Remaining needle

Abstract

The utility model discloses an indwelling needle which comprises a catheter seat, a catheter installed at the front end of the catheter seat, an isolation plug installed in the catheter seat, a protective cylinder with a guide hole extending in the axial direction and a limiting hole extending in the circumferential direction from the front end of the guide hole, and a needle seat arranged in the protective cylinder, wherein the front end of the needle seat extends out of the protective cylinder and is connected to the rear end of the catheter seat in an inserted mode. The rear end of the puncture needle is connected with the needle base, the front end of the puncture needle sequentially penetrates through the isolation plug and the catheter, the needle holding handle penetrates through the limiting hole and is connected with the needle base, and the reset spring is arranged on the needle base in a sleeving mode and elastically abuts against the position between the front end of the protective cylinder and the rear end of the needle base. The puncture needle can be pulled out without manual traction, the risks of instability and misoperation caused by manual needle pulling can be eliminated, and the puncture needle pulling device is safer, more reliable, more convenient and quicker.

Description

Technical Field

[0001] The utility model relates to the technical field of medical devices, in particular to an indwelling needle. Background Art

[0002] An intravenous catheter, also known as an intravenous cannula, consists of a flexible catheter / cannula that can be placed within the blood vessel and a stainless steel puncture needle. During use, the catheter and puncture needle are inserted into the blood vessel together. Once the catheter is fully inserted, the puncture needle is withdrawn, leaving only the flexible catheter in the blood vessel for infusion therapy.

[0003] Conventional indwelling catheters mainly rely on nursing staff to manually remove the puncture needle. There are two main problems with manual removal of the puncture needle: first, physiological shaking of the hand may cause instability in the needle removal process, thereby aggravating the patient's pain to a certain extent; second, manual needle removal increases the possibility of operational errors, thereby increasing the risk of puncture infection. Utility Model Content

[0004] The purpose of the utility model is to provide an indwelling needle capable of automatically pulling out a puncture needle.

[0005] In order to achieve the above-mentioned purpose, the technical solution proposed by the present utility model is:

[0006] A retention needle comprises a catheter seat, a catheter, an isolation plug, a protective tube, a needle seat, a puncture needle, a needle holding handle and a reset spring. The catheter is installed at the front end of the catheter seat, the isolation plug is installed in the catheter seat, an axially extending guide hole and a limiting hole extending circumferentially from the front end of the guide hole are opened on the wall of the protective tube, the needle seat is arranged in the protective tube, the front end of the needle seat extends out of the protective tube and is plugged into the rear end of the catheter seat, the needle seat can move axially and rotate circumferentially relative to the protective tube, the rear end of the puncture needle is connected to the needle seat, and its front end passes through the isolation plug and the catheter in turn, the needle holding handle passes through the limiting hole and is connected to the needle seat, the reset spring is sleeved on the needle seat and elastically pressed between the front end of the protective tube and the rear end of the needle seat, so that after the needle holding handle slides from the limiting hole into the guide hole, the needle seat is driven to move backward to pull out the puncture needle.

[0007] Preferably, the protective tube includes an outer tube and an inner tube, the inner tube is slidably inserted in the outer tube, the rear end of the inner tube extends out of the outer tube, the outer tube and the inner tube are both provided with the guide hole and the limiting hole, and the guide hole of the outer tube extends backward to pass through the outer tube so that the needle holding handle can pass through the outer tube along the guide hole, the needle seat is slidably inserted in the inner tube and its front end extends out of the outer tube, and the reset spring elastically presses between the front end of the outer tube and the rear end of the needle seat.

[0008] Preferably, the inner cylinder comprises an inner cylinder body having a hollow interior and an open front end, and a front outer flange ring circumferentially protruding outward from the front end of the inner cylinder body; the outer cylinder comprises an outer cylinder body having a hollow interior and open ends, a front inner flange ring circumferentially protruding inward from the front end of the outer cylinder body, and a rear inner flange ring circumferentially protruding inward from the rear end of the outer cylinder body; the inner diameter of the front inner flange ring is smaller than the inner diameter of the inner cylinder body and is greater than or equal to the outer diameter of the needle hub; the inner diameter of the rear inner flange ring is smaller than the outer diameter of the front outer flange ring and is greater than or equal to the outer diameter of the inner cylinder body. The rear end of the needle hub has a rear outer flange ring circumferentially protruding outward, and the return spring elastically presses between the front inner flange ring and the rear outer flange ring.

[0009] Preferably, one of the front end outer wall of the needle hub and the rear end inner wall of the catheter hub is provided with a plurality of circumferentially arranged and axially extending ridges, and the other is correspondingly provided with a plurality of slots for inserting the ridges.

