Medical connector with tube

Abstract

The adhesive used to secure the connector to the tube prevents the flow path from narrowing. [Solution] The connector 1 comprises a connecting portion 10 that is connected to a mating connector, and a base portion 20 having a through hole 21 that communicates with the connecting portion 10. The inner circumferential surface of the through hole 21 has a cylindrical portion 23 having an inner diameter larger than the outer diameter of the tube 50, and a conical portion 24 adjacent to the cylindrical portion 23 on the connecting portion 10 side and whose inner diameter decreases toward the connecting portion 10. The tube 50 is inserted into the through hole 21 such that the tip 51 or outer circumferential surface 53 of the tube 50 abuts against the conical portion 24.

Description

Technical Field

[0001] The present invention relates to a medical connector with a tube, in which a connector is provided at the tip of the tube.

Background Art

[0002] When performing enteral nutrition, infusion, blood circulation, etc., a hollow flexible tube is used to form a flow path through which a liquid flows. A connector is provided at the tip of the tube. The tube is inserted into a through hole provided in the base portion of the connector. The inner peripheral surface of the through hole has a cylindrical surface with an inner diameter slightly larger than the outer diameter of the tube. An annular abutting surface that protrudes radially inward from the cylindrical surface is provided at a position at a predetermined depth from the opening of the through hole. The tube is inserted into the through hole until its front end surface abuts axially against the abutting surface. The tube is fixed to the base portion by an adhesive applied to the gap between the tube and the inner peripheral surface of the through hole (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] The abutment surface of a connector is an annular flat surface aligned with a plane perpendicular to the axis of the through-hole. In contrast, the end surface of a tube is a cut surface formed by simply cutting the tube to a predetermined length, and is therefore not necessarily a flat surface perpendicular to the longitudinal direction of the tube. For this reason, when the end surface of the tube abuts against the abutment surface in the axial direction, a gap may be formed between the abutment surface and the end surface of the tube. Uncured liquid adhesive enters the flow path through this gap. Subsequently, when the adhesive hardens, the flow path is narrowed by the adhesive, which hinders the flow of the liquid.

[0005] The objective of this invention is to prevent the flow path from narrowing due to the adhesive used to fix the connector to the tube. [Means for solving the problem]

[0006] The present invention relates to a medical connector with a tube, wherein a connector is provided at the tip of the tube. The connector comprises a connecting portion that is connected to a mating connector, and a base portion having a through hole communicating with the connecting portion. The inner circumferential surface of the through hole has a cylindrical portion having an inner diameter larger than the outer diameter of the tube, and a conical portion adjacent to the cylindrical portion on the side of the connecting portion, with the inner diameter decreasing toward the connecting portion. The tube is inserted into the through hole such that the tip or outer circumferential surface of the tube abuts against the conical portion. [Effects of the Invention]

[0007] In this invention, the tip or outer surface of the tube is in contact with the conical portion of the through hole. Therefore, uncured adhesive applied to the gap between the tube and the inner surface of the through hole cannot flow beyond the tip of the tube's outer surface into the liquid flow path. Thus, according to this invention, it is possible to prevent the flow path from narrowing due to the adhesive. [Brief explanation of the drawing]

[0008] [Figure 1]Figure 1 is a perspective view of a connector according to one embodiment of the present invention, as seen from the connection side. [Figure 2] Figure 2 is a perspective view of the connector shown in Figure 1, seen from the base side. [Figure 3] Figure 3 is a cross-sectional view of the connector shown in Figure 1. [Figure 4] Figure 4 is a cross-sectional view of a connector with a tube according to one embodiment of the present invention. [Figure 5A] Figure 5A is a cross-sectional view showing one step in the manufacturing process of the tube-attached connector shown in Figure 4. [Figure 5B] Figure 5B is a cross-sectional view showing another step in the manufacturing process of the tubed connector shown in Figure 4. [Figure 5C] Figure 5C is a cross-sectional view showing yet another step in the manufacturing process of the tubed connector shown in Figure 4. [Figure 6] Figure 6 is a cross-sectional view of a tube-equipped connector according to a comparative example. [Figure 7] Figure 7 is a cross-sectional view of a connector according to one embodiment of the present invention, provided on a relatively thick tube. [Modes for carrying out the invention]

[0009] In one aspect of the present invention, a liquid-tight seal that is continuous in an annular manner in the circumferential direction may be formed at the tip of the outer surface of the tube or between the outer surface and the conical portion. Such an aspect is advantageous in preventing the flow path from narrowing due to the adhesive.

