Needle-free injector capable of multiple injections after single loading of disposable drug cartridge, and configuration method therefor

Abstract

A needle-free injector capable of multiple injections after a single loading of a disposable drug cartridge, and a configuration method therefor. Said needle-free injector comprises: a housing (100), which is provided with a mounting cavity (101); an impact assembly (200), which is provided in the mounting cavity (101) of the housing (100), the impact assembly (200) having an impact portion (201); and a disposable drug cartridge assembly (300), which is mounted inside the housing (100), the disposable drug cartridge assembly (300) having a push rod (302). Before each injection, a first preset distance is present between the impact portion (201) of the impact assembly (200) and the push rod (302) of the disposable drug cartridge assembly (300), and the momentum of the impact assembly (200) during each injection is within the range of 0.21kg·m / s-2kg·m / s. Controlling the impact assembly (200) to impact the push rod (302) of the disposable drug cartridge assembly (300) during each injection, and controlling the momentum parameter of the impact make injection depths of multiple injections uniform and achieve micro-dose injection.

Description

Needle-free syringe with disposable core, single-time loading and multiple injections and configuration method thereof Technical Field

[0001] The present invention relates to the field of medical devices, and in particular to a needle-free syringe with a disposable core, single-time medicine loading and multiple injections, and a configuration method thereof. Background Art

[0002] A needle-free syringe is a syringe that does not require a needle. It usually uses high pressure to spray the injection liquid into human tissue to achieve drug administration. It is a safer, more hygienic and comfortable injection method.

[0003] The treatment of certain diseases requires multiple injections, such as vitiligo treatment, scar treatment, and certain surgical anesthesia. It is necessary to load the medicine once and inject multiple times to facilitate the operation of medical staff.

[0004] Some needle-free syringes can achieve multiple injections with one loading. The cavity tube structure of one needle-free syringe is complex and needs to be disassembled, cleaned, sterilized and disinfected after each use, and reassembled before the next use, which is troublesome to operate. Another needle-free syringe uses a disposable drug core. This solution is convenient for injection, but there are problems such as the depth of the injection getting deeper from the first injection to the last injection (that is, the depth of the first injection is shallow, the depth of the subsequent injection is deep, and the depth of multiple injections is uneven) and small doses cannot be injected.

[0005] Therefore, there is a need for further improvement of the existing single-load multiple-injection needle-free syringe.

[0006] The information disclosed in this background section is only intended to enhance understanding of the overall background of the invention and should not be considered as an admission or any form of suggestion that the information constitutes the prior art already known to a person skilled in the art.

[0007] Summary of the Invention

[0008] The purpose of the present invention is to provide a needle-free syringe with a disposable core and single-charge multiple injections and a configuration method thereof. The needle-free syringe with a disposable core and single-charge multiple injections can improve the depth unevenness of multiple injections and can achieve micro-dose injections.

[0009] According to a first aspect of the present invention, there is provided a method for configuring a needle-free syringe for single-charge, multiple-injection use of a disposable core, comprising: a) providing a shell having a mounting cavity; b) arranging an impact assembly within the mounting cavity of the shell; c) mounting the disposable core assembly for single-charge, multiple-injection use to the shell; and d) ensuring that a first predetermined distance exists between an impact portion of the impact assembly and a push rod of the disposable core assembly before each injection, and that a momentum of the impact assembly is within a range of 0.21 kg·m / s to 2 kg·m / s when each injection is implemented.

[0010] Preferably, the first predetermined distance is greater than or equal to 1 mm.

[0011] Preferably, the momentum of the impact assembly during each injection is in the range of 0.21 kg·m / s to 1 kg·m / s.

[0012] Preferably, the momentum of the impact assembly during each injection is in the range of 0.3 kg·m / s to 0.7 kg·m / s.

[0013] Preferably, a reset member is provided in the mounting cavity of the housing, the reset member is mounted to the mounting cavity and can provide an elastic reset force to the impact assembly, so that the impact assembly is reset after each injection.

[0014] Preferably, the disposable core single-charge multiple-injection needle-free syringe further comprises: a lumen threadedly connected to the front end of the mounting cavity, the front end of the impact portion extending into the lumen, and the rear end of the push rod extending into the lumen.

[0015] Preferably, the disposable core assembly further comprises a core barrel, and the core barrel of the disposable core assembly is detachably connected to the front end of the lumen.

[0016] Preferably, the needle-free syringe with a disposable core and single-charge and multiple-injection function further includes: a spring positioning bead, which is mounted to the inner side wall of the front end of the shell; wherein the outer side wall of the front end of the cavity has a positioning groove, and the ball end of the spring positioning bead can be elastically inserted into the positioning groove.

[0017] Preferably, the front end of the shell has a mounting barrel; the needle-free syringe further includes: a screw sleeve, the front of which wraps the cavity, and the rear of the screw sleeve wraps the front of the mounting barrel; and a gasket, which is arranged between the front of the screw sleeve and the cavity.

