Shooting device for needleless injector and needleless injection system

Abstract

The invention relates to a firing device for a needleless injector and a needleless injection system. The needleless injector includes an injection chamber housing and a piston assembly. The launching equipment comprises a power push rod, a power assembly and a launching assembly. The power push rod is configured to be connectable to the piston assembly. The power assembly comprises a power storage unit and a power output part, the power storage unit is constructed to be capable of storing or generating power used for driving the power output part to move, and the power output part is connected to the power push rod to drive the power push rod to move. The launching assembly comprises a launching rod and a control device, the launching rod is connected to the power push rod and can move synchronously with the power push rod, and the control device is configured to control the launching time of the launching rod in the state that the power output piece is driven by power. According to the scheme, the controllable power assembly is combined with the launching assembly, so that the injection force and the injection time are more controllable.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of medical devices, in particular the field of needle-free injection. More particularly, the present application relates to a launching device for a needle-free injector and a needle-free injection system. BACKGROUND

[0002] A needle-free injector is a medical device that does not use a needle, but instead uses high pressure to inject a liquid medicine through a micro-hole at the end of the device into the subcutaneous tissue of a patient, thereby eliminating the pain of needle insertion. Existing needle-free injectors rely on mechanical springs and other power sources to trigger injection. However, mechanical springs sometimes experience a decrease in thrust during the release process, resulting in insufficient consistency in injection force. In addition, existing needle-free injectors also have problems such as insufficient speed and accuracy in controlling the timing of injection.

[0003] Therefore, it is necessary to provide a launching device for a needle-free injector and a needle-free injection system to at least partially solve the above problems. SUMMARY

[0004] In one aspect, the present application provides a launching device for a needle-free injector, the needle-free injector comprising an injection chamber housing and a piston assembly, the injection chamber housing enclosing an injection chamber, a distal end of the injection chamber housing having an injection micro-hole, the piston assembly being movably disposed in the injection chamber, characterized in that the launching device is laterally disposed relative to the needle-free injector, the launching device comprising: a power push rod configured to be connectable to the piston assembly; a power assembly comprising a power storage unit and a power output, the power storage unit being configured to store or generate power for driving the power output to move, the power output being connected to the power push rod to drive the power push rod to move; and a launching assembly comprising a launching rod and a control device, the launching rod being connected to the power push rod and being capable of moving synchronously with the power push rod, wherein a central axis of the launching rod is non-coaxial with a central axis of the piston assembly, the control device being configured to control a launching time of the launching rod in a state where the power output is driven by power.

[0005] Preferably, the power storage unit comprises a gas storage device, the power output is configured as a power piston disposed in the gas storage device, one end of the gas storage device is provided with a gas interface for connecting to a high-pressure gas source, the power piston is capable of sliding in the gas storage device under the push of high-pressure gas, and the power piston is connected to the power push rod.

[0006] Preferably, the power storage unit comprises at least one pre-compressed drive spring, the power output comprises a drive block acted upon by the drive spring, and the drive block is connected to the power push rod.

[0007] Preferably, the power piston comprises a body portion and an extension column extending from the body portion towards a distal end, the extension column extending through the gas storage device and being connected to the power push rod.

[0008] Preferably, the control device comprises: a locking device comprising a stopper having a locked position and an unlocked position, the locked position being capable of restricting the movement of the firing rod, and the unlocked position being capable of allowing the movement of the firing rod; and a driving device comprising a driving member and a locking ring engaged with the driving member, the locking ring being capable of being driven by the driving member to move axially between a restraining position and a releasing position, the restraining position being capable of restraining the stopper in the locked position, and the releasing position being capable of releasing the stopper to move to the unlocked position.

[0009] Preferably, the locking device further comprises a stopper seat arranged around the firing rod, the firing rod being provided with a radially inwardly recessed groove, and the stopper seat being provided with a stopper flange at a position corresponding to the groove, when the stopper is in the locked position, a portion of the stopper is accommodated in the groove and the stopper is located at a proximal end of the stopper flange such that the stopper flange is capable of blocking the movement of the stopper and the firing rod towards the distal end.

[0010] Preferably, when the stopper is in the locked position, a projection of the stopper on a plane perpendicular to a central axis of the firing rod overlaps with a projection of the groove on the plane, and when the stopper is in the unlocked position, the projection of the stopper on the plane does not overlap with the projection of the groove on the plane.

[0011] Preferably, the locking ring is configured as a ring structure and has an inner wall portion and a recessed portion recessed radially outwardly relative to the inner wall portion, when the stopper is in the locked position, the inner wall portion covers the groove and the stopper flange and abuts against the stopper, and when the stopper is in the unlocked position, the recessed portion covers the groove and the stopper flange and a portion of the stopper is accommodated in the recessed portion.

[0012] Preferably, the side wall of the recess has a first inclined guide surface configured to push the stop portion radially outward when the firing rod moves toward the injection micro-hole until the stop portion leaves the recess.

[0013] Preferably, the side wall of the recess has a first inclined guide surface configured to push the stop portion radially outward when the firing rod moves toward the injection micro-hole until the stop portion leaves the recess.

[0014] Preferably, the firing device further comprises a mounting seat for mounting the driving member, the driving member is rotatably mounted on the mounting seat, and the driving member and the lock ring are respectively provided with thread portions matched with each other, the thread portions being capable of converting the rotational movement of the driving member into the linear movement of the lock ring.

[0015] Preferably, a first elastic return member is arranged between the mounting seat and the lock ring, the first elastic return member being capable of providing the lock ring with an elastic force for moving from the release position to the constraint position.

[0016] Preferably, the moving direction of the lock ring is parallel or coaxial with the moving direction of the power push rod.

[0017] Preferably, the power assembly further comprises a second elastic return member, the second elastic return member being arranged between the distal end of the main body portion and the inner wall of the gas storage device.

[0018] Preferably, the firing device further comprises a support shell configured to be connected to the injection cavity shell, and the gas storage device is fixedly connected with the support shell.

[0019] Another aspect of the present application provides a needle-free injection system, which comprises: a needle-free injector, which comprises: an injection cavity shell surrounding an injection cavity, a distal end of the injection cavity shell having an injection micro-hole communicating with the outside and the injection cavity; a piston assembly movably arranged in the injection cavity; and The firing device according to any one of the above, wherein the firing device is arranged laterally relative to the needle-free injector, and the central axis of the firing rod is different from the central axis of the piston assembly.

