an attachment 103, and a plunger 104. An accommodation space 10a formed in a container 1021 (described below) included in the syringe assembly 10 is filled with an injection liquid L according to a filling method for an injection liquid (described below) in a preparation stage before use (before activation) of the needle-free syringe 1. The syringe assembly 10 is a unit that is replaced each time the injection liquid L is injected. In other words, when using the needle-free syringe 1, the syringe assembly 10 including the actuator 101 and the container unit 102 is connected to the housing 20 and activated, and after using the needle-free syringe 1, the syringe assembly 10 is removed from the housing 20 and replaced.

[0021] The actuator 101 is a component that generates energy for the needle-free syringe 1 to inject the injection liquid L. As shown in FIG. 2 , the actuator 101 includes a body 101a, an initiator 101b, and a piston 101c. The actuator 101 uses the initiator 101b as an actuation source and the piston 101c as an output unit. The body 101a is cylindrical and has an opening 101d at its tip. The initiator 101b is an electric igniter that releases combustion products by burning an ignition charge and is fitted into the body 101a so as to close the base end of the body 101a. The piston 101c is disposed between the initiator 101b and the opening 101d so as to be able to slide longitudinally inside the body 101a. The space between the initiator 101b and the piston 101c forms a combustion chamber 101e into which the combustion products are released.

[0022] Examples of ignition charges used in the initiator 101b include zirconium and potassium perchlorate (ZPP), titanium hydride and potassium perchlorate (THPP), titanium and potassium perchlorate (TiPP), aluminum and potassium perchlorate (APP), aluminum and bismuth oxide (ABO), aluminum and molybdenum oxide (AMO), aluminum and copper oxide (ACO), aluminum and iron oxide (AFO), or a combination of these explosives. These explosives generate high-temperature, high-pressure plasma during combustion immediately after ignition, but when the combustion products return to room temperature and condense, the generated pressure drops rapidly because they do not contain gas components. Other explosives may also be used as ignition charges as long as they are capable of ejecting the appropriate injection liquid L.

[0023] The container unit 102 is a member for containing the injection liquid L. The container unit 102 includes a container 1021 and a container holder 1022. FIG. 3 is a structural diagram of the container unit 102 of the needleless syringe 1. The container 1021 can be detachably attached to the container holder 1022. Both the container 1021 and the container holder 1022 are formed in a substantially cylindrical shape. When the container 1021 is attached to the container holder 1022, the central axis of the container 1021 and the central axis of the container holder 1022 are coaxial. A storage space 10a for containing the injection liquid L is formed inside the container 1021. The container holder 1022 is formed with a nozzle portion 1022a having a truncated cone-shaped nozzle flow path 1022f. An injection port 1022b is formed at the tip of the nozzle portion 1022a, and is configured to be able to inject the injection liquid L. Details of the container unit 1022 will be described later.

[0024] The attachment 103 is a member that connects the body 101a and the container unit 102. The attachment 103 is formed in a substantially cylindrical shape, and the actuator 101 is fitted into the base end side of the internal space of the attachment 103, and the container holder 1022 is screwed onto the tip end side of the attachment 103. The inner peripheral surface of the attachment 103 is screwed onto the outer peripheral surface of the body 101a, and the inner peripheral surface of the attachment 103 is screwed onto the outer peripheral surface of the container holder 1022, thereby connecting the body 101a and the container unit 102 via the attachment 103.

[0025] The plunger 104 is a member that pressurizes the injection liquid L by energy received from the actuator 101. The plunger 104 is housed in the attachment 103 and disposed between the actuator 101 and the filling opening 1021a of the container 1021. The plunger 104 is formed in a rod shape, and its base end engages with the tip end of the piston 101c. The tip end of the plunger 104 is inserted into the accommodation space 10a formed inside the container 1021. As shown in FIG. 3 , when the container 1021, the container holder 1022, and the plunger 104 are assembled, the central axis of the plunger 104, the central axis of the container 1021, and the central axis of the container holder 1022 are coaxial. In this embodiment, all of the central axes are collectively referred to as a central axis C.