[0010] In one aspect of the present invention, the leading edge of the outer surface of the tube may be in contact with the conical portion. This aspect is advantageous in reducing variations in the insertion depth of the tube into the through hole.

[0011] In one aspect of the present invention, an adhesive may be applied between the tube and the inner circumferential surface of the through hole. This aspect is advantageous for securing a connector to the end of the tube.

[0012] In one aspect of the present invention, the adhesive may be a UV adhesive. Such an aspect is advantageous for efficiently performing the step of adhesively fixing the connector to the tube.

[0013] In one aspect of the present invention, the taper angle of the tapered surface constituting the conical portion may be 20 degrees or more and 60 degrees or less. The fact that the taper angle is 20 degrees or more is advantageous for suppressing variations in the insertion depth of the tube into the through hole, and further variations in the length of the tube led out from the connector, which are caused by variations in the outer diameter of the tube. Also, the fact that the taper angle is 60 degrees or less is advantageous for facilitating the manufacture of the connector with a tube in which the flow path is not narrowed by the adhesive.

[0014] In one aspect of the present invention, the inner peripheral surface of the through hole may further include a guide portion that is adjacent to the cylindrical portion on the side opposite to the connection portion and has an inner diameter that increases toward the tip of the base portion. Such a guide portion, firstly, facilitates inserting the tube into the through hole, and secondly, functions as a liquid pool for storing the uncured adhesive.

[0015] In one aspect of the present invention, the cylindrical portion may be longer than the conical portion. Such an aspect is advantageous for improving the adhesive strength of the tube to the base portion. Also, such an aspect facilitates bringing the tip or the outer peripheral surface of the outer peripheral surface of the tube into close contact with the conical portion even if the tube has a curl, which is advantageous for preventing the flow path from being narrowed by the adhesive.

[0016] In one aspect of the present invention, the outer diameter of the tube may be 3 mm or less. The effect of the present invention of preventing the flow path from being narrowed by the adhesive is more显著 when the tube has a small diameter.

[0017] In one aspect of the present invention, the entire connector may be integrally formed as a single part. Such an aspect is advantageous for efficiently manufacturing the connector at a low cost.

[0018] In one aspect of the present invention, the connecting portion may include a hollow cylindrical tubular portion, an internal female tapered surface provided on the inner peripheral surface of the tubular portion and having an increasing inner diameter toward the tip of the tubular portion, and a spiral protrusion provided on the outer peripheral surface of the tubular portion. According to such an aspect, the present invention can be applied to an extension tube that can be connected to a nasal catheter.

[0019] Hereinafter, the present invention will be described in detail while showing preferred embodiments. However, it is needless to say that the present invention is not limited to the following embodiments. Each drawing referred to in the following description shows, for convenience of explanation, the main members constituting the embodiment of the present invention in a simplified manner. Therefore, the present invention may include any members not shown in the following drawings. Also, within the scope of the present invention, the members shown in the following drawings can be changed or omitted. In different drawings, the same or corresponding members are denoted by the same reference numerals. For such members, duplicate descriptions are omitted, and the description of the preceding drawings should be appropriately referred to.

[0020] In the present invention, the "axis" of a member (such as a connector, a connecting portion, a base portion, a through-hole, a tube, etc.) means the central axis of the member. The "axis" passes through the center of a circle included in the member and / or coincides with the central axis of a cylinder or a cone (taper) included in the member. The direction along a straight line orthogonal to the axis is referred to as the "radial direction". In the radial direction, the side closer to the axis is referred to as the "inner" side, and the side farther from the axis is referred to as the "outer" side. The direction of rotation around the axis is referred to as the "circumferential direction". In the drawings cited in the following description, the illustration of the axis is omitted for simplicity of the drawings.

[0021] FIG. 1 and FIG. 2 are perspective views of a connector 1 according to an embodiment of the present invention. FIG. 3 is a cross-sectional view of the connector 1 along a plane including the axis (not shown) of the connector 1. The connector 1 includes a connecting portion 10 at one end and a base portion 20 at the other end. The connecting portion 10 and the base portion 20 are coaxially arranged.

[0022] The connecting portion 10 has a hollow cylindrical tubular portion (female member) 11. The inner circumferential surface of the tubular portion 11 has a tapered surface (so-called female tapered surface) 12 in which the inner diameter increases towards the tip of the tubular portion 11. The outer circumferential surface 13 of the tubular portion 11 is a cylindrical surface. A threaded projection (male screw) 15 is formed on the outer circumferential surface 13. Connector 1 is a female connector equipped with a tubular portion 11 as a female member. The connecting portion 10 can be repeatedly connected to and disconnected from a mating connector (not shown).

