Backflow prevention negative pressure drainage device

Abstract

The utility model provides an anti-backflow negative pressure drainage device, which belongs to the technical field of medical drainage devices and is characterized in that one end of a negative pressure cylinder is provided with a plurality of outlets, each outlet is detachably connected with a transition tube, and the other end of each transition tube is detachably connected with a drainage tube; the piston rod is formed by sequentially pivoting a plurality of joints, a threaded through hole is formed in the other end of the negative pressure cylinder, and each joint is provided with an external thread matched with an internal thread on the threaded through hole; containing grooves used for containing joints are formed in the positions, on the two sides of the threaded through hole, of the negative pressure cylinder. The arc-shaped protrusion in the screw groove of the piston rod is matched with the arc-shaped protrusion in the threaded through hole, inversion of the piston rod is prevented, and a negative pressure environment can be continuously and stably generated; drainage can be performed on multiple tissues at the same time, so that the use efficiency is improved, and the operation steps of medical personnel are reduced; and the piston rod can be folded and accommodated in the accommodating groove, so that the piston rod is prevented from being touched, and the use safety is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of medical drains, in particular to an anti-backflow negative pressure drain. Background Art

[0002] The statements in this section merely provide background technology related to the present invention and do not necessarily constitute prior art.

[0003] During medical surgery, it is necessary to drain tissue effusion to prevent infection. The common method of existing traditional negative pressure drainage is to connect a drainage tube or an indwelling needle to a negative pressure generator for drainage. This drainage method requires the drainage tube or indwelling needle to be buried in the tissue, and then an external negative pressure generator is used to generate negative pressure to suck out the tissue fluid for drainage. In actual drainage operations in hospitals, operators use syringes as negative pressure generators. The syringes need to be kept in a negative pressure position for a long time to provide a stable negative pressure environment. The Chinese utility model patent with announcement number CN216169126U discloses a medical drainage device for negative pressure drainage of subcutaneous fluid, which achieves the positioning of the negative pressure position by arranging threads on the piston and the negative pressure cylinder through thread matching. However, when using the drainage device, the piston needs to be pulled to the threaded position to cooperate with the thread on the negative pressure cylinder. The negative pressure regulation is not accurate, the piston is easy to rotate under the action of negative pressure, and the piston rod is easy to be touched by the patient or medical staff, resulting in negative pressure failure. In addition, the drainage device can only drain one place and cannot drain multiple surgical sites at the same time. Utility Model Content

[0004] The purpose of the utility model is to provide a negative pressure drainer for preventing backflow, so as to solve at least one technical problem existing in the above-mentioned background technology.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] The utility model provides an anti-backflow negative pressure drainer, comprising a negative pressure cylinder, a piston rod rotatably provided in the negative pressure cylinder, the end of the piston rod rotatably connected to a piston plate, one end of the negative pressure cylinder is provided with a plurality of outflow ports, each of the outflow ports is detachably connected to a transition pipe, and the other end of the transition pipe is detachably connected to a drainage pipe; the piston rod is composed of a plurality of joints pivotally connected in sequence, the other end of the negative pressure cylinder is provided with a threaded through hole, each of the joints is provided with an external thread matching the internal thread on the threaded through hole; wherein the joint extending out of the threaded through hole is the first joint, and the joint rotatably connected to the piston plate is the end joint; the negative pressure cylinder is provided with a receiving groove for accommodating the joint on both sides of the threaded through hole.

[0007] Furthermore, among two adjacent joints, one end of one joint is a connecting groove, and one end of the other joint is a connecting plate, and the connecting plate is inserted into the connecting groove to realize a rotatable connection between the two adjacent joints.

[0008] Furthermore, a pivot is provided in the connecting groove, and an axial hole is provided on the connecting plate, and the pivot can movably pass through the axial hole.

[0009] Furthermore, a first arc-shaped protrusion is provided in the screw groove between two adjacent screw teeth on the external thread on the joint, and a second arc-shaped protrusion corresponding to the first arc-shaped protrusion is provided in the screw groove between two adjacent screw teeth on the internal thread on the threaded through hole, all of the first arc-shaped protrusions are arranged in a row along the axial direction of the joint, and all of the second arc-shaped protrusions are arranged in a row along the axial direction of the threaded through hole.

