CN110774522B

CN110774522B - Enhanced medical cannula and forming method thereof

Info

Publication number: CN110774522B
Application number: CN201910574429.4A
Authority: CN
Inventors: 郑剑波; 刘志军; 马奔; 魏信鑫; 袁栋平
Original assignee: Dongguan Kewei Medical Instrument Co Ltd
Current assignee: Dongguan Kewei Medical Instrument Co Ltd
Priority date: 2019-06-28
Filing date: 2019-06-28
Publication date: 2022-06-14
Anticipated expiration: 2039-06-28
Also published as: CN110774522A

Abstract

The invention discloses an enhanced medical cannula and a forming method thereof, wherein the forming method of the enhanced medical cannula comprises the following steps: providing raw materials, a curing agent, a reinforcing structure and a forming mold; uniformly mixing the raw materials with a curing agent to form mixed liquid; arranging the reinforcing structure in a forming die; injecting the mixed liquid into a forming die; the mixed liquid is solidified in the forming mold and combined with the reinforcing structure. According to the forming method of the enhanced medical cannula, the raw materials can be cured under the action of the curing agent, so that repeated operations of plastic dipping and baking are avoided, the enhanced medical cannula can be formed at one time, the forming efficiency is greatly improved, and the production cost is reduced.

Description

Enhanced medical cannula and forming method thereof

Technical Field

The invention relates to the technical field of medical cannulas, in particular to an enhanced medical cannula and a forming method thereof.

Background

At present, the reinforced medical cannula is formed by a few optional methods, and is formed by a dip molding method generally. Dipping plastic molding is to dip the mandrel into the material liquid of the molding enhanced medical cannula, then baking the mandrel dipped with the material liquid on the surface to plasticize the material liquid, and forming the basic pipe fitting by repeating the steps of dipping the material liquid and heating and plasticizing. Then the reinforcing rib is sleeved on the manufactured basic tube body, the basic tube body sleeved with the reinforcing rib is immersed in the material liquid of the formed enhanced medical intubation tube, then the basic tube body with the surface dipped with the material liquid and the reinforcing rib are baked to plasticize the material liquid, and the enhanced medical intubation tube is formed by repeating the steps of dipping the material liquid and heating and plasticizing.

Use and dip in moulding's shaping mode needs a lot of repeatedly dip in, add the thermal plasticization, complex operation, owing to use and dip in moulding's shaping mode shaping, need slow down speed as far as possible when dipping in the emulsion, avoid the unable thorough cladding strengthening rib of emulsion, produce the bubble in avoiding the body after the plastify, lead to the shaping inefficiency, high in production cost, consequently, how to reduce to dip in the number of times as far as possible and avoid using even to dip in moulding mode and obtain the medical intubate of enhancement mode and become the problem of waiting urgently to solve.

Disclosure of Invention

The embodiment of the invention provides a reinforced medical cannula and a forming method thereof, and aims to solve the problems of low efficiency and high cost of forming the reinforced medical cannula by using the existing forming method.

In order to solve the technical problem, the invention provides a method for forming an enhanced medical cannula, which comprises the following steps: providing raw materials, a curing agent, a reinforcing structure and a forming mold; uniformly mixing the raw materials with a curing agent to form mixed liquid; arranging the reinforcing structure in a forming die; injecting the mixed liquid into a forming die; the mixed liquid is solidified in the forming die and combined with the reinforcing structure; the molding die is removed.

According to an embodiment of the present invention, the step of uniformly mixing the raw material and the curing agent to form the mixed liquid further includes the steps of: heating the raw materials and the curing agent in the mixing process of the raw materials and the curing agent.

According to an embodiment of the present invention, the mixed liquid is solidified in the forming mold, and in the step of combining with the reinforcing structure, the forming mold is heated during the solidification of the mixed liquid, so that the mixed liquid is heated.

According to an embodiment of the present invention, the reinforcing structure has a first tube layer and a reinforcing rib, the reinforcing rib is disposed on a surface of the first tube layer, after the step of curing the mixed liquid in the forming mold and combining with the reinforcing structure, the mixed liquid added into the forming mold is cured into a second tube layer, and the second tube layer is combined with the first tube layer into a whole and covers the reinforcing rib.

According to an embodiment of the present invention, the first tube layer is provided by extrusion or dip molding through an extruder.