[0020] Preferably, the piston assembly comprises a piston and a piston rod connected to the proximal end of the piston, wherein a drug liquid channel is arranged in the piston rod and extends along the axial direction of the piston rod, and a piston inner channel is arranged on the piston and extends along a direction parallel to the axial direction, and the drug liquid channel and the piston inner channel are spaced apart in the radial direction about the axial direction.

[0021] Preferably, the needle-free injection system further comprises a drug storage assembly, which comprises a drug storage cavity shell, and a drug storage cavity is formed in the drug storage cavity shell, wherein the proximal end of the piston rod can be inserted into the drug storage cavity shell and extend into the drug storage cavity, so that the drug liquid in the drug storage cavity can enter the injection cavity through the drug liquid channel and the piston inner channel.

[0022] Preferably, the drug storage assembly further comprises a drug storage piston movably arranged in the drug storage cavity and a drug storage push rod connected to the drug storage piston, and the drug storage piston and the drug storage cavity shell jointly enclose the drug storage cavity.

[0023] Preferably, the inside of the piston rod is provided with a drug liquid tube, the drug liquid channel is formed in the drug liquid tube, and the proximal end of the drug liquid tube is formed with a needle-shaped structure capable of piercing the seal of the drug storage cavity shell.

[0024] Preferably, the needle-free injector further comprises a cap removably located at the front end of the injection cavity shell for closing the injection micropore.

[0025] The launching device for the needle-free injector and the needle-free injection system according to the present application have the following beneficial effects: 1. The needle-free injection system combines a controllable power assembly with a locking release structure, making the injection timing more controllable.

[0026] 2. By using high-pressure gas as a power source, active control of the initial injection pressure and pressure persistence can be achieved, not only maintaining consistent injection force, but also allowing flexible adjustment according to actual requirements.

[0027] 3. By replacing the metal needle with an injection micropore, the pain and psychological fear of patients during injection can be effectively eliminated, especially for patients who need long-term medication or are sensitive to needles.

[0028] 4. The locking device can achieve more reliable locking through the mechanical cooperation of the stopper and the groove on the launching rod, ensuring that the launching rod is firmly locked in the non-injection state to prevent accidental triggering, and accurately and reliably unlocking when injection is needed.

[0029] 5. The needleless injection system according to the present application is more compact in design, and the installation of the drug storage assembly, injection assembly and launching device is more convenient, which can improve the assembly efficiency and reduce the cost.

[0030] 6. The dose adjustment device converts the dose setting into an intuitive rotary positioning operation by setting the adjustment disc with different depth dose grooves cooperating with the adjustment column. This structure does not require additional tools, and the adjustment steps are simple, so that the user can quickly and accurately select and lock the predetermined dose, and the groove positioning provides clear visual feedback, effectively ensuring the accuracy and consistency of each injection dose, significantly improving the convenience of user operation and the controllability of treatment. BRIEF DESCRIPTION OF DRAWINGS

[0031] For better understanding of the above and other objects, features, advantages and functions of the present application, reference should be made to the preferred embodiments thereof illustrated in the accompanying drawings. The same or similar reference numerals in the drawings refer to the same or similar components. It should be understood by those skilled in the art that the drawings are intended to illustrate the preferred embodiments of the present application schematically, and have no limiting effect on the scope of the present application, and the various components in the drawings are not drawn to scale.

[0032] Figure 1 is a perspective view of a needleless injection system according to a preferred embodiment of the present application; Figure 2 is a front view of the needleless injection system shown in Figure 1 Figure 3 is a schematic view of the launching device of the needleless injection system shown in Figure 1 Figure 4 is a sectional view of a needleless injection system according to a preferred embodiment of the present application; Figure 5 is a schematic view of the needleless injector part of the needleless injection system shown in Figure 1 Figure 6 is a schematic view of the launching assembly part of the needleless injection system shown in Figure 1 Figure 7 is a perspective view of the power push rod of the needleless injection system shown in Figure 1 Figure 8 is a perspective view of the support housing of the needleless injection system shown in Figure 1 Figure 9 is a schematic view of the sealing assembly part of the needleless injection system shown in Figure 1 Figure 10 is a schematic view of the sealing assembly part of the needleless injection system shown in Figure 1 ​​​​​​​a perspective view of a dose dial of the needle-free injection system shown in Figure 11 To Figure 1 a perspective view of a dose shaft and a stop plate of the needle-free injection system shown in DETAILED DESCRIPTION

[0033] Hereinafter, the launching device and the needle-free injection system according to the preferred embodiment of the present application will be described in detail with reference to the accompanying drawings. The following given is only according to the preferred embodiment of the present application, and the person skilled in the art can think of other ways that can achieve the present application on the basis of the preferred embodiment, and other ways also fall within the scope of the present application.

[0034] The present application provides a launching device for a needle-free injector and a needle-free injection system comprising the launching device. First of all, it needs to be pointed out that the directional terms and positional terms mentioned in the present application should be understood as relative directions and relative positions, and the directional terms and positional terms mentioned in the present application can be understood with reference to the accompanying drawings. In the present application, the "proximal end" refers to the end of the needle-free injection system close to the hand of the operator, i.e. the end away from the injection micropore of the needle-free injection system, and the "distal end" refers to the end of the needle-free injection system away from the hand of the operator, i.e. the end close to the injection micropore. The "laterally arranged" means that two components or their axes are not arranged in series along the same straight line, but are arranged in a parallel and staggered manner, so that their main axes are parallel but not coincident.

[0035] Figures 1-2 A needle-free injection system according to one preferred embodiment of the present application is shown. The needle-free injection system of the present application can be quickly assembled and can quickly inject the liquid to be injected into the patient's body through the injection micropore in a very short time during the injection operation after assembly.

[0036] The needle-free injection system 100 comprises an injection assembly 110, a drug storage assembly 120, a sealing assembly and a launching device 130. The injection assembly 110, the drug storage assembly 120 and the sealing assembly can be collectively referred to as a needle-free injector, which will be described in detail below.

[0037] Injection assembly As Figures 1-4As shown, the injection assembly 110 is located at the front end of the needleless injection system 100. In a preferred embodiment, the injection assembly 110 comprises an injection chamber housing 111 and a piston assembly 112. The injection chamber housing 111 is generally cylindrical in shape, made of transparent or translucent glass, COC (cyclic olefin copolymer) or COP (cyclic olefin polymer) material, and has an interior forming an injection chamber for containing a medicament, and a front end having an extremely fine injection orifice 111a (typically about 0.1 mm in diameter). When an injection operation is intended, the front end of the injection chamber housing 111 can be pressed against the injection site, such as the skin of a patient, and when an injection operation is triggered (described below), the medicament in the injection chamber can be injected into the patient through the injection orifice 111a.