[0010] Preferably, it also includes a needle protection cap sleeved outside the catheter.

[0011] Preferably, the needle seat and the catheter seat are interference fit.

[0012] Preferably, the catheter seat has an infusion end located between the catheter and the isolation plug, and the catheter seat is further provided with a one-way valve located between the catheter and the infusion end for allowing liquid to flow unidirectionally from the infusion end to the catheter.

[0013] Preferably, the one-way valve comprises at least two leaflets with closable edges, one end of each leaflet being fixedly connected to the catheter adapter and the other end extending toward the catheter. When liquid flows from the infusion end toward the catheter, the leaflets separate. When liquid flows from the catheter toward the infusion end, the leaflets remain closed.

[0014] By adopting the above technical solution, the beneficial effects of the utility model are as follows: the utility model controls the movement and limitation of the needle seat by opening a limiting hole and a guide hole on the protective tube that cooperate with the needle holding handle, and arranges a reset spring between the front end of the protective tube and the rear end of the needle seat, so that after the needle holding handle slides from the limiting hole into the guide hole, it can drive the needle seat to move backward to automatically pull out the puncture needle. There is no need to manually pull out the puncture needle, which can eliminate the instability and risk of operational errors in manual needle removal, and is safer, more reliable, convenient and quick. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematic diagram of the three-dimensional structure of the puncture state of this embodiment.

[0016] Figure 2 for Figure 1 Isometric cutaway diagram of .

[0017] Figure 3It is a schematic diagram of the three-dimensional structure of the needle-pulling state of this embodiment.

[0018] Figure 4 for Figure 3 Isometric cutaway diagram of .

[0019] Figure 5 for Figure 3 Schematic cross-sectional view of .

[0020] Among them: 1. Catheter seat; 11. Infusion end; 12. Slot; 2. Catheter; 3. Isolation plug; 4. Casing; 41. Guide hole; 42. Limit hole; 43. Outer tube; 431. Outer tube body; 432. Front inner flange ring; 433. Rear inner flange ring; 44. Inner tube; 441. Inner tube body; 442. Front outer flange ring; 5. Needle seat; 51. Rear outer flange ring; 52. Ridge; 6. Puncture needle; 7. Needle handle; 8. Return spring; 9. One-way valve; 91. Leaflet. DETAILED DESCRIPTION

[0021] The present invention will be further described below with reference to the accompanying drawings and specific implementation methods.

[0022] like Figures 1 to 5 As shown, the indwelling needle of this embodiment includes a catheter seat 1, a catheter 2, an isolation plug 3, a protective tube 4, a needle seat 5, a puncture needle 6, a needle holding handle 7, a reset spring 8 and a needle guard cap. Among them, the catheter 2 is installed at the front end of the catheter seat 1, the needle guard cap is arranged outside the catheter 2, the isolation plug 3 is installed in the catheter seat 1, and the infusion end 11 of the catheter seat 1 is located between the catheter 2 and the isolation plug 3. The wall of the protective tube 4 is provided with an axially extending guide hole 41 and a limiting hole 42 extending circumferentially from the front end of the guide hole 41. The needle seat 5 is arranged in the protective tube 4, and the front end of the needle seat 5 extends out of the protective tube 4 and is plugged into the rear end of the catheter seat 1. The needle seat 5 can slide axially and rotate circumferentially relative to the protective tube 4. The rear end of the puncture needle 6 is connected to the needle seat 5, and the front end of the puncture needle 6 passes through the isolation plug 3 and the catheter 2 in turn. The needle holding handle 7 is connected to the needle seat 5 through the limiting hole 42. The return spring 8 is sleeved on the needle seat 5 and elastically presses between the front end of the protective tube 4 and the rear end of the needle seat 5, so as to drive the needle seat 5 to move backward to pull out the puncture needle 6 after the needle holding handle 7 slides from the limiting hole 42 into the guide hole 41.

[0023] This embodiment utilizes a return spring 8 to automatically drive the needle holder 5 to move backward along the protective sleeve 4, eliminating the need for manual pulling of the puncture needle 6. This eliminates the instability and risk of manual needle removal, making it safer, more reliable, more convenient, and faster. After the puncture needle 6 is fully retracted into the protective sleeve 4, the protective sleeve 4 can provide a certain degree of protection, preventing the puncture needle 6 from injuring medical personnel.

[0024] The needle hub 5 of this embodiment can be inserted into the rear end of the catheter hub 1 by interference fit or snap fit, so that the needle hub 5 can be directly pulled out of the catheter hub 1 under the action of the return spring 8.

