A pre-filled catheter flusher

Abstract

The application discloses a pre-filled catheter flusher, and belongs to the technical field of medical devices. The flusher comprises a liquid storage container and an injection head. The liquid storage container comprises a liquid storage part and a pressure applying part. The liquid storage part comprises a liquid storage cavity for storing flushing liquid. The pressure applying part is used for extruding the liquid storage part. The liquid storage part is deformable. The injection head is connected with the liquid storage part and communicates with the liquid storage cavity. The pressure applying part can comprise a plurality of inflatable extruding members arranged around the liquid storage part, or be in the form of a strip, a table body or a spherical structure extending into a recessed space of the garlic-shaped liquid storage part. The application has the advantages of simple structure, separate design of the liquid storage part and the pressure applying part, reduced material cost and assembly difficulty, efficient and uniform liquid discharge realized by the deformable liquid storage cavity cooperating with the pressure applying part, direct communication structure of the injection head avoiding pollution, reduced cost under the premise of ensuring flushing effect, and satisfaction of the demand of large-scale clinical use.

Description

Technical Field

[0001] This invention relates to medical devices, and more specifically, to a pre-filled catheter flushing device. Background Technology

[0002] In clinical nursing practice, catheter maintenance is a crucial aspect of intravenous therapy, directly impacting patient treatment outcomes and safety. Whether it's a central venous catheter (CVC) or a peripherally inserted intravenous catheter (PIV), improper catheter maintenance can lead to three major clinical risks: infection, catheter occlusion, and phlebitis. Among these, flushing and sealing the catheter to maintain patency is a key aspect of catheter maintenance. According to clinical nursing guidelines, flushing and sealing should be performed frequently after intravenous catheterization, before and after each intravenous infusion, and before and after blood collection / transfusion / parenteral nutrition, resulting in a significant demand for disposable consumables.

[0003] Pre-filled catheter flushing devices, used clinically for flushing and sealing catheters, have become high-volume disposable medical consumables. Currently, most mainstream products on the market employ a syringe piston structure, consisting of a rigid pre-filled syringe with a barrel, plunger, piston, and connector.

[0004] However, the aforementioned traditional piston-type pre-charge flusher has the following prominent problems: First, the structure is complex and the manufacturing cost is high. Traditional rigid syringes require multiple precision-fitting parts such as the barrel, piston, and plunger. The piston and barrel must ensure sealing and smooth sliding, which requires high processing precision and materials. The manufacturing process is complex, resulting in a high cost per unit.

[0005] Secondly, the materials used are large and the assembly process is complicated. Traditional products, such as Becton Dickinson's BD PosiFlush series, mostly use rigid polypropylene injection molded parts for the cylinder, and the push rod and piston need to be molded separately before assembly. The overall material cost and labor assembly cost are high, which is not conducive to large-scale cost reduction.

[0006] Third, the push-rod pressure application method has limitations. Medical staff need to use both hands simultaneously: one hand to hold the syringe, and the other to push the plunger, making it less convenient to operate. While some designs incorporate a push handle (thumb pressing) for assistance, the overall structure remains unchanged.

[0007] Fourth, the anti-backflow mechanism increases complexity. To prevent blood backflow, existing products typically require additional structures such as valves or pistons at the end of the injection head, further increasing the number of components and assembly difficulty.

[0008] In addition, early catheter flushing devices, such as the pre-filled piston injectors designed by Mueller et al. (US4878903A, US4954239A), although they introduced the concept of "single-dose pre-filling" and simplified the clinical fluid collection process, were still essentially traditional piston injector structures, and the cost problem was not fundamentally solved.

[0009] In summary, existing pre-filled catheter flushing devices suffer from problems such as complex structure, numerous parts, high material costs, and cumbersome assembly processes. As disposable consumables consumed in large quantities daily by hospitals and clinics, their high unit cost places a significant financial burden on medical institutions. Therefore, there is an urgent need for a new type of pre-filled catheter flushing device that features a simplified structure, low cost, convenient operation, and excellent flushing effect to meet the needs of large-scale clinical use. Summary of the Invention

[0010] In view of the shortcomings of the existing technology, the purpose of this invention is to provide a pre-filled catheter flushing device with a simplified structure and low cost.