[0038] The piston assembly 112 is slidably disposed within the injection chamber. The piston assembly 112 comprises a piston 113 and a piston rod 114 fixedly connected to the rear end (i.e. the proximal end of the needleless injection system) of the piston 113. The piston 113 is in sealing sliding engagement with the inner wall of the injection chamber by means of a sealing ring (not shown in the figure). The piston rod 114 has a medicament passage 114a formed therein along the axial direction thereof. The piston 113 has a piston internal passage 113a formed therein extending in parallel to the axial direction. In the preferred embodiment shown, the piston internal passage 113a is arranged in parallel to the axial direction, but it is understood that in other embodiments not shown, the piston internal passage 113a can be arranged at an angle with respect to the axial direction.

[0039] In a preferred embodiment, the piston internal passage 113a and the medicament passage 114a are spaced apart in the radial direction with respect to the axial direction, i.e. they are not directly axially aligned and continuous. This design of the piston internal passage 113a and the medicament passage 114a forms a one-way flow structure, such that the medicament can only flow from the medicament storage chamber (described below) to the injection chamber, but not in the reverse direction. When the injection operation is performed, the injection orifice 111a can be sealed, and a negative pressure is generated in the injection chamber, which causes the piston 113 to displace or deform away from the piston rod 114, thereby causing the piston internal passage 113a to communicate with the medicament passage 114a, and thereby forming a medicament flow path from the medicament storage chamber to the injection chamber. When the injection operation is performed, the surface of the piston 113 inside the injection chamber is pressed by the pressure of the medicament, causing the joint surface of the piston 113 and the piston rod 114 to be pressed tightly, thereby ensuring that the medicament does not flow back into the piston rod 114.

[0040] Preferably, a separate medicine pipe 116 is arranged in the piston rod 114, the medicine pipe 116 is embedded in the piston rod 114, and the medicine pipe 116 has a medicine channel 114a formed therein. The medicine pipe 116 is preferably made of metal, and a proximal end of the medicine pipe 116 is processed into a needle-like structure, which can pierce a seal at an end of the medicine storage cavity shell 121 to establish communication between the medicine storage cavity and the medicine channel 114a. In other embodiments, the medicine channel 114a can also be formed by drilling a hole in the piston rod 114, in which case the needle-like structure can be configured as a separate structure having a flow channel in communication with the medicine channel 114a.

[0041] Preferably, the injection assembly 110 can further include a cap (not shown in the figure) removably covering a distal end of the injection cavity shell 111 for sealing and protecting the injection micropore 111a in a non-use state and a medicine suction state. In one embodiment, the cap can be provided with a cap protrusion, and the front end of the injection cavity shell 111 can be provided with a medicine tube groove, the cap protrusion and the medicine tube groove can be engaged with each other to facilitate installation of the cap on the injection cavity shell 111.

[0042] When the medicine suction operation is performed, the cap can be installed on the front end of the injection cavity shell 111, so that a negative pressure can be formed in the injection cavity to enable the medicine in the medicine storage cavity to be sucked into the injection cavity through the medicine channel and the piston inner channel. When the injection operation is performed, the cap can be removed and the piston assembly can be controlled to move forward relative to the injection cavity shell 111 to eject the medicine in the injection cavity through the injection micropore 111a.

[0043] As shown in Figure 5 , the proximal end (rear end) of the piston rod 114 is further provided with a cylindrical barrier 115, and the needle-like structure of the medicine pipe 116 extends into the barrier 115, which can be connected and positioned with the sealing assembly and the power push rod 132 (described below) of the launching device 130.

[0044] Medicament storage assembly The medicine storage assembly 120 is used to pre-store the medicine to be injected, and the medicine storage assembly 120 is coaxially arranged with the injection assembly 110. As shown in Figure 4 and Figure 5 , the medicine storage assembly 120 includes a medicine storage cavity shell 121, a medicine storage piston 122, and a medicine storage push rod 123.

[0045] An elongated portion 124 is formed at the distal end of the drug storage cavity housing 121, which is close to the injection assembly 110. The distal end of the elongated portion 124 is closed by a pierceable seal (e.g. a rubber plug). The elongated portion 124 is capable of being docked and clamped by a sealing assembly (described below). A drug storage piston 122 is slidably disposed in the drug storage cavity, and the outer periphery of the drug storage piston 122 is in sealing contact with the inner wall of the drug storage cavity housing 121. The drug storage piston 122 and the drug storage cavity housing 121 together define a closed drug storage cavity. A drug storage push rod 123 is connected to the proximal end of the drug storage piston 122, and when the drug storage push rod 123 is moved distally, the drug storage push rod 123 can drive the drug storage piston 122 to move, thereby enabling the drug liquid to be discharged through the pierceable seal.

[0046] Sealing assembly In order to achieve a sterile sealed connection between the drug storage assembly 120 and the injection assembly 110, the needle-free injection system 100 further comprises a sealing assembly. As shown in Figure 5 and Figure 9 , the sealing assembly comprises a mounting portion 141 and an elastic member 142.

[0047] The mounting portion 141 is capable of being fixedly installed inside the containment portion 115 of the piston rod 114. The mounting portion 141 is generally formed in a U-shaped structure, and has an accommodation space inside. An axial first through hole 143 is formed in the bottom wall of the mounting portion 141, and the first through hole 143 is in communication with the accommodation space. The elastic member 142 is installed in the accommodation space, and the elastic member 142 is preferably made of an elastic material such as silicone. The elastic member 142 is provided with a second through hole 144 in the center. In the assembled state of the drug storage assembly 120, the sealing assembly, and the injection assembly 110, the elongated portion 124 of the drug storage assembly 120 is inserted into the mounting portion 141, and the seal at the distal end of the elongated portion 124 is tightly pressed against the proximal end surface of the elastic member 142, thereby forming a clamping seal. The drug liquid tube 116 pierces the seal of the drug storage cavity housing 121 after extending through the first through hole 143 and the second through hole 144. Preferably, the diameter of the second through hole 144 of the elastic member 142 is slightly smaller than the outer diameter of the drug liquid tube 116 to ensure the seal after piercing.