[0026] The housing 20 is a component that houses the syringe assembly 10 and functions as a grip that a user holds when using the needle-free syringe 1. The outer surface of the housing 20 is provided with a plurality of switches, such as a switch 201, that operate the needle-free syringe 1 to eject the injection liquid L. The plurality of switches are connected to a control unit (not shown), such as a microcomputer, built into the housing 20. The inner surface of the housing 20 is provided with a socket (not shown) that is connected to the initiator 101b of the syringe assembly 10. Power is supplied to the control unit and the initiator 101b via a power cable 30 connected to the housing 20. The control unit controls the supply of drive current to the initiator 101b based on signals from each switch, thereby controlling the operation of the needle-free syringe 1.

[0027] When a drive current is supplied to the initiator 101b by user operation and the initiator 101b is activated, combustion products are released from the initiator 101b into the combustion chamber 101e. When the pressure in the combustion chamber 101e rises, the piston 101c receives the pressure and slides toward the tip of the body 101a. This pushes the plunger 104 engaged with the piston 101c toward the tip, and injection energy is imparted to the injection liquid L contained in the containing space 10a. This causes the injection liquid L to be injected from the injection port 1022b formed at the tip of the nozzle portion 1022a. The kinetic energy of the injection liquid L ruptures the surface of the target area, such as the skin, and the injection liquid L is injected into the target area.

[0028] [Container Unit] Fig. 4 is an enlarged view of Fig. 3 relating to the container 1021 and the container holder 1022 of the container unit 102. Fig. 5 is an assembled cross-sectional view of the container unit 102 and the plunger 104. The container unit 102 will be described in detail below with reference to Figs. 3, 4 and 5.

[0029] The container 1021 is formed, for example, in a substantially cylindrical shape. A filling opening 1021a is formed at the tip of a cylindrical storage space 10a formed inside the container 1021. As will be described in detail later, this filling opening 1021a is an opening used when filling the storage space 10a of the container 1021 with the injection liquid L. A taper 1021b is formed at the tip side of the storage space 10a so that the diameter decreases toward the filling opening 1021a. A thread 1021s that can be threaded with the container holder 1022 is formed on the outer circumferential surface of the container 1021. The filling opening 1021a is formed, for example, as a circular through-hole formed around the central axis C. By arranging the filling opening 1021a on the central axis C, the flow of the injection liquid L is smooth, allowing the pressurized injection liquid L to be injected without deceleration. Furthermore, the pressure applied from inside to the container 1021 and the container holder 1022 is reduced, improving durability. The filling opening 1021a is formed so that the injection liquid L can be supplied from the storage space 10a to a nozzle flow path 1022f (described later) when the needleless syringe 1 is in use (activated), and so that the injection liquid L can be directly filled into the storage space 10a when the container 1021 is detached from the container holder 1022. A method for filling the storage space 10a with the injection liquid L will be described later. The taper 1021b is formed by narrowing the diameter of the tip of the storage space 10a from the base end to the tip end, and is formed as an inclined wall surface for smoothly guiding the injection liquid L or air bubbles in the storage space 10a to the nozzle portion 1022a (described later). However, the shape of the container 1021 is not limited to a cylindrical shape and may be appropriately changed to match the shape of the housing 20 or the attachment 103. The presence or absence and form of the taper 1021b may also be appropriately changed. Furthermore, the cross-sectional shape of the opening of the filling opening 1021a is not limited to a circular shape and may be a triangular, rectangular, or other shape. For example, if the cross section of the filling opening 1021a has a shape with corners, when filling the container 1021 with the injection liquid L, a part of the tool used for filling (for example, a pipette tip attached to a micropipette) can be supported by contacting the side near the corners at two points, thereby holding the tip of the tool in a stable position.As a result, the filling operation of the injection liquid L can be carried out stably, which in turn contributes to reducing the formation of bubbles during filling.