[0018] According to a second aspect of the present invention, a needle-free syringe with a disposable core for single-time loading and multiple injections is provided, comprising: a shell having a mounting cavity; an impact assembly disposed in the mounting cavity of the shell, the impact assembly having an impact portion; and a disposable core assembly mounted to the shell, the disposable core assembly having a push rod; wherein, before each injection, there is a first predetermined distance between the impact portion of the impact assembly and the push rod of the disposable core assembly, and when each injection is implemented, the momentum of the impact assembly is in the range of 0.21 kg·m / s to 2 kg·m / s.

[0019] Preferably, the first predetermined distance is greater than or equal to 1 mm.

[0020] Preferably, the momentum of the impact assembly during each injection is in the range of 0.21 kg·m / s to 1 kg·m / s.

[0021] Preferably, the momentum of the impact assembly during each injection is in the range of 0.3 kg·m / s to 0.7 kg·m / s.

[0022] Preferably, the disposable core, single-charge, multiple-injection needle-free syringe further comprises: a reset member, which is installed in the installation cavity and can provide an elastic reset force to the impact assembly.

[0023] Preferably, the disposable core single-charge multiple-injection needle-free syringe further comprises: a lumen threadedly connected to the front end of the mounting cavity, the front end of the impact portion extending into the lumen, and the rear end of the push rod extending into the lumen.

[0024] Preferably, the disposable core assembly further comprises a core barrel, and the core barrel of the disposable core assembly is detachably connected to the front end of the lumen.

[0025] Preferably, the disposable core single-charge multiple-injection needle-free syringe further includes: a spring positioning bead mounted to the inner side wall of the front end of the shell; wherein the outer side wall of the front end of the cavity has a positioning groove, and the ball end of the spring positioning bead can be elastically inserted into the positioning groove.

[0026] Preferably, a plurality of positioning grooves are provided and are evenly distributed along the circumferential surface.

[0027] Preferably, the front end of the shell has a mounting barrel; the disposable core single-charge multiple-injection needle-free syringe further includes: a screw sleeve, the front of which wraps the cavity, and the rear of the screw sleeve wraps the front of the mounting barrel; and a gasket, which is arranged between the front of the screw sleeve and the cavity.

[0028] Preferably, the screw sleeve includes a screw sleeve body and a baffle extending radially inward from the front end of the screw sleeve body.

[0029] Preferably, the impact assembly further includes: a piston, which can be slidably installed in the installation cavity, and the rear end of the impact part is fixed to the piston; a positioning sleeve, the rear end of which is fixed to the piston, the positioning sleeve has a penetrating accommodating cavity in the front and rear directions, and the reset member is sleeved on the positioning sleeve, and before each injection, there is a second predetermined distance between the positioning sleeve and the front inner wall of the shell, wherein the second predetermined distance is greater than the first predetermined distance.

[0030] The embodiment of the present invention can make the depth of multiple injections uniform and achieve micro-dose injection each time by controlling the impact component to impact the push rod of the disposable core component during each injection and controlling the momentum parameters of the impact.

[0031] The methods and apparatus of the present invention have other features and advantages that will be apparent from, or will be described in detail in, the accompanying drawings and subsequent embodiments incorporated herein, which together serve to explain the specific principles of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] FIG1 is a first cross-sectional view of a needle-free syringe according to an embodiment of the present invention;

[0033] FIG2 is an enlarged schematic diagram of point A in FIG1 ;

[0034] FIG3 is a schematic structural diagram of a lumen;

[0035] Figure 4 is a schematic structural diagram of the screw sleeve;

[0036] FIG5 is a schematic cross-sectional view of the screw sleeve;

[0037] Figure 6 is a schematic structural diagram of a gasket;

[0038] FIG7 is a schematic cross-sectional view of a gasket;

[0039] FIG8 is a schematic diagram of the matching of the screw sleeve, the gasket and the cavity tube;

[0040] FIG9 is a first cross-sectional view of a needle-free syringe according to an embodiment of the present invention;

[0041] FIG10 is an enlarged schematic diagram of point A in FIG9 ;

[0042] FIG11 is a schematic cross-sectional view of the impact assembly;

[0043] FIG12 is a schematic structural diagram of a disposable drug core assembly.

[0044] Explanation of the figure marks: 100: Shell 101: Mounting cavity 102: Mounting cylinder 103: Front inner wall 200: Impact assembly 201: Impact part 202: Piston 203: Positioning sleeve 203A: Accommodating cavity 203B: Front end face 206: Front end face 300: Disposable core assembly 301: Core cylinder 302: Push rod 303: Rear end face 400: Resetting member 500: Lumen 501: Positioning groove 601: Spring positioning bead 602: Sleeve 603: Gasket 606: Sleeve body 607: Baffle 608: Gasket rear part 609: Gasket front part 610: Incision 700: Handle part 701: Trigger 702: Gas channel 703: Inlet.