[0010] Furthermore, the first arc-shaped protrusion and the second arc-shaped protrusion each include an arc-shaped surface and a vertical surface; the direction of the arc-shaped surface of the first arc-shaped protrusion is opposite to the direction of the arc-shaped surface of the second arc-shaped protrusion.

[0011] Furthermore, a spiral drainage groove is provided on the radial end surface of the drainage tube, and a drainage port is provided on the side wall of the drainage groove.

[0012] Furthermore, a valve is provided on one end of the drainage pipe connected to the transition pipe.

[0013] Furthermore, a screw rod is provided at the end of the first joint.

[0014] Furthermore, both ends of the accommodating groove are provided with blind holes for accommodating the screw rod.

[0015] Furthermore, the end of the outflow port is provided with an external thread, both ends of the transition pipe are provided with external threads, and the outflow port and the transition pipe are connected via a threaded joint provided with an internal thread.

[0016] The utility model has the following beneficial effects: the arc-shaped protrusion in the piston rod screw groove cooperates with the arc-shaped protrusion in the threaded through hole to prevent the piston rod from reversing and can continuously and stably generate a negative pressure environment; it can drain multiple tissues at the same time, improves the use efficiency and reduces the operation steps of medical personnel; the piston rod can be folded and accommodated in the accommodating groove, which avoids the piston rod from being touched and improves the safety of use.

[0017] Additional aspects and advantages of the present invention will be partially given in the following description, which will become apparent from the following description or be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 This is a three-dimensional structural diagram of the anti-backflow negative pressure drain described in Example 1 of the utility model.

[0020] Figure 2 This is a top view of the structure of the anti-backflow negative pressure drain described in Example 1 of the utility model.

[0021] Figure 3 This is a top view of the structure of the anti-backflow negative pressure drain described in Example 1 of the utility model.

[0022] Figure 4 This is a structural diagram of the first joint of the anti-backflow negative pressure drain device described in an embodiment of the utility model.

[0023] Figure 5 This is a structural diagram of the second joint of the anti-backflow negative pressure drain device described in an embodiment of the utility model.

[0024] Figure 6 This is a structural diagram of the end joint of the anti-backflow negative pressure drain device described in an embodiment of the utility model.

[0025] Figure 7 This is a structural diagram of the first arc-shaped protrusion and the second arc-shaped protrusion of the anti-backflow negative pressure drain according to an embodiment of the utility model in the coordinated state. Figure 7 The middle (A) is the state diagram before the block. Figure 7 The middle (B) is the state diagram after blocking.

[0026] Figure 8 This is a diagram of the threaded connection state between the threaded through hole and the joint described in an embodiment of the utility model.

[0027] Fig. 9 This is a structural diagram of the drainage tube of the anti-backflow negative pressure drainer described in an embodiment of the utility model.

[0028] Fig.10 This is a top view of the structure of the anti-backflow negative pressure drain described in Example 2 of the utility model.

[0029] Among them: 1-negative pressure cylinder; 2-piston rod; 3-piston plate; 4-outlet; 5-transition pipe; 6-drainage pipe; 7-threaded through hole; 8-external thread; 9-first joint; 10-end joint; 11-accommodating groove; 12-connecting groove; 13-connecting plate; 14-pivot; 15-axial hole; 16-first arc-shaped protrusion; 17-second arc-shaped protrusion; 18-drainage groove; 19-drainage port; 20-valve; 21-screwing rod; 22-blind hole; 23-threaded joint; 24-second joint; 25-rotation port. DETAILED DESCRIPTION

[0030] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below by the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be interpreted as limiting the present invention.

[0031] Those skilled in the art will understand that, unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meaning as generally understood by those skilled in the art to which the present invention belongs.

[0032] It should also be understood that terms, such as those defined in commonly used dictionaries, should be understood to have a meaning consistent with that in the context of the prior art and will not be interpreted in an idealized or overly formal sense unless as defined herein.