According to an embodiment of the present invention, the reinforcing structure is a rib, and further includes, after the step of injecting the mixed liquid into the molding die, the steps of: and the mixed liquid added into the forming die coats the reinforcing ribs.

According to an embodiment of the present invention, the rib is a wire spring or a leaf spring.

According to an embodiment of the present invention, the raw material is a polyurethane prepolymer.

According to an embodiment of the present invention, the curing agent is one or more of diamine curing agent, alcohol amine curing agent and small molecule polyol curing agent.

The invention provides a reinforced medical cannula which is formed by using the forming method of the reinforced medical cannula.

In the embodiment of the invention, the forming method of the enhanced medical cannula uniformly mixes the raw material and the curing agent, then the mixed liquid of the raw material and the curing agent is added into the forming die with the reinforcing structure, and the mixed liquid is combined with the reinforcing structure after being cured to form the enhanced medical cannula of the invention.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiment(s) of the invention and together with the description serve to explain the invention without limiting the invention. In the drawings:

FIG. 1 is a schematic illustration of a method of forming a reinforced medical cannula according to a first embodiment of the present invention;

FIG. 2 is a cross-sectional view of a reinforced medical cannula forming die in accordance with a first embodiment of the present invention;

FIG. 3 is an enlarged view of area A of FIG. 2;

FIG. 4 is an enlarged view of area B of FIG. 2;

FIG. 5 is a cross-sectional view of the bottom holder and the top holder of the reinforced medical cannula molding die of the first embodiment of the present invention;

FIG. 6 is an enlarged view of area C of FIG. 2;

FIG. 7 is a schematic view of a mold for forming a reinforced medical cannula according to a second embodiment of the present invention;

FIG. 8 is a cross-sectional view of a reinforced medical cannula mold of a second embodiment of the present invention;

FIG. 9 is an enlarged view of area D of FIG. 8;

fig. 10 is an enlarged partial view of a mold for forming a reinforced medical cannula according to a second embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are one embodiment of the present invention, and not all embodiments of the present invention. All other embodiments obtained by a person skilled in the art based on the embodiments of the present invention without any creative work belong to the protection scope of the present invention.

Please refer to fig. 1, fig. 2, fig. 3 and fig. 4, which are a schematic diagram of a molding method of an enhanced medical cannula, a sectional view of a molding mold, and enlarged views of an area a and an area B in fig. 2 according to a first embodiment of the present invention. As shown in the drawing, the method of molding the reinforced medical cannula 1 according to the present embodiment first performs step S11: providing raw materials, a curing agent, a reinforcing structure 10 and a forming mold 2; step S13 is executed again: uniformly mixing the raw materials with a curing agent to form mixed liquid; then, step S15 is executed again: arranging the reinforcing structure 10 in the forming mould 2; step S17 is then executed: injecting the mixed liquid into a forming die 2; then, step S19 is executed: the mixed liquid is solidified in the forming die 2 and combined with the reinforcing structure; finally, step S21 is executed: the molding die 2 is removed. The solidified mixed liquid is integrated with the reinforcing structure 10 to form the reinforced medical cannula 1 of the present embodiment.

In step S11, the raw material is a polyurethane prepolymer, which specifically includes a terminal isocyanate group prepolymer, a terminal hydroxyl group prepolymer, a prepolymer containing a blocking group, and a polyurethane prepolymer containing other groups (such as a terminal silane group and a terminal alkyl acrylate), and in this embodiment, one or more of the raw materials may be selected. The curing agent comprises diamine curing agent, alcohol amine curing agent and micromolecular polyalcohol curing agent, wherein the diamine curing agent can be 3,3 '-dichloro-4, 4' -diaminodiphenylmethane (MOCA), the alcohol amine curing agent can be Triisopropanolamine (TIPA), the micromolecular polyalcohol curing agent can be Trimethylolpropane (TMP) and the like.

In step S13, the mixing ratio of the raw material and the curing agent can be 3:1, 2:1, etc., and the specific mixing ratio of the raw material and the curing agent depends on the desired product because different mixing ratios can form products with different hardness.

In the embodiment, the raw material is isocyanate-terminated prepolymer, and the curing agent is Triisopropanolamine (TIPA). When the raw materials and the curing agent are mixed, the raw materials and the curing agent are taken according to the ratio of 3:1 and put into a container, and the raw materials and the curing agent are uniformly mixed by stirring or other mixing modes to form mixed liquid.

