Automatic sealing leakproof joint and injector

Abstract

The invention discloses an automatic sealing leakproof connector and an injector, and relates to the technical field of medical instruments. In the automatic sealing leakproof connector, a supporting sleeve is provided with an outer pipe and an inner pipe, the inner pipe is sleeved with the head end of the outer pipe, the hole diameter of the head end of the inner pipe is smaller than that of the tail end of the inner pipe, and a liquid outlet is formed in the end wall of the head end of the inner pipe; the telescopic elastic pipe is arranged in the outer pipe in a sleeved mode, the tail end of the elastic pipe abuts against and supports the tail end of the outer pipe, and an inner pipeline of the elastic pipe is communicated with the tail end of an inner pipeline of the outer pipe. The head end of the elastic tube is provided with an infusion port, can slide in the axial direction and is inserted into the inner tube in a sealing fit mode so as to open or close the infusion port; the switch piece is arranged between the inner tube and the outer tube in a sliding mode in the axial direction, the tail end of the switch piece abuts against the elastic tube, and when the locking connector is inserted into the head end of the supporting sleeve, the locking connector can push the switch piece to move towards the tail end of the supporting sleeve so as to push the elastic tube to slide in the axial direction, and liquid medicine leakage can be effectively prevented when the anti-leakage connector is used for liquid injection.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and more specifically, to an automatic closing and leak-proof joint. In addition, the present invention also relates to a syringe including the above-mentioned automatic closing and leak-proof joint. Background Art

[0002] Hazardous drugs are drugs that can pose a risk or harm of occupational exposure. They have characteristics such as genotoxicity, carcinogenicity, and teratogenicity, and can also refer to drugs that have a harmful effect on fertility and can cause serious organ or other toxicities at low doses, such as anti-tumor drugs.

[0003] In hospitals, the three places with a relatively high risk of hazardous drug exposure are usually the intravenous admixture service center, the operating room, and the ward.

[0004] Specifically, in the intravenous admixture service center, ordinary syringes are currently commonly used to prepare hazardous drugs. Inevitably, drug splashing or leakage will occur during this process. Throughout the process, anti-tumor drugs are very likely to invade the bodies of medical staff through the skin, digestive tract, and respiratory tract.

[0005] In the operating room, for example, in the operation process of transcatheter arterial chemoembolization, in addition to facing the harm from radiation, due to the requirements of the operation, anti-tumor drugs are often prepared and injected during interventional operations. Inevitably, medical staff face anti-tumor drug exposure caused by the volatilization or leakage of anti-tumor drugs during this process.

[0006] In the ward, during the infusion process, screw-thread syringes are commonly used to add drugs through the needleless drug addition port on the infusion device, or needle syringes are used to puncture the injection part on the infusion device to add drugs. When the syringe is separated from the needleless drug addition port or the injection part, it is easier to have the phenomenon of drug volatilization or leakage.

[0007] In summary, how to avoid the leakage of hazardous drugs is an urgent problem to be solved by those skilled in the art at present. Summary of the Invention

[0008] In view of this, the purpose of the present invention is to provide an automatic closing and leak-proof joint, and using this leak-proof joint for liquid injection can effectively prevent the leakage of liquid medicine.

[0009] Another purpose of the present invention is to provide a syringe including the above-mentioned automatic closing and leak-proof joint.

[0010] In order to achieve the above purposes, the present invention provides the following technical solutions:

[0011] An automatic closing and leak-proof joint, comprising:

[0012] Support sleeve, having an outer tube and an inner tube, and the inner tube is sleeved inside the head end of the outer tube. The aperture diameter of the head end of the inner tube is smaller than that of the tail end of the inner tube, and the end wall of the head end of the inner tube has a liquid outlet;

[0013] Elastic tube, which is a telescopic structure and is sleeved inside the outer tube. The tail end of the elastic tube abuts and supports against the tail end of the outer tube, and the inner pipeline of the elastic tube communicates with the tail end of the inner pipeline of the outer tube; The head end of the elastic tube has an infusion port, and the head end of the elastic tube can be axially slid and inserted into the inner tube in a sealing fit to open or close the infusion port;

[0014] Switch member, axially slidably arranged between the inner tube and the outer tube. The tail end of the switch member abuts against the elastic tube, and when the head end of the support sleeve is inserted into the locking joint, the locking joint can push the switch member to move it towards the tail end of the support sleeve to push the elastic tube to slide axially.

[0015] Preferably, the outer tube includes a first support tube and a second support tube;

[0016] The first support tube has a first outer tube and the inner tube, and the inner tube is sleeved inside the head end of the first outer tube. The second support tube has a second outer tube and a second inner tube, and the second inner tube is sleeved inside the head end of the second outer tube. The tail end of the elastic tube is sleeved on the head end of the second inner tube. The outer peripheral surface of the tail end of the second inner tube has a right-handed thread to thread-connect the tail end of the second support tube when rotating an external device in the positive axial direction;

[0017] The head end of the second outer tube is inserted into the tail end of the first outer tube to form the outer tube. Among the second outer tube and the first outer tube, the one on the outer side has a first boss and first clamping portions arranged at intervals along its circumferential direction, and the first clamping portions are located on the side of the first boss close to the tail end of the outer tube; The one on the inner side has a second clamping portion and third clamping portions arranged at intervals along its circumferential direction. The second clamping portion is close to the head end of the outer tube, and the third clamping portion is close to the tail end of the outer tube;

[0018] When the second support tube slides axially to the first position, the second clamping portion abuts against the first end face of the first boss close to the head end of the first outer tube;

[0019] When the second support tube slides axially to the second position, the second clamping portion is away from the first end face of the first boss, and a plurality of the third clamping portions are inserted between the corresponding adjacent first clamping portions, and the third clamping portion abuts against the second end face of the first boss close to the tail end of the first outer tube, so as to limit the positive rotation of the second support tube around the axis and the positive sliding along the axis towards the head end of the first outer tube.

[0020] Preferably, the head end of the second outer tube is inserted into the tail end of the first outer tube, and the outer peripheral surface of the second outer tube is provided with the second clamping portion, the third clamping portion and the second boss, and the second boss is located on one side of the third clamping portion close to the tail end of the second support tube;

[0021] When the second support tube slides axially to the second position, a plurality of the third clamping portions are inserted between the corresponding adjacent first clamping portions, and the third clamping portion abuts against the second end face of the first boss, and the first clamping portion abuts against the third end face of the second boss close to the head end of the second outer tube.

[0022] Preferably, the first boss is an annular boss extending along the circumferential direction of the first outer tube, and the second boss is an annular boss extending along the circumferential direction of the second outer tube.

[0023] Preferably, the tail end of the elastic tube is inserted between the second outer tube and the second inner tube, the middle tube section of the elastic tube is a telescopic hose section, the head end of the second inner tube extends into the conical tube section at the head end of the elastic tube, and the inner pipeline of the inner tube is a conical channel, and the conical tube section can be inserted into the inner part of the inner tube and slide axially;

[0024] The infusion port includes a first infusion port and a second infusion port. The first infusion port is located on the end wall of the conical tube section, and the second infusion port is located on the circumferential surface of the conical tube section. When the conical tube section slides inside the inner tube, the first infusion port can be opened under decompression or closed under pressure, and the second infusion port can be closed by being blocked by the inner tube or opened by being exposed, so as to connect or cut off the inner pipeline of the inner tube and the inner pipeline of the elastic tube.