[0045] It should be understood that the accompanying drawings are not necessarily drawn to scale, but rather present simplified representations of various features to illustrate the basic principles of the invention. The specific design features disclosed in the present invention (including, for example, specific dimensions, directions, locations, and shapes) will be determined in part by the specific intended application and use environment.

[0046] In the figures, like reference numbers refer to the same or equivalent parts of the present invention throughout the several figures of the drawing. DETAILED DESCRIPTION

[0047] Reference will now be made in detail to various embodiments of the present invention, examples of which are presented in the accompanying drawings and described below. Although the present invention will be described in conjunction with the exemplary embodiments, it should be understood that this description is not intended to limit the invention to these exemplary embodiments. On the contrary, the present invention is intended to cover not only these exemplary embodiments, but also various alternative forms, modifications, equivalent forms and other embodiments that may be included within the spirit of the invention and the scope defined by the appended claims.

[0048] When an element is referred to as being “on” or “over” another element, the element may be in contact with the other element, or intervening elements may also be present.

[0049] The embodiment of the present invention is introduced by taking a gun-type needle-free injector as an example. The type of needle-free injector is not limited to the gun-type, and may also be a pen-type or other types.

[0050] The power source of the embodiment of the present invention is selected from gas source. In addition to gas source, the power source here can also be spring driven, electric or other forms.

[0051] 1 to 12 , a needle-free syringe with a disposable core and single-time loading and multiple injections according to an embodiment of the present invention will be described.

[0052] Figure 1 is a first cross-sectional view of a needle-free syringe according to an embodiment of the present invention; Figure 2 is an enlarged schematic view of point A in Figure 1; Figure 3 is a structural schematic view of a lumen; Figure 4 is a structural schematic view of a screw sleeve; Figure 5 is a cross-sectional schematic view of a screw sleeve; Figure 6 is a structural schematic view of a gasket; Figure 7 is a cross-sectional schematic view of a gasket; Figure 8 is a schematic view of the coordination of a screw sleeve, a gasket and a lumen; Figure 9 is a first cross-sectional view of a needle-free syringe according to an embodiment of the present invention; Figure 10 is an enlarged schematic view of point A in Figure 9; Figure 11 is a cross-sectional schematic view of an impact assembly; and Figure 12 is a structural schematic view of a disposable medicine core assembly.

[0053] As shown in FIG. 1 and FIG. 2 , the disposable core single-charge multiple-injection needle-free syringe according to the embodiment of the present invention includes: a housing 100 , a striker assembly 200 and a disposable core assembly 300 .

[0054] The housing 100 has a mounting cavity 101 .

[0055] The impact assembly 200 is disposed in the installation cavity 101 of the housing 100 , and the impact assembly 200 has a impact portion 201 .

[0056] The disposable core assembly 300 is mounted to the housing 100 , and the disposable core assembly 300 has a push rod 302 .

[0057] Before each injection, there is a first predetermined distance L1 between the impact part 201 of the impact assembly 200 and the push rod 302 of the disposable core assembly 300, and the momentum of the impact assembly 200 during each injection is in the range of 0.21kg·m / s to 2kg·m / s.

[0058] The embodiment of the present invention can make the depth of multiple injections uniform and achieve micro-dose injection by controlling the impact assembly 200 to impact the push rod 302 of the disposable core assembly 300 during each injection and controlling the momentum parameters of the impact.

[0059] After a large number of tests, it was found that giving the drug core push rod a certain impact momentum in each single injection can significantly improve the uneven depth of multiple injections with one charge, and injection of small doses can also be achieved.

[0060] In an exemplary embodiment, the momentum of the impact assembly 200 when each injection is performed is in the range of 0.21 kg·m / s to 1 kg·m / s.

[0061] In an exemplary embodiment, the momentum of the impact assembly 200 when each injection is performed is in the range of 0.3 kg·m / s to 0.7 kg·m / s.

[0062] The striking portion 201 is a striking rod.

[0063] In an exemplary embodiment, as shown in Figure 2, the first predetermined distance L1 is greater than or equal to 1 mm. For a configured disposable core single-charge multiple-injection needle-free syringe, the first predetermined distance L1 is constant.

[0064] In an exemplary embodiment, the first predetermined distance L1 is in the range of 2 mm to 8 mm.

[0065] In a further embodiment, the first predetermined distance L1 is in the range of 4 mm to 6 mm.

[0066] The range of the first predetermined distance L1 may be appropriately set according to the mass of the impact assembly 200 and the obtained driving force.

[0067] The first predetermined distance L1 generally does not exceed 30 mm.