[0025] In this embodiment, the front end outer wall of the needle hub 5 is provided with a plurality of circumferentially arranged, axially extending ridges 52. The rear end inner wall of the catheter hub 1 is correspondingly provided with a plurality of slots 12 for receiving the ridges 52. The ridges 52 and slots 12 restrict circumferential rotation of the needle hub 5 relative to the catheter hub 1. This eliminates the risk of the needle hub 5 rotating and causing the puncture needle 6 to puncture a blood vessel when the protective sleeve 4 is rotated to slide the needle handle 7 from the retaining hole 42 into the guide hole 41, further improving the safety of the indwelling needle.

[0026] The protective sleeve 4 of this embodiment comprises an outer sleeve 43 and an inner sleeve 44 that is slidably inserted within the outer sleeve 43, with its rear end extending outward from the outer sleeve 43. Both the outer sleeve 43 and the inner sleeve 44 are provided with a guide hole 41 and a stop hole 42, with the guide hole 41 of the outer sleeve 43 extending rearward through the outer sleeve 43. The needle holder 5 is slidably inserted within the inner sleeve 44, with its front end extending outward from the outer sleeve 43. The needle handle 7 passes through the guide holes 41 of the outer sleeve 43 and the inner sleeve 44, respectively, and is connected to the rear end of the needle holder 5. A return spring 8 is elastically pressed between the front end of the outer sleeve 43 and the rear end of the needle holder 5.

[0027] The protective tube 4 of this embodiment adopts a folding design. The inner tube 44 can be retracted into and extended from the outer tube 43, so that when the puncture needle 6 is inserted into the catheter 2, the overall volume of the protective tube 4 becomes smaller, which is conducive to the miniaturization of the indwelling needle.

[0028] Specifically, the inner cylinder 44 of this embodiment includes an inner cylinder body 441 having a hollow interior and an open front end, and a front outer flange ring 442 circumferentially extending outward from the front end of the inner cylinder body 441. The outer cylinder 43 of this embodiment includes an outer cylinder body 431 having a hollow interior and open ends, a front inner flange ring 432 circumferentially extending inward from the front end of the outer cylinder body 431, and a rear inner flange ring 433 circumferentially extending inward from the rear end of the outer cylinder body 431. The rear end of the needle hub 5 of this embodiment has a rear outer flange ring 51 circumferentially extending outward.

[0029] The inner diameter a of the front inner flange ring 432 is smaller than the inner diameter φ1 of the inner cylinder 441 and serves to position the inner cylinder 44 and the return spring 8. To allow the needle hub 5 to retract into the protective sleeve 4, the inner diameter a of the front inner flange ring 432 must be larger than the outer diameter φ2 of the needle hub. This is because the front end of the needle hub 5 is provided with a ridge 52. If the needle hub 5 does not have the ridge 52, the inner diameter a of the front inner flange ring 432 can be equal to the outer diameter φ2 of the needle hub. The inner diameter b of the rear inner flange ring 433 is smaller than the outer diameter c of the front outer flange ring 442 and is greater than or equal to the outer diameter φ3 of the inner cylinder 441, thereby preventing the inner cylinder 44 from separating from the outer cylinder 43.

[0030] In this embodiment, the rear end of the inner cylinder 44 is inserted into the rear inner flange ring 433 , the front end of the needle seat 5 is inserted into the front inner flange ring 432 , and the return spring 8 elastically presses between the front inner flange ring 432 and the rear outer flange ring 51 .

[0031] In order to prevent blood backflow, a one-way valve 9 is provided in the catheter adapter 1 in this embodiment. The one-way valve 9 is located between the catheter 2 and the infusion end 11 and is used to allow liquid to flow in one direction from the infusion end 11 to the catheter 2 .

[0032] Specifically, the one-way valve 9 includes at least two leaflets 91 with edges that can be closed. One end of the leaflet 91 is fixedly connected to the catheter seat 1, and the other end extends toward the catheter 2. When the liquid flows from the infusion end 11 toward the catheter 2, the leaflet 91 separates. When the liquid flows from the catheter 2 toward the infusion end 11, the leaflet 91 remains closed.

[0033] The working principle of this embodiment is as follows: in the initial state, the puncture needle 6 is inserted into the catheter 2, the needle holding handle 7 is limited in the limiting hole 42, the return spring 8 is compressed, and the inner tube 44 is retracted into the outer tube 43. When the puncture needle 6 needs to be removed, one hand holds the catheter holder 1, and the other hand rotates the protective tube 4, so that the needle holding handle 7 slides from the limiting hole 42 into the guide hole 41. The return spring 8 drives the needle holder 5 and the inner tube 44 to move backward together until the front outer flange ring 442 of the inner tube 44 abuts the rear inner flange ring 433 of the outer tube 43, driving the needle holder 5 in the inner tube 44 to move backward to the rear end of the inner tube 44, thus completely retracting the puncture needle 6 into the protective tube 4.