[0025] Preferably, the first support tube includes a first connecting tube and a second connecting tube. The first connecting tube has a third outer tube and the inner tube. The head end of the second connecting tube is inserted into the tail end of the third outer tube to form the first outer tube. The second connecting tube has the first boss and the first clamping portion;

[0026] Among the tail end of the third outer tube and the head end of the second connecting tube, the inner peripheral surface of the one located on the outside has a positioning groove, and the outer peripheral surface of the one located on the inside has a positioning protrusion. The positioning protrusion is clamped in the positioning groove to limit the relative positional relationship between the first connecting tube and the second connecting tube.

[0027] Preferably, both the first clamping portion and the third clamping portion are right trapezoidal protrusions;

[0028] When the second support tube slides along the first outer tube to the second position, the first plane of the first clamping portion abuts against the third end face of the second boss, and the second plane of the third clamping portion abuts against the second end face of the first boss, so as to limit the forward sliding of the second support tube along the axis towards the head end of the first outer tube;

[0029] When the second support tube is rotated forward, the first vertical plane of the first clamping portion can fit against the second vertical plane of the third clamping portion, so as to limit the forward rotation of the second support tube around the axis;

[0030] When the second support tube is rotated reversely, the first inclined plane of the first clamping portion can slidably fit against the second inclined plane of the third clamping portion, and is used to guide the second support tube to slide reversely along the axis towards the tail end of the first outer tube, so as to withdraw from the first outer tube.

[0031] Preferably, the inner wall of the head end of the outer tube has internal threads for threaded cooperation with the internal locking joint;

[0032] And the head end of the switch member extends to the pipe section of the outer tube having the internal threads.

[0033] Preferably, the switch member has a positioning ring and at least two guiding portions, and several of the guiding portions are installed on the same side of the positioning ring, and the guiding portions extend axially;

[0034] The positioning ring is sleeved and clamped on the elastic tube;

[0035] The connection frame between the inner tube and the outer tube has insertion through holes, and several of the insertion through holes are arranged around the axis, and several of the guiding portions can be slidably inserted into the corresponding insertion through holes, and the free ends of the guiding portions extend to one side of the head end of the outer tube.

[0036] A syringe includes the automatic closing and leak-proof joint according to any one of the above.

[0037] For the automatic closing and leak-proof joint provided by the present invention, the support sleeve is a double-layer sleeve, wherein the inner tube is sleeved inside the head end of the outer tube, the inner diameter of the head end of the inner tube is smaller than the inner diameter of the tail end of the inner tube, and a through hole such as a circular or square hole is provided in the end wall of the head end of the inner tube as the liquid outlet.

[0038] They are cooperatively configured such that an elastic tube is disposed inside an outer tube, and the tail end of the elastic tube abuts against and supports the tail end of the outer tube, so that the tail end of the elastic tube cannot be separated from the tail end of the outer tube, and the head end of the elastic tube can make a telescopic movement by leveraging the tail end of the outer tube as a fulcrum. Moreover, the inner pipeline of the elastic tube is communicated with the tail end of the inner pipeline of the outer tube through the opening at its tail end, so that the liquid medicine injected into the inner pipeline of the outer tube can flow into the inner pipeline of the elastic tube.

[0039] The head end of the elastic tube is inserted inside the inner tube. Since the inner diameter of the head end of the inner tube is smaller than that of the tail end of the inner tube, when the head end of the elastic tube moves along the inner tube towards its head end, the head end of the elastic tube is deformed under pressure or blocked by the inner tube to close the infusion port, so that the liquid medicine in the elastic tube cannot flow into the inner pipeline of the inner tube. When the head end of the elastic tube moves along the inner tube towards its tail end, the head end of the elastic tube is deformed under reduced pressure or exposed in the inner cavity of the inner tube to open the infusion port, so that the liquid medicine in the elastic tube can flow into the inner pipeline of the inner tube and be output through the liquid outlet opened on the end wall of the head end of the inner tube. In addition, the outer wall of the middle sealed tube section of the elastic tube is in interference fit with the inner wall surface of the inner tube for sealing, so that the liquid medicine flowing into the inner tube will not seep between the outer tube and the elastic tube through the gap between the head end of the elastic tube and the inner tube.

[0040] A switch member is provided between the head end of the outer tube and the inner tube. The head end of the switch member extends towards the head end of the outer tube, and the tail end extends towards the tail end of the support sleeve and abuts against the elastic tube. When in use, when the anti-leakage joint is plugged into the locking joint, during the process of inserting the locking joint into the inside of the outer tube, the switch member is pushed to move towards the tail end of the support sleeve, so as to push the head end of the elastic tube towards the tail end of the support sleeve, and the inner pipeline of the elastic tube and the inner pipeline of the inner tube are communicated through the infusion port, so that the liquid medicine can flow through the tail end of the inner pipeline of the outer tube, the inner pipeline of the elastic tube, the infusion port, the inner pipeline of the inner tube and the liquid outlet in sequence to complete the drug injection. On the contrary, after the locking joint is pulled out from the anti-leakage joint, the switch member and the elastic tube lose external force. Thus, under the action of the self-tension of the elastic tube, the head end of the elastic tube moves towards the head end of the support sleeve pipe, closing the infusion port and effectively preventing the leakage of the liquid medicine. Description of the Drawings

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings described below are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the provided drawings.

[0042] Figure 1 It is a cross-sectional view of a specific embodiment provided by the present invention;

[0043] Figure 2Schematic diagram of the first connecting pipe of the specific embodiment provided by the present invention;

[0044] Figure 3 Schematic diagram of the first connecting pipe of the specific embodiment provided by the present invention from another angle;

[0045] Figure 4 Schematic diagram of the first connecting pipe of the specific embodiment provided by the present invention from yet another angle;

[0046] Figure 5 Cross-sectional view of the first connecting pipe of the specific embodiment provided by the present invention;

[0047] Figure 6 Schematic diagram of the switch member of the specific embodiment provided by the present invention;

[0048] Figure 7 Schematic diagram of the elastic tube of the specific embodiment provided by the present invention;

[0049] Figure 8 Cross-sectional view of the elastic tube of the specific embodiment provided by the present invention;

[0050] Figure 9 Schematic diagram of the second connecting pipe of the specific embodiment provided by the present invention;

[0051] Figure 10 Schematic diagram of the second connecting pipe of the specific embodiment provided by the present invention from another angle;

[0052] Figure 11 Cross-sectional view of the second connecting pipe of the specific embodiment provided by the present invention;

[0053] Figure 12 Schematic diagram of the second support pipe of the specific embodiment provided by the present invention;

[0054] Figure 13 Cross-sectional view of the second support pipe of the specific embodiment provided by the present invention;

[0055] Figure 14 Schematic diagram of another second support pipe of the specific embodiment provided by the present invention.

[0056] Reference numerals:

[0057] 1 - Support sleeve;

[0058] 11 - First support pipe;

[0059] 111 - First connecting pipe; 1111 - Third outer pipe; 11111 - Positioning groove; 11112 - Internal thread; 1112 - Inner pipe; 11121 - Liquid outlet; 1113 - Insertion through hole;

[0060] 112 - Second connecting pipe; 1121 - First boss; 11211 - First end face; 11212 - Second end face; 1122 - First clamping portion; 11221 - First plane; 11222 - First vertical plane; 11223 - First inclined plane; 1123 - Positioning protrusion;

[0061] 12 - Second support pipe; 121 - Second outer pipe; 1211 - Second clamping portion; 1212 - Third clamping portion; 12121 - Second plane; 12122 - Second vertical plane; 12123 - Second inclined plane; 1213 - Second boss; 12131 - Third end face; 1214 - Right - hand thread; 1215 - Connecting tapered pipe section; 122 - Second inner pipe;

[0062] 2 - Elastic tube; 21 - Tapered pipe section; 211 - First infusion port; 212 - Second infusion port; 213 - Annular sealing protrusion; 214 - Annular groove; 22 - Telescopic hose section; 23 - Reinforcing rib;

[0063] 3 - Switching member; 31 - Positioning ring; 32 - Guide portion. Detailed implementation manners

[0064] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0065] The core of the present invention is to provide an automatic - closing leak - proof joint, and using this leak - proof joint for liquid injection can effectively prevent liquid medicine leakage. Another core of the present invention is to provide a syringe including the above - mentioned automatic - closing leak - proof joint.