Preferably, the container for containing the raw materials and the curing agent is a heatable container, and in the process of mixing the raw materials and the curing agent, the container is heated, so that the raw materials and the curing agent are heated in the mixing process, the mixing of the raw materials and the curing agent is accelerated, and the mixing uniformity of the raw materials and the curing agent is improved.

In step S15, the reinforcing structure 10 is set in the molding die 2, and the reinforcing structure 10 is set in the cavity 20 of the molding die 2. In detail, the forming mold 2 provided in step S10 includes an inner core 21, an outer tube 22, a bottom holder 23, and a top holder 24, the outer tube 22 is sleeved outside the inner core 21, a gap is left between an inner surface of the outer tube 22 and an outer surface of the inner core 21, one end of the inner core 21 and one end of the outer tube 22 sleeved together are embedded in the bottom holder 23, the other end is embedded in the top holder 24, a space surrounded by the inner core 21, the outer tube 22, the bottom holder 23, and the top holder 24 is a cavity 20, and a shape of the cavity 20 is the same as a shape of the reinforced medical cannula 1 to be formed.

When step S15 is executed, step S151 is executed first: opening the top retainer 24; then, the substep S152 is executed: placing the reinforcing structure 10 in the cavity 20; then, the substep S153 is performed: the top retainer 24 is pulled back over the inner core 21 and outer tube 22.

When step S17 is executed, the mixed liquid is also injected into the cavity 20 of the molding die 2, specifically, the molding die 2 further includes a glue inlet channel 25, the glue inlet channel 25 penetrates through the bottom holder 23 or the top holder 24 to communicate with the cavity 20, and the mixed liquid can be injected into the cavity 20 through the glue inlet channel 25. In the present embodiment, the glue inlet channel 25 is preferably arranged in the bottom holder 23. The outer tube 22 is made of glass, the pouring condition of the mixed liquid can be observed in real time through the outer tube 22, and then the pouring can be stopped in time when the liquid level of the mixed liquid rises to a set height.

Since the reinforcing structure 10 occupies a part of the cavity 20 near the inner core 21 or the outer tube 22 when the substep S152 is completed, the mixed liquid enters the cavity 20 when the substep S17 is performed, the liquid level of the mixed liquid rises from the bottom space of the cavity 20, and the mixed liquid gradually fills the other space of the cavity 20 except the space occupied by the reinforcing structure 10 and covers one side surface of the reinforcing structure 10 during the process of exhausting the air inside the cavity 20 from the bottom to the top. When the above substep S152 is completed, if the reinforcing structure 10 is disposed in the cavity 20 on the side close to the core 21, the injected mixed liquid fills the space in the cavity 20 on the side close to the outer tube 22 and covers the surface of the reinforcing structure 10 close to the outer tube 22; conversely, if the reinforcing structure 10 is disposed in the cavity 20 on the side close to the outer tube 22, the injected mixed liquid fills the space in the cavity 20 on the side close to the inner core 21 and covers the surface of the reinforcing structure 10 close to the inner core 21.

Specifically, the reinforcement structure 10 of the present embodiment includes a first tube layer 101 and a reinforcing rib 102 disposed on the inner/outer surface of the first tube layer 101. If the reinforcing structure 10 is disposed on the side of the cavity 20 close to the inner core 21, the reinforcing rib 102 is sleeved on the outer surface of the first tube layer 101, when the reinforcing structure 10 is disposed in the cavity 20, the inner surface of the first tube layer 101 is closely attached to the side surface of the inner core 21, the position where the glue inlet channel 25 is communicated with the cavity 20 is on the side of the cavity 20 close to the outer tube 22, and when the mixed liquid enters the cavity 20 from the glue inlet channel 25, the mixed liquid gradually covers the exposed part of the reinforcing rib 102 and the surface of the first tube layer 101 facing the outer tube 22. Conversely, if the reinforcing structure 10 is disposed on the side of the cavity 20 close to the outer tube 22, the reinforcing rib 102 is disposed on the inner surface of the first tube layer 101, when the reinforcing structure 10 is disposed in the cavity 20, the outer surface of the first tube layer 101 is closely attached to the inner surface of the outer tube 22, the position of the glue inlet channel 25 communicated with the cavity 20 is on the side of the cavity 20 close to the inner core 21, and when the mixed liquid enters the cavity 20 from the glue inlet channel 25, the mixed liquid gradually covers the exposed portion of the reinforcing rib 102 and the exposed portion of the inner surface of the first tube layer 101.