[0033] Those skilled in the art will appreciate that, unless otherwise stated, the singular forms "a", "an", "said" and "the" used herein may also include plural forms. It should be further understood that the term "comprising" used in the specification of the present utility model refers to the presence of the features, integers, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements and / or groups thereof.

[0034] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification and the features of different embodiments or examples, unless they are contradictory.

[0035] In the description of this specification, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0036] In the description of this specification, the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present technology and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present technology.

[0037] Unless otherwise clearly specified or limited, the terms "installed", "connected", "connected", and "set" should be understood in a broad sense, for example, they can be fixedly connected or set, or detachably connected or set, or integrally connected or set. For ordinary technicians in this field, the specific meanings of the above terms in this technology can be understood according to specific circumstances.

[0038] To facilitate the understanding of the present invention, the present invention is further explained below with reference to specific embodiments in conjunction with the accompanying drawings, and the specific embodiments do not constitute a limitation on the embodiments of the present invention.

[0039] Those skilled in the art should understand that the drawings are merely schematic diagrams of embodiments, and the components in the drawings are not necessarily necessary for implementing the present invention. Example 1

[0040] like Figures 1 to 8 As shown, this embodiment 1 provides an anti-backflow negative pressure drain, including a negative pressure cylinder 1, a piston rod 2 is rotatably provided in the negative pressure cylinder 1, the end of the piston rod 2 is rotatably connected to a piston plate 3, the shape of the piston plate 3 matches the cross-sectional shape of the internal space of the negative pressure cylinder 1, in this embodiment, the negative pressure cylinder 1 is a rectangular parallelepiped, the outer layer of the piston plate 3 is a rubber layer, and the edge is tightly pressed against the inner wall of the negative pressure cylinder 1 to ensure that negative pressure can be generated. One end of the negative pressure cylinder 1 is provided with a plurality of outflow ports 4, such as Figure 1As shown, in this embodiment 1, three outflow ports 4 are provided, the ends of the outflow ports 4 are provided with external threads, both ends of the transition pipe 5 are provided with external threads, and the outflow ports 4 and the transition pipe 5 are connected by a threaded joint 23 provided with internal threads. When it is necessary to drain tissue fluid at one place, one of the outflow ports 4 is used to detachably connect a transition pipe 5 through a threaded joint 23, and the other end of the transition pipe 5 is detachably connected to the drainage tube 6, and the other two outflow ports 4 can be closed with threaded plugs with internal threads. When it is necessary to drain tissue fluid at three surgical sites, the three outflow ports 4 can be used at the same time. In this embodiment, in order to facilitate the patient to get out of bed and move during the drainage process, straps can be set on both sides of the negative pressure cylinder 1, and the negative pressure cylinder 1 can be tied to the patient's waist and abdomen with the straps.

[0041] Of course, in practical applications, the number of the flow outlets 4 is not limited to the above three, and those skilled in the art can set a suitable number of the flow outlets 4 according to specific circumstances.

[0042] In this embodiment, the rotation of the piston rod 2 can drive the piston plate 3 to move in the negative pressure cylinder 1. For example, when the piston rod 2 moves away from the outlet 4, negative pressure is generated in the space between the outlet 4 and the piston plate 3.

[0043] Specifically, a threaded through hole 7 is provided at one end of the negative pressure cylinder 1 opposite to the outflow port 4, and an internal thread is provided in the threaded through hole 7. The piston rod 2 is provided with an external thread 8 matching the internal thread of the threaded through hole 7. When the piston rod 2 is screwed, the relative rotation between the piston rod 2 and the threaded through hole 7 is converted into a linear movement of the piston rod 2 through the cooperation of the internal thread and the external thread 8. The linear movement of the piston rod 2 drives the piston plate 3 to move in the negative pressure cylinder 1. In order to prevent the piston rod 2 from being touched by the patient's body parts, the piston rod 2 is set in a foldable form, and a receiving groove 11 is provided on both sides of the threaded through hole 7 on the negative pressure cylinder 1 to accommodate the folded piston rod 2. In order to realize the foldability of the piston rod 2, the piston rod 2 is composed of a plurality of joints pivotally connected in sequence, and each of the joints is provided with an external thread 8 matching the internal thread on the threaded through hole 7; wherein, the joint extending out of the threaded through hole 7 is the first joint 9, and the joint rotatably connected to the piston plate 3 is the end joint 10. In order to facilitate the screwing of the piston rod 2 , a screwing rod 21 is provided at the end of the first joint 9 .