[0023] As shown in Figure 3, a through-hole 21, coaxial with the connecting portion 10 (or tubular portion 11), penetrates the base portion 20. The through-hole 21 communicates with the connecting portion 10 (or the lumen of the tubular portion 11). The inner circumferential surface of the through-hole 21 has, in order from the tip of the base portion 20 (the end opposite to the connecting portion 10, the lower end in Figure 3) toward the connecting portion 10, a guide portion 22, a cylindrical portion 23, a conical portion 24, and a small diameter portion 25.

[0024] The guide portion 22 is a tapered surface (a so-called female tapered surface) whose inner diameter increases towards the tip of the base portion 20. The portion of the guide portion 22 with the largest diameter constitutes the opening end of the through hole 21.

[0025] The cylindrical portion 23 is adjacent to the guide portion 22 on the connection portion 10 side. The cylindrical portion 23 is a cylindrical surface whose inner diameter is constant in the axial direction of the connector 1 (or the longitudinal direction of the through hole 21). The inner diameter of the cylindrical portion 23 coincides with the minimum inner diameter of the guide portion 22 (the inner diameter of the guide portion 22 at the end of the cylindrical portion 23 side).

[0026] The conical portion 24 is adjacent to the cylindrical portion 23 on the side facing the connection portion 10. The conical portion 24 is a tapered surface (a so-called female tapered surface) whose inner diameter decreases towards the connection portion 10. The tapered surfaces constituting the conical portion 24 are continuous in an annular shape in the circumferential direction. The maximum inner diameter of the conical portion 24 (the inner diameter at the end of the conical portion 24 on the side facing the cylindrical portion 23) is the same as the inner diameter of the cylindrical portion 23.

[0027] The small-diameter portion 25 is adjacent to the conical portion 24 on the connection portion 10 side. The small-diameter portion 25 is not limited, but its inner diameter may be a cylindrical surface with a constant inner diameter in the axial direction of the connector 1 (or the longitudinal direction of the through hole 21), or a tapered surface with an inner diameter that increases toward the conical portion 24 or the connection portion 10. The inner diameter of the small-diameter portion 25 at the end on the conical portion 24 side coincides with the minimum inner diameter of the conical portion 24 (the inner diameter of the conical portion 24 at the end on the small-diameter portion 25 side).

[0028] In this invention, at least one of the guide portion 22 and the small diameter portion 25 may have a different configuration from that of this embodiment. Alternatively, at least one of the guide portion 22 and the small diameter portion 25 may be omitted.

[0029] The outer surface of the base portion 20 is provided with a pair of substantially flat grip surfaces 27 (only one grip surface 27 is visible in Figures 1 and 2). The pair of grip surfaces 27 are substantially flat surfaces perpendicular to the radial direction of the connector 1 and are parallel to each other. The grip surfaces 27 facilitate the operator in grasping the connector 1 and applying rotational force. However, in this invention, it is not essential that the base portion 20 has grip surfaces 27. The external shape of the base portion 20 is not limited to this embodiment and can be configured arbitrarily. For example, the base portion 20 may have a simple substantially cylindrical shape with a through hole 21 formed therein. Alternatively, the base portion 20 may consist of a substantially cylindrical connecting cylinder with a through hole 21 formed therein, and a pair of plate-like bodies projecting radially in opposite directions from the outer surface of the connecting cylinder. The pair of plate-like bodies facilitate the operator in grasping the connector 1 and applying rotational force.

[0030] A flange 29 is provided between the connecting portion 10 and the base portion 20. The flange 29 protrudes radially outward from the connecting portion 10 (or tubular portion 11) and the base portion 20. In this embodiment, the flange 29 is a flat plate with a substantially circular shape in plan view along the axis of the connector 1. However, in the present invention, the plan view shape of the flange 29 is not limited to substantially circular, but may be polygonal (e.g., hexagonal, quadrilateral) or elliptical. The flange 29 is advantageous in preventing fingers from touching and contaminating the connecting portion 10 (especially the outer surface of the tubular portion 11 or the screw-shaped projection 15) when the base portion 20 (especially its grip surface 27) is grasped with fingers. In the present invention, the flange 29 may be omitted.