The reinforced medical cannula 1 to be formed may be a straight tube, a reducer tube, a femoral artery cannula, a femoral vein cannula, or other medical tubes, and the reinforcing rib 102 may be a linear spring, a leaf spring, or a connection body of a linear spring and a leaf spring.

In step S19, the mixed liquid is solidified in the forming mold 2, and in combination with the reinforcing structure 10, the mixed liquid can be solidified in a normal temperature environment to form the second tube layer 11. The second tube layer 11, the first tube layer 101 and the reinforcing rib 102 are integrated, that is, the reinforcing rib 102 is completely covered by the second tube layer 11 and the first tube layer 101, so as to form the enhanced medical cannula 1 of the present embodiment.

Preferably, the outer tube 22 is baked during the curing process of the mixed liquid, and the outer tube 22 is a heat conducting member for conducting heat to the mixed liquid, so that the mixed liquid is heated to accelerate the curing speed of the mixed liquid. Of course, the glass selected for the outer tube 22 is heat-resistant glass or stainless steel, and the heat-resistant temperature is higher than the heating temperature.

Specifically, the temperature of the heating outer tube 22 is below 150 ℃, and the heating is continued until the mixed liquid is completely solidified. In addition, the raw materials in the mixed liquid can be cured in a photocuring mode, and when the raw materials are cured in the photocuring mode, the curing agent is a photosensitizer.

After step S19 is completed, the forming mold 2 is cooled, the solidified mixed liquid in the forming mold 2 is shaped, and step S21 is finally performed to remove the forming mold 2, so as to obtain the enhanced medical cannula 1 of the present embodiment.

The structure of the forming mold is described in detail below, referring to fig. 5 and 6, which are cross-sectional views of the bottom holder and the top holder of the forming mold for the reinforced medical cannula according to the first embodiment of the present invention and an enlarged view of the area C in fig. 2. As shown in the drawing, in the forming die 2 of the present embodiment, the surface of the bottom holder 23 facing the top holder 24 is provided with a first outer tube fixing groove 231, the groove bottom of the first outer tube fixing groove 231 is provided with a first core fixing groove 232, and the shape of the cross section of the first outer tube fixing groove 231 is the same as the shape of the cross section of the end of the outer tube 22, and the shape of the cross section of the first core fixing groove 232 is the same as the shape of the cross section of the end of the core 21. One end of the outer tube 22 is inserted into the first outer tube fixing groove 231, and one end of the inner core 21 is inserted into the first inner core fixing groove 232. The glue inlet channel 25 penetrates through the bottom holder 23 along the axial direction of the inner core 21, that is, the glue inlet of the glue inlet channel 25 is arranged at the bottom of the first inner core fixing groove 232.

Correspondingly, the surface of the top holder 24 facing the bottom holder 23 is provided with a second outer tube fixing groove 241, the groove bottom of the second outer tube fixing groove 241 is provided with a second core fixing groove 242, and the shape of the cross section of the second outer tube fixing groove 241 is the same as the shape of the cross section of the other end portion of the outer tube 22, and the shape of the cross section of the second core fixing groove 242 is the same as the shape of the cross section of the other end portion of the core 21. The other end of the outer tube 22 is inserted into the second outer tube fixing groove 241, and the other end of the inner core 21 is inserted into the second inner core fixing groove 242, that is, the inner core 21 penetrates through the outer tube 22, and both ends of the inner core 21 protrude from the outer tube 22, respectively. The arrangement of the first outer tube fixing grooves 231, the first core fixing grooves 232, the second outer tube fixing grooves 241 and the second core fixing grooves 242 enables the core 21 and the outer tube 22 to be accurately embedded into the bottom fixer 23, and also ensures the top fixer 24 to be accurately sleeved on the core 21 and the outer tube 22, thereby rapidly completing the assembly of the core 21, the outer tube 22, the bottom fixer 23 and the top fixer 24.