[0066] Please refer to Figure 1 , the present invention provides an automatic - closing leak - proof joint, including a support sleeve 1, an elastic tube 2, and a switching member 3.

[0067] The support sleeve 1 comprises an outer tube and an inner tube 1112, and the inner tube 1112 is sleeved inside the head end of the outer tube, the aperture of the head end of the inner tube 1112 is smaller than the aperture of the tail end of the inner tube 1112, and the end wall of the head end of the inner tube 1112 has a liquid outlet 11121; the elastic tube 2 is a telescopic structure, and is sleeved inside the outer tube, the tail end of the elastic tube 2 is supported by the tail end of the outer tube, and the inner pipe of the elastic tube 2 is connected to the tail end of the inner pipe of the outer tube; the elastic tube 2 is a telescopic structure, and is sleeved inside the outer tube, the tail end of the elastic tube 2 is supported by the tail end of the outer tube, and the inner pipe of the elastic tube 2 is connected to the tail end of the inner pipe of the outer tube; The head end of the tube 2 has an infusion port, and the head end of the elastic tube 2 can be axially slidable and sealed and inserted into the inner tube 1112 to open or close the infusion port; the switch member 3 is axially slidable between the inner tube 1112 and the outer tube, and the tail end of the switch member 3 abuts against the elastic tube 2. When the head end of the supporting sleeve 1 is inserted into the locking joint, the locking joint can push the switch member 3 to move toward the tail end of the supporting sleeve 1 to push the elastic tube 2 to slide axially.

[0068] like Figure 1 As shown, the support sleeve 1 is a double-layer sleeve, in which the inner tube 1112 is sleeved inside the upper end of the outer tube, the inner diameter of the upper end of the inner tube 1112 is smaller than the inner diameter of the lower end of the inner tube 1112, and the end wall of the upper end of the inner tube 1112 is provided with a circular or square through hole as a liquid outlet 11121.

[0069] It should be noted that the type of the support sleeve 1 is not limited, as long as a double-layer sleeve is used, for example, the outer tube is a cylindrical tube, and the inner tube 1112 is a hexagonal pyramid tube, or the outer tube is a hexagonal prism tube, and the inner tube 1112 is a conical tube, etc. The outer tube and the inner tube 1112 can be connected as a whole by a circular ring structure or a plurality of rod-like structures.

[0070] In coordination, the elastic tube 2 is sleeved inside the outer tube, and the lower end of the elastic tube 2 is supported by the lower end of the outer tube, so that the lower end of the elastic tube 2 cannot be separated from the lower end of the outer tube, and the upper end of the elastic tube 2 can be extended and retracted by using the lower end of the outer tube as a fulcrum, and the inner pipe of the elastic tube 2 is connected to the inner pipe of the lower end of the outer tube through its lower end opening, so that the liquid medicine injected into the inner pipe of the outer tube can flow into the inner pipe of the elastic tube 2.

[0071] The upper end of the flexible tube 2 is provided with an infusion port in the shape of a rectangle or a fusiform, etc., and the upper end of the flexible tube 2 is inserted into the interior of the inner tube 1112. Since the inner diameter of the upper end of the inner tube 1112 is smaller than the inner diameter of the lower end of the inner tube 1112, when the upper end of the flexible tube 2 extends upward along the inner tube 1112, the upper end of the flexible tube 2 is deformed under pressure or blocked by the inner tube 1112 to close the infusion port. Thus, the liquid medicine in the flexible tube 2 cannot flow into the inner pipeline of the inner tube 1112. When the upper end of the flexible tube 2 moves downward along the inner tube 1112, the upper end of the flexible tube 2 is deformed when the pressure is released or exposed in the inner cavity of the inner tube 1112 to open the infusion port. Thus, the liquid medicine in the flexible tube 2 can flow into the inner pipeline of the inner tube 1112 and is output through the liquid outlet 11121 provided on the end wall of the upper end of the inner tube 1112. And the outer wall of the middle sealed pipe section of the flexible tube 2 is in interference fit with the inner wall surface of the inner tube 1112 for sealing. For example Figure 7 the annular sealing protrusion 213 shown. The annular sealing protrusion 213 can be sealed and connected to the structure on the flexible tube 2 by means such as bonding or injection molding. And the infusion port is located above the above-mentioned sealed pipe section. Thus, the liquid medicine flowing into the inner tube 1112 will not seep between the outer tube and the flexible tube through the gap between the upper end of the flexible tube 2 and the inner tube 1112.

[0072] It should be noted that the type and shape of the flexible tube 2 are not limited, as long as it is a telescopic structure that can be deformed under pressure at the upper end and can be restored when the pressure is released. For example, the flexible tube 2 can be made of a plastic tube or a rubber tube, etc. And the lower end of the flexible tube 2 is a hexagonal prism pipe section and the upper end is a tapered tube, or the upper end is a hexagonal pyramid pipe section and the lower end is a cylindrical tube section, etc. It also should be noted that the matching relationship between the lower end of the flexible tube 2 and the lower end of the outer tube is not limited, as long as the lower end of the flexible tube 2 can abut and support the lower end of the outer tube and the inner pipeline of the flexible tube 2 is communicated with the lower end of the inner pipeline of the outer tube. For example, the lower end of the inner tube 1112 has a boss, and the lower end of the flexible tube 2 abuts against the above-mentioned boss and is in interference fit with the inner wall of the inner tube 1112.

[0073] A switch member 3 is provided between the upper end of the outer tube and the inner tube 1112. The upper end of the switch member 3 extends outward from the upper end of the outer tube, and the lower end extends toward the lower end of the support sleeve 1 and abuts against the flexible tube 2.

[0074] It should be noted that the type of the switch member 3 and the way of the sliding fit between the switch member 3 and the support sleeve 1 are not limited. For example, in some specific embodiments, the switch member 3 is an integrally formed member, such as a plastic member or a carbon fiber member, etc., and has a connecting portion and a sliding portion. The connecting portion adopts an annular structure, the sliding portion is located around the connecting portion and extends axially. The free end of the sliding portion can deflect towards the center of the sliding portion to contract under pressure, and the free end of the sliding portion can deflect away from the center of the sliding portion to reset when the pressure is lost. The outer side walls of several sliding portions have convex structures. Correspondingly, the inner wall of the outer tube is provided with a chute extending along the length direction of the support sleeve 1, and the convex structures on several sliding portions are inserted into the corresponding chutes and slidably cooperate with them.

[0075] It should also be noted that the type of the lower end of the support sleeve 1 is not limited, as long as it can be conductively connected to an external device so as to be able to input the liquid medicine into the inner pipeline of the support sleeve 1. For example, Figure 14 as shown, the lower end of the support sleeve 1 is a connecting tapered pipe section 1215. During use, the pipeline of an external device can be inserted.

[0076] During use, when the anti-leakage joint is inserted into the locking joint, during the process of the locking joint being inserted into the inner part of the outer tube, the switch member 3 is pushed to move towards the lower end of the support sleeve 1, so as to push the upper end of the elastic tube 2 towards the lower end of the support sleeve 1, so as to connect the inner pipeline of the elastic tube 2 and the inner pipeline of the inner tube 1112 through the infusion port. Thus, the liquid medicine can flow through the inner pipeline at the lower end of the outer tube, the inner pipeline of the elastic tube 2, the infusion port, the inner pipeline of the inner tube 1112 and the liquid outlet 11121 in sequence, so as to complete the drug injection. On the contrary, after the locking joint is pulled out from the anti-leakage joint, the switch member 3 and the elastic tube 2 are subjected to external force. Thus, under the action of the self-tension of the elastic tube 2, the upper end of the elastic tube 2 moves towards the upper end of the support sleeve 1, so that the infusion port is closed, thereby effectively preventing the leakage of the liquid medicine.