[0030] The container holder 1022 is formed, for example, in a substantially cylindrical shape. The cylindrical interior defines an internal space into which the container 1021 can be fitted, and a thread 1022s is formed on the wall of the internal space so that the container 1021 can be threadedly engaged. As a result, as shown in FIG. 5 , the container unit 102 can detachably attach the container 1021 to the container holder 1022 by threading the thread 1022s formed on the inner peripheral surface of the container holder 1022 with the thread 1022s formed on the outer peripheral surface of the container 1021. In addition, a thread is formed on the outer peripheral surface of the container holder 1022 so that the attachment 103 can be threadedly engaged with the container holder 1022. A nozzle portion 1022a is formed at the tip of the container holder 1022, and the nozzle portion 1022f includes a nozzle flow path 1022f that communicates with the storage space 10a formed in the container 1021 via the filling opening 1021a when the container 1021 is attached to the container holder 1022. An ejection port 1022b, which is a circular through-hole formed around the central axis C, is formed at the tip of the nozzle portion 1022a. A base-end opening 1022c, which is a circular through-hole formed around the central axis C and allows the injection liquid L to flow into the ejection port 1022b, is formed at the base-end side. As will be described in detail later, when the needle-free syringe 1 (initiator 101b) is activated, the injection liquid L contained in the container 1021 flows into the nozzle flow path 1022f of the container holder 1022 through the filling opening 1021a and is ejected at high pressure from the ejection port 1022b. In this embodiment, the cross-sectional shape of the filling opening 1021a may be the same as the base-end opening 1022c, which has the advantage of allowing the injection liquid L to be smoothly guided.

[0031] As shown in FIG. 4 , the nozzle portion 1022a is formed with a truncated conical nozzle flow channel 1022f, the opening cross-sectional area of ​​which gradually decreases from the base-end opening 1022c toward the ejection port 1022b. The opening cross-sectional area of ​​the nozzle flow channel 1022f is the cross-sectional area of ​​the needle-free syringe 1 in a direction perpendicular to the central axis C. The nozzle flow channel 1022f is a space defined by the base-end opening 1022c on the base side and the ejection port 1022b on the tip side. The nozzle flow channel 1022f is a flow channel for the injection liquid L, which is formed so that the injection liquid L flows from the storage space 10a to the ejection port 1022b when the needle-free syringe 1 is in use (activated). By changing the shape of the nozzle flow channel, the injection pressure of the injection liquid L ejected from the ejection port 1022b can be adjusted.

[0032] When the container 1021 is attached to the container holder 1022, the central axis of the container holder 1022 and the central axis of the container 1021 are coaxially aligned, so that the base-end opening 1022c and the filling opening 1021a are coaxially aligned. The base-end opening 1022c and the filling opening 1021a are also positioned opposite each other. As a result, when the needle-free syringe 1 is in use (activated), the injection liquid L contained in the housing space 10a is supplied to the nozzle flow path 1022f via the filling opening 1021a and the base-end opening 1022c, and the injection liquid L is injected from the injection port 1022b.

[0033] The shape of the container holder 1022 is not particularly limited and may be changed as appropriate to match the shapes of the housing 20 and the attachment 103. Furthermore, the cross-sectional shapes of the base-end opening 1022c and the injection port 1022b are not limited to being circular, and may be triangular, rectangular, or the like.

[0034] The cross-sectional area of ​​the filling opening 1021a is larger than that of the injection port 1022b. The cross-sectional area here refers to the cross-sectional area of ​​the needle-free syringe 1 in a direction perpendicular to the central axis C. The cross-sectional area of ​​the filling opening 1021a may also be larger than that of the base-end opening 1022c. By making the cross-sectional area of ​​the filling opening 1021a larger than that of the base-end opening 1022c, the flow of the injection liquid L becomes smoother, allowing the pressurized injection liquid L to be injected without decelerating. Furthermore, the smooth flow of the pressurized injection liquid L as described above can reduce the pressure applied from the inside to the container 1021 and the container holder 1022, improving their durability. In this embodiment, the filling opening 1021a and the base-end opening 1022c are both circular and are formed to allow the injection liquid L to pass through. In this embodiment, the opening diameter of the filling opening 1021a may be 0.8 mm to 4.85 mm, and the opening diameter of the base end opening 1022c may be 0.8 mm. The opening cross-sectional area of ​​the ejection port 1022b is designed to an appropriate size depending on the design injection pressure of the injection liquid L ejected from the ejection port 1022b when the needle-free syringe 1 (initiator 101b) is activated, and may have an opening diameter of, for example, approximately 0.1 mm. By forming the opening cross-sectional area of ​​the filling opening 1021a larger than that of the ejection port 1022b, it is possible to easily fill the containing space 10a with the injection liquid L during the filling process described below. However, the shapes and opening diameters of the filling opening 1021a and the base end opening 1022c described above are merely exemplary and are not limited thereto.