Preferably, a sealing member 243 is further disposed in the gap between the outer tube 22 and the second outer tube fixing groove 241 to prevent the mixed liquid from flowing out from the gap between the outer tube 22 and the second outer tube fixing groove 241 to affect the molding of the reinforced medical cannula 1 when the step S15 is executed.

Further, the forming mold 2 further includes a first sleeve 26 and a second sleeve 27. The first sleeve 26 has one end fitted over the side surface of the bottom holder 23 and the other end extending in a direction close to the top holder 24 and extending to the outer surface of the outer tube 22. The second sleeve 27 has one end fitted over the side surface of the top retainer 24 and the other end extending in a direction toward the bottom retainer 23 and extending to the outer surface of the outer tube 22. That is, the first sleeve 26 covers the joint between the bottom holder 23 and the outer tube 22, the second sleeve 27 covers the joint between the top holder 24 and the outer tube 22, and the first sleeve 26 and the second sleeve 27 are both soft rubber sleeves, so that the inner core 21 and the outer tube 22 can be further ensured to be stable between the bottom holder 23 and the top holder 24.

Referring to fig. 7, 8 and 9, there are shown a schematic view, a sectional view and an enlarged view of a region D in fig. 8 of a mold for forming an enhanced medical cannula according to a second embodiment of the present invention. As shown in the drawings, the forming die 2 of the present embodiment is different from the forming die of the first embodiment in that the forming die 2 of the present embodiment further includes a vacuum structure 28, both ends of the vacuum structure 28 are respectively sleeved on the side surfaces of the bottom holder 23 and the top holder 24, and the inner core 21 and the outer tube 22 between the bottom holder 23 and the top holder 24 are enclosed in the inner space thereof. Before step S15 is executed, the internal space of the vacuum structure 28 is vacuumized to make the space in the cavity 20 in a vacuum state, so as to avoid that the air cannot be completely removed by the mixed liquid when step S15 is executed, and the air is left in the dead angle between the first tube layer 101 and the reinforcing rib 102, thereby avoiding the existence of air bubbles between the cured second tube layer 11 and the first tube layer 101 as well as the reinforcing rib 102, and effectively ensuring the quality of the formed enhanced medical cannula 1.

Specifically, the vacuum structure 28 includes a bottom cover 280, a top cover 281, and a tube 282 disposed between the bottom cover 280 and the top cover 281, wherein the bottom cover 280, the top cover 281, and the tube 282 are hermetically connected to enclose an inner space of the vacuum structure 28. The bottom hole and the top hole are respectively opened on the opposite surfaces of the bottom cover 280 and the top cover 281, and the bottom hole and the top hole are step holes, and the bottom retainer 23 and the top retainer 24 are correspondingly clamped in the bottom hole and the top hole, so as to respectively fix the bottom retainer 23 and the top retainer 24 in the bottom cover 280 and the top cover 281, and simultaneously fix the inner core 21 and the outer tube 22 in the inner space of the vacuum structure 28.

Further, the vacuum structure 28 further includes at least one vacuum nozzle 283, in the present embodiment, the number of the vacuum nozzles 283 is two, and the two vacuum nozzles 283 respectively penetrate through the bottom cover 280 and the top cover 281 and are communicated with the inner space of the vacuum structure 28, and are respectively disposed in a staggered manner with the bottom hole and the top hole. The interior of the vacuum structure 28 may be evacuated by the evacuation nipple 283.

Preferably, sealing rings 29 are further provided between the bottom hole and the bottom holder 23 and between the top hole and the top holder 24, respectively, to ensure the overall sealing of the vacuum structure 28.

Preferably, the tube 282 is made of acrylic transparent material so that the condition in the cavity 20 can be observed through the tube 282.

Referring to fig. 10, a partial enlarged view of a mold for forming a reinforced medical cannula according to a second embodiment of the present invention is shown. As shown in the drawings, the vacuum structure 28 of the present embodiment further includes a locking component 284, and the locking component 284 is disposed on the surface of the top cover 281 away from the bottom cover 280 for locking the top holder 23 and fixing the position of the top holder 23 in the vacuum structure 28, while ensuring the sealing performance of the forming mold 2 of the present embodiment.