[0077] Based on the above embodiments, the outer tube includes a first support tube 11 and a second support tube 12; the first support tube 11 has a first outer tube and an inner tube 1112, the inner tube 1112 is sleeved inside the head end of the first outer tube, the second support tube 12 has a second outer tube 121 and a second inner tube 122, the second inner tube 122 is sleeved inside the head end of the second outer tube 121, the tail end of the elastic tube 2 is sleeved on the head end of the second inner tube 122, and the outer peripheral surface of the tail end of the second inner tube 122 has a positive rotation thread 1214 to threadedly connect the tail end of the second support tube 12 when rotating an external device in the positive axial direction; the head end of the second outer tube 121 is inserted into the tail end of the first outer tube to form an outer tube, and among the second outer tube 121 and the first outer tube, the inner peripheral surface of the one located on the outer side has a first boss 1121 and first clamping portions 1122 arranged at intervals along its circumferential direction, and the first clamping portions 1122 are located on the side of the first boss 1121 close to the tail end of the outer tube; the outer peripheral surface of the one located on the inner side has a second clamping portion 1211 and third clamping portions 1212 arranged at intervals along its circumferential direction, the second clamping portion 1211 is close to the head end of the outer tube, and the third clamping portions 1212 are close to the tail end of the outer tube; when the second support tube 12 slides axially to the first position, the second clamping portion 1211 abuts against the first end face 11211 of the first boss 1121 close to the head end of the first outer tube; when the second support tube 12 slides axially to the second position, the second clamping portion 1211 is away from the first end face 11211 of the first boss 1121, and several third clamping portions 1212 are inserted between corresponding adjacent first clamping portions 1122, and the third clamping portions 1212 abut against the second end face 11212 of the first boss 1121 close to the tail end of the first outer tube to limit the positive rotation of the second support tube 12 around the axis and the positive sliding along the axis towards the head end of the first outer tube.

[0078] As Figure 1 shown, the first support tube 11 is a double-layer sleeve, wherein the inner tube 1112 is sleeved inside the upper end of the first outer tube, the upper end of the second support tube 12 is inserted inside the lower end of the first outer tube, the second support tube 12 is also a double-layer sleeve, wherein the second inner tube 122 is sleeved inside the second outer tube 121, the second inner tube 122 is inserted inside the first outer tube, and the upper end of the second outer tube 121 is inserted into the lower end of the first outer tube to form a complete tubular outer tube.

[0079] To limit the second support tube 12 while restricting the positive rotation of the second support tube 12 relative to the first support tube 11, refer to Figures 1 to 14In the illustrated orientation, in the pipe section where the first outer pipe and the second outer pipe 121 are inserted and fitted together, the inner circumferential surface of the outer one has a first boss 1121 and a first clamping portion 1122, and the first boss 1121 is located above the first clamping portion 1122. The outer circumferential surface of the inner one has a second clamping portion 1211 and a third clamping portion 1212, and the third clamping portion 1212 is located above the second clamping portion 1211. During the process of inserting the second support pipe 12 and the first support pipe 11 into one body, the second clamping portion 1211 is deformed under pressure to be able to pass through the pipe section where the first boss 1121 is located, and after passing through the pipe section where the first boss 1121 is located, it restores under decompression to be able to abut against or move away from the first end face 11211 of the first boss 1121 during the circumferential sliding process of the second support pipe 12. And a plurality of second clamping portions 1211 can be inserted into or withdrawn from between the corresponding adjacent third clamping portions 1212. When the second clamping portion 1211 abuts against the first boss 1121, it can limit the second support pipe 12 from withdrawing from the first support pipe 11. And when a plurality of second clamping portions 1211 are inserted between the corresponding adjacent third clamping portions 1212 and the third clamping portion 1212 abuts against the second end face 11212 of the first boss 1121, it can limit the second support pipe 12 from continuing to be inserted deeply and can limit the second support pipe 12 from sliding forward.

[0080] Correspondingly, at the lower end of the second support pipe 12, there is a right-handed thread 1214. Thus, when it is necessary to threadedly connect an external device to the lower end of this leak-proof joint, the upper end of the external device is abutted against the lower end of this leak-proof joint, and an upward axial force is applied to push the second support pipe 12 to move upward inside the first support pipe 11 to the second position. Then, the external device is rotated forward. During this process, under the cooperation of the first clamping portion 1122 and the third clamping portion 1212, the second support pipe 12 cannot rotate forward relative to the first support pipe 11. Thus, the external device can be tightened with the lower end of the second support pipe 12. After tightening, the upward axial force is removed. Under the rebounding force of the elastic pipe 2, the second support pipe 12 is pushed to move downward inside the first support pipe 11 to the first position, as Figure 1 shown. At this time, the second support pipe 12 can rotate forward or backward freely relative to the first support pipe 11 to effectively prevent this leak-proof joint from being unscrewed from above the external device.

[0081] Optionally, in some specific embodiments, as Figure 10 shown, on the inner circumferential surface of the lower end of the first outer pipe, there are a first boss 1121 and a first clamping portion 1122. The first boss 1121 is a boss structure such as an annular or arc-shaped structure extending along the circumference of the first outer pipe. Two or three or other numbers of first clamping portions 1122 are arranged at intervals along the circumference of the first outer pipe, and the first clamping portion 1122 is located below the first boss 1121. Correspondingly, as Figures 12 to 14As shown, on the outer peripheral surface of the upper end of the second outer tube 121, there are a second boss 1213, a second clamping portion 1211, and a third clamping portion 1212. The second boss 1213 is a boss structure such as an annular or arc-shaped structure extending along the circumferential direction of the second outer tube 121. Two or three or other equal numbers of the third clamping portions 1212 are arranged at intervals along the circumferential direction, and the third clamping portion 1212 is located above the second clamping portion 1211.

[0082] During assembly, the upper end of the second outer tube 121 is inserted upward into the interior of the first outer tube, so that the second clamping portion 1211 is deformed under pressure to pass through the pipe section where the first boss 1121 is located in the first outer tube, and is inserted into the interior of the pipe section of the first outer tube above the first boss 1121, and the second support tube 12 can slide axially within the first outer tube. When in use, when the second support tube 12 slides downward to the first position, as Figure 1 shown, the second clamping portion 1211 abuts against the first end face 11211 of the upper end of the first boss 1121, and the pipe section of the second outer tube 121 with the third clamping portion 1212 is located outside the first outer tube. During the process of the second support tube 12 sliding upward to the second position, the second clamping portion 1211 moves upward away from the first boss 1121, and several third clamping portions 1212 are inserted upward between the corresponding adjacent first clamping portions 1122 until the upper end of the third clamping portion 1212 abuts against the second end face 11212 of the lower end of the first boss 1121, thereby restricting the second support tube 12 from continuing to slide upward, and through the cooperation between the third clamping portion 1212 and the first clamping portion 1122, restricting the second support tube 12 from rotating forward.

