JP4590515B2 - Connection structure between drip tube and flexible tube, connection method thereof, and tube welding jig of ultrasonic welding machine used therefor - Google Patents

Description

The present invention relates to a connection structure between a drip tube and a flexible tube, a connection method thereof, and a tube welding jig of an ultrasonic welding machine used therefor.

In an infusion set, a blood transfusion set, and the like, a flexible tube is connected to a drip tube and used. The following connection structures are known. That is, the tube connection portion of the drip tube is provided with an outer tube and an inner tube disposed in the axial direction in the outer tube, and an annular insertion gap is formed between the outer tube and the inner tube. Is inserted into the end of the tube, and the end of the tube is inserted into the insertion gap .

  By the way, polyvinyl chloride has been conventionally used as a material for the drip tube. However, if the infusion tube made of polyvinyl chloride is discarded and then incinerated, dioxins may be generated depending on the incineration method.

  Therefore, the material of the drip tube is being switched to a material that hardly generates dioxins such as polypropylene. However, many materials that do not easily generate dioxins have low frictional resistance with the tube. For this reason, when such a material is used for an infusion tube, the tube may fall out of the infusion tube when the tube connected to the infusion tube is pulled strongly.

In order to improve this, it is also conceivable to use an adhesive or insert a caulking member between the outer tube and the tube. However, a third material other than drip chamber and tubing, the use of members, since the lead to complication of the cost increase and connecting work, which is not preferable.

  In order to solve the above problem, a soldering iron-like heating means is pressed against a part of the outer surface of the outer tube to form a concave melting portion, and the radially inner portion of the melting portion in the outer tube Is deformed radially inward to form a protrusion protruding radially inward on the inner peripheral portion of the outer tube, and the protrusion is pressed against the outer surface of the tube to press the tube against the inner tube. There has been proposed an improvement in the connection strength between a tube and a drip tube (for example, see Patent Document 1).

  However, in the above-mentioned conventional one, a soldering iron-like heating means is pressed against the outer surface of the outer tube, the outer tube is pressed and deformed, and the protrusion is formed indirectly from the outside of the outer tube. It is difficult to form a projection well and press it against the outer surface of the tube with a large pressure.Therefore, it is difficult to increase the pressing force of the projection on the inner tube of the tube, and the connection strength between the drip tube and the tube is increased. The reality is that it was difficult to do. Further, since a concave melting portion is formed on the outer surface of the tube, there is a problem that the appearance appearance of the connection portion of the tube with the drip tube is poor.

JP 2000-354635 A

  The problem to be solved is that when the drip tube is made of a material that hardly generates dioxins such as polypropylene, the connection strength between the tube and the drip tube cannot be increased.