[0044] In addition, the piston rod 2 is configured to have multiple foldable joints, which can also correspond to the method of setting multiple outflow ports 4. For example, when only one outflow port 4 is needed for drainage, it is only necessary to screw the first joint 9 on the piston rod 2 out of the negative pressure cylinder 1, and then rotate and fold the first joint 9 and place it in the accommodating groove 11. At the same time, blind holes 22 for accommodating the screwing rod 21 are set at both ends of the accommodating groove 11.

[0045] Specifically, in order to realize the foldability between adjacent joints, one end of one of the two adjacent joints is a connecting groove 12, and one end of the other joint is a connecting plate 13, and the connecting plate 13 is inserted into the connecting groove 12 to realize the rotatable connection between the two adjacent joints. Specifically, a pivot 14 is provided in the connecting groove 12, and an axial hole 15 is provided on the connecting plate 13, and the pivot 14 can movably pass through the axial hole 15 to realize the pivot connection between the two adjacent joints.

[0046] like Figure 4 , Figure 5 , Figure 6 As shown, in this embodiment, the piston rod 2 is composed of three joints, which are a first joint 9, a second joint 24 and a terminal joint 10. The outermost end of the first joint 9 is a screw rod 21 ( Figure 4(not shown is only a partial structural diagram of the first joint 9, and the structure of the screw rod 21 is not shown), which extends out of the negative pressure cylinder 1. The bottom end of the first joint 9 is provided with a connecting groove 12, and a pivot 14 is arranged in the connecting groove 12. The top of the second joint 24 is provided with a connecting plate 13, and the connecting plate 13 is provided with an axial hole 15 for the pivot 14 to pass through, wherein the width of the connecting groove 12 is slightly larger than the thickness of the connecting plate 13 to ensure that the connecting groove 12 and the connecting plate 13 can rotate, and the diameter of the axial hole 15 is slightly larger than the diameter of the pivot 14. The bottom structure of the second joint 24 is the same as the bottom structure of the first joint 9, and the top structure of the terminal joint 10 is the same as the top structure of the second joint 24, so as to realize the pivot connection with the bottom end of the second joint 24. The bottom end of the terminal joint 10 is rotatably connected to the piston plate 3. Specifically, a rotation space (not shown in the figure) is set in the piston plate 3. A rotation port 25 is set in the middle of the piston plate 3. The rotation port is connected to the rotation space. The bottom end of the terminal joint 10 can move through the rotation port 25 in the middle of the piston plate 3 to extend into the rotation space to connect a rotation plate (not shown in the figure). The rotation space and the rotation plate are both circular, and the volume of the rotation plate is smaller than the volume of the rotation space. When in use, the user holds the screw rod 21 and rotates the first joint 9. The external thread on the first joint 9 matches the internal thread of the threaded through hole 7. The relative rotation between the first joint 9 and the threaded through hole 7 is converted into a linear movement of the first joint 9. The first joint 9 drives the second joint 24 to move linearly and rotate at the same time. When only one joint needs to be rotated, when the end of the first joint 9 moves out of the threaded through hole 7, the first joint 9 and the second joint 24 can be folded through the cooperation of the connecting groove 12 and the connecting plate 13. The first joint 9 is rotated and placed in the receiving groove 11. The blind hole 22 in the receiving groove 11 accommodates the screw rod 21. If the second joint 24 needs to be rotated out of the threaded through hole 7, the first joint 9 is not folded after being rotated out of the threaded through hole 7, and the rotation is continued until the second joint 24 is also moved out of the threaded through hole 7. After the second joint 24 and the terminal joint 10 are rotated and folded, the second joint 24 is accommodated in the receiving groove 11, and then the first joint 9 is folded in the opposite direction, and the depth of the receiving groove 11 can accommodate the folded joint. Figure 8 As shown, in order to ensure that the connection between two adjacent joints can be smoothly connected with the internal thread of the threaded through hole 7, the thickness of the threaded through hole 7 is greater than the length of the connection between the two adjacent joints. For example, after the external thread above the connecting groove 12 at the end of the first joint is screwed out of the threaded through hole 7, the external thread below the top connecting plate 13 of the second joint 24 has been screwed into the threaded through hole 7 at the same time.