[0068] In an exemplary embodiment, as shown in FIG1 , the disposable core single-charge multiple-injection needle-free syringe further includes: a reset member 400, which is installed in the installation cavity 101 and can provide an elastic reset force to the impact assembly 200. After each injection is completed, the elastic reset force can cause the impact assembly 200 to move backward to the initial position (i.e., reset).

[0069] In an exemplary embodiment, the reset member 400 may be a coil spring, and the type of the reset member 400 is not limited thereto. The reset member 400 may be any type in the prior art as long as it can achieve the above functions.

[0070] In an exemplary embodiment, as shown in FIG1 , the disposable core single-load, multiple-injection needle-free syringe further includes a lumen 500, which is threadedly connected to the front end of the mounting cavity 101. The front end of the impact portion 201 of the impact assembly 200 extends into the lumen 500, and the rear end of the push rod 302 extends into the lumen 500. By twisting the lumen 500, the position of the lumen 500 relative to the impact portion 201 can be changed for each single injection.

[0071] In an exemplary embodiment, as shown in FIG. 1 , the front end of the housing 100 has a mounting barrel 102 .

[0072] Specifically, the rear end of the lumen 500 has an external thread, the front end of the mounting cavity 101 (the front end of the mounting cylinder 102) has an internal thread, and the rear end of the lumen 500 is threadedly connected to the inner surface of the front end of the mounting cavity 101 (the front end of the mounting cylinder 102).

[0073] In an exemplary embodiment, as shown in FIG1 , the disposable core single-charge multiple-injection needle-free syringe further includes a spring-positioned ball 601 mounted to the inner side wall of the front end of the housing 100 .

[0074] As shown in FIG3 , the outer side wall of the front end of the cavity tube 500 has a positioning groove 501 , and the ball end of the spring positioning ball 601 can be elastically inserted into the positioning groove 501 .

[0075] In the embodiments of FIG. 1 and FIG. 3 , two positioning grooves 501 are provided, and the two positioning grooves 501 are symmetrically distributed on the circumferential surface of the lumen 500 .

[0076] The number of positioning grooves 501 can be adjusted according to circumstances, for example, it can be set to any number between 1 and 6. When the number of positioning grooves 501 is 2 or more than 2, they can be evenly distributed along the circumferential surface.

[0077] In an exemplary embodiment, a mounting hole is preset on the inner side wall of the front end of the housing 100 (the front end of the mounting cylinder 102 ), and the spring positioning ball 601 is installed in the mounting hole.

[0078] In an exemplary embodiment, as shown in Figures 1 and 12, the disposable core assembly 300 further has a core barrel 301, and the core barrel 301 of the disposable core assembly 300 can be detachably connected to the front end of the cavity tube 500, thereby detachably connecting the disposable core assembly 300 to the mounting barrel 102 at the front end of the shell 100.

[0079] In one embodiment, the front end of the lumen 500 has internal threads, and the rear end of the core cartridge 301 of the disposable core assembly 300 has external threads, so that the core cartridge 301 can be detachably connected to the front end of the lumen 500 .

[0080] In another embodiment, the core tube 301 and the lumen 500 may also be connected by snaps, so that the core tube 301 can be detachably connected to the front end of the lumen 500 .

[0081] In addition to the threaded connection and the snap connection, other forms of connection may be used to enable the core cartridge 301 to be detachably connected to the front end of the lumen 500 .

[0082] In an exemplary embodiment, as shown in FIG. 1 and FIG. 2 , the disposable core single-charge multiple-injection needle-free syringe further includes: a screw sleeve 602 and a gasket 603 .

[0083] The front portion of the screw sleeve 602 wraps the lumen 500 , and the rear portion of the screw sleeve 602 wraps the front portion of the mounting tube 102 .

[0084] The gasket 603 is disposed between the front portion of the screw sleeve 602 and the lumen 500 .

[0085] The screw sleeve 602 and the gasket 603 can prevent the lumen 500 from being screwed out of the mounting tube 102 by the user's mistaken operation. In addition, the gasket 603 can also prevent the lumen 500 from shaking due to the thread gap.

[0086] Specifically, as shown in FIG4 and FIG5, the screw sleeve 602 includes a screw sleeve body 606 and a baffle 607 extending radially inward from the front end of the screw sleeve body 606. The baffle 607 can block the gasket 603 to prevent the gasket 603 from falling off.

[0087] In an exemplary embodiment, as shown in Figures 6 and 7, the gasket 603 includes a gasket rear portion 608 and a gasket front portion 609, wherein the inner diameters of the gasket rear portion 608 and the gasket front portion 609 are the same, and the outer diameter of the gasket rear portion 608 is larger than the outer diameter of the gasket front portion 609, so that the screw sleeve 602 can clamp the gasket rear portion 608 to prevent the gasket 603 from sliding forward and falling off.

[0088] As shown in FIG. 6 , the spacer 603 has a cutout 610 to facilitate installation of the spacer 603 .