[0031] The material of connector 1 is not limited, but a hard material (rigid material) having sufficient mechanical strength (rigidity) to not be substantially deformed by external force can be used. For example, resin materials such as polypropylene, acrylonitrile-butadiene-styrene copolymer, polycarbonate, polyacetal, polystyrene, polyamide, polyethylene, and rigid polyvinyl chloride can be used. In this invention, from the viewpoint of preventing the occurrence of chemical cracks and preventing the elution of bisphenol A, chemically stable polypropylene is preferred as the material of connector 1. Connector 1 can be manufactured integrally as a single part using the above resin material by injection molding or the like. Connector 1 is preferably transparent or light-transmitting.

[0032] As shown in Figure 4, the connector 1 is provided at the tip of a flexible tube 50. The tube 50 is fixed to the base portion 20 of the connector 1 via adhesive 60.

[0033] The tube 50 has a hollow cylindrical shape. In a cross-section of the tube 50 along a plane perpendicular to the longitudinal direction of the tube 50, the outer circumferential surface 53 and the inner circumferential surface of the tube 50 are concentric circles. The outer and inner diameters of the tube 50 are constant in the longitudinal direction of the tube 50, except for variations due to manufacturing tolerances. The material of the tube 50 is not limited, but resins such as polyurethane, silicone, polyethylene, styrene elastomer, and polybutadiene can be used. The tube 50 can be continuously manufactured using the above materials, for example, by extrusion molding. The tube 50 can be relatively easily deformed by bending and radial compression by applying an external force, and then returns to its initial state when the external force is removed.

[0034] The adhesive 60 can be selected from known adhesives according to the materials of the connector 1 and tube 50. In the present invention, the adhesive 60 is not limited, but for example, UV adhesives, epoxy adhesives, etc., can be used.

[0035] The manufacturing method for the connector 1 with tube 50 shown in Figure 4 will be described.

[0036] First, prepare the connector 1 and tube 50 as shown in Figure 5A. The outer diameter of the tube 50 is smaller than the inner diameter of the cylindrical portion 23 (i.e., the maximum inner diameter of the conical portion 24) and larger than the minimum inner diameter of the conical portion 24. The tube 50 is cut to a predetermined length. The cut surface of the tube 50 is called the tip surface 52. The boundary between the outer peripheral surface 53 and the tip surface 52 of the tube 50 is called the outer peripheral surface tip 51. Hold the connector 1 with the base portion 20 facing upwards and the axis of the connector 1 parallel to the vertical direction using a jig or the like (not shown). Position the tip of the tube 50 coaxially opposite the opening of the through hole 21. Then, insert the tip of the tube 50 into the through hole 21 from the guide portion 22. The female taper surface of the guide portion 22 guides the tip of the tube 50 into the through hole 21. Since the tube 50 has a smaller diameter than the cylindrical portion 23, the tube 50 can be inserted into the through hole 21 relatively easily.

[0037] After a while, as shown in Figure 5B, the outer circumferential tip 51 of the tube 50 comes into contact with the conical portion 24. Further pushing the tube 50 into the through hole 21 causes the outer circumferential tip 51 of the tube 50 to slide along the conical portion 24 toward the connecting portion 10, thereby compressing and deforming the tip of the tube 50 radially so that the outer diameter at the outer circumferential tip 51 becomes smaller. The outer circumferential tip 51 and a portion of the outer circumferential surface 53 of the tube 50 (the portion of the outer circumferential surface 53 near the outer circumferential tip 51, hereinafter referred to as the "outer circumferential surface near the tip") are in liquid-tight contact with the conical portion 24, and a liquid-tight seal is formed between the outer circumferential tip 51 and the outer circumferential surface near the tip and the conical portion 24 in a circumferentially continuous annular shape. The outer circumferential surface 53 of the tube 50 (excluding the portion in contact with the conical portion 24) and the inner circumferential surface of the through hole 21 are spaced radially apart, and a gap (radial gap) 57 is formed between them.

[0038] Next, as shown in Figure 5C, uncured liquid adhesive 65 is applied to the gap 57 between the tube 50 and the inner circumferential surface of the through hole 21. More specifically, the adhesive 65 is dripped into the annular recess (see Figure 5B) formed by the tube 50 and the female taper surface of the guide portion 22. The guide portion 22 functions as a liquid reservoir for storing the liquid adhesive 65. The adhesive 65 flows from the guide portion 22 towards the tip of the tube 50 through the gap 57. However, since a liquid-tight seal is formed between the tip 51 of the outer circumferential surface of the tube 50 and the outer circumferential surface near the tip and the conical portion 24, the adhesive 65 cannot flow beyond the tip 51 of the outer circumferential surface toward the connection portion 10.