[0083] Optionally, in some other specific embodiments, referring to Figures 1 to 14 the orientation shown, on the outer peripheral surface of the lower end of the first outer tube, there are a first boss 1121 and a first clamping portion 1122. The first boss 1121 is a boss structure such as an annular or arc-shaped structure extending along the circumferential direction of the first outer tube. Two or three or other equal numbers of the first clamping portions 1122 are arranged at intervals along the circumferential direction of the first outer tube, and the first clamping portion 1122 is located below the first boss 1121; correspondingly, on the inner peripheral surface of the upper end of the second outer tube 121, there are a second boss 1213, a second clamping portion 1211, and a third clamping portion 1212. The second boss 1213 is a boss structure such as an annular or arc-shaped structure extending along the circumferential direction of the second outer tube 121. Two or three or other equal numbers of the third clamping portions 1212 are arranged at intervals along the circumferential direction of the first outer tube, and the third clamping portion 1212 is located above the second clamping portion 1211.

[0084] During assembly, insert the lower end of the first outer tube downward into the interior of the second outer tube 121, causing the second clamping portion 1211 to be deformed under pressure so as to pass through the pipe section of the second outer tube 121 where the first boss 1121 is located, and insert it into the interior of the pipe section of the second outer tube 121 below the first boss 1121. Moreover, the second support tube 12 can slide axially along the outside of the first outer tube. When in use, when the second support tube 12 slides downward to the first position, the second clamping portion 1211 abuts against the first end face 11211 of the lower end of the first boss 1121, and the pipe section of the first outer tube with the third clamping portion 1212 is located outside the second outer tube 121. During the process that the second support tube 12 slides upward to the second position, the first boss 1121 moves upward away from the second clamping portion 1211, and several first clamping portions 1122 are inserted upward between the corresponding adjacent third clamping portions 1212 until the lower end of the third clamping portion 1212 abuts against the second end face 11212 of the upper end of the first boss 1121, thereby restricting the second support tube 12 from continuing to slide upward, and through the cooperation between the third clamping portion 1212 and the first clamping portion 1122, restricting the second support tube 12 from rotating forward.

[0085] It should be noted that the types of the first clamping portion 1122 and the third clamping portion 1212 are not limited, as long as they can cooperate with each other to restrict the forward rotation of the second support tube 12. For example, a rectangular structure can be adopted, or, as Figures 9 to 11 shown, a right trapezoidal structure or the like can also be adopted, and the first clamping portion 1122 and the second clamping portion 1211 can be the same or different; it should also be noted that the number and distribution mode of the first clamping portion 1122 and the third clamping portion 1212 are not limited. For example, optionally, the number of the first clamping portions 1122 is twice the number of the third clamping portions 1212. Among the first clamping portions 1122 arranged around the center line of the first outer tube, two first clamping portions 1122 are in a group, and each group of first clamping portions 1122 is arranged at intervals around the center line of the first outer tube, and the two first clamping portions 1122 in the same group are arranged in contact with each other, so that each third clamping portion 1212 can be inserted between two adjacent groups of first clamping portions 1122, or, preferably, as Figures 9 to 14 shown, the number of the first clamping portions 1122 is equal to the number of the third clamping portions 1212, and the first clamping portions 1122 are evenly arranged around the center line of the first outer tube, and the third clamping portions 1212 are evenly arranged around the center line of the second support tube 12. With such a setting, the structure of this anti-leakage joint is simple and convenient for production.

[0086] It should also be noted that the type of the second clamping portion 1211 is not limited, as long as it can pass through the first boss 1121 and be clamped and cooperated with its upper end. For example, the second clamping portion 1211 is an elastic sealing ring extending in the circumferential direction, and this elastic sealing ring is adhered to the outer peripheral surface of the corresponding first outer tube or the second outer tube 121, or, preferably, asFigures 12 to 14 As shown, the second clamping part 1211 is arranged on the outer peripheral surface of the corresponding first outer tube or the second outer tube 121 through a tensioning piece. A plurality of tensioning pieces are arranged at intervals around the central axis. The free ends of the tensioning pieces can deflect towards or away from the central axis. The second clamping part 1211 is located on the outer surface of the free ends of the tensioning pieces. When the first support tube 11 and the second support tube 12 are inserted and assembled, under the action of the contraction of the tensioning pieces when the second clamping part 1211 is pressed, the tube section with the second clamping part 1211 located on the inner side can pass through the tube section where the first boss 1121 is located. Under the action of the opening of the tensioning pieces when the second clamping part 1211 loses pressure, the second clamping part 1211 can abut against the first end face 11211 of the first boss 1121 during the sliding process of the second tube sleeve.

[0087] On the basis of the above embodiments, the head end of the second outer tube 121 is inserted into the tail end of the first outer tube. The outer peripheral surface of the second outer tube 121 has a second clamping part 1211, a third clamping part 1212 and a second boss 1213. The second boss 1213 is located on the side of the third clamping part 1212 close to the tail end of the second support tube 12. When the second support tube 12 slides axially to the second position, a plurality of third clamping parts 1212 are inserted between the corresponding adjacent first clamping parts 1122. The third clamping part 1212 abuts against the second end face 11212 of the first boss 1121, and the first clamping part 1122 abuts against the third end face 12131 of the second boss 1213 close to the head end of the second outer tube 121.

[0088] As Figures 12 to 14 shown, the outer peripheral surface of the second outer tube 121 is provided with a second clamping part 1211, a third clamping part 1212 and a second boss 1213. The second clamping part 1211, the third clamping part 1212 and the second boss 1213 are arranged from top to bottom. Thus, the second support tube 12 can be inserted into the first support tube 11. After pushing the second support tube 12 upward to the second position, the lower end of the first clamping part 1122 abuts against the third end face 12131 of the upper end of the second boss 1213, and the upper end of the third clamping part 1212 abuts against the second end face 11212 of the lower end of the first boss 1121. With such an arrangement, the manufacturing difficulty of this leak-proof joint is relatively low.

[0089] It should be noted that the types of the first boss 1121 and the second boss 1213 are not limited, as long as the above functions can be realized. For example, in some specific embodiments, both the first boss 1121 and the second boss 1213 are arc-shaped bosses extending in the circumferential direction. The two ends of a plurality of first bosses 1121 abut against the corresponding adjacent first clamping parts 1122, and the two ends of a plurality of second bosses 1213 abut against the corresponding adjacent third clamping parts 1212. Or, preferably, in some other specific embodiments, both the first boss 1121 and the second boss 1213 are annular bosses extending in the circumferential direction.

[0090] Based on the above embodiments, the tail end of the elastic tube 2 is inserted between the second outer tube 121 and the second inner tube 122. The middle tube section of the elastic tube 2 is a telescopic hose section 22. The head end of the second inner tube 122 extends into the tapered tube section 21 at the head end of the elastic tube 2, and the inner pipeline of the inner tube 1112 is a tapered hole. The tapered tube section 21 is axially slidably inserted into the inside of the inner tube 1112. The infusion port includes a first infusion port 211 and a second infusion port 212. The first infusion port 211 is located on the end wall of the tapered tube section 21, and the second infusion port 212 is located on the circumferential surface of the tapered tube section 21. When the tapered tube section 21 slides inside the inner tube 1112, the first infusion port 211 can be opened under decompression or closed under pressure, and the second infusion port 212 can be closed by being blocked by the inner tube 1112 or exposed and opened to connect or disconnect the inner pipeline of the inner tube 1112 and the inner pipeline of the elastic tube 2.

[0091] As Figure 1 shown, the lower end of the elastic tube 2 is inserted between the second outer tube 121 and the second inner tube 122 of the second support tube 12. As Figure 7 and Figure 8 shown, the upper end of the elastic tube 2 is a tapered tube section 21, and the diameter of the upper end of the tapered tube section is smaller than that of the lower end. Correspondingly, the inner pipeline of the inner tube 1112 is a tapered hole. Such a setting is beneficial to improving the smoothness of the axial movement of the second support tube 12.