[0035] Furthermore, the container unit 102 in this embodiment is configured such that, when the container 1021 is attached to the container holder 1022, the nozzle flow path 1022f of the container holder 1022 is included within a projection area of ​​the filling opening 1021a projected in a direction along the central axis C of the container unit 102. In other words, the base-end opening 1022c of the container holder 1022 is included within the projection area of ​​the above-mentioned filling opening 1021a. This prevents the base-end opening 1022c of the container holder 1022 from being blocked by the edge portion that forms the filling opening 1021a in the container 1021 when the container 1021 is attached to the container holder 1022. This allows the injection solution L to be smoothly guided from the accommodation space 10a to the nozzle flow path 1022f when the needleless syringe 1 is in use (activated).

[0036] Reference numeral 1021c shown in FIG. 4 denotes an outer surface formed on the tip side of the container 1021 (hereinafter referred to as a "tip abutting outer surface"). Reference numeral 1022d denotes an inner surface formed on the tip side of the container holder 1022 (hereinafter referred to as a "tip abutting inner surface"). For example, when the container 1021 is attached to the container holder 1022, the tip abutting outer surface 1021c of the container 1021 and the tip abutting inner surface 1022d of the container holder 1022 are in contact with each other. In the container unit 102 of this embodiment, a sealing material such as an O-ring or a packing may be disposed between the tip abutting outer surface 1021c of the container 1021 and the tip abutting inner surface 1022d of the container holder 1022. This allows the gap between the tip abutting outer surface 1021c of the container 1021 and the tip abutting inner surface 1022d of the container holder 1022 to be sealed. As a result, leakage of the injection solution L from between the tip abutting outer surface 1021c and the tip abutting inner surface 1022d can be suppressed. The above-mentioned sealing material may be provided on either the tip abutting outer surface 1021c side or the tip abutting inner surface 1022d side. For example, an annular recess may be provided around the base-end opening 1022c on the tip abutting inner surface 1022d of the container holder 1022, and a sealing material such as an O-ring may be disposed in the recess. Alternatively, an annular recess may be provided around the filling opening 1021a on the tip abutting outer surface 1021c of the container 1021, and a sealing material such as an O-ring may be disposed in the recess. However, the form of the groove for disposing the sealing material, the material of the sealing material, and the like are not particularly limited.

[0037] [Method of Filling Injection Solution] FIG. 6 is a diagram illustrating a method of filling the container unit 102 (container 1021) with the injection solution L. In each of (a) to (e) of FIG. 6, the tip end side of the container unit 102 (container 1021) is shown as the upper side of the page, and the base end side of the container unit 102 (container 1021) is shown as the lower side of the page. The operation of filling the accommodation space 10a of the container 1021 with the injection solution L is typically performed while the filling opening 1021a formed on the tip end side of the container 1021 faces upward. Hereinafter, with reference to (a) to (e) of FIG. 6, the method of filling the accommodation space 10a of the container 1021 with the injection solution L and the subsequent method of assembling the container unit 102 and the plunger 104 will be described in five steps.

[0038] 6A is a diagram for explaining step S1, showing a state in which the plunger 104 is inserted into the container 1021. By inserting the plunger 104 into the container 1021, the opening formed on the rear end side of the container 1021 is closed, and preparations are made so that the injection liquid L can be filled into the storage space 10a.