[0011] To achieve the above objectives, the present invention provides the following technical solution: A pre-filled catheter flushing device includes a reservoir and an injection head, characterized in that the reservoir includes a reservoir section and a pressure application section, the reservoir section includes a reservoir cavity for storing flushing fluid, the pressure application section is used to squeeze the reservoir section, the reservoir section is deformable, and the injection head is connected to the reservoir section and communicates with the reservoir cavity.

[0012] Furthermore, the liquid storage chamber has a rectangular, trapezoidal, triangular, or circular cross-section, and the pressure application part includes several extrusion components arranged around the liquid storage part. Each extrusion component includes an air-filled extrusion chamber and is deformable. The liquid storage part and the extrusion components can be made of polyvinyl chloride, TPE, polypropylene, or polyethylene.

[0013] Furthermore, several extrusion components are fixed to the liquid storage section, which can be done by means of welding, bonding, etc.

[0014] Furthermore, a connecting member connects two adjacent extrusion components, and the connecting member is fixed to the liquid storage section. The extrusion components and the connecting member can be integrally formed by folding a single sheet of film material (or two sheets of film) to create a space. The film material is then welded together using a welding device to form an extrusion area. After inflating the extrusion area, it is sealed to form the extrusion component. The connecting member is formed by the portion between two adjacent extrusion components. The extrusion component can also be made of an inflatable airbag, and the connecting member can be made of a film.

[0015] Furthermore, the liquid storage section is garlic-shaped and includes a recessed space. One end of the pressure-applying section extends into the recessed space and cooperates with the liquid storage section. The liquid storage section can be composed of a bag-shaped body—the bottom of the bag-shaped body is turned upward and inward to form a recessed space.

[0016] Furthermore, the pressure-applying part is strip-shaped, platform-shaped, or spherical, and can be solid or hollow, and can be made of materials such as polyvinyl chloride, TPE, polypropylene, polyethylene, rubber, or silicone.

[0017] Furthermore, the side wall of the pressure application section is provided with several protrusions that correspond to and cooperate with the liquid storage section. The protrusions may also be made of polyethylene foam, rubber or silicone.

[0018] Furthermore, one end of the extrusion member extends toward the injection head, and the other end of the extrusion member extends out of the liquid reservoir.

[0019] Furthermore, the injection head is tubular, and a flexible membrane is provided inside the injection head. The flexible membrane has dot-shaped, straight, cross-shaped, or star-shaped slits.

[0020] Furthermore, the injection head is equipped with a sealing cap that is detachably connected to it, and the injection head is also equipped with a push handle.

[0021] By adopting the above technical solution, the beneficial effects of the present invention are as follows: Simplified Structure and Reduced Costs: This invention effectively simplifies the internal structure of the irrigator, and the separate design of the liquid storage section and the pressure application section reduces material costs and assembly difficulty. The overall solution reduces the cost per unit while ensuring irrigation effectiveness, meeting the needs of large-scale clinical use.

[0022] Optimized production processes: The flexible pressure characteristics of inflatable extruded components eliminate the need for precision machining, reducing investment in production equipment; the wraparound arrangement design can be achieved through a simple heat-sealing process, reducing assembly time. Multiple material options provide flexibility for different cost control needs.

[0023] Improved operability and drainage: The garlic-shaped surface morphology optimizes grip stability, facilitating one-handed operation by medical staff. The membrane properties of the connecting components enable adjacent extrusion components to form a linkage mechanism, automatically adjusting the pressure distribution during pressurization. This avoids uneven deformation of the reservoir cavity caused by localized pressure concentration, ensuring the stability of the liquid extrusion process.

[0024] Enhanced adaptability and pressure application efficiency: The pressure application unit comes in various shapes to precisely match clinical pressure application needs and fluid reservoirs of different shapes. Through the synergistic effect of the raised strips and elastic materials, the pressure application unit improves the compression efficiency of the fluid reservoir, reducing irrigation fluid residue.

[0025] Ensuring a tight seal and easy operation: The flexible membrane structure within the injection head guarantees a tight seal when not in use. The push handle enhances the stability of catheter connection operations. The removable and reconnectable design of the sealing cap effectively prevents contamination. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of Embodiment 1.

[0027] Figure 2 This is a cross-sectional structural diagram of Example 1.