[0048] During assembly, the mounting portion 141 of the sealing assembly is first fixedly installed inside the retaining portion 115 of the piston rod 114 of the injection assembly 110, and the elastic member 142 is installed in the mounting portion 141. Then, the extended portion 124 of the drug storage assembly 120 is aligned and pushed into the mounting portion 141 already installed on the injection assembly, and the sealing member at the end of the extended portion 124 presses against the elastic member 142. During this process, the needle-like structure of the drug liquid tube 116 inside the piston rod 114 passes sequentially through the second through hole 144 of the elastic member 142 and the sealing member at the end of the extended portion 124, extending into the drug storage chamber. Simultaneously, the extended portion 124 is secured in the mounting portion 141, and its sealing member presses against the elastic member 142, forming a reliable sealing connection.

[0049] Firing device The launching device 130 is the core of the needle-free injection system for control, power, and dosage adjustment. The launching device 130 is positioned laterally relative to the needle-free injector (i.e., the injection assembly, drug reservoir, and sealing assembly); that is, the launching device 130 is not coaxially aligned with the needle-free injector, but rather positioned to one side of it. This lateral connection ensures that the axis of the launching device is parallel to the axis of the needle-free injector, forming a compact overall structure. The launching device 130 mainly includes a support housing 131, a power push rod 132, a launching assembly 160, a power assembly 170, and a dosage adjustment device 180.

[0050] like Figure 1 , Figure 4 and Figure 8 As shown, the support housing 131 constitutes the main structural frame of the launching device 130. The support housing 131 is laterally disposed relative to the injection cavity housing 111, and its distal end can be connected to the injection cavity housing 111 of the injection assembly 110. In one embodiment, the support housing 131 includes a support body 131a and a first fitting portion 131b disposed at the distal end of the support body 131a. The support body 131a is constructed as an elongated structure with a generally arc-shaped cross-section, and the first fitting portion 131b is generally constructed as an annular structure, which is arranged perpendicularly to the support body 131a. A first fitting hole 131c is provided in the first fitting portion 131b, and the proximal end of the injection cavity housing 111 can be tightly fitted into the first fitting hole 131c to achieve a stable connection. Preferably, the proximal end of the injection cavity housing 111 can also be detached from the first fitting hole 131c.

[0051] In the mounted state, the power push rod 132 is disposed within the arc-shaped contour of the support housing 131 and is axially movable relative to the support housing 131. The power push rod 132 is disposed laterally relative to the support housing 131, and is also disposed laterally relative to the injection cavity housing 111, and the distal end of the power push rod 132 is connectable to the piston assembly 112 and can drive the piston assembly 112 to move together. As shown in Figure 4 and Figure 7 The power push rod 132 includes a push rod body 132a and a second sleeving portion 132b disposed at the distal end of the push rod body 132a. The push rod body 132a is configured as an elongated structure, and the cross section thereof is substantially arc-shaped. The second sleeving portion 132b is substantially configured as a ring-shaped structure, and is arranged perpendicularly relative to the push rod body 132a. The second sleeving portion 132b is provided with a second sleeving hole 132c. The surrounding portion 115 at the proximal end of the piston rod 114 can be sleeved in the second sleeving hole 132c, thereby achieving linkage. Preferably, the piston rod 114 can also be detached from the second sleeving hole 132c. As shown in Figure 4 The power push rod 132 further includes a boss portion 133 disposed on the push rod body 132a and extending laterally relative to the push rod body 132a. In the assembled state of the needle-free injection system 100, the boss portion 133 can abut against the proximal end of the drug storage cavity housing 121 of the drug storage assembly 120, thereby serving as axial positioning and supporting.

[0052] The power push rod 132 further includes an extension flange 187 disposed at the proximal end of the push rod body 132a, which is arranged perpendicularly relative to the push rod body 132a, and is used for mounting the dose adjustment column 182 of the dose adjustment device 180 (described below).

[0053] The launch assembly 160 can control the launch timing of the power push rod 132, thereby controlling the injection time. That is, when the pressure inside the gas storage device 171 (described below) increases, the drug liquid in the injection cavity cannot be directly pushed out through the power push rod 132, but the launch time of the power push rod 132 is controlled by the launch assembly 160. The structure of the launch assembly 160 will be described in detail below. As shown in Figure 4 and Figure 6 The launch assembly 160 includes a launch rod 134, a locking device 135, and a driving device 137, which can also be collectively referred to as a "control device", which can control the launch time of the launch rod 134.

[0054] As shown in Figure 6As shown, the launching rod 134 extends substantially parallel to the power push rod 132, with its distal end connected to the power push rod 132 and capable of synchronous movement with the power push rod 132. Exemplarily, the launching rod 134 can be connected to the power push rod 132 by screwing or clamping, etc. Since the launching device 130 is arranged on one side of the needleless injector, the central axis of the launching rod 134 is not coaxial with the central axis of the piston assembly. The launching rod 134 is provided with a radially inwardly recessed groove 152, which can be configured as an annular groove or a non-annular arc-shaped groove. The proximal end inner surface of the side wall of the groove 152 is machined into a first inclined guide surface 156. When the launching rod 134 is released to move at high speed in the distal direction, the first guide surface 156 will contact the stop portion 136 and use its inclined surface to smoothly push the stop portion 136 radially outward out of the groove 152.

[0055] The locking device 135 is used to mechanically lock or release the launching rod 134. The locking device 135 includes a stop seat 151 fixedly connected to the support housing 131 and a stop portion 136 radially movably arranged. The stop seat 151 is arranged around the launching rod 134 on its outer side. At an axial position corresponding to the groove 152 on the launching rod 134, the stop seat 151 is provided with an annular stop flange 153 and a radial opening formed thereby, which is axially aligned with the groove 152. The stop portion 136 can be configured as a steel ball or other spherical structure, which can be accommodated in the groove 152 of the launching rod 134 and the corresponding radial opening on the stop seat 151. When the stop portion 136 is in the locked position, it is partially accommodated in the groove 152 under external constraint, and its entirety is located at the proximal end of the stop flange 153. At this time, the stop flange 153 can block the stop portion 136 from moving distally, and since the stop portion 136 is stuck in the groove 152, the launching rod 134 is firmly locked. From the projection relationship, at this time, the projection of the stop portion 136 on a plane perpendicular to the axis of the launching rod 134 has an overlapping portion with the projection of the groove 152 on the plane. When the stop portion 136 is in the unlocked position, it moves radially outward and completely escapes from the groove 152, and its projection no longer overlaps with the projection of the groove 152, so that the launching rod 134 can be released. When the launching rod 134 is released, it can advance at high speed in the injection cavity together with the power push rod 132 under the action of power, thereby extruding the liquid medicine to be ejected from the injection micro-holes 111a.