[0039] Next, the adhesive 65 is cured. For example, if the adhesive 65 is a UV adhesive, the adhesive 65 is cured by irradiating it with UV light. Thus, the connector 1 with tube 50 shown in Figure 4 is obtained.

[0040] Connector 1 with tube 50 can be used, but is not limited, as an extension tube (sometimes called an "enteral nutrition set") connected to a nasogastric catheter used for enteral nutrition. A nasogastric catheter has a male connector at the proximal end of a flexible tube. The tube of the nasogastric catheter is inserted through the patient's nasal cavity, and its tip reaches the stomach. The nasogastric catheter is left in place in the patient for an extended period. When performing enteral nutrition, connector (female connector) 1 is connected to the male connector of the nasogastric catheter. The male connector comprises a hollow cylindrical tubular part (male member), a tapered surface (male taper surface) on the outer surface of the tubular part, and a female thread surrounding the tubular part (see, for example, Patent Document 2). When the connection part 10 of connector 1 is connected to the male connector, the tubular part (male member) is inserted into the tubular part (female member) 11, the male taper surface is liquid-tightly tapered-fitted to the female taper surface 12, and the female thread is screwed into the screw projection 15. Liquid nutritional supplements are administered to the patient by passing them through tube 50, connector 1, and a nasogastric catheter in that order.

[0041] As described above, the connector 1 of this embodiment has a cylindrical portion 23 having an inner diameter larger than the outer diameter of the tube 50 and a conical portion 24 whose inner diameter decreases toward the connection portion 10 on the inner circumferential surface of the through hole 21 communicating with the connection portion 10. The effects of the connector 1 with this configuration will be explained in comparison with a comparative example.

[0042] Figure 6 is a cross-sectional view of a connector 901 with a tube 50 according to a comparative example. The connector 901 has a stop surface 924 instead of the conical portion 24 of the connector 1. The stop surface 924 protrudes radially inward from the cylindrical portion 23 and is an annular flat surface along a plane perpendicular to the axis of the connector 901.

[0043] The connector 901 with tube 50 shown in Figure 6 is assembled in substantially the same manner as the connector 1 with tube 50 (see Figures 4, 5A to 5C). That is, the tube 50 is inserted into the through hole 21 until its tip surface 52 abuts against the abutment surface 924 in the axial direction. The abutment surface 924 defines the insertion depth of the tube 50 into the through hole 21. Next, uncured liquid adhesive is applied to the radial gap 57 between the tube 50 and the inner circumferential surface of the through hole 21 via the guide portion 22. Then, the adhesive is cured. The tube 50 is fixed to the base portion 20 of the connector 901 via the adhesive 60.

[0044] Generally, the tube 50 is manufactured by cutting a long tube, which is continuously produced by extrusion molding, to a predetermined length. The end surface 52 of the tube 50 is the cut surface formed by the cutting blade. The end surface 52 formed in this way is not necessarily a flat surface perpendicular to the longitudinal direction of the tube 50. For example, the end surface 52 may have irregularities, or it may be slightly inclined with respect to the longitudinal direction of the tube 50, or burrs generated during cutting may extend from the end surface 52. Furthermore, the shape of this end surface 52 may differ from tube to tube. For this reason, even when the end surface 52 is brought into contact with the abutment surface 924, the end surface 52 and the abutment surface 924 may not be in close contact around the entire circumference, and discrete gaps (axial gaps) 59 may be formed between them. In this state, if uncured liquid adhesive is applied to the radial gap 57 between the tube 50 and the inner surface of the through hole 21, the adhesive may flow through the axial gap 59 into the liquid flow channel (for example, the lumen of the tube 50 or the lumen of the small diameter section 25). The adhesive is then cured. The adhesive 62 that has hardened after flowing into the flow channel narrows the channel.

[0045] In contrast, the connector 1 of this embodiment has a conical portion 24 on the inner circumferential surface of the through hole 21 that is adjacent to the connection portion 10 side relative to the cylindrical portion 23. As shown in Figure 5B, the tube 50 is inserted into the through hole 21, and its outer circumferential tip 51 and outer circumferential surface (especially the outer circumferential surface near the tip) 53 are in contact with the conical portion 24. Even if the tip surface 52 of the tube 50 is not a flat surface perpendicular to the longitudinal direction of the tube 50, if the tube 50 is pushed into the through hole 21 so that the outer circumferential tip 51 is slightly reduced in diameter, the outer circumferential tip 51 and outer circumferential surface (especially the outer circumferential surface near the tip) 53 can be easily made to adhere to the conical portion 24 in a liquid-tight manner. In this state, if an uncured liquid adhesive 65 is applied to the radial gap 57 between the tube 50 and the inner circumferential surface of the through hole 21, the adhesive 65 cannot flow beyond the outer circumferential tip 51 (see Figure 5C). Therefore, unlike the comparative example connector 901, the connector 1 of this embodiment does not suffer from the problem of the liquid flow path being narrowed by the hardened adhesive 60.