[0039] 6(b) is a diagram illustrating step S2, showing the state in which the injection liquid L is being filled into the storage space 10a using a filling tool 2 such as a micropipette or a syringe. The opening cross-sectional area of ​​the filling opening 1021a of the container 1021 is large enough to allow the tip of the filling tool 2 to be inserted, for example. For example, the size of the opening cross-sectional area of ​​the filling opening 1021a is designed from the perspective of the filling ability (filling efficiency) of the injection liquid L into the storage space 10a, and is designed without relying on the injection pressure of the injection liquid L injected from the nozzle portion 1022a when the needle-free syringe 1 is in use (when the initiator 101b is activated). In this embodiment, the injection liquid L can be directly filled into the storage space 10a from the outside with the tip of the filling tool 2 inserted into the filling opening 1021a, so the filling operation of the injection liquid L can be performed efficiently and easily in a short time. Therefore, even if the injection liquid L to be filled into the accommodation space 10a of the container 1021 has high viscosity, it is possible to easily fill the injection liquid L in a short time. Note that the above-mentioned filling device 2 is not limited to a micropipette or a syringe, and may be other types of devices.

[0040] 6(c) is a diagram illustrating step S3, showing a state in which the container holder 1022 is fitted into the container 1021 in the direction of arrow A1. The container holder 1022 is fitted into the container 1021, and the screws 1021s and 1022s are screwed together to assemble the container 1021, thereby attaching the container 1021 to the container holder 1022 and completing the container unit 102. In this state, the filling opening 1021a of the container 1021 and the nozzle flow path 1022f (including the injection port 1022b and the base-end opening 1022c) in the container unit 102 are coaxially arranged.

[0041] FIG. 6(d) is a diagram illustrating step S4, showing the state in which the plunger 104 inserted into the container 1021 is pushed in the direction of arrow A2. When the injection liquid L is filled into the storage space 10a in step S2, a gap may be formed between the liquid surface of the injection liquid L and the filling opening 1021a. In this case, the plunger 104 is pushed in a predetermined amount so that the gap is filled with the injection liquid L. This pressurizes the injection liquid L filled in the storage space 10a, causing a small amount of injection liquid L to be ejected from the ejection port 1022b. At this time, air bubbles in the storage space 10a can also be ejected to the outside from the ejection port 1022b along with the small amount of injection liquid L. This allows the storage space 10a and the nozzle flow path 1022f to be filled with the injection liquid L without containing any air bubbles. In this way, by facing the tip side of the container unit 102 upward and the base side downward and injecting a small amount of injection liquid L from the injection port 1022b, air bubbles contained in the injection liquid L and air present in the flow path of the injection liquid L can be easily removed.

[0042] 6(e) is a diagram illustrating step S5, showing a state in which the filling of the container 1021 with the injection solution L and the assembly of the container unit 102 are completed. In this state, the container unit 102 and the plunger 104 can be attached to the attachment 103. Thereafter, the threads provided on the outer peripheral surface of the container holder 1022 are threadedly engaged with the threads provided in the internal space of the attachment 103, thereby completing the connection between the container unit 102 and the attachment 103.

[0043] [Effects] As described above, the container unit 102 of the needle-free syringe 1 according to this embodiment comprises the container 1021 having the storage space 10a for storing the injection liquid L, and the container holder 1022 to which the container 1021 can be detachably attached and which is used with the container 1021 attached when the needle-free syringe 1 is used (activated). The container holder 1022 has an ejection port 1022b for ejecting the injection liquid L when the needle-free syringe 1 is used (activated), and an ejection port 1022c for ejecting the injection liquid L from the storage space 10a when the needle-free syringe 1 is used (activated). The container 1021 has a nozzle portion 1022a having a nozzle flow path 1022f that guides the injection liquid L to the nozzle 1022b, and the container 1021 has a filling opening 1021a for directly filling the injection liquid L from the outside into the storage space 10a when the container 1021 is removed from the container holder 1022, and the filling opening 1021a is configured to communicate with the nozzle flow path 1022f when the container 1021 is attached to the container holder 1022, and the opening cross-sectional area of ​​the filling opening 1021a is formed larger than the opening cross-sectional area of ​​the injection port 1022b.