[0056] The driving device 137 can control the stop portion 136 to switch between the locked position and the unlocked position. As shown in FIG. 2, the driving device 137 can be configured as a solenoid, which is arranged on the support housing 131 and has a plunger 138. The plunger 138 is arranged in the stop seat 151 and is capable of moving radially in the stop seat 151. The plunger 138 is provided with a radially outwardly protruding stop portion 136. When the solenoid is not energized, the plunger 138 is in the locked position, and the stop portion 136 is accommodated in the groove 152 of the launching rod 134. When the solenoid is energized, the plunger 138 is in the unlocked position, and the stop portion 136 moves radially outward and escapes from the groove 152. Figure 6As shown, the drive device 137 comprises a motor 138 as a driving member and a lock ring 139 which can be driven by the motor 138. The lock ring 139 is configured as a ring sleeve structure which is sleeved outside the stop seat 151 and can move relative to the stop seat 151. Preferably, the moving direction of the lock ring 139 is parallel or coaxial with the moving direction of the power push rod 132, so that the structure of the needle-free injection system is more compact. The inner wall of the lock ring 139 comprises an inner wall portion 154 with a smaller inner diameter and a recessed portion 155 which is recessed radially outward relative to the inner wall portion 154. The proximal inner side of the side wall of the recessed portion 155 is machined into an inclined second guide surface 157. When the lock ring 139 moves axially to the constraint position under the driving of the motor 138, the inner wall portion 154 covers the area where the recess 152 and the stop flange 153 are located. The inner surface of the inner wall portion 154 abuts and constrains the stop portion 136 from the radial outside, forcing it to remain in the locked position. When the lock ring 139 moves to the release position, the recessed portion 155 covers the area where the recess 152 and the stop flange 153 are located. The recessed portion 155 provides a larger radial space, which can release the radial constraint on the stop portion 136, so that the stop portion 136 can move radially outward into the recessed portion 155 under the extrusion of the first guide surface 156 when the launch rod moves distally to reach the unlocked position. When the lock ring 139 returns from the release position to the constraint position, the second guide surface 157 will contact the stop portion 136 located in the recessed portion 155 during the movement, and by the inclined surface, the stop portion 136 is pushed radially inward until the stop portion 136 exits the recessed portion 155 and reenters the recess 152.

[0057] The launch device 130 further comprises a motor mounting seat 159 arranged in the support housing 131, and the motor 138 is fixedly mounted on the motor mounting seat 159. In a preferred embodiment, the motor 138 drives the lock ring 139 to move through threaded transmission. The motor 138 is provided with a motor head 158, and the motor head 158 is provided with an outer thread with a predetermined pitch. The inner wall of the lock ring 139 is provided with an inner thread with a predetermined pitch matched with the outer thread. When the motor 138 drives the motor head 158 to rotate, the rotational movement of the motor head 158 can be converted into the axial linear movement of the lock ring 139 through the thread pair formed by the outer thread and the inner thread. For example, when it is intended to drive the lock ring 139 to move from the constraint position to the release position, the motor head 158 can be driven to rotate forward, thereby driving the lock ring 139 to move axially.

[0058] When the lock ring 139 is intended to be driven back from the release position to the constraint position, in a preferred embodiment, a first elastic return member 161 (such as a compression spring) can be arranged between the motor mount 159 and the lock ring 139. The first elastic return member 161 can provide an elastic return force to the lock ring 139 for moving from the release position to the constraint position. When the motor 138 drives the lock ring 139 to move from the constraint position to the release position, the relative distance between the lock ring 139 and the motor mount 159 decreases, and the first elastic return member 161 is gradually compressed to store elastic potential energy. When the lock ring 139 reaches the release position and remains, the spring is in the maximum compression state. Once the driving force of the motor 138 is withdrawn, the elastic potential energy stored by the first elastic return member 161 pushes the lock ring 139 to automatically move back from the release position to the constraint position, achieving automatic return.

[0059] As another return method, the automatic return of the lock ring 139 can also be directly controlled by the rotation direction of the motor head 158. For example, when the motor head 158 rotates forward, the lock ring 139 can be driven to move from the constraint position to the release position through threaded transmission; and when the lock ring 139 needs to be returned to the constraint position, the motor head 158 can be reversely rotated to drive the lock ring 139 to move back from the release position to the constraint position.

[0060] In a preferred embodiment, the motor 138 of the driving device 137 can be driven and controlled by an integrated control circuit. The control circuit is activated in response to user operation, specifically, a physical button or touch panel (not shown in the figure) arranged outside the support housing 131 and convenient to operate. When the user presses the button or touches the corresponding interface, an electrical signal is generated, and the control circuit receives the signal to accurately drive the motor 138 to operate according to the preset program, thereby completing the position switching of the lock ring 139 and achieving instant and reliable control of the injection timing. This external button control mode provides an intuitive and convenient trigger operation interface for the user, further improving the ease of use and operation experience of the system.

[0061] The transmission device can achieve fast response and start when the injection operation is intended to be performed by using a motor as the main driving member, so that the needle-free injection system can complete the injection process in a very short time, not only effectively controlling the timing of injection but also reducing the operation delay. Moreover, this scheme can also enable the needle-free injection system to efficiently complete continuous multiple injections, greatly improving the injection efficiency and reducing the user's use burden.

[0062] Power assembly The power assembly 170 can provide initial driving force for the injection operation. The power assembly includes a power storage unit capable of storing or generating power for driving the power output to move, and a power output connected to the power push rod to drive the power push rod to move.

[0063] In the preferred embodiment shown, the power assembly 170 is driven in a pneumatic manner. As shown, the power storage unit includes a gas storage device 171, and the power output is configured as a power piston 173. The gas storage device 171 is generally configured as a cylindrical structure, which is fixedly connected to the support housing 131, for example, by being integrally formed or by being bolted. One end (proximal end) of the gas storage device 171 is provided with a gas interface 172 for connecting to an external high-pressure gas source (such as a gas pump or a compressed gas source). The power piston 173 is disposed in the gas storage device 171 and can slide in the gas storage device 171 under the push of high-pressure gas towards the distal end of the injection micro-hole 111a. Figure 4

[0064] The power piston 173 includes a disc-shaped main body 174 and an extension column 175 extending from the main body 174 towards the distal end (injection direction). The main body 174 is in sealing sliding fit with the inner wall of the gas storage device 171. The extension column 175 extends through the distal end wall of the gas storage device 171, extends into the support housing 131 and is connected to the proximal end of the power push rod 132. Exemplarily, the extension column 175 can be connected to the power push rod 132 by screw connection or snap connection, etc. A second elastic return member 176 (such as a compression spring) is also provided in the gas storage device 171, which is disposed between the distal end face of the main body 174 of the power piston 173 and the inner wall of the gas storage device 171.