[0046] In the comparative example connector 901 (see Figure 6), the axial gap 59 may be eliminated if the tube 50 is firmly pressed into the through hole 21 before applying the uncured adhesive. In this state, if the uncured liquid adhesive is applied to the radial gap 57, it may be possible to prevent the adhesive from flowing into the flow path, similar to connector 1. However, in connector 901, if the pressing force applied to the tube 50 is released, the axial gap 59 reappears due to the repulsive force of the tube 50. Therefore, the tube 50 must be continuously pressed firmly into the through hole 21 from before the application of the uncured liquid adhesive until the adhesive hardens, in order to prevent the formation of the axial gap 59. This complicates the process of bonding and fixing the tube 50 to connector 901. If the pressing force of the tube 50 against the through hole 21 is not properly controlled, defective products with narrowed flow paths due to the adhesive will occur. Consequently, the connector 901 with the tube 50 is complicated to manufacture and has a low yield.

[0047] In contrast, in the connector 1 of this embodiment, when the tube 50 is pushed into the through hole 21, a frictional force is generated between the outer surface tip 51 and the outer surface near the tip and the conical portion 24 due to the repulsive force of the reduced diameter outer surface tip 51 and its vicinity (see Figure 5B). Subsequently, even if the pushing force applied to the tube 50 is released, this frictional force restricts the movement of the outer surface tip 51 relative to the conical portion 24. A liquid-tight seal between the outer surface tip 51 and the outer surface near the tip and the conical portion 24 is maintained. Even if uncured liquid adhesive is applied to the radial gap 57 after the tube 50 has been pushed into the through hole 21 and the pushing force has been released, the adhesive 65 cannot flow beyond the outer surface tip 51. The possibility of defective products with narrowed flow paths due to adhesive is low. For this reason, the process of bonding and fixing the tube 50 to the connector 1 is easy. The connector 1 with the tube 50 is easy to manufacture and can be produced at low cost with a high yield.

[0048] Generally, there is a manufacturing tolerance in the outer diameter of the tube 50. That is, the actual outer diameter of the tube 50 is allowed to vary by a certain range (tolerance) from the standard outer diameter. Figure 7 is a cross-sectional view of the connector 1 provided at the end of a thick tube 55. The outer diameter of the tube 55 is slightly thicker than that of the tube 50 in Figure 4, but it is within the tolerance range for the outer diameter of the tube applied to the connector 1. As can be easily understood by comparing it with Figure 4, in Figure 7, the outer peripheral tip 51 and the outer peripheral surface (especially the outer peripheral surface near the tip) 53 of the tube 55 are in contact with the conical portion 24 at a position close to the cylindrical portion 23. It is preferable that the conical portion 24 be configured such that even if the outer diameter of the tube varies within tolerance, the outer peripheral tip 51 or outer peripheral surface 53 of the tube (50, 55) always contacts the conical portion 24. This is advantageous in preventing the occurrence of defective products in which the flow path is narrowed by the adhesive.

[0049] The conical portion 24 is preferably configured to abut against the outer peripheral tip 51 of the tube 50. The conical portion 24, configured in this way, defines the insertion depth of the tube into the through-hole 21, similar to the abutment surface 924 of the comparative example connector 901 (see Figure 6). However, if the outer diameter of the tube varies within tolerance, the insertion depth of the tube into the through-hole 21 will change. The smaller the taper angle of the female taper surface constituting the conical portion 24, the greater the variation in the insertion depth of the tube into the through-hole 21 due to variations in the outer diameter of the tube. This increases the variation in the length of the tube led out from the connector 1. Therefore, while the taper angle of the conical portion 24 is not limited, it is preferably 20 degrees or more, and more preferably 30 degrees or more. This is advantageous in suppressing variations in the length of the tube led out from the connector 1 when using a tube with an outer diameter tolerance. For example, it is desirable that the variation in the total length of the extension tube connected to the nasogastric catheter be kept below a predetermined range. This requirement can be met if the taper angle of the conical portion 24 satisfies the above numerical range. Generally, it is preferable that the variation in the insertion depth of the tube into the through hole 21, due to variations in the outer diameter of the tube, is 2 mm or less, and more preferably 1 mm or less.