[0047] In actual applications, the number of joints constituting the piston rod 2 is not limited to the above three. Those skilled in the art can set the number of joints according to actual conditions, such as 4 joints, 5 joints, or more.

[0048] like Figure 7 As shown, in order to prevent the thread rotation between the threaded through hole 7 and the piston rod 2 under the action of negative pressure, a first arc-shaped protrusion 16 is provided in the screw groove between two adjacent screw teeth on the external thread 8 on the joint, and a second arc-shaped protrusion 17 corresponding to the first arc-shaped protrusion 16 is provided in the screw groove between two adjacent screw teeth on the internal thread of the threaded through hole 7. All the first arc-shaped protrusions 16 are arranged in a row along the axial direction of the joint, and all the second arc-shaped protrusions 17 are arranged in a row along the axial direction of the threaded through hole. Specifically, the first arc-shaped protrusion 16 and the second arc-shaped protrusion 17 each include an arc-shaped surface and a vertical surface; the direction of the arc-shaped surface of the first arc-shaped protrusion 16 is opposite to the direction of the arc-shaped surface of the second arc-shaped protrusion 17. The vertical surface of the first arc-shaped protrusion 16 is perpendicular to the radial end surface of the screw groove on the joint; one end of the arc-shaped surface of the first arc-shaped protrusion 16 is connected to the top of the vertical surface of the first arc-shaped protrusion 16, and one end is connected to the radial end surface of the screw groove on the joint; the vertical surface of the second arc-shaped protrusion 17 is perpendicular to the radial end surface of the screw groove on the threaded through hole 7; one end of the arc-shaped surface of the second arc-shaped protrusion 17 is connected to the top of the vertical surface of the second arc-shaped protrusion 17, and one end is connected to the radial end surface of the screw groove on the joint. Figure 7 As shown in (A), when the piston rod 2 is screwed, the arc surface of the first arc-shaped protrusion 16 and the arc surface of the second arc-shaped protrusion 17 move relative to each other. Since the arc surface is a smooth arc, it will not hinder the relative rotation between the piston rod 2 and the threaded through hole 7. When the piston rod 2 is rotated to the desired position and the screwing of the piston rod 2 is stopped, as shown in FIG. Figure 7 As shown in (B), the vertical surface of the first arc-shaped protrusion 16 and the vertical surface of the second arc-shaped protrusion 17 are pressed against each other, thereby preventing the piston rod 2 from rotating under the action of negative pressure.

[0049] like Fig. 9 As shown, a spiral drainage groove 18 is provided on the radial end face of the drainage tube 6, and a drainage port 19 is provided on the side wall of the drainage groove 18. The function of the spirally rotating drainage groove 18 is to prevent the drainage tube 6 from being blocked by the tissue after the drainage tube 6 is buried in the tissue, and the tissue fluid can flow into the drainage tube 6 through the drainage port 19 on the side wall of the drainage groove 18, thereby ensuring the smooth drainage of the tissue fluid. In this embodiment, a valve 20 is provided on the end of the drainage tube 6 connected to the transition tube 6, and the valve can be closed when drainage is no longer needed. The end of the drainage tube 6 is a smooth arc, and a drainage port 19 is also provided on the arc surface of the end. In the process of pulling out the drainage tube 6, the drainage tube 6 is pulled out by rotating, and the direction of rotation is consistent with the spiral direction of the drainage groove 18, so as to prevent the drainage tube from injuring the tissue during the pulling out process. Example 2

[0050] like Fig.10In this embodiment 2, another anti-backflow negative pressure drain device is provided, which is different from the embodiment 1 in that one side or both sides of the negative pressure cylinder 1 are arc-shaped to match the arc of the side of the patient's waist and abdomen, so that it can be conveniently tied to the patient's waist and abdomen to ensure the patient's comfort.