[0044] Specifically, the container unit 102 in this embodiment employs a structure in which the nozzle portion 1022a having the injection port 1022b is formed not on the container 1021 side but on the container holder 1022 side which is detachable from the container 1021, and the filling opening 1021a is formed on the container 1021. An opening (injection port 1022b) for injecting the injection liquid L to the outside at high pressure when the needle-free syringe 1 is in use (activated), and an opening (filling opening 1021a) for filling the accommodation space 10a of the container 1021 with the injection liquid L are formed separately. In this way, the filling opening 1021a on the container 1021 side and the injection port 1022b on the container holder 1022 side are configured separately, so that the opening cross-sectional areas of the filling opening 1021a and the injection port 1022b can be individually and optimally designed according to the functions and specifications required of each. That is, typically, the ejection port 1022b, through which the injection liquid L is ejected to the outside at high pressure during use (activation) of the needle-free syringe 1, requires an opening cross-sectional area on the order of microns. Conventionally, when filling a container with injection liquid, it was necessary to aspirate the injection liquid through a fine-pore nozzle, which required a long time for the operation of filling the container with the injection liquid, and this inconvenience was particularly pronounced when the injection liquid had a high viscosity. In contrast, with the container unit 102 of this embodiment, the size of the filling opening 1021a can be designed independently, regardless of the injection pressure of the injection liquid L ejected from the ejection port 1022b during activation of the needle-free syringe 1 (initiator 101b). In other words, the size of the filling opening 1021a can be optimally designed, focusing primarily on the filling ability (filling efficiency) of the injection liquid L into the housing space 10a. With the container 1021 removed from the container holder 1022, the injection liquid L can be filled into the storage space 10a through the filling opening 1021a, which is optimally designed as described above, thereby allowing the injection liquid L to be filled into the storage space 10a quickly and easily.

[0045] Furthermore, in the needle-free syringe 1 according to this embodiment, when filling the holding space 10a with the injection liquid L, the filling opening 1021a of the container 1021 is positioned upward, and the filling tool 2 is used to directly fill the holding space 10a with the injection liquid L, so that no gap through which air can enter is formed between the injection liquid L and the tip of the plunger 104, thereby suppressing the generation of bubbles. Furthermore, even if bubbles are generated when filling the holding space 10a with the injection liquid L, the injection port 1022b is positioned upward when the container 1021 is attached to the container holder 1022, so that the bubbles can be easily and quickly removed by waiting for the bubbles to rise and then pressurizing the injection liquid L filled in the holding space 10a with the plunger 104.

[0046] In particular, in the needle-free syringe 1 of this embodiment, when the container 1021 is attached to the container holder 1022, the base end opening 1022c of the nozzle portion 1022a is arranged opposite the filling opening 1021a; when the container 1021 is attached to the container holder 1022, the base end opening 1022c of the container holder 1022 is included in a projected area of ​​the filling opening 1021a projected along the axial direction of the container unit 102; when the container 1021 is attached to the container holder 1022, the base end opening 1022c and the filling opening 1021a are arranged coaxially; and the size of the opening cross-sectional area of ​​the filling opening 1021a is equal to or larger than the opening cross-sectional area of ​​the base end opening 1022c. According to these configurations, even if the filling opening 1021a on the container 1021 side and the injection port 1022b on the container holder 1022 side are configured separately according to their respective specifications, when the needle-free syringe 1 is used (activated), the injection liquid L can be appropriately injected from the injection port 1022b without blocking the flow path of the injection liquid L.

[0047] Furthermore, in the container unit 102 of this embodiment, when the container 1021 is attached to the container holder 1022, the base-end opening 1022c of the nozzle flow path 1022f is disposed opposite the filling opening 1021a. This allows the pressurized injection liquid L to flow smoothly, allowing the pressurized injection liquid L to be ejected without decelerating. Furthermore, by smoothing the flow of the pressurized injection liquid L, the pressure applied from inside to the container 1021 and the container holder 1022 can be reduced, improving the durability of the container unit 102 and the needleless syringe 1. Furthermore, the container unit 102 of this embodiment is configured so that the base-end opening 1022c and the filling opening 1021a are disposed opposite each other. Therefore, even if air bubbles are generated when the injection liquid L is filled into the accommodation space 10a, the air bubbles can be easily and quickly removed from the ejection port 1022b by pressurizing the injection liquid L.