[0065] ​When the injection operation is performed, the high-pressure gas is filled into the gas storage device 171 through the gas interface 172 instantaneously, and acts on the main body part 174 of the power piston 173 to generate a strong thrust force, which pushes the power piston 173, the power push rod 132, the launching rod 134 and the piston assembly 112 together to move towards the distal end of the injection micro-hole 111a, at this time, the second elastic reset member 176 is in a compressed state. When the injection is completed, the high-pressure gas source can be removed, the gas interface 172 is connected with the atmosphere, and the second elastic reset member 176 is reset, so as to push the power piston 173 towards the proximal end away from the injection micro-hole 111a, and drive the power push rod 132, the launching rod 134 and the piston assembly 112 to move towards the proximal end. At this time, if the injection micro-hole 111a at the front end of the injection cavity shell 111 is closed by the cap part, a negative pressure will be formed in the injection cavity with the retraction of the piston 113, which is transmitted to the medicine storage cavity, so that the medicine in the medicine storage cavity is sucked into the injection cavity through the medicine passage 114a of the medicine liquid pipe 116 and the piston inner passage 113a, and the medicine taking (i.e. medicine supplementing) process is completed.

[0066] By using high-pressure gas as the power source, the active control of the initial injection pressure and the pressure persistence can be realized, which not only keeps the injection force consistent, but also can be flexibly adjusted according to the actual requirements. In addition, the needle-free injection system combines the controllable power assembly with the locking and releasing structure, so that the injection timing is more controllable.

[0067] In other embodiments, the power storage unit can adopt a mechanical structure with a spring as the power source. For example, the power storage unit includes at least one pre-compressed driving spring, and the power output member includes a driving block acted on by the driving spring to be able to generate movement, and the driving block is connected to the power push rod.

[0068] Dose adjustment means The dose adjusting device 180 is used to pre-set the injection dose. As shown in FIG. 1, the dose adjusting device 180 includes a dose adjusting knob 181, a dose adjusting screw 182 and a dose adjusting spring 183. The dose adjusting knob 181 is connected with the dose adjusting screw 182, and the dose adjusting screw 182 is connected with the dose adjusting spring 183. Figure 4 、 Figure 10 and Figure 11As shown, the dose adjustment device 180 mainly comprises a dose adjustment disc 181 and a dose adjustment column 182. The dose adjustment disc 181 is rotatably connected to the support housing 131 by a support shaft 185. In one embodiment, the support shaft 185 is fixedly connected with the dose adjustment disc 181 and extends through the center of the dose adjustment disc 181. Exemplarily, the support shaft 185 can be fixedly connected with the dose adjustment disc 181 in a threaded connection or an interference fit manner. In a preferred embodiment, part of the disc body structure of the dose adjustment disc 181 is designed to extend to the outside of the support housing 131. This extended part facilitates the user to directly operate it. Without the need of tools, the user can directly rotate the exposed disc body structure with fingers, thereby driving the entire dose adjustment disc 181 to rotate on the support housing 131 to achieve dose selection.

[0069] As shown, Figure 4 The support housing 131 is further provided with a fixing seat 184, and the distal end of the support shaft 185 is rotatably inserted into the bearing or shaft hole of the fixing seat 184. The distal end of the support shaft 185 is further fixedly connected with a limiting plate 186, which cooperates with the fixing seat 184 and abuts against the distal end face of the fixing seat 184 to axially limit the dose adjustment disc 181.

[0070] A plurality of dose grooves 183 are uniformly and spacedly formed on the dose adjustment disc 181 around the center thereof. The plurality of dose grooves 183 are configured as blind grooves extending radially on the dose adjustment disc 181, and the depths of the plurality of dose grooves 183 are different from each other, each depth corresponding to a preset injection dose.

[0071] The dose adjustment column 182 is fixedly installed on the extended flange 187 of the power push rod 132 and extends towards the distal end. Before starting the injection operation, the distal end of the dose adjustment column 182 can be aligned with a selected dose groove 183 by rotating the dose adjustment disc 181. The depth of the dose groove 183 determines the limit position of the distal movement of the dose adjustment column 182, the power push rod 132 and the power piston 173 connected therewith, i.e., sets the "pre-travel" of the power push rod 132 before launching, thereby setting the effective stroke of the piston assembly in the injection chamber and controlling the discharge amount of the liquid medicine.

[0072] In a preferred embodiment, clear scale marks corresponding to each dose groove 183 can be engraved or marked on the outer surface of the disc body of the dose adjustment disc 181. When the user rotates the dose adjustment disc 181, the scale value corresponding to the currently selected dose groove 183 can be directly observed, thereby quickly and accurately completing dose setting. This exposed design with visual scale feedback greatly enhances the intuitiveness, convenience and accuracy of the dose adjustment operation, enabling the user to easily and reliably preset the required injection dose.

[0073] The assembly and operation of the needle-free injection system 100 will be described below.

[0074] Assembly: First, the injection assembly and the launching device can be assembled together. Specifically, the proximal end of the injection cavity housing 111 is aligned and fitted into the first fitting hole 131c of the support housing 131 until a firm connection is achieved. The second fitting part 132b of the power push rod 132 is fitted close to the assembled piston assembly 112, and the blocking part 115 at the proximal end of the piston rod 114 is aligned and fitted into the second fitting hole 132c. This connection allows the power push rod 132 to be linked with the piston assembly 112.

[0075] Then, the sealing assembly and the drug storage assembly can be assembled. Specifically, the mounting part 141 of the sealing assembly can be fixedly mounted inside the blocking part 115 of the piston rod 114 of the injection assembly 110, and the elastic member 142 is mounted in place in the mounting part 141. Subsequently, the elongated part 124 of the drug storage assembly 120 is aligned and pushed into the mounting part 141 that has been mounted on the injection assembly. In this process, the needle-like structure of the liquid tube 116 in the piston rod 114 successively passes through the second through hole 144 of the elastic member 142 and the sealing member at the end of the elongated part 124, and extends into the drug storage cavity. At the same time, the elongated part 124 is clamped in the mounting part 141, and the sealing member at the end thereof presses the elastic member 142, forming a reliable sealing connection. At this time, the boss part 133 on the power push rod 132 should abut against the proximal end surface of the drug storage cavity housing 121 of the drug storage assembly 120. The boss part 133 provides axial support for the entire drug storage assembly 120, ensuring the stability of the connection. At this point, the launching device 130 and the needle-free injector are assembled, and this modular design greatly facilitates the rapid assembly before use and the maintenance and component replacement after use.