[0051] Although the above describes the specific implementation methods of the utility model in conjunction with the accompanying drawings, it is not intended to limit the scope of protection of the utility model. Technical personnel in the relevant field should understand that on the basis of the technical solution disclosed in the utility model, various modifications or deformations that can be made by technical personnel in this field without creative work should be included in the scope of protection of the utility model.

Claims

1. A negative pressure drain device for preventing backflow, comprising a negative pressure cylinder (1), a piston rod (2) rotatably provided in the negative pressure cylinder (1), an end of the piston rod (2) rotatably connected to a piston plate (3), characterized in that: One end of the negative pressure cylinder (1) is provided with a plurality of outflow ports (4), each of the outflow ports (4) is detachably connected to a transition pipe (5), and the other end of the transition pipe (5) is detachably connected to a drainage pipe (6); The piston rod (2) is composed of a plurality of joints pivotally connected in sequence, the other end of the negative pressure cylinder (1) is provided with a threaded through hole (7), and each of the joints is provided with an external thread (8) matching the internal thread on the threaded through hole (7); wherein the joint extending out of the threaded through hole (7) is the first joint (9), and the joint rotatably connected to the piston plate (3) is the end joint (10); The negative pressure cylinder (1) is provided with a receiving groove (11) on both sides of the threaded through hole (7) for receiving the joint.

2. The anti-backflow negative pressure drain according to claim 1, characterized in that: Of the two adjacent joints, one end of one of the joints is a connection groove (12), and one end of the other joint is a connection plate (13); the connection plate (13) is inserted into the connection groove (12) to achieve a rotatable connection between the two adjacent joints.

3. The anti-backflow negative pressure drain according to claim 2, characterized in that: A pivot (14) is provided in the connection groove (12), and an axis hole (15) is provided on the connection plate (13), and the pivot (14) can movably pass through the axis hole (15).

4. The anti-backflow negative pressure drain according to claim 1, characterized in that: A first arc-shaped protrusion (16) is provided in the screw groove between two adjacent screw teeth on the external thread (8) on the joint, and a second arc-shaped protrusion (17) corresponding to the first arc-shaped protrusion (16) is provided in the screw groove between two adjacent screw teeth on the internal thread on the threaded through hole (7), all of the first arc-shaped protrusions (16) are arranged in a row along the axial direction of the joint, and all of the second arc-shaped protrusions (17) are arranged in a row along the axial direction of the threaded through hole.

5. The anti-backflow negative pressure drain according to claim 4, characterized in that: The first arc-shaped protrusion (16) and the second arc-shaped protrusion (17) both comprise an arc-shaped surface and a vertical surface; the direction of the arc-shaped surface of the first arc-shaped protrusion (16) is opposite to the direction of the arc-shaped surface of the second arc-shaped protrusion (17).

6. The anti-backflow negative pressure drain according to claim 1, characterized in that: A spiral drainage groove (18) is provided on the radial end surface of the drainage tube (6), and a drainage port (19) is provided on the side wall of the drainage groove (18).

7. The anti-backflow negative pressure drain according to claim 1, characterized in that: A valve (20) is provided on one end of the drainage pipe (6) that is connected to the transition pipe (5).

8. The anti-backflow negative pressure drain according to claim 1, characterized in that: A screw rod (21) is provided at the end of the first joint (9).

9. The backflow prevention negative pressure drain according to claim 8, characterized in that: Blind holes (22) for accommodating the screw rod (21) are provided at both ends of the accommodating groove (11).

10. The backflow prevention negative pressure drain according to claim 1, characterized in that: The end of the outflow port (4) is provided with an external thread, and both ends of the transition pipe (5) are provided with external threads. The outflow port (4) and the transition pipe (5) are connected via a threaded joint (23) provided with an internal thread.

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