[0028] Figure 3 This is a schematic diagram of the structure of Example 2.

[0029] Figure 4 This is a cross-sectional structural diagram of Example 2.

[0030] Figure 5 This is a cross-sectional view of the injection tube.

[0031] Explanation of reference numerals in the attached drawings: 1-liquid reservoir, 11-liquid reservoir cavity, 12-recessed space; 2-pressure application part, 21-extrusion component, 211-extrusion cavity, 22-connecting component, 23-protrusion strip; 3-injection head, 31-flexible membrane, 311-gap, 32-check ring, 33-push handle; 4-sealing cap. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0034] The pre-filled catheter flushing device of the present invention includes a reservoir, an injection head 3, and a sealing cap 4. The reservoir consists of a reservoir 1 and a pressure application 2. The reservoir 1 includes a reservoir chamber 11 for storing flushing fluid. The pressure application 2 is used to squeeze the reservoir 1. The reservoir 1 is made of a deformable material. The injection head 3 is connected to the reservoir 1 and communicates with the reservoir chamber 11. The injection head 3 is provided with a push handle 33.

[0035] The system comprises the following components: The reservoir 1 is a deformable cavity for containing the flushing fluid, which can be achieved by heat-sealing a polyvinyl chloride (PVC) film into a sealed bag. Its deformability allows for volume changes under external pressure. The pressure application section 2 is a force-applying component independent of the reservoir 1, which can be made of TPE material injection-molded into a strip-shaped extrusion plate. It mechanically compresses the outer wall of the reservoir 1 to expel the fluid. The injection head 3 is the fluid output channel, which can be made of medical-grade polypropylene tubing heat-fused to the reservoir 1. Its unidirectional design prevents backflow. The sealing cap 4 is an independent component covering the port of the injection head 3, which can be made of polyethylene, polypropylene, or silicone. For example, silicone can be used to form an elastic sleeve structure, which fits tightly against the outer wall of the injection head 3 through elastic deformation, achieving physical isolation. The push handle 33 is an operating component located outside the injection head 3. It can be integrally molded with the injection head 3 using injection molding or assembled separately, and is used to provide a force fulcrum to assist in the connection operation between the flushing device and the catheter.

[0036] Specifically, the reservoir 1 maintains its original volume for storing flushing fluid when unpressurized. When the pressure-applying part 2 applies external force, the reservoir 1 deforms, compressing the space of the reservoir cavity 11 and forcing the liquid out through the injection head 3. The pressure-applying part 2 is independently located outside the reservoir 1 and applies linear compression through direct contact with the outer wall of the reservoir 1. This mechanical pressure application method eliminates the need for an internal spring or piston structure. The direct connection between the injection head 3 and the reservoir cavity 11 eliminates intermediate tubing, and the use of medical-grade materials for heat fusion connection ensures a tight seal, avoiding the assembly gaps 311 caused by traditional threaded connections.

[0037] Example 1:

[0038] The liquid storage chamber 11 has a rectangular, trapezoidal, triangular, or circular cross-section. The pressure application part 2 includes several extrusion members 21, which are arranged around the liquid storage part 1. Each extrusion member 21 includes an air-filled extrusion chamber 211. The extrusion members 21 are deformable. The liquid storage part 1 and the extrusion members 21 can be made of polyvinyl chloride, TPE, polypropylene, or polyethylene. The extrusion members 21 are fixed to the liquid storage part 1 by welding or bonding. A connecting member 22 connects two adjacent extrusion members 21 and is fixed to the liquid storage part 1. The extrusion members 21 and the connecting members 22 can be integrally formed by folding a thin film or creating a space between two films. The films are then welded together to form an extrusion area. After inflating the extrusion area, it is sealed to form the extrusion member 21. The portion between two adjacent extrusion members 21 forms the connecting member 22. The extrusion members 21 can also be made of an inflatable airbag, and the connecting member 22 can be made of a thin film.