[0048] Furthermore, the container unit 102 of this embodiment is configured so that, with the container 1021 attached to the container holder 1022, the proximal opening 1022c of the container holder 1022 is included in a projection area of ​​the filling opening 1021a projected along the axial direction of the container unit 102. This makes it possible to smooth the flow of the pressurized injection liquid L when the needle-free syringe 1 is in use (activated), and the pressurized injection liquid L can be injected without decelerating. Furthermore, by smoothing the flow of the pressurized injection liquid L, it is possible to reduce the pressure applied from inside the container 1021 and the container holder 1022, improving the durability of the container unit 102.

[0049] Furthermore, in the container unit 102 of this embodiment, when the container 1021 is attached to the container holder 1022, the base-end opening 1022c and the filling opening 1021a are arranged coaxially. Furthermore, the base-end opening 1022c and the filling opening 1021a are arranged on the central axis C. As a result, the flow of the pressurized injection liquid L can be made smooth when the needle-free syringe 1 is in use (activated), and the pressurized injection liquid L can be injected without decelerating. Furthermore, by making the flow of the pressurized injection liquid L smooth, the pressure applied from inside to the container 1021 and the container holder 1022 can be reduced, improving the durability of the container unit 102.

[0050] <Application to a Needle-Type Syringe> As described above, the container unit 102 according to this embodiment may be applied to a needle-type syringe. For example, a configuration may be adopted in which an injection needle can be attached to the ejection port 1022b of the container unit 102 described above, and the injection liquid L is ejected through the injection needle. Note that the structure for fixing the injection needle to the nozzle portion 1022a may be a suitable structure, such as a screw system or a fitting system. When the container unit 102 is applied to a needle-type syringe, the pressurized injection liquid L flows through the nozzle flow path 1022f to the ejection port 1022b during use (activation) of the needle-type syringe and then flows into a flow path formed inside the injection needle. The injection liquid L thus supplied to the injection needle at high pressure is injected into a target area through the ejection port formed at the tip of the injection needle. Note that when the container unit 102 according to this embodiment is applied to a needle-type syringe, the plunger 104 may be manually driven to impart ejection energy to the injection liquid L contained in the storage space 10a. Even in a mode in which the container unit 102 according to this embodiment is applied to a needle syringe, the same technical effects as when applied to the needleless syringe 1 can be obtained.

[0051] Each feature disclosed herein may be combined with any other feature disclosed herein.

[0052] 1: Needle-free syringe 2: Filling device 20: Housing 30: Power cable 201: Switch 10: Syringe assembly 101: Actuator 101a: Body 102: Container unit 1021: Container 1022: Container holder 103: Attachment 104: Plunger

Claims

1. A container unit for a syringe, comprising: a container having a storage space for storing an injection liquid; and a container holder to which the container can be detachably attached, and which is used with the container attached when the syringe is in use, wherein the container holder has a nozzle portion having an ejection outlet for ejecting the injection liquid when the syringe is in use, and a nozzle flow path for directing the injection liquid from the storage space to the ejection outlet when the syringe is in use, wherein the container has a filling opening for directly filling the storage space with the injection liquid from the outside when the container is removed from the container holder, the filling opening being configured to communicate with the nozzle flow path when the container is attached to the container holder, and the opening cross-sectional area of ​​the filling opening is larger than the opening cross-sectional area of ​​the ejection outlet.

2. The container unit according to claim 1, wherein, when the container is attached to the container holder, a base end opening formed on the base end side of the nozzle flow channel is positioned opposite the filling opening.

3. A container unit as described in claim 2, configured such that, when the container is attached to the container holder, the base end opening of the container holder is included within a projection area of ​​the filling opening projected along the axial direction of the container unit.

4. The container unit according to claim 2, wherein, when the container is attached to the container holder, the base end opening and the filling opening are arranged coaxially.

5. The container unit according to claim 2, wherein the cross-sectional area of ​​the filling opening is equal to or larger than the cross-sectional area of ​​the base end opening.

6. A syringe comprising: a container unit according to any one of claims 1 to 5; and a housing configured to allow said container unit to be detachably attached thereto.

7. The syringe of claim 6, wherein the syringe is a needleless syringe.