[0092] Furthermore, a first infusion port 211 in the shape of a rectangle or a rhombus is opened on the end wall at the upper end of the tapered tube section 21, and / or a second infusion port 212 in the shape of a square or a circle is opened on the circumferential surface of the tapered tube section 21. During use, after the upper end of the elastic tube 2 extends upward along the inner tube 1112, the circumferential wall of the upper end of the elastic tube 2 is closely fitted with the inner tube 1112, so that the second infusion port 212 is blocked by the inner wall of the inner tube 1112 to be closed, and the end wall at the upper end of the tapered tube section 21 is deformed under the extrusion of the inner tube 1112 to close the first infusion port 211. Then, the liquid medicine cannot flow from the elastic tube 2 into the inner tube 1112. After the upper end of the elastic tube 2 retracts downward along the inner tube 1112, a gap is left between the circumferential wall of the upper end of the elastic tube 2 and the inner wall of the inner tube 1112 to open the second infusion port 212, and the end wall at the upper end of the tapered tube section 21 restores its original shape under decompression to open the first infusion port 211. Then, the liquid medicine can flow into the inner tube 1112, that is, the liquid medicine can be output through the liquid outlet 11121.

[0093] Furthermore, the middle tube section of the elastic tube 2 is a telescopic hose section 22 that can be telescoped. The telescopic hose section 22 can adopt a structure with a sawtooth-shaped or wavy-shaped longitudinal cross-section of the circumferential wall, so as to be able to expand and contract axially, and thus the elastic tube 2 has a large expansion margin.

[0094] Even further, as Figure 7As shown, reinforcing ribs 23 are provided on the telescopic hose section 22. The reinforcing ribs 23 extend circumferentially, thereby effectively enhancing the telescopic ability of the elastic tube 2.

[0095] It should be noted that the type and quantity of the reinforcing ribs 23 are not limited, as long as the above functions can be achieved. For example, the reinforcing ribs 23 can be made of elastic fiber strips or elastic nylon strips, etc. Several reinforcing ribs 23 are arranged evenly around the axis, or only one reinforcing rib 23 is provided.

[0096] On the basis of the above embodiment, the first support tube 11 includes a first connecting tube 111 and a second connecting tube 112. The first connecting tube 111 has a third outer tube 1111 and an inner tube 1112. The head end of the second connecting tube 112 is inserted into the tail end of the third outer tube 1111 to form a first outer tube. The second connecting tube 112 has a first boss 1121 and a first clamping portion 1122. Among the tail end of the third outer tube 1111 and the head end of the second connecting tube 112, the inner peripheral surface of the one located on the outer side has a positioning groove 11111, and the outer peripheral surface of the one located on the inner side has a positioning projection 1123. The positioning projection 1123 is clamped in the positioning groove 11111 to limit the relative positional relationship between the first connecting tube 111 and the second connecting tube 112.

[0097] As Figure 1 shown, the first support tube 11 is composed of a first connecting tube 111 and a second connecting tube 112 which are inserted and matched. As Figures 1 to 5 shown, the first connecting tube 111 is a double-layer sleeve. The inner tube 1112 in the first connecting tube 111 is sleeved inside the head end of the third outer tube 1111 in the first connecting tube 111, and the lower end of the third outer tube 1111 is inserted into the upper end of the second connecting tube 112 to form a first outer tube. The lower end of the second connecting tube 112 is provided with a first boss 1121 and a first clamping portion 1122 to cooperate with the second clamping portion 1211, the third clamping portion 1212 and the second boss 1213 on the second support tube 12. Then, the third outer tube 1111 of the first connecting tube 111, the second connecting tube 112, and the outer tube of the second support tube 12 are inserted into each other from top to bottom to form an outer tube.

[0098] To prevent the second connecting tube 112 from axially moving or circumferentially rotating relative to the first connecting tube 111, among the shaft sections where the upper end of the second connecting tube 112 and the lower end of the first connecting tube 111 are inserted and matched, the outer peripheral surface of the one located on the inner side has a positioning projection 1123, and the inner peripheral surface of the one located on the outer side has a positioning groove 11111, so that after the two are inserted, the relative movement between the two can be restricted through the cooperation of the positioning projection 1123 and the positioning groove 11111.

[0099] Optionally, in some specific embodiments, as Figure 4 and 5As shown, a positioning groove 11111 is formed on the inner peripheral surface at the lower end of the third outer tube 1111. Correspondingly, as Figure 9 and Figure 10 shown, a positioning protrusion 1123 is provided on the outer peripheral surface at the upper end of the second connecting tube 112. Alternatively, in some other specific embodiments, referring to Figures 1 to 14 the orientation shown, a positioning protrusion 1123 is provided on the outer peripheral surface at the lower end of the third outer tube 1111. Correspondingly, a positioning groove 11111 is formed on the inner peripheral surface at the upper end of the second connecting tube 112.

[0100] It should be noted that the number and type of the positioning protrusion 1123 and the positioning groove 11111 are not limited, as long as the first support tube 11 and the second connecting tube 112 can be restricted from relative movement. For example, in some specific embodiments, referring to Figures 1 to 14 the orientation shown, a concave stop is provided as the positioning groove 11111 on the inner peripheral surface at the lower end of the third outer tube 1111, and a convex stop is provided as the positioning protrusion 1123 on the outer peripheral surface at the upper end of the second connecting tube 112, so that the first connecting tube 111 and the second connecting tube 112 can be snap-fitted. Alternatively, preferably, in some other specific embodiments, as Figure 4 and Figure 5 shown, the inner peripheral surface at the lower end of the third outer tube 1111 has a long strip-shaped positioning groove 11111 extending axially and a circular positioning groove 11111 extending circumferentially. A plurality of long strip-shaped positioning grooves 11111 are arranged uniformly in the circumferential direction. As Figure 9 and Figure 10 shown, the outer peripheral surface at the upper end of the second connecting tube 112 has a long strip-shaped positioning protrusion 1123 extending axially and a circular positioning protrusion 1123 extending circumferentially. A plurality of long strip-shaped positioning protrusions 1123 are arranged uniformly in the circumferential direction. A plurality of long strip-shaped positioning protrusions 1123 are inserted into the corresponding long strip-shaped positioning grooves 11111, and the circular positioning protrusion 1123 is snap-fitted into the circular positioning groove 11111.

[0101] Based on the above embodiments, both the first clamping portion 1122 and the third clamping portion 1212 are right trapezoidal protrusions; when the second support tube 12 slides along the first outer tube to the second position, the first plane 11221 of the first clamping portion 1122 abuts against the third end face 12131 of the second boss 1213, and the second plane 12121 of the third clamping portion 1212 abuts against the second end face 11212 of the first boss 1121 to limit the forward sliding of the second support tube 12 along the axis towards the head end of the first outer tube; when the second support tube 12 is rotated forward, the first vertical plane 11222 of the first clamping portion 1122 can fit against the second vertical plane 12122 of the third clamping portion 1212 to limit the forward rotation of the second support tube 12 around the axis; when the second support tube 12 is rotated backward, the first inclined plane 11223 of the first clamping portion 1122 can slidably fit against the second inclined plane 12123 of the third clamping portion 1212 to guide the reverse sliding of the second support tube 12 along the axis towards the tail end of the first outer tube so as to withdraw from the first outer tube.