[0039] The liquid storage chamber 11 has a rectangular, trapezoidal, triangular, or circular cross-section, representing a regular geometric shape. Specifically, it can be formed using thermoforming processes to shape the material into the corresponding cross-sectional shape, achieving uniform deformation of the liquid storage section 1 under pressure through geometric symmetry. The extrusion components 21 are arranged around the liquid storage section 1, consisting of multiple independent inflation units distributed circumferentially. Specifically, they can be formed by film welding into a ring-shaped array of inflation cavities, creating a uniform pressure surface through a surrounding layout. The air-filled extrusion chamber 211 is a closed cavity filled with a gaseous medium. Specifically, it can be formed by double-layer film welding, followed by air filling and sealing, utilizing the compressibility of gas to achieve flexible pressure application. The liquid storage section 1 and the extrusion components 21 are made of polyvinyl chloride, TPE, polypropylene, or polyethylene, using thermoplastic elastomers or general-purpose plastics as the main material. Specifically, they can be processed using blow molding, injection molding, or heat sealing processes, utilizing the elasticity and cost advantages of the materials to meet structural deformation requirements and economic requirements.

[0040] The connecting member 22 is a thin film structure disposed between adjacent extrusion members 21. Specifically, it can be achieved by welding the thin film material to form a continuous connecting area, used to maintain the relative position of the extrusion members 21 and transmit pressure. The integral molding means that the extrusion members 21 and the connecting member 22 are formed into an integral structure using the same material. Specifically, it can be achieved by folding a single layer of film and welding it to form an inflatable chamber, reducing assembly steps and the number of parts. The fusion welding to form the extrusion area involves locally fusing the thin film material to form a closed area through hot pressing. Specifically, it can be achieved by forming a predetermined shape of welding line on the film using high-frequency fusion welding equipment, used to delineate the boundary between the inflatable chamber and the non-inflatable area. The inflatable airbag is an elastic component filled with gas to form an expansion structure. Specifically, it can be achieved by sealing a polyvinyl chloride film and then injecting air, used to generate uniform pressure through airbag expansion.

[0041] Specifically, the regular cross-sectional shape of the liquid storage chamber 11 causes symmetrical deformation under pressure, preventing the liquid flow path from deviating. The surrounding inflatable extrusion members 21 deform under external pressure, distributing the extrusion force to the circumferential surface of the liquid storage chamber 11 through the uniform transmission of the gas medium. The inflatable cavity of the extrusion member 21 maintains its initial shape when unpressurized; when external pressure is applied, the cavity volume shrinks, and the increased internal air pressure creates a reaction force, pushing the liquid storage chamber 11 to contract radially. When the liquid storage section 1 and the extrusion member 21 are made of polyvinyl chloride or TPE, the material's elastic modulus allows the liquid storage chamber 11 to partially return to its original shape after pressure is released, resulting in a controllable liquid extrusion volume. When polypropylene or polyethylene is used, the material rigidity increases while the cost decreases, making it suitable for applications where liquid is emptied in a single extrusion. After pre-setting the installation position of the extrusion member 21 on the surface of the liquid storage section 1, the contact area is locally heated using a welding device, causing the surface materials of the liquid storage section 1 and the extrusion member 21 to melt and interpenetrate, forming an integrated connection structure after cooling. Alternatively, an automated dispensing device can be used to apply adhesive to the surface of the liquid storage section 1, and the extrusion member 21 can be pressed into the predetermined position for curing.

[0042] Specifically, the film material is folded and welded to form spaced inflatable areas. After inflation, the expansion forms extrusion members 21, while the uninflated portions naturally form film-shaped connecting members 22. After the connecting members 22 are fixed on the surface of the liquid storage section 1, adjacent extrusion members 21 deform synchronously through film connections. When the liquid storage section 1 is compressed, the connecting members 22 transmit pressure, causing multiple extrusion members 21 to work together to ensure a uniform distribution of storage pressure. During the manufacturing process, a single film is folded and welded to form a continuous inflation unit. After inflation and sealing, it directly forms an integral structure including extrusion members 21 and connecting members 22, eliminating the need for separate assembly of the airbag and connecting components.