[0076] Dose setting: Before the injection operation, the user can observe the scale marks on the dose adjustment disc 181 and manually rotate the dose adjustment disc 181, so that the distal end of the dose adjustment column 182 is aligned with the dose groove 183 with the corresponding scale mark, thereby setting the effective stroke of the power piston 173.

[0077] Triggering injection: The high-pressure gas source is connected to the gas interface 172, and the user can issue an injection instruction, for example, by pressing the start button on the device housing. The control circuit then drives the motor 138 to rotate rapidly (for example, in the forward direction), and the locking ring 139 is instantaneously pulled to the release position through threaded transmission. The recessed part 155 of the locking ring 139 moves to the stop part 136, removing the radial constraint thereon, and the stop part 136 moves outward to disengage from the groove 152, and the launching rod 134 is unlocked. The high-pressure gas pushes the power piston 173 to move at high speed, thereby driving the power push rod 132 and the piston assembly 112 to move at high speed, and the liquid in the injection cavity is ejected from the injection micro-hole 111a at extremely high pressure.

[0078] System reset: After injection is completed, the high-pressure gas source can be removed from the gas interface 172, and the gas interface 172 is connected to the atmosphere, thereby releasing the residual pressure in the gas storage device 171. Under the action of the restoring force of the second elastic reset member 176, the power piston 173 begins to move to the proximal end (right) to reset, thereby driving the power push rod 132, the launch rod 134, and the piston assembly 112 connected thereto to move to the proximal end.

[0079] At this time, if the injection micro-hole 111a at the front end of the injection cavity shell 111 is closed by the cap, a negative pressure will be formed in the injection cavity as the piston 113 retracts, and the negative pressure is transmitted to the drug storage cavity. The drug liquid in the drug storage cavity can be sucked in through the drug liquid passage 114a of the drug liquid pipe 116 and enter the injection cavity through the piston inner passage 113a, thereby completing the drug taking (i.e., supplementing the drug liquid) process.

[0080] At the same time, the lock ring 139 automatically returns to the constraint position from the release position under the action of the first elastic reset member 161. In the movement of the lock ring 139, the second guide surface 157 of the recessed portion 155 contacts and forces the stop portion 136 to move radially inward. When the power piston 173 is completely restored to the original position and the lock ring 139 is accurately returned to the constraint position, the inner wall portion 154 will press the stop portion 136 into the groove 152 of the launch rod 134 again, and the needle-free injection system 100 returns to the locked state, ready for the next injection. Moreover, the dose adjustment column 182 is also reset to the right end initial position with the power push rod 132.

[0081] Based on the above-described needle-free injection system of the present application, efficient, rapid, and automatic pneumatic continuous injection can be achieved. This feature is particularly suitable for treatment scenarios that require continuous small-dose administration, such as intensive insulin therapy or medical beauty injection, etc.

[0082] In use, when the user assembles the various components together and completes the first dose setting, the treatment process can be simplified to repeatedly pressing the same external button. Each time the button is pressed, the system completes an accurate injection. After the injection is completed, when the high-pressure gas is released and the system is connected to the atmosphere, the piston assembly is automatically retracted and reset under the action of the second elastic reset member, and simultaneously completes the "drug sucking" process of extracting the required drug liquid from the drug storage cavity. Subsequently, only the button needs to be pressed again to trigger the next injection. The above process can be continuously and rapidly performed until the drug liquid in the drug storage cavity is completely injected. The entire process greatly reduces the physical burden of frequent user operations, converts the cumbersome process of traditional manual injection into a simple repeated button action, and significantly improves the treatment efficiency.

[0083] It should be noted that the medicine, liquid medicine and other medicine injection are taken as examples to describe the concept of the present disclosure, but this is only an example and is not limited. The injection can be other various types, such as physiological saline, glucose, etc., as long as the injection can be injected into the human body by the needleless injector of the present disclosure, which falls within the protection scope of the present disclosure.

[0084] The cooperation features such as the protrusions, the grooves, the flanges, the buckles, etc. in each cooperation structure group provided in the above embodiments can be structures extending in the circumferential direction and arranged intermittently, or can be structures arranged continuously in the circumferential direction, and the injection system can be correspondingly adjusted in structure.

[0085] In addition, although the embodiments of the present disclosure take the needleless injector as an example, the structure of the present disclosure can also be applied to the needle injector.

[0086] The above description of various embodiments of the present disclosure is provided to one of ordinary skill in the relevant art for descriptive purposes. The present disclosure is not intended to be exclusive or limited to a single disclosed embodiment. As such, one of ordinary skill in the art will appreciate or be reasonably capable of determining variations and alternatives of the present disclosure as taught above. Therefore, although some alternative embodiments are specifically described, one of ordinary skill in the art will appreciate or be reasonably capable of developing other embodiments. The present disclosure is intended to include all alternatives, modifications and variations of the present disclosure described herein, as well as other embodiments falling within the spirit and scope of the present disclosure described above.

Claims

1. A firing device (130) for a needle-free injector, the needle-free injector comprising an injection chamber housing (111) and a piston assembly (112), the injection chamber housing (111) forming an injection chamber, the distal end of the injection chamber housing (111) having an injection micro-orifice (111a), and the piston assembly (112) being movably disposed within the injection chamber, characterized in that, The launching device (130) is disposed laterally relative to the needleless injector, and the launching device (130) includes: A power push rod (132) is configured to be connected to the piston assembly (112). A power assembly (170) comprising a power storage unit and a power output element, the power storage unit being configured to store or generate power for driving the power output element to move, the power output element being connected to the power push rod (132) to drive the power push rod (132) to move; and The launching assembly (160) includes a launching rod (134) and a control device. The launching rod (134) is connected to the power push rod (132) and is capable of moving synchronously with the power push rod (132). The central axis of the launching rod is not coaxial with the central axis of the piston assembly. The control device is configured to control the launching time of the launching rod (134) when the power output element is powered.

2. The launching device (130) according to claim 1, characterized in that, The power storage unit includes a gas storage device (171), and the power output component is configured as a power piston (173) disposed in the gas storage device (171). One end of the gas storage device (171) is provided with a gas interface (172), which is used to connect to a high-pressure gas source. The power piston (173) can slide in the gas storage device (171) under the push of the high-pressure gas. The power piston (173) is connected to the power push rod (132).