[0089] The material of the gasket 603 can be a material that is easily elastically deformed, such as plastic.

[0090] As shown in FIG. 8 , the screw sleeve body 606 wraps the gasket rear portion 608 , and the gasket front portion 609 is disposed between the baffle 607 and the cavity tube 500 .

[0091] In an exemplary embodiment, as shown in FIG. 1 and FIG. 11 , the impact assembly 200 further includes a piston 202 and a positioning sleeve 203 .

[0092] The piston 202 is slidably mounted in the mounting cavity 101 . The rear end of the impact portion 201 is fixed to the piston 202 , and the rear end of the reset member 400 is abutted against the front end of the piston 202 .

[0093] The rear end of the positioning sleeve 203 is fixed to the piston 202. The positioning sleeve 203 has an accommodating cavity 203A extending therethrough in the front-to-back direction. The reset member 400 is sleeved on the positioning sleeve 203. The front end 203B of the positioning sleeve 203 contacts the front inner wall 103 of the housing 100 and is blocked by the front inner wall 103, thereby achieving positioning.

[0094] The rear end of the impact portion 201 is fixed to the piston 202 .

[0095] The high-pressure gas provided by the gas source can contact and push the piston 202 to push the entire impact assembly 200 forward.

[0096] In an exemplary embodiment, as shown in FIG1 , the gun-type needle-free injector further includes a handle portion 700, which includes a trigger 701, a gas channel 702, and an inlet 703. High-pressure gas from an external gas source enters the gas channel 702 through the inlet 703, thereby applying a driving force to the piston 202. The needle-free injector can be activated by pulling the trigger 701.

[0097] The dimensions of the aforementioned components control the second predetermined distance L2 between the front end face 203B of the positioning sleeve 203 and the front inner wall 103 of the housing 100, as well as the first predetermined distance L1 between the front end face 206 of the impactor 201 and the rear end face 303 of the push rod 302 (where L2 > L1). The impact momentum of the impactor assembly 200 is generated by the power source causing the impactor assembly 200 to move within a distance L1. This momentum can be controlled by adjusting the power output of the power device, the first predetermined distance L1, and the mass of the impactor assembly 200. During each injection, the impactor assembly 200 moves the second predetermined distance L2. The positioning sleeve 203 stops when the front end face 203B contacts the front inner wall 103 of the housing 100. The impactor 201 moves the push rod 302 a distance (L2 - L1). The dose delivered by the entire mechanism is the product of (L2 - L1) and the cross-sectional area of ​​the inner cavity of the core barrel 301. At this point, the push rod 302 moves forward a distance (L2 - L1).

[0098] If the next injection is required, the lumen 500 needs to be manually rotated, and the spring positioning bead 601 slides out of the positioning groove 501. The lumen 500 drives the medicine core tube 301 and the push rod 302 to move into the cavity (i.e., move backward). When the spring positioning bead 601 falls into the next positioning groove 501, it stops rotating. The moving distance depends on the pitch of the rear end thread of the lumen 500 and the number of positioning grooves 501 set on the lumen 500. In the implementation schemes of Figures 1 and 3, the lumen 500 is provided with two upper and lower symmetrical positioning grooves 501. The lumen 500 can be positioned by the spring positioning bead 601, and the minimum adjustment distance is half of the rear end thread pitch of the lumen 500.

[0099] If there are N positioning grooves 501 , the minimum adjustment distance is one Nth of the rear end thread pitch of the lumen 500 .

[0100] If there is only one positioning groove 501, the lumen 500 is rotated one full circle each time.

[0101] The embodiment of the present invention further provides a method for configuring a needle-free syringe with a disposable core and a single charge for multiple injections, which can configure a needle-free syringe with a disposable core and a single charge for multiple injections as shown in Figures 1 to 12. The configuration method comprises:

[0102] a) A housing 100 is provided, wherein the housing has a mounting cavity 101 .

[0103] b) The impact assembly 200 is arranged in the installation cavity 101 of the housing 100 .

[0104] c) Installing the single-charge, multiple-injection disposable core assembly 300 into the housing 100 .

[0105] d) ensuring that a first predetermined distance exists between the impact portion 201 of the impact assembly 200 and the push rod 302 of the disposable core assembly 300 before each injection, and that the momentum of the impact assembly 200 during each injection is within a range of 0.21 kg·m / s to 2 kg·m / s.

[0106] The operation of the needle-free injector according to the embodiment of the present invention will be described below with reference to the accompanying drawings.

[0107] Prepare a disposable core assembly 300 filled with a full dose of liquid medicine and install it on the front end of the lumen 500. At this point, under the elastic restoring force provided by the restoring member 400, the impact assembly 200 is located at the rearmost end (i.e., the initial position), the front end face 203B of the positioning sleeve 203 and the front inner wall 103 of the housing 100 are spaced at a second predetermined distance L2, and the front end face 206 of the impact portion 201 and the rear end face 303 of the push rod 302 are spaced at a distance L1 (see Figures 1 and 2 for details).