[0043] Optionally, the extrusion member 21 is strip-shaped and air-bag-like, with several of them bonded or welded to the liquid storage section 1. One end of the extrusion member 21 extends toward the injection head 3, and the other end extends out of the liquid storage section 1. Specifically, the end of the extrusion member 21 extending toward the injection head 3 extends axially along the liquid storage section 1 toward the liquid outlet direction. This can be achieved by using an elastic thin film material to form a continuous strip structure through heat melting. Its function is to directly transmit the externally applied extrusion force to the end region of the liquid storage chamber 11. The other end of the extrusion member 21 extending out of the liquid storage section 1 extends beyond the outer wall of the liquid storage section 1, forming an exposed section. This can be formed by using a sheet structure of the same material as the liquid storage section 1, folded and sealed. Its function is to provide an operating fulcrum for external force application and avoid the need for additional independent force-applying components.

[0044] Specifically, when an external force is applied to the exposed section of the extrusion member 21 extending from the liquid reservoir 1, the deformation of the extrusion member 21 is transmitted axially to the end near the injection head 3, causing the end region of the liquid reservoir 11 to be preferentially deformed by pressure. Since the extension direction of the extrusion member 21 is consistent with the discharge direction of the liquid reservoir 11, the pressure transmission path is shortened, and the liquid in the liquid reservoir 11 flows along the direction of the injection head 3 under the action of the pressure gradient. The transition area formed between the exposed section of the extrusion member 21 and the outer wall of the liquid reservoir 1 can serve as a contact surface for finger pressing. For example, a corrugated surface or raised structure can be used to enhance friction, thereby achieving a stable grip without the need for an additional anti-slip layer.

[0045] Example 2:

[0046] The liquid storage section 1 is garlic-shaped and includes a recessed space 12. One end of the pressure-applying section 2 extends into the recessed space 12 and corresponds to and cooperates with the liquid storage section 1. The liquid storage section 1 is composed of a bag-shaped body. The bottom of the bag-shaped body is turned upward and inward to form the recessed space 12. The raised part is welded or bonded to other parts of the liquid storage section 1 at intervals to form a garlic-shaped structure. The liquid storage section 1 has several spaced liquid storage chambers 11, and each liquid storage chamber 11 is connected to the injection head 3. The pressure-applying section 2 is strip-shaped, platform-shaped, or spherical, and can be solid or hollow, and can be made of polyvinyl chloride, TPE, polypropylene, polyethylene, rubber, or silicone. The pressure-applying section 2 can be bonded and fixed to the liquid storage section 1, or it can be separately fitted to the liquid storage section 1. The side wall of the pressure-applying section 2 is provided with several protruding strips 23 that correspond to and cooperate with the liquid storage section 1. The protruding strips 23 are made of polyethylene foam, rubber, or silicone.

[0047] The garlic-shaped structure refers to the undulating shape of the outer surface of the liquid storage section 1. A recessed space 12 is formed by folding the bottom of the bag-like body, which increases gripping friction and facilitates pressure application. The interior of the liquid storage chamber 11 can be divided into multiple independent or semi-independent spaces. These spaces are separated by connecting areas formed by welding or bonding, which guide the flushing fluid to form a multi-channel flow path. The design of the pressure applying section 2 extending into the recessed space 12 allows it to directly act on the raised portion of the liquid storage chamber 11, thereby transmitting pressure more efficiently.

[0048] Specifically, the bag body can be processed into a hollow garlic-shaped bag using molding equipment, and the recessed space 12 is formed by hot pressing. The concave and convex surfaces of the garlic-shaped structure not only make it easy to hold, but also guide the direction of force during extrusion, making the flushing liquid discharge smoother. Similarly, the inwardly raised recessed space 12 can be fixed to the main body of the liquid storage section 1 by point or line connection, forming the recessed space 12 and the spaced liquid storage chambers. When the pressure section 2 applies pressure to the recessed space 12, the connecting area of ​​the raised part is pushed inward, and the flushing liquid in the liquid storage chamber is squeezed and flows along the multi-channel to the injection head 3. The spaced liquid storage chambers prevent liquid backflow and improve extrusion efficiency by separating the flow paths.

[0049] Among them, the strip-shaped pressure structure is a slender, elongated structure, which can be implemented using a straight or curved cross-section design. It is suitable for directional pressure applications, concentrating pressure through linear contact surfaces. The frustum-shaped pressure structure has a multi-faceted geometric shape, which can be implemented using a prism or truncated pyramid structure. It improves pressure stability through multi-directional contact surfaces. The spherical pressure structure has a curved shape, which can be implemented using a complete sphere or hemisphere shape. It achieves uniform pressure distribution through curved surface contact. Polyvinyl chloride, TPE, polypropylene, and polyethylene are thermoplastic polymer materials, which can be processed using injection molding or extrusion processes. They achieve deformation recovery ability through material elasticity.