3. The launching device (130) according to claim 1, characterized in that, The power storage unit includes at least one pre-compressed drive spring, and the power output component includes a drive block acted upon by the drive spring, the drive block being connected to the power push rod.

4. The launching device (130) according to claim 2, characterized in that, The power piston (173) includes a main body (174) and an extension column (175) extending from the main body (174) toward a distal end, the extension column (175) extending through the gas storage device (171) and connected to the power push rod (132).

5. The launching device (130) according to claim 1, characterized in that, The control device includes: A locking device (135) includes a stop (136) having a locked position and an unlocked position. When the stop (136) is in the locked position, it restricts the movement of the launching rod (134); when the stop (136) is in the unlocked position, it allows the movement of the launching rod (134). A drive device (137) includes a drive member and a locking ring (139) engaged with the drive member. The locking ring (139) can be driven by the drive member to move axially between a constrained position and a released position. When the locking ring (139) is in the constrained position, it can constrain the stop (136) in the locked position. When the locking ring (139) is in the released position, it can release the constraint on the stop (136) so that the stop (136) can move to the unlocked position.

6. The launching device (130) according to claim 5, characterized in that, The locking device (135) further includes a stop seat (151) which is arranged around the launching rod (134). The launching rod (134) is provided with a radially inward recessed groove (152), and a stop flange (153) is provided on the stop seat (151) at a position corresponding to the groove (152). When the stop part (136) is in the locked position, a portion of the stop part (136) is accommodated in the groove (152), and the stop part (136) is located at the proximal end of the stop flange (153) so that the stop flange (153) can prevent the stop part (136) and the launching rod (134) from moving toward the distal end.

7. The launching device (130) according to claim 6, characterized in that, When the stop (136) is in the locked position, the projection of the stop (136) on the plane perpendicular to the central axis of the launch rod (134) overlaps with the projection of the groove (152) on the plane. When the stop (136) is in the unlocked position, the projection of the stop (136) on the plane does not overlap with the projection of the groove (152) on the plane.

8. The launching device (130) according to claim 6, characterized in that, The locking ring (139) is constructed as a ring structure and has an inner wall portion (154) and a recessed portion (155) that is radially recessed outward relative to the inner wall portion (154). When the stop portion (136) is in the locked position, the inner wall portion (154) covers the groove (152) and the stop flange (153) and abuts against the stop portion (136). When the stop portion (136) is in the unlocked position, the recessed portion (155) covers the groove (152) and the stop flange (153) and a portion of the stop portion (136) is accommodated in the recessed portion (155).

9. The launching device (130) according to claim 6, characterized in that, The sidewall of the groove (152) has an inclined first guide surface (156) configured to push the stop (136) radially outward when the launch rod (134) moves toward the injection micro-hole (111a) until the stop (136) leaves the groove (152).

10. The launching device (130) according to claim 8, characterized in that, The sidewall of the recessed portion (155) has an inclined second guide surface (157) configured to push the stop (136) radially inward as the locking ring (139) moves from the release position toward the restraint position until the stop (136) leaves the recessed portion (155).

11. The launching device (130) according to claim 5, characterized in that, The launching device (130) also includes a mounting base (159) for mounting the drive member, the drive member being rotatably mounted on the mounting base (159), and the drive member and the locking ring (139) are respectively provided with threaded portions that cooperate with each other, the threaded portions being able to convert the rotational motion of the drive member into the linear motion of the locking ring (139).

12. The launching device (130) according to claim 5, characterized in that, A first elastic reset member (161) is provided between the mounting base (159) and the locking ring (139), the first elastic reset member (161) being able to provide the locking ring (139) with an elastic force that moves it from the release position to the restraint position.

13. The launching device (130) according to claim 5, characterized in that, The direction of movement of the locking ring (139) is parallel or coaxial with the direction of movement of the power push rod (132).

14. The launching device (130) according to claim 4, characterized in that, The power assembly (170) also includes a second elastic reset member (176), which is disposed between the distal end of the main body (174) and the inner wall of the gas storage device (171).

15. The launching device (130) according to claim 1, characterized in that, The launching device (130) also includes a support housing (131) configured to be connected to the injection chamber housing (111), and the gas storage device (171) is fixedly connected to the support housing (131).

16. A needle-free injection system (100), characterized in that, include: Needle-free injector, the needle-free injector comprising: An injection chamber housing (111) surrounds an injection chamber, and the distal end of the injection chamber housing (111) has an injection micropore (111a) that connects to the outside and the injection chamber. The piston assembly (112) is movably disposed in the injection chamber; as well as The launching device (130) according to any one of claims 1-15, wherein the launching device is disposed laterally relative to the needleless injector, and the central axis of the launching rod is not coaxial with the central axis of the piston assembly.

17. The needle-free injection system (100) according to claim 16, characterized in that, The piston assembly (112) includes a piston (113) and a piston rod (114) connected to the proximal end of the piston (113). The piston rod (114) has a liquid medicine channel (114a) that extends along the axial direction of the piston rod (114). The piston (113) has an inner piston channel (113a) that extends in a direction parallel to the axial direction. There is a gap between the inner piston channel (113a) and the liquid medicine channel (114a) in the radial direction about the axial direction.

18. The needle-free injection system (100) according to claim 17, characterized in that, The needle-free injection system (100) further includes a drug storage assembly (120), which includes a drug storage chamber housing (121) forming a drug storage chamber. The proximal end of the piston rod (114) can be inserted into the drug storage chamber housing (121) and extend into the drug storage chamber, so that the liquid medicine in the drug storage chamber can enter the injection chamber through the liquid medicine channel (114a) and the piston internal channel (113a).

19. The needle-free injection system (100) according to claim 18, characterized in that, The drug storage assembly (120) further includes a drug storage piston (122) movably disposed in the drug storage cavity and a drug storage push rod (123) connected to the drug storage piston (122). The drug storage piston (122) and the drug storage cavity housing (121) together form the drug storage cavity.

20. The needle-free injection system (100) according to claim 18, characterized in that, The piston rod (114) is provided with a liquid tube (116) inside, and the liquid channel (114a) is formed in the liquid tube (116). A needle-like structure is formed at the proximal end of the liquid tube (116), and the needle-like structure can pierce the sealing part of the storage chamber shell (121).

21. The needle-free injection system (100) according to claim 16, characterized in that, The needleless injector also includes a cap removably located at the front end of the injection chamber housing (111) for closing the injection micro-orifice (111a).

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