[0108] Pulling the trigger 701 (i.e., starting the needle-free injector) causes the impact assembly 200 to move forward and gain impact momentum while overcoming the elastic restoring force of the reset member 400, so that the impact assembly 200 moves forward, and the momentum of the impact assembly 200 is in the range of 0.21 kg·m / s to 2 kg·m / s.

[0109] When the impact portion 201 moves forward (L2-L1), the front end surface 206 of the impact portion 201 impacts the rear end surface 303 of the push rod 302, thereby pushing the push rod 302 forward, causing the liquid medicine in the disposable core assembly 300 to begin to spray out until the front end surface 203B of the positioning sleeve 203 contacts the front inner wall 103 of the housing 100, at which point an injection is completed. At this time, the push rod 302 moves forward a distance of (L2-L1) (see Figures 9 and 10 for details). After the front end surface 203B of the positioning sleeve 203 contacts the front inner wall 103 of the housing 100, it is blocked by the front inner wall 103, thereby achieving positioning.

[0110] After a single injection is completed, the trigger 701 is released to disconnect the power source. Under the action of the elastic reset force provided by the reset member 400, the impact part 201 can move backward to the initial position, that is, the impact assembly 200 is reset.

[0111] At this point, since the push rod 302 has moved forward a distance, the lumen 500 is rotated so that the lumen 500 rotates clockwise 180° along the rear end thread, and the position of the disposable core assembly 300 is adjusted, so that the next injection can be performed. The above steps can achieve accurate adjustment of the injection dose and ensure that the momentum of each single injection is basically consistent. For the embodiments of Figures 1 and 3, the number of positioning grooves 501 is 2, and the lumen 500 can be rotated clockwise along the rear end thread by an integer multiple of 180°, that is, it can be rotated 180°, 360°, 540°, 720°, etc.

[0112] If there are N positioning grooves 501 , they can be rotated by an integer multiple of (360° / N).

[0113] In the initial stage of this rotation process, the spring positioning ball 601 is further compressed so that the ball end of the spring positioning ball 601 slides from the bottom of the originally matched positioning groove 501 along the side of the positioning groove 501 to the outer peripheral surface of the cavity 500.

[0114] In the middle stage of this rotation process, the ball end of the spring positioning ball 601 slides along the outer peripheral surface of the cavity 500 to another positioning groove 501, and the spring positioning ball 601 maintains the same compression degree (ie, the maximum compression degree).

[0115] At the end of this rotation process, the ball end of the spring positioning ball 601 slides from the outer circumference of the lumen 500 along the side of the other positioning groove 501 to the bottom of the other positioning groove 501. During this stage, the spring positioning ball 601 gradually returns to its initial compression level. When the ball end of the spring positioning ball 601 slides to the bottom of the other positioning groove 501, the lumen 500 is locked again by the spring positioning ball 601.

[0116] The injection depth is related to the puncture ability of the jet. The following methods are used to evaluate the injection depth:

[0117] (1) Skin B-ultrasound: For small-dose injections, the skin B-ultrasound image is not very clear, so it is rarely used. (2) Observe and compare the injection effects on volunteers. Poor puncture ability leads to more leakage and skin bumps. Strong puncture ability leads to less leakage, no skin bumps, or small skin bumps, and even slight bleeding. (3) Puncture of multi-layer plastic films of the same specifications. The stronger the puncture ability, the more layers of plastic film will be penetrated. For small-dose injections, the latter two methods are mainly used to determine the injection depth, and the two methods are used in combination.

[0118] The applicant conducted multiple experiments on the above-mentioned needle-free syringe with a disposable core and single-time loading and multiple injections. The experimental data are shown in the following table:

[0119] Table 1

[0120] Experimental data description:

[0121] 1. Momentum: The momentum in the test data is controlled by varying the mass of the impact component and the impact spacing. The test utilizes specialized equipment that allows for easy adjustment of the impact spacing and component mass.

[0122] 2. Stagnation pressure: This refers to the pressure generated within the drug solution during injection with a needle-free syringe. It is also referred to as "drug solution pressure," "stagnation pressure," and "stop pressure." The above experimental data were all tested using the same stagnation pressure of 20 MPa.

[0123] 3. Injection Liquid Fill Ratio: This represents the ratio of the volume of liquid injected into the disposable core assembly to the maximum volume it can accommodate. Failure to use appropriate momentum can significantly impact injection penetration depth, as different liquid volumes lead to varying compression and core expansion, resulting in varying penetration depths.

[0124] 4. Injection completion rate: It indicates the ratio of the volume of liquid injected into the recipient to the injection volume in a single injection. The larger the value, the more volume is injected into the recipient.