[0102] Optionally, in some specific embodiments, the second support tube 12 has a third clamping portion 1212, and the first support tube 11 has a first clamping portion 1122. As Figure 10 and Figure 11 shown, the first clamping portion 1122 is a right trapezoidal protrusion. As Figure 12 and Figure 14 shown, the third clamping portion 1212 is a right trapezoidal protrusion. After the upper end of the second support tube 12 is inserted into the first support tube 11 along the circumferential direction to the second position, the first plane 11221 of the first clamping portion 1122 is parallel to the second plane 12121 of the third clamping portion 1212. The first vertical plane 11222 of the same first clamping portion 1122 is opposite to the second vertical plane 12122 of an adjacent second clamping portion 1211 of its own, and the first inclined plane 11223 is opposite to the second inclined plane 12123 of another adjacent second clamping portion 1211 of its own. With such a setting, when the second support tube 12 is rotated forward, the first vertical plane 11222 of the first clamping portion 1122 abuts against and fits against the second vertical plane 12122 of the second clamping portion 1211 adjacent to its own. When the second support tube 12 is rotated backward, the first inclined plane 11223 of the first clamping portion 1122 abuts against and fits against the second inclined plane 12123 of the second clamping portion 1211 adjacent to its own. Thus, during the process of rotating the second support tube 12 backward, the third clamping portion 1212 of the second support tube 12 slides along the first inclined plane 11223 of the first clamping portion 1122 of the first support tube 11, so that the second support tube 12 can withdraw from the first support tube 11 under the guidance of the first clamping portion 1122, so as to further effectively prevent the leak-proof joint from being unscrewed from the external device.

[0103] Optionally, in some other specific embodiments, the second support tube 12 has a first clamping portion 1122 formed by a right trapezoidal protrusion, and the first support tube 11 has a third clamping portion 1212 formed by a right trapezoidal protrusion. The principle is the same as that of the embodiment where the second support tube 12 has a third clamping portion 1212 formed by a right trapezoidal protrusion and the first support tube 11 has a first clamping portion 1122 formed by a right trapezoidal protrusion, so it will not be elaborated here too much.

[0104] Based on the above embodiments, the inner wall of the head end of the outer tube has an internal thread 11112 to be threadedly engaged with the inner locking joint; and the head end of the switch member 3 extends to the tube section of the outer tube having the internal thread 11112.

[0105] As Figures 1 to 3 , Figure 5 shown, an internal thread 11112 is machined on the inner circumferential surface of the upper end of the outer tube, so that an inner locking joint with an external thread machined on its outer circumferential surface can be threadedly connected. Correspondingly, the upper end of the switch member 3 extends to the tube section where the internal thread 11112 is located. Thus, during the process of inserting the inner locking joint into the interior of the outer tube and tightening it with the anti-leakage joint, the switch member 3 will be simultaneously pushed to move downward along the axis, so as to push the upper end of the elastic tube 2 to retract downward in the inner tube 1112, thereby opening the infusion port, such that the liquid medicine can flow out successively through the lower end of the inner tube 1112 section of the outer tube, the inner tube 1112 section of the elastic tube 2, the infusion port and the liquid outlet 11121. Then, the anti-leakage joint effectively prevents the leakage of the liquid medicine when it is not in use.

[0106] It should be noted that there is no limitation on whether the upper end of the switch member 3 extends out of the outer tube, as long as the compression amount requirement of the elastic tube 2 can be satisfied to achieve the above function of opening the infusion port. For example, optionally, the upper end of the switch member 3 is retracted inside the outer tube, or the upper end of the switch member 3 protrudes to the outside of the outer tube.

[0107] Based on the above embodiments, the switch member 3 has a positioning ring 31 and at least two guiding portions 32. A plurality of guiding portions 32 are installed on the same side of the positioning ring 31, and the guiding portions 32 extend axially; the positioning ring 31 is sleeved and clamped on the elastic tube 2; the connecting frame between the inner tube 1112 and the outer tube has insertion through holes 1113, and a plurality of insertion through holes 1113 are arranged around the axis. A plurality of guiding portions 32 are slidably inserted into the corresponding insertion through holes 1113, and the free ends of the guiding portions 32 extend to one side of the head end of the outer tube.

[0108] As Figure 6As shown, the bottom of the switch member 3 is a positioning ring 31, which is sleeved outside the elastic tube 2. It should be noted that the clamping method between the positioning ring 31 and the elastic tube 2 is not limited. For example, a circumferential annular groove 214 is provided on the outer peripheral surface of the elastic tube 2 to be clamped and matched with the positioning ring 31, or the elastic tube 2 and the positioning ring 31 are in interference fit, etc.

[0109] As Figure 1 and Figure 4 shown, the connecting frame for connecting the outer tube and the inner tube 1112 has an axially penetrating insertion through-hole 1113. Correspondingly, a plurality of guiding portions 32 are fixedly connected above the positioning ring 31 and extend axially to be inserted into the corresponding insertion through-holes 1113, so that the switch member 3 can be guided to move axially through the insertion through-holes 1113, and the position of the switch member 3 is restricted by the above connection structure, so that it cannot exit from above the outer tube. Such a setting is beneficial to ensuring the anti-liquid leakage performance of the anti-leakage joint.

[0110] It should be noted that the types of the guiding portions 32 and the insertion through-holes 1113 are not limited, as long as the above functions can be achieved. For example, in some specific embodiments, the guiding portion 32 can be a cylindrical rod, and correspondingly, the insertion through-hole 1113 can be a round hole, so that the guiding portion 32 can be inserted into the insertion through-hole 1113 and have a clearance fit with it. Or, preferably, in some other specific embodiments, as Figure 6 shown, the guiding portion 32 can be an arched sheet body, and correspondingly, as Figure 4 shown, the insertion through-hole 1113 can be an arc-shaped hole extending along the circumference of the anti-leakage joint, so that the guiding portion 32 can be inserted into the insertion through-hole 1113 and have a clearance fit with it.

[0111] Preferably, as Figures 1 to 14 shown, the upper ends of the second inner tube 122 and the second support tube 12 are both plug-in conical tube sections with the same shape such as a conical tube section or a hexagonal pyramid tube section. Thus, the upper conical tube section 21 of the elastic tube 2, the upper end of the second inner tube 122, and the upper end of the second support tube 12 are sequentially sleeved from inside to outside, which is beneficial to improving the smoothness of the upward extension or downward retraction of the upper end of the elastic tube 2.

[0112] On the basis of the above embodiments, a protective cap is further included. The head end of the support sleeve 1 can be inserted into or pulled out of the inside of the protective cap. Usually, in the anti-leakage joint, the upper end of the support sleeve 1 is inserted into the inside of the protective cap, so that the upper end opening of the support sleeve 1 can be sealed by the protective cap to protect the structure sleeved inside the support sleeve 1. When the anti-leakage joint needs to be used, the anti-leakage joint can be pulled out of the protective cap.

[0113] In addition to the above-mentioned automatic closing and leak-proof joint, the present invention also provides a syringe including the automatic closing and leak-proof joint disclosed in the above embodiments. For the structures of other parts of the syringe, reference may be made to the prior art and will not be elaborated herein.

[0114] It should be noted that the relational terms such as "first" and "second" mentioned above are only used to distinguish one entity from several other entities, and do not necessarily require or imply any such actual relationship or order between these entities; the "upper surface, lower surface, top, bottom" and the orientation terms "up, down, left, right" mentioned above are all defined based on the accompanying drawings of the specification.

[0115] In this specification, the various embodiments are described in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts among the various embodiments can be referred to each other.

[0116] The above has introduced in detail the automatic closing and leak-proof joint and syringe provided by the present invention. Specific examples are used herein to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the present invention.