[0050] Specifically, when the pressure-applying part 2 adopts a strip-shaped solid structure, the polypropylene material is injection molded to form a rigid support, generating directional extrusion along the axial direction of the liquid storage part 1 during the pressure application process. When the pressure-applying part 2 adopts a platform-shaped hollow structure, the polyethylene material is blow molded to form a lightweight object, and the multi-faceted contact structure evenly disperses the force during pressure application. When the pressure-applying part 2 adopts a spherical silicone material, the elastic deformation characteristics cause the pressure-applying part 2 to undergo multi-directional deformation after being compressed, pushing the liquid storage part 1 to contract through curved surface contact. Different combinations of shapes and materials can adjust the pressure path according to the shape of the liquid storage cavity 11. For example, the strip-shaped polyvinyl chloride structure is suitable for the circumferential extrusion of the cylindrical liquid storage cavity 11, and the spherical rubber structure is suitable for the multi-point pressure of the garlic-shaped liquid storage cavity 11. By selecting a combination scheme of thermoplastic and elastic materials, the functionality of the pressure-applying part 2 is guaranteed while reducing the processing difficulty.

[0051] The raised strip 23 is a strip-shaped protrusion structure provided on the side wall surface of the pressure application part 2. It can be implemented by molding or bonding processes. The raised part forms multiple points of contact with the surface of the liquid storage part 1, increasing the contact area and friction between the pressure application part 2 and the liquid storage part 1. The raised strip 23 is made of polyethylene foam, rubber or silicone. Specifically, it can be made of foamed polyethylene, natural rubber or thermosetting silicone. The elasticity and deformation capacity of the material itself can adapt to the shape changes of the liquid storage part 1 during the extrusion process.

[0052] Specifically, when the pressure-applying part 2 applies pressure to the liquid storage part 1, the protrusion 23 and the surface of the liquid storage part 1 are locally squeezed. The elastic material deforms under pressure, filling the gap between the pressure-applying part 2 and the liquid storage part 1, forming a continuous contact area. During the squeezing process, the elastic restoring force of the protrusion 23 can maintain the tight fit of the contact surfaces, avoiding uneven pressure transmission caused by the deformation of the liquid storage part 1, thereby ensuring that the flushing fluid in the liquid storage cavity 11 is squeezed out evenly.

[0053] The injection head 3 is tubular, and a flexible membrane is provided inside the injection head 3. The flexible membrane has dot-shaped, straight, cross-shaped or star-shaped slits 311. The injection head 3 is provided with a push handle 33 for pushing operation during the operation of the flushing device.

[0054] The flexible membrane is a thin-layer structure made of elastic material, specifically silicone or thermoplastic elastomer. It closes naturally through pre-defined slits 311, forming a liquid barrier. The dotted, linear, cross-shaped, or star-shaped slits 311 are specific opening shapes formed by cutting the surface of the flexible membrane, which can be achieved through laser cutting or molding processes. Different slit 311 shapes correspond to different opening pressure thresholds and liquid flow control requirements. The push handle 33 is an operating component located outside the injection head 3. It can be integrally molded with the injection head 3 using injection molding or assembled separately, providing a force fulcrum to assist in the connection operation between the flushing device and the catheter.

[0055] Specifically, in its natural state, the flexible membrane maintains a seal through the closing characteristics of the slits 311, preventing leakage of flushing fluid and intrusion of external contaminants. When the reservoir 11 is pressurized, the flexible membrane expands directionally along the shape of the slits 311 under liquid pressure, forming a controllable liquid channel. The cross-shaped or star-shaped slits 311 reduce opening pressure through multi-directional slit design, while the dotted slits 311 enhance the sealing strength in the closed state by concentrating stress. The push handle 33 increases the operating contact area, enabling medical personnel to apply uniform pushing force when inserting the catheter, avoiding unstable connection due to improper force application.