Specifically, the locking assembly 284 comprises a locking tab 2840 and a connecting member 2841, wherein one end of the locking tab 2840 is movably connected to the top cover 281 through the connecting member 2841, so that the locking tab 2840 can be rotatably moved relative to the top cover 281 and the top holder 24. And, the middle portion of the locking piece 2840 has a notch corresponding to an end of the top holder 24 far away from the bottom holder 23, when the locking piece 2840 rotates and rotates to a locking position where an end of the top holder 24 far away from the bottom holder 23 is located in the notch of the middle portion, another connecting piece 2841 is used to connect the locking piece 2840 with the bottom cover 280 to fix the position of the locking piece 2840, and further fix the position of the top holder 24 in the top cover 281.

In this embodiment, the two connecting members 2841 are screws, the two ends of the locking piece 2840 have openings or notches adapted to the two connecting members 2841, and the top cover 281 is provided with corresponding screw holes, which do not penetrate through the top cover 281. Before the stay 2840 rotates to the locking position, the screw of stay 2840 one end is not screwed up completely, so that the stay 2840 can rotate, after the stay 2840 rotates to the locking position, the screw at the both ends of stay 2840 is screwed up completely, in order when the position of fixed top fixer 24 in top cap 281, compress the clearance between top fixer 24 and the apical pore and the clearance between bottom fixer 23 and the bottom hole, make top fixer 24 and apical pore can closely laminate with the tight 29 of sealing washer, also make bottom fixer 23 and bottom hole closely laminate with another sealing washer 29, ensure the leakproofness of forming die 2 of this embodiment.

In using the molding die 2 of the present embodiment, before performing step S15, the top holder 24 is taken out of the top hole, the reinforcing structure 10 is placed in the cavity 20, the top holder 24 is placed in the top hole, and the top holder 24 is locked by the locking assembly 284. Before the step S17 is performed, the internal space of the molding die 2 needs to be evacuated, and then the step S17 is performed to pour the mixed liquid into the cavity 20 of the molding die 2.

Preferably, if the curing of the mixed solution is accelerated by heating in step S19, a plurality of infrared baking lamps may be uniformly disposed on the inner surface of the pipe 282, and the infrared baking lamps extend along the axial direction of the outer pipe 22 to bake the outer pipe 22 in a covering manner. Of course, the wiring hole provided with the infrared baking lamp may be provided on the bottom cover 280, and the wiring hole may be sealed by a rubber stopper or a sealant to ensure sealability.

After the step S19 is completed, the top fixer 24 is opened after the outer tube 22 is cooled, the inner core 21, the outer tube 22 and the formed reinforced medical cannula 1 are taken out together, and after the reinforced medical cannula 1 is completely cooled and shaped, the reinforced medical cannula 1 is taken out from the inner core 21 and the outer tube 22.

In the embodiment, since step S19 is performed in a vacuum environment, when pouring the mixed liquid into the cavity 20, the mixed liquid can be poured quickly without considering the influence of air, and the molding efficiency of the reinforced medical cannula 1 can be improved.

In the third embodiment of the present invention, the reinforcing structure 10 is only the reinforcing ribs 102, i.e., the first tube layer is omitted. The mold 2 of the present embodiment is used in the same manner as the mold of the second embodiment, however, the position of the rib 102 in the cavity 20 is ensured to be located between the inner core 21 and the outer tube 22 when the rib 102 is placed in the cavity 20, so that after step S19 is completed, the rib 102 is located in the solidified mixed liquid to prevent the rib 102 from being exposed on the surface of the solidified mixed liquid, thereby ensuring the quality of the formed reinforced medical cannula 1.

Specifically, a positioning groove (not shown) is provided in the bottom of the first outer tube fixing groove 231 of the bottom holder 23, and the positioning groove is located at the periphery of the first core fixing groove 232. When one end of the core 21 is inserted into the first core fixing groove 232 and one end of the outer tube 22 is inserted into the first outer tube fixing groove 231, the positioning groove is located between the core 21 and the outer tube 22 and communicates with the cavity 20. When the reinforcing bars 102 are placed in the cavity 20, one end of the reinforcing bars 102 are inserted into the positioning grooves to ensure that the reinforcing bars 102 are entirely positioned between the inner core 21 and the outer tube 22.

After the mixed liquid is solidified and cooled, it is taken out in the forming mold, and a portion thereof formed in the positioning groove is cut off to obtain the reinforced medical cannula 1 of the present embodiment.