[0050] On the other hand, if the taper angle of the female taper surface constituting the conical portion 24 is large, when the pushing force applied to the tube 50 is released after the tube 50 has been pushed into the through hole 21 (see Figure 5B), the repulsive force of the tube 50 increases the likelihood that the outer peripheral tip 51 will move along the conical portion 24 toward the guide portion 22 (i.e., the tube 50 will be pushed out of the through hole 21). In this case, the liquid-tightness of the seal between the outer peripheral tip 51 and the outer peripheral surface near the tip and the conical portion 24 decreases, and the likelihood of defective products with narrowed flow paths due to the adhesive increases. Therefore, although the taper angle of the conical portion 24 is not limited, it is preferable that it be 60 degrees or less, and more preferably 45 degrees or less. This facilitates the manufacture of tube-type connectors in which the flow paths are not narrowed by the adhesive.

[0051] There are no restrictions on the axial dimensions of each part of the through hole 21. However, the cylindrical portion 23 is preferably longer than the conical portion 24, and more preferably, the cylindrical portion 23 is at least three times longer than the conical portion 24. Here, the "length" of the cylindrical portion 23 and the conical portion 24 refers to the dimension along the axial direction (longitudinal direction of the through hole 21) of the cylindrical portion 23 and the conical portion 24. A relatively long cylindrical portion 23 is advantageous in improving the adhesive strength of the tube 50 to the base portion 20. In addition, a long cylindrical portion 23 facilitates straightening the coiled tube 50 within the cylindrical portion 23, making it easier to form a circumferentially continuous, annular, liquid-tight seal between the outer peripheral surface tip 51 and the outer peripheral surface near the tip and the conical portion 24. Therefore, a long cylindrical portion 23 is also advantageous in preventing the flow path from narrowing due to the adhesive.

[0052] The outer diameter of tube 50 is not limited and can be arbitrarily set according to the application of tube 50. However, in this invention, the outer diameter of tube 50 is preferably 3 mm or less. When the outer diameter of tube 50 becomes smaller, the inner diameter of the flow path (for example, tube 50 or small diameter section 25) also becomes smaller, and the cross-sectional area of ​​the flow path through which the liquid flows becomes smaller. Such a small cross-sectional area flow path can easily become blocked by even a small amount of adhesive adhering to the flow path. Therefore, the smaller the outer diameter of tube 50, the greater the significance of applying this invention, which has the effect of preventing the flow path from narrowing due to adhesive.

[0053] In the above embodiment, the outer peripheral tip 51 of the tube 50 was positioned within the conical portion 24, and both the outer peripheral tip 51 and the outer peripheral surface (particularly the outer peripheral surface near the tip) 53 of the tube 50 were in contact with the conical portion 24. However, the present invention is not limited thereto.

[0054] The present invention includes a configuration in which the outer peripheral tip 51 abuts against the conical portion 24, but the outer peripheral surface 53 does not abut against the conical portion 24. Such a configuration may occur, for example, when the force with which the tube 50 is pressed into the through hole 21 of the connector 1 is insufficient before the tube 50 is adhesively fixed to the connector 1.

[0055] The present invention also includes a configuration in which the outer circumferential surface 53 is in contact with the conical portion 24, but the outer circumferential surface tip 51 is not in contact with the conical portion 24. Such a configuration may occur, for example, when a long tube is cut to obtain a tube 50 of a predetermined length, and the outer circumferential surface tip 51 is missing. Alternatively, such a configuration may occur when the tube 50 is inserted into the through hole 21 with the outer circumferential surface tip 51 extending beyond the conical portion 24 (for example, such that the outer circumferential surface tip 51 is located within the small diameter portion 25). In this case, the tube 50 is deformed to reduce in diameter at the smallest inner diameter portion of the conical portion 24, and the outer circumferential surface 53 of the tube 50 comes into contact with the conical portion 24 near the smallest inner diameter portion. It is preferable that the tube 50 does not protrude into the lumen of the tubular portion 11.

[0056] Although the connector 1 in the above embodiment was a female connector that can be connected to the male connector of a nasogastric catheter used for enteral nutrition, the present invention can also be applied to connectors for other uses. Specifically, the connector of the present invention may be a connector used to form a flow path for any liquid in the medical field, such as enteral nutrition other than nasogastric, infusion, or blood circulation. The configuration of the connector's connection part can be appropriately changed depending on the application of the connector and the mating connector to which the connection part is connected. The connector of the present invention may be a male connector (see, for example, Patent Document 2) in which a cylindrical male member that can be inserted into and removed from the mating connector is provided at its connection part. Depending on the application of the connector, the diameter, length, material, etc. of the tube can be appropriately changed.