[0125] 5. Number of plastic film puncture layers: The number of plastic film layers that can be punctured using a certain parameter combination. The more puncture layers, the stronger the injection puncture ability and the deeper the puncture.

[0126] 6. RSD of the number of puncture layers at the same momentum: The relative standard deviation of the number of plastic film puncture layers 5 times at the same momentum. The larger the value, the worse the repeatability, the greater the deviation of the puncture layer number, and the more unstable it is.

[0127] 7. The injection completion rate and number of plastic film puncture layers in the table are the average values ​​of multiple tests.

[0128] From the above table, we can conclude that the relationship between the momentum P and the injection effect is:

[0129] 1. When 0kg·m / s<P<0.21kg·m / s, injection cannot be completed even with a higher stagnation pressure.

[0130] 2. When 0.21kg·m / s≤P<0.3kg·m / s, the injection completion rate is relatively low, resulting in waste of injection solution.

[0131] 3. When 0.3kg·m / s≤P≤0.7kg·m / s, the injection completion rate is above 90%, the number of plastic film puncture layers does not exceed 10 layers, and the RSD value of the number of plastic film puncture layers is less than 10%, indicating good stability.

[0132] 4. When 0.7kg·m / s<P≤1.0kg·m / s, the injection completion rate and the RSD value of the number of plastic film puncture layers are both good, but the number of plastic film puncture layers exceeds 10 layers, and the maximum is 15 layers. While achieving the injection effect, the injection depth is large, which causes greater injection damage. Therefore, it is not as good as the injection effect with a momentum of 0.3 (inclusive) to 0.7 (inclusive) kg·m / s.

[0133] 5. When 1.0 kg·m / s < P ≤ 2.0 kg·m / s, the injection completion rate is relatively low, and the RSD value of the number of plastic film puncture layers exceeds 20%, indicating poor injection stability. Because the momentum exceeds the injection system's stable value, leakage may occur in the internal sealing structure of the disposable injection core assembly. Although injection can be completed, its stability is reduced, resulting in poor injection depth stability compared to the range of 0.3 ≤ P ≤ 0.7 kg·m / s.

[0134] 6. When P>2.0kg·m / s, the disposable injection core assembly cannot withstand the momentum, causing the push rod to bend and deform during injection, making it impossible to spray the liquid.

[0135] The present invention only provides an example of a gun-type needle-free injector. By providing a certain impact momentum to the push rod 302 during each single injection, the uneven depth of multiple injections with a single charge can be improved, and even small doses can be injected. This principle can also be applied to spring-powered injectors, pen-type pneumatic injectors, and electric drives.

[0136] For convenience of explanation and precise definition of the appended claims, the terms "upper", "lower", "inner", "outer", "above", "below", "upper", "lower", "upward", "downward", "front", "back", "behind", "inside", "outside", "inward", "outward", "inner", "exterior", "inner", "external", "forward", and "backward" are used to describe the features of the exemplary embodiments with reference to the positions of such features as shown in the accompanying drawings.

[0137] The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. The foregoing descriptions are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and it is apparent that many variations and modifications are possible in light of the foregoing teachings. The exemplary embodiments have been selected and described to illustrate the specific principles of the invention and their practical application, thereby enabling others skilled in the art to make and utilize the various exemplary embodiments of the invention and their various alternatives and modifications. The scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for configuring a needle-free syringe with a disposable core for single-charge and multiple injections, characterized in that: include: a) providing a housing having a mounting cavity; b) disposing an impact assembly in the mounting cavity of the housing; c) installing a single-charge, multiple-injection disposable core assembly into the housing; d) ensuring that a first predetermined distance exists between the impact portion of the impact assembly and the push rod of the disposable core assembly before each injection, and the momentum of the impact assembly during each injection is within a range of 0.21 kg·m / s to 2 kg·m / s.

2. The method for configuring a needle-free syringe with a disposable core for single-charge and multiple injections according to claim 1, characterized in that: The first predetermined distance is greater than or equal to 1 mm.

3. The method for configuring a needle-free syringe with a disposable core for single-charge and multiple injections according to claim 1, characterized in that: The momentum of the impact assembly during each injection is in the range of 0.21 kg·m / s to 1 kg·m / s.

4. The method for configuring a needle-free syringe with a disposable core for single-charge and multiple injections according to claim 1, characterized in that: The momentum of the impact assembly during each injection is in the range of 0.3 kg·m / s to 0.7 kg·m / s.

5. The method for configuring a needle-free syringe with a disposable core for single-charge and multiple injections according to claim 1, characterized in that: A reset component is provided in the mounting cavity of the housing, the reset component is mounted to the mounting cavity and can provide an elastic reset force to the impact assembly so that the impact assembly is reset after each injection.