[0034] Although the present invention has been specifically shown and described in conjunction with the preferred embodiments, it should be understood by those skilled in the art that various changes in form and details of the present invention are within the scope of protection of the present invention without departing from the spirit and scope of the present invention as defined in the appended claims.

Claims

1. An indwelling needle, characterized in that: include: Catheter hub (1); A catheter (2) is mounted on the front end of the catheter seat (1); An isolation plug (3) is installed in the catheter seat (1); The protective tube (4) has a guide hole (41) extending axially and a limiting hole (42) extending circumferentially from the front end of the guide hole (41) on its wall; The needle seat (5) is arranged in the protective tube (4), the front end of the needle seat (5) extends out of the protective tube (4) and is plugged into the rear end of the catheter seat (1), and the needle seat (5) can move axially and rotate circumferentially relative to the protective tube (4); A puncture needle (6), the rear end of which is connected to the needle seat (5), and the front end of which passes through the isolation plug (3) and the catheter (2) in sequence; The needle handle (7) passes through the limiting hole (42) and is connected to the needle seat (5); A reset spring (8) is sleeved on the needle seat (5) and elastically presses between the front end of the protective tube (4) and the rear end of the needle seat (5) so as to drive the needle seat (5) to move backward to pull out the puncture needle (6) after the needle holding handle (7) slides from the limiting hole (42) into the guide hole (41).

2. The indwelling needle according to claim 1, characterized in that The protective tube (4) comprises an outer tube (43) and an inner tube (44); the inner tube (44) is slidably inserted into the outer tube (43), and the rear end of the inner tube (44) extends out of the outer tube (43); the outer tube (43) and the inner tube (44) are both provided with the guide hole (41) and the limiting hole (42), and the guide hole (41) of the outer tube (43) extends backward to penetrate the outer tube (43), so that the needle holding handle (7) can pass through the outer tube (43) along the guide hole (41); The needle seat (5) is slidably inserted into the inner tube (44) and its front end extends out of the outer tube (43), and the return spring (8) elastically presses between the front end of the outer tube (43) and the rear end of the needle seat (5).

3. The indwelling needle according to claim 2, characterized in that The inner cylinder (44) comprises: an inner cylinder body (441) which is hollow inside and open at the front end, and a front outer flange ring (442) which protrudes outward from the front end of the inner cylinder body (441); The outer cylinder (43) comprises: an outer cylinder body (431) which is hollow inside and open at both ends, a front inner flange ring (432) which protrudes inwardly from the front end of the outer cylinder body (431), and a rear inner flange ring (433) which protrudes inwardly from the rear end of the outer cylinder body (431), wherein the inner diameter of the front inner flange ring (432) is smaller than the inner diameter of the inner cylinder body (441) and is greater than or equal to the outer diameter of the needle seat (5), and the inner diameter of the rear inner flange ring (433) is smaller than the outer diameter of the front outer flange ring (442) and is greater than or equal to the outer diameter of the inner cylinder body (441); The rear end of the needle seat (5) has a rear outer flange ring (51) that protrudes outward in the circumferential direction, and the return spring (8) elastically presses between the front inner flange ring (432) and the rear outer flange ring (51).

4. The indwelling needle according to claim 1, characterized in that One of the front end outer wall of the needle seat (5) and the rear end inner wall of the catheter seat (1) is provided with a plurality of circumferentially arranged and axially extending ridges (52), and the other is correspondingly provided with a plurality of slots (12) for the ridges (52) to be inserted.

5. The indwelling needle according to claim 1, characterized in that It also includes a needle protection cap which is sleeved on the outside of the catheter (2).

6. The indwelling needle according to claim 1, characterized in that The needle seat (5) and the catheter seat (1) are interference fit.

7. The indwelling needle according to any one of claims 1 to 6, characterized in that: The catheter seat (1) has an infusion end (11) located between the catheter (2) and the isolation plug (3). The catheter seat (1) is also provided with a one-way valve (9) located between the catheter (2) and the infusion end (11) for allowing liquid to flow in one direction from the infusion end (11) to the catheter (2).

8. The indwelling needle according to claim 7, characterized in that The one-way valve (9) comprises at least two leaflets (91) whose edges can be closed together. One end of the leaflet (91) is fixedly connected to the catheter seat (1), and the other end extends toward the catheter (2). When the liquid flows from the infusion end (11) toward the catheter (2), the leaflets (91) separate; when the liquid flows from the catheter (2) toward the infusion end (11), the leaflets (91) remain closed.

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