[0057] The connector 1 described above was equipped with a screw structure (screw projection 15) as a locking mechanism to maintain the connection state with the mating connector, but the connector of the present invention may be equipped with a locking mechanism other than a screw structure. For example, the locking mechanism may be a lever locking mechanism consisting of a swingable lever provided with a claw that can engage with the mating connector. Alternatively, the locking mechanism may be an engagement structure (claw, recess, groove, step, etc.) provided on the mating connector that can engage with the claw of the lever locking mechanism. The connector of the present invention may not be equipped with such a locking mechanism.

[0058] In the above embodiment, a connector 1 was provided at one end of the tube 50. In the present invention, the configuration of the other end of the tube is arbitrary. For example, the other end of the tube may be provided with any connector or a component other than a connector (for example, a container for storing liquid).

[0059] In the above embodiment, the entire connector 1 was integrally constructed as a single component using the same resin material. Such a connector 1 is advantageous for efficient and low-cost manufacturing. However, the connector of the present invention is not limited to this. For example, the connecting portion that connects to the mating connector and the base portion to which the tube is bonded may be made of different materials. The connecting portion may be made of a material that has toughness and durability so that it can be repeatedly connected to and disconnected from the mating connector. On the other hand, the base portion may be made of a material that has good adhesion to the tube. The connecting portion and the base portion made of different materials may be integrated by two-color molding, or they may be manufactured separately and then combined and integrated. [Industrial applicability]

[0060] The present invention can be widely used in the medical field as a tubed connector for constructing a fluid flow path. There are no restrictions on the type of fluid; for example, it may be a liquid nutritional supplement, drug solution, intravenous fluid, blood, etc. [Explanation of symbols]

[0061] 1 Connector 10 Connection part 11 Tubular part 12 Mess taper surface 15 Spiral process 20 Base part 21 Through hole 22 Information Department 23 Cylindrical section 24 Cone section 25 Small diameter section 50, 55 tubes 51 Outer surface tip of the tube 52. The tip surface of the tube 53 Outer surface of the tube 60 Adhesives 65 Uncured adhesive

Claims

1. A medical connector with a tube, in which a connector is provided at the tip of the tube, The connector comprises a connecting portion that is connected to a mating connector, and a base portion having a through hole that communicates with the connecting portion. The inner circumferential surface of the through hole is A cylindrical portion having an inner diameter larger than the outer diameter of the tube, It has a conical portion adjacent to the cylindrical portion on the connection side, and whose inner diameter decreases toward the connection portion, A medical connector with a tube, characterized in that the tube is inserted into the through-hole such that the tip or outer surface of the tube contacts the conical portion.

2. A medical connector with a tube according to claim 1, wherein a liquid-tight seal is formed in a circumferentially continuous annular manner at the tip of the outer surface of the tube or between the outer surface and the conical portion.

3. A medical connector with a tube according to claim 1 or 2, wherein the tip of the outer surface of the tube is in contact with the conical portion.

4. A medical connector with a tube according to any one of claims 1 to 3, wherein an adhesive is applied between the tube and the inner circumferential surface of the through hole.

5. The aforementioned adhesive is a UV adhesive, as described in claim 4 for the tube-attached medical connector.

6. A medical connector with a tube according to any one of claims 1 to 5, wherein the taper angle of the tapered surface constituting the conical portion is 20 degrees or more and 60 degrees or less.

7. The medical connector with a tube according to any one of claims 1 to 6, wherein the inner circumferential surface of the through hole further comprises a guide portion adjacent to the cylindrical portion on the side opposite to the connecting portion and having an inner diameter that increases toward the tip of the base portion.

8. The cylindrical portion is longer than the conical portion. A medical connector with a tube according to any one of claims 1 to 7.

9. The medical connector with a tube according to any one of claims 1 to 8, wherein the outer diameter of the tube is 3 mm or less.

10. A medical connector with a tube according to any one of claims 1 to 9, wherein the entire connector is integrally molded as a single part.

11. The aforementioned connection part is A hollow cylindrical tubular section, A female taper surface is provided on the inner circumferential surface of the tubular portion, the inner diameter of which increases towards the tip of the tubular portion, A medical connector with a tube according to any one of claims 1 to 10, further comprising a screw projection provided on the outer circumferential surface of the tubular portion.

Images