[0056] The injection head 3 has a check ring 32 inside, which is positioned between the flexible membrane and the reservoir 11, and is close to the flexible membrane. The check ring 32 is annular or Venturi tube shaped. The check ring 32 is a ring-shaped rigid or semi-rigid component, which can be made of medical-grade polypropylene and is installed near the flexible membrane by integral molding with the injection head 3, embedding into the inner wall of the injection head 3, or snap-fit ​​fixing.

[0057] The function of the check ring 32 is to limit the deformation direction of the flexible membrane: when the flushing fluid in the reservoir 11 applies positive pressure to the flexible membrane (i.e., from the direction of the reservoir 11 to the direction of the injection head 3 outlet), the slit 311 of the flexible membrane opens in the direction of liquid discharge, and the flushing fluid is discharged through the slit 311; when external liquid (such as blood) applies reverse pressure to the flexible membrane (i.e., from the direction of the injection head 3 outlet to the direction of the reservoir 11), the flexible membrane is restricted by the check ring 32 and cannot be turned inward, the slit 311 remains closed, and the liquid flows back.

[0058] The injection head 3 is equipped with a sealing cap 4 that is detachably connected to it. This can be achieved through threaded connection, snap-fit ​​engagement, or elastic sleeve connection. For example, an external thread can be provided on the outer wall of the injection head 3, and a corresponding internal thread can be provided on the inner wall of the sealing cap 4. A seal is achieved by tightening the thread. The sealing cap 4 is an independent component covering the port of the injection head 3. It can be made of polyethylene, polypropylene, or silicone. For instance, silicone can be used to form an elastic sleeve structure, which, through elastic deformation, tightly adheres to the outer wall of the injection head 3, achieving physical isolation.

[0059] Specifically, in the non-use state, the sealing cap 4 covers the injection head 3 port through a threaded connection or snap-fit, forming a physical barrier to prevent external contaminants from contacting the flushing fluid. During use, the sealing cap 4 is removed by rotating or pressing to expose the injection head 3 port for flushing and sealing. The design of the sealing cap 4 allows for disassembly and reassembly without destructive opening, enabling repeated opening and closing. Furthermore, the selection of materials and structural design ensures reliable sealing.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any ordinary changes and substitutions made by those skilled in the art within the scope of the technical solution of the present invention should be included within the protection scope of the present invention.

Claims

1. A pre-filled catheter flushing device, comprising a reservoir and an injection head, characterized in that, The liquid storage container includes a liquid storage section and a pressurizing section. The liquid storage section includes a storage chamber for storing flushing fluid, and the pressurizing section is used to compress the liquid storage section. The liquid storage section is deformable. The injection head is connected to the liquid storage section and communicates with the liquid storage chamber.

2. The pre-filled catheter flushing device according to claim 1, characterized in that, The cross-section of the liquid storage cavity is rectangular, trapezoidal, triangular, or circular. The pressure application section includes a plurality of extrusion members arranged around the liquid storage section. Each extrusion member includes an air-filled extrusion chamber and is deformable.

3. A pre-filled catheter flushing device according to claim 2, characterized in that, The plurality of extrusion components are fixed to the liquid storage section.

4. A pre-filled catheter flushing device according to claim 2, characterized in that, A connecting member is connected between two adjacent extrusion members, and the connecting member is fixed to the liquid storage part.

5. A pre-filled catheter flushing device according to claim 1, characterized in that, The liquid storage section is garlic-shaped and includes a recessed space. One end of the pressure-applying part extends into the recessed space and cooperates with the liquid storage section.

6. A pre-filled catheter flushing device according to claim 5, characterized in that, The pressure-applying part is strip-shaped, platform-shaped, or spherical.

7. A pre-filled catheter flushing device according to claim 6, characterized in that, The side wall of the pressure-applying part is also provided with several protrusions that correspond to and cooperate with the liquid storage part.

8. A pre-filled catheter flushing device according to claim 3 or 4, characterized in that, One end of the extrusion member extends toward the injection head, and the other end of the extrusion member extends out of the liquid storage section.

9. A pre-filled catheter flushing device according to claim 7, characterized in that, The injection head is tubular, and a flexible membrane is provided inside the injection head. The flexible membrane has dot-shaped, straight, cross-shaped or star-shaped slits.

10. A pre-filled catheter flushing device according to claim 9, characterized in that, The injection head is equipped with a sealing cap that can be detachably connected to it.

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