6. The method for configuring a needle-free syringe with a disposable core for single-charge and multiple injections according to claim 1, characterized in that: The disposable core single-charge multiple-injection needle-free syringe further comprises: The cavity tube is threadedly connected to the front end of the installation cavity, and the front end of the impact part extends to the The rear end of the push rod extends into the lumen.

7. The method for configuring a needle-free syringe with a disposable core for single-charge and multiple injections according to claim 6, characterized in that: The disposable core assembly further comprises a core barrel, and the core barrel of the disposable core assembly can be detachably connected to the front end of the lumen.

8. The method for configuring a needle-free syringe with a disposable core for single-charge and multiple injections according to claim 6, characterized in that: The disposable core single-charge multiple-injection needle-free syringe further comprises: a spring-positioned bumper, mounted to the inner side wall of the front end of the housing; Wherein, the outer side wall of the front end of the cavity tube has a positioning groove, and the ball end of the spring positioning ball can be elastically inserted into the positioning groove.

9. The method for configuring a needle-free syringe with a disposable core for single-time loading and multiple injections according to claim 6, characterized in that: The front end of the housing is provided with a mounting cylinder; The needle-free injector further comprises: a screw sleeve, the front portion of which wraps around the lumen, and the rear portion of which wraps around the front portion of the mounting tube; and A gasket is arranged between the front portion of the screw sleeve and the cavity tube.

10. A needle-free syringe with a disposable core for single loading and multiple injections, characterized in that: include: a housing having a mounting cavity; an impact assembly, which is disposed in the mounting cavity of the housing, and has an impact portion; as well as a disposable core assembly mounted to the housing, the disposable core assembly having a push rod; There is a first predetermined distance between the impact portion of the impact assembly and the push rod of the disposable core assembly before each injection, and the momentum of the impact assembly is within the range of 0.21 kg·m / s to 2 kg·m / s during each injection.

11. The needle-free syringe with a disposable core and single-charge and multiple-injection function according to claim 10, characterized in that: The first predetermined distance is greater than or equal to 1 mm.

12. The needle-free syringe with a disposable core and single-charge and multiple-injection function according to claim 10, characterized in that: The momentum of the impact assembly during each injection is in the range of 0.21 kg·m / s to 1 kg·m / s.

13. The needle-free syringe with a disposable core and single-charge and multiple-injection function according to claim 10, characterized in that: The momentum of the impact assembly during each injection is in the range of 0.3 kg·m / s to 0.7 kg·m / s.

14. The needle-free syringe with a disposable core and single-charge and multiple-injection function according to claim 10, characterized in that: It further includes: A reset member is installed in the installation cavity and can provide an elastic reset force to the impact assembly.

15. The needle-free syringe with a disposable core and single-charge and multiple-injection function according to claim 10, characterized in that: It further includes: The cavity tube is threadedly connected to the front end of the mounting cavity, the front end of the impact part extends into the cavity tube, and the rear end of the push rod extends into the cavity tube.

16. The needle-free syringe with a disposable core and single-charge and multiple-injection function according to claim 15, characterized in that: The disposable core assembly further comprises a core barrel, and the core barrel of the disposable core assembly can be detachably connected to the front end of the lumen.

17. The needle-free syringe with a disposable core and single-charge and multiple-injection function according to claim 15, characterized in that: It further includes: a spring-positioned bumper, mounted to the inner side wall of the front end of the housing; Wherein, the outer side wall of the front end of the cavity tube has a positioning groove, and the ball end of the spring positioning ball can be elastically inserted into the positioning groove.

18. The needle-free syringe with a disposable core and single-charge and multiple-injection function according to claim 17, characterized in that: There are multiple positioning grooves, which are evenly distributed along the circumferential surface.

19. The needle-free syringe with a disposable core and single-charge and multiple-injection function according to claim 15, characterized in that: The front end of the housing is provided with a mounting cylinder; The disposable core single-charge multiple-injection needle-free syringe further comprises: a screw sleeve, the front portion of which wraps around the lumen, and the rear portion of which wraps around the front portion of the mounting tube; and A gasket is arranged between the front portion of the screw sleeve and the cavity tube.

20. The needle-free syringe with a disposable core and single-charge and multiple-injection function according to claim 19, characterized in that: The screw sleeve comprises a screw sleeve body and a baffle extending radially inward from the front end of the screw sleeve body.

21. The needle-free syringe with a disposable core and single-charge and multiple-injection function according to claim 19, characterized in that: The impact assembly further comprises; a piston slidably mounted in the mounting cavity, wherein the rear end of the impact portion is fixedly connected to the piston; A positioning sleeve, the rear end of which is fixed to the piston, has a penetrating accommodating cavity in the front-to-back direction, and the reset member is sleeved on the positioning sleeve. Before each injection, there is a second predetermined distance between the positioning sleeve and the front inner wall of the shell, wherein the second predetermined distance is greater than the first predetermined distance.

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