In summary, according to the forming method of the enhanced medical cannula provided by the invention, the uniformly mixed raw materials and the curing agent are added into the forming mold provided with the reinforcing structure, and the raw materials are combined with the reinforcing structure after being cured under the action of the curing agent, so that the enhanced medical cannula is formed.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A molding method of an enhanced medical cannula is characterized by comprising the following steps:

providing raw materials, a curing agent, a reinforcing structure and a forming mold;

uniformly mixing the raw materials with the curing agent to form mixed liquid;

disposing the reinforcing structure within the forming mold;

injecting the mixed liquid into the molding die;

the mixed liquid is solidified in the forming die and combined with the reinforcing structure;

removing the forming die;

the forming die comprises an inner core, an outer tube, a bottom fixer and a top fixer, the outer tube is sleeved outside the inner core, a gap is reserved between the inner surface of the outer tube and the outer surface of the inner core, the inner core and one end of the outer tube which are sleeved together are embedded in the bottom fixer, the other end of the inner core and one end of the outer tube are embedded in the top fixer, and the inner core, the outer tube, the bottom fixer and the top fixer enclose a cavity; the outer tube is made of glass;

the forming die further comprises a vacuum structure, the vacuum structure comprises a bottom cover, a top cover and a tube body arranged between the bottom cover and the top cover, and the bottom cover, the top cover and the tube body are hermetically connected to enclose an inner space of the vacuum structure; the vacuum structure also comprises at least one vacuumizing connector, and the internal space of the vacuum structure is vacuumized through the vacuumizing connector; the tube body is made of an acrylic transparent tube;

the forming die further comprises a first sleeve and a second sleeve, the first sleeve covers the joint of the bottom fixer and the outer tube, the second sleeve covers the joint of the top fixer and the outer tube, and the first sleeve and the second sleeve are both soft rubber sleeves;

a bottom hole and a top hole are respectively formed in the surfaces of the bottom cover opposite to the top cover, and sealing rings are respectively arranged between the bottom hole and the bottom fixer and between the top hole and the top fixer;

the vacuum structure further comprises a locking assembly, the locking assembly comprises a locking sheet and a connecting piece, one end of the locking sheet is movably connected with the top cover through the connecting piece, and the locking sheet can rotate and move relative to the top cover and the top fixer; and the middle part of the locking sheet is provided with a notch corresponding to one end of the top fixer far away from the bottom fixer, when the locking sheet rotates and rotates to a locking position in the notch at the middle part of the top fixer, the other connecting piece is used for locking the locking sheet and the bottom cover to fix the position of the locking sheet and further fix the position of the top fixer in the top cover.

2. The method of forming an enhanced medical cannula according to claim 1, wherein in the step of uniformly mixing the raw material with the solidifying agent to form a mixed liquid, the method further comprises the steps of: and heating the raw material and the curing agent in the mixing process of the raw material and the curing agent.

3. The method of forming an enhanced medical cannula according to claim 1, wherein in the step of solidifying the mixed liquid in the forming mold and combining with the reinforcing structure, further comprising the steps of: and heating the forming die in the process of curing the mixed liquid to heat the mixed liquid.

4. The method of claim 1, wherein the reinforcement structure has a first tube layer and a reinforcement rib disposed on a surface of the first tube layer, and wherein the mixed liquid introduced into the mold is solidified into a second tube layer integrated with the first tube layer and covering the reinforcement rib in the step of solidifying the mixed liquid in the mold and combining with the reinforcement structure.

5. The method of forming an enhanced medical cannula of claim 4, wherein the first tube layer is provided by extrusion from an extruder or dip molding.

6. The method of forming an enhanced medical cannula according to claim 1, wherein the reinforcing structure is a reinforcing rib, further comprising the step of, after the step of injecting the mixed fluid into the forming mold: and the mixed liquid added into the forming die coats the reinforcing rib.

7. The method of forming an enhanced medical cannula according to claim 4 or 6, wherein the reinforcing rib is a wire spring or a leaf spring.

8. The method of claim 1, wherein the material is a polyurethane prepolymer.

9. The method of claim 1, wherein the curing agent is one or more of a diamine curing agent, an alcohol amine curing agent, and a small molecular polyol curing agent.

10. A reinforced medical cannula, wherein the reinforced medical cannula is formed using the method of forming a reinforced medical cannula of any of claims 1-9.