Claims

1. An automatic closed leak-proof joint, characterized in that: include: A support sleeve (1) comprising an outer tube and an inner tube (1112), wherein the inner tube (1112) is sleeved inside the head end of the outer tube, the aperture of the head end of the inner tube (1112) is smaller than the aperture of the tail end of the inner tube (1112), and the end wall of the head end of the inner tube (1112) has a liquid outlet (11121); The elastic tube (2) is a telescopic structure and is sleeved inside the outer tube. The rear end of the elastic tube (2) is supported by the rear end of the outer tube, and the inner pipe of the elastic tube (2) is connected to the rear end of the inner pipe of the outer tube. The head end of the elastic tube (2) has an infusion port. The head end of the elastic tube (2) can be axially slidable and sealed and inserted into the interior of the inner tube (1112) to open or close the infusion port. The switch member (3) is axially slidably disposed between the inner tube (1112) and the outer tube, the rear end of the switch member (3) abuts against the elastic tube (2), and when the head end of the support sleeve (1) is plugged into a locking joint, the locking joint can push the switch member (3) to move toward the rear end of the support sleeve (1), thereby pushing the elastic tube (2) to slide axially.

2. The automatic sealing and leak-proof joint according to claim 1, characterized in that: The outer tube comprises a first supporting tube (11) and a second supporting tube (12); The first support tube (11) comprises a first outer tube and the inner tube (1112), the inner tube (1112) being sleeved inside the head end of the first outer tube; the second support tube (12) comprises a second outer tube (121) and a second inner tube (122), the second inner tube (122) being sleeved inside the head end of the second outer tube (121); the tail end of the elastic tube (2) being sleeved inside the head end of the second inner tube (122), the outer peripheral surface of the tail end of the second inner tube (122) comprising a positive thread (1214) so ​​as to be threadedly connected to the tail end of the second support tube (12) when the external device is rotated in the positive direction around the axial direction; The head end of the second outer tube (121) is plugged into the tail end of the first outer tube to form the outer tube, and the inner circumferential surface of the one located on the outside of the second outer tube (121) and the first outer tube has a first boss (1121) and first clamping portions (1122) arranged at intervals along its own circumferential direction, and the first clamping portion (1122) is located on a side of the first boss (1121) close to the tail end of the outer tube; the outer circumferential surface of the one located on the inside has a second clamping portion (1211) and third clamping portions (1212) arranged at intervals along its own circumferential direction, the second clamping portion (1211) is close to the head end of the outer tube, and the third clamping portion (1212) is close to the tail end of the outer tube; When the second support tube (12) slides axially to a first position, the second clamping portion (1211) abuts against a first end surface (11211) of the first boss (1121) close to the first outer tube head end; When the second support tube (12) slides axially to the second position, the second clamping portion (1211) is away from the first end surface (11211) of the first boss (1121), a plurality of the third clamping portions (1212) are inserted between corresponding adjacent first clamping portions (1122), and the third clamping portions (1212) abut against the second end surface (11212) of the first boss (1121) close to the tail end of the first outer tube, so as to limit the positive rotation of the second support tube (12) around the axis and the positive sliding along the axial direction toward the head end of the first outer tube.

3. The automatic sealing and leak-proof joint according to claim 2, characterized in that: The head end of the second outer tube (121) is inserted into the rear end of the first outer tube, and the outer circumferential surface of the second outer tube (121) comprises the second clamping portion (1211), the third clamping portion (1212) and the second boss (1213), and the second boss (1213) is located on a side of the third clamping portion (1212) close to the rear end of the second support tube (12); When the second support tube (12) slides axially to the second position, a plurality of the third clamping portions (1212) are inserted between corresponding adjacent first clamping portions (1122), and the third clamping portions (1212) abut against the second end surface (11212) of the first boss (1121), and the first clamping portion (1122) abuts against the third end surface (12131) of the second boss (1213) close to the head end of the second outer tube (121).

4. The automatic sealing and leak-proof joint according to claim 3, characterized in that: The first boss (1121) is an annular boss extending along the circumference of the first outer tube, and the second boss (1213) is an annular boss extending along the circumference of the second outer tube (121).

5. The automatic sealing and leak-proof joint according to claim 3, characterized in that: The rear end of the elastic tube (2) is inserted between the second outer tube (121) and the second inner tube (122); the middle tube section of the elastic tube (2) is a telescopic hose section (22); the head end of the second inner tube (122) extends into the conical tube section (21) at the head end of the elastic tube (2); the inner tube of the inner tube (1112) is a conical channel; the conical tube section (21) is inserted into the interior of the inner tube (1112) slidably along the axial direction; The infusion port comprises a first infusion port (211) and a second infusion port (212); the first infusion port (211) is located on the end wall of the conical tube section (21), and the second infusion port (212) is located on the circumferential surface of the conical tube section (21); and when the conical tube section (21) slides inside the inner tube (1112), the first infusion port (211) can be opened by loss of pressure or closed by pressure, and the second infusion port (212) can be closed by being blocked by the inner tube (1112) or opened by being exposed, so as to connect or disconnect the inner pipeline of the inner tube (1112) and the inner pipeline of the elastic tube (2).

6. The automatic sealing and leak-proof joint according to claim 3, characterized in that: The first supporting tube (11) comprises a first connecting tube (111) and a second connecting tube (112); the first connecting tube (111) comprises a third outer tube (1111) and the inner tube (1112); the head end of the second connecting tube (112) is plugged into the tail end of the third outer tube (1111) to form the first outer tube; the second connecting tube (112) comprises the first boss (1121) and the first clamping portion (1122); The tail end of the third outer tube (1111) and the head end of the second connecting tube (112) have a positioning groove (11111) on the inner circumference of the outer one and a positioning protrusion (1123) on the outer circumference of the inner one, and the positioning protrusion (1123) is engaged in the positioning groove (11111) to limit the relative position relationship between the first connecting tube (111) and the second connecting tube (112).

7. The automatic sealing and leak-proof joint according to claim 3, characterized in that: The first clamping portion (1122) and the third clamping portion (1212) are both right-angled trapezoidal protrusions; When the second support tube (12) slides along the first outer tube to a second position, the first plane (11221) of the first clamping portion (1122) abuts against the third end surface (12131) of the second boss (1213), and the second plane (12121) of the third clamping portion (1212) abuts against the second end surface (11212) of the first boss (1121), so as to limit the positive sliding of the second support tube (12) along the axial direction toward the head end of the first outer tube; When the second support tube (12) is rotated in the forward direction, the first vertical surface (11222) of the first clamping portion (1122) can be attached to the second vertical surface (12122) of the third clamping portion (1212), so as to limit the forward rotation of the second support tube (12) around the axis; When the second support tube (12) is rotated in the reverse direction, the first inclined surface (11223) of the first clamping portion (1122) can be slidably attached to the second inclined surface (12123) of the third clamping portion (1212), so as to guide the second support tube (12) to slide in the reverse direction along the axial direction toward the rear end of the first outer tube so as to withdraw from the first outer tube.

8. The automatic sealing and leak-proof joint according to claim 1, characterized in that: The inner wall of the head end of the outer tube has an internal thread (11112) to cooperate with the thread of the inner locking joint; Furthermore, the head end of the switch member (3) extends to the pipe section of the outer pipe having the internal thread (11112).

9. The automatic sealing and leak-proof joint according to claim 1, characterized in that: The switch element (3) comprises a positioning ring (31) and at least two guide portions (32), a plurality of the guide portions (32) are mounted on the same side of the positioning ring (31), and the guide portions (32) extend in the axial direction; The positioning ring (31) is sleeved on and clamped on the elastic tube (2); The connection frame between the inner tube (1112) and the outer tube has a plug-in through hole (1113), a plurality of the plug-in through holes (1113) are arranged around an axis, a plurality of the guide portions (32) are slidably plugged into corresponding plug-in through holes (1113), and a free end of the guide portion (32) extends to one side of the head end of the outer tube.

10. A syringe, characterized in that: The invention comprises the automatic sealing and leak-proof joint as described in any one of claims 1 to 9.

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