An object of the present invention is to provide a connection structure between a drip tube and a flexible tube , which solves the above-mentioned problems, a connection method thereof, and a tube welding jig of an ultrasonic welding machine used therefor, and achieves the object. Therefore, the feature of the connection structure of the drip tube and the flexible tube of the present invention is that the connected member of the drip tube to which the substantially uniform-thickness flexible tube is connected is connected to the outer tube and the outer tube. An inner tube arranged axially in the tube is provided, an annular insertion gap is formed between the outer tube and the inner tube, the inner tube is press-fitted into the end of the flexible tube, and flexible Ring-shaped guide body that suppresses deformation of the outer tube radially outward in the outer tube in which the end of the tube is inserted into the insertion gap and the flexible tube is connected to the connected member together with externally fitted, between the outer tube flexible tube, the outer tube and the axial direction at the tip portion Insert the tube welding jig having a contact portion that contacts with respect to the radial direction, the leading end of the contact portion with respect to the axial direction intermediate portion of the ring-shaped guide body, through the outer tube, overlap allowed, by melt means, through a tube welding jig, only the inner peripheral portion of the outer tube is melted, by solidifying the pressure contact shape in the radial direction against the flexible tube, the inner peripheral portion of the outer tube In addition, a detachment preventing portion that presses the flexible tube against the inner tube is formed.
Further, the separation preventing part may be formed in an arc shape that is continuous in the circumferential direction.
In addition, a separation preventing portion may be formed on the outer tube over the entire circumference.
Furthermore, a plurality of separation preventing portions may be formed in the outer tube at equal intervals in the circumferential direction.
Further, the separation preventing part may be formed only in a part of the outer tube in the circumferential direction.
Furthermore, the outer tube may be formed from a material that can be melted by an ultrasonic welder.
In addition, the connected member may be an infusion set drip tube, and the flexible tube may be an infusion set tube.
Further, the medical device connection method of the present invention is characterized in that the drip tube and the flexible tube are connected, and the inner tube is press-fitted into the end of the flexible tube and is flexible. insert the end of sex tube insertion gap, to the outer tube, both the deformation suppressing ring guide body radially outward of the outer tube externally fitted, between the outer tube flexible tube, A tube welding jig having an abutting portion that abuts the outer tube with respect to the axial center direction is inserted into the distal end portion. through the outer tube, thereby to overlap, by melting means, that via the tube welding jig, only the inner peripheral portion of the outer tube is melted and solidified in pressure contact shape in the radial direction against the flexible tube in the inner peripheral portion of the outer tube to form a detachment preventing portion, this coming-off preventing portion, the flexible It lies in that presses the inner tube a cube.
Note that the melting means may be an ultrasonic welder.
Further, when the feature of the tube welding jig ultrasonic welding machine of the present invention, tip, tip open, both are fitted on the flexible tube, between the outer tube flexible tube The distal end portion of the outer fitting portion is in contact with the outer tube in the axial direction to melt the outer tube.
In addition, in the outer peripheral part of the outer fitting part, an fitting / removing opening part for fitting / removing the flexible tube from the radial direction may be formed over the entire length in the axial direction.
Further, an insertion hole through which the flexible tube is inserted may be formed on the outer peripheral portion of the outer fitting portion.

According to the present invention, only the inner peripheral portion of the outer tube is melted and solidified in a pressure-contact manner on the tube, and the detachment is pressed against the tube so as to form a detachment preventing portion that presses the tube against the inner tube. The prevention part is formed directly from the outside of the outer tube, not indirectly, so the separation prevention part can be easily and well formed and can be pressed against the outer surface of the tube with a large pressure. The pressing force to the inner pipe can be increased. Thereby, even when the member to be connected is manufactured from a material that hardly generates dioxins such as polypropylene, the connection strength between the member to be connected and the tube can be increased.
In addition, since the guide body suppresses deformation of the outer tube in the radially outward direction, the melt that forms the separation preventing portion can be prevented from flowing radially outward when the separation preventing portion is formed. Therefore, the separation preventing portion can be pressed against the outer surface of the tube with a large pressure. Thereby, the pressing force to the inner tube of the tube by the separation preventing portion can be further increased, and the connection strength between the connected member and the tube can be increased.
Further, for example, it is not necessary to form a dent or the like on the outer peripheral surface of the outer tube by the heating means, and the outer peripheral surface is not deformed, so that the appearance appearance of the connecting portion between the drip tube and the tube can be improved.
Furthermore, since the separation preventing part is formed in the outer tube, the constituent material of the tube connected to the connected member is not limited.
In addition, no adhesive or caulking member inserted between the outer tube and the tube is used, and the use of a third material or member other than the member to be connected and the tube increases the cost and makes the connection work complicated. There is no possibility of inviting it .
According to the invention of claim 10 , when forming the separation preventing portion, the melt forming the separation preventing portion can be suppressed from flowing to the contact portion side of the tube welding jig with respect to the axial direction. The separation prevention part can be pressed against the outer surface of the tube with a large pressure. Thereby, the pressing force to the inner tube of the tube by the separation preventing portion can be further increased, and the connection strength between the connected member and the tube can be increased.
According to invention of Claim 11 and 12 , a tube can be fitted to the external fitting part of a tube welding jig in the state connected to the to-be-connected member.

The present invention relates to a connection structure between a drip tube and a flexible tube , which can increase the connection strength between the tube and the drip tube, even when the drip tube is made of a material that does not easily generate dioxins such as polypropylene. A tube welding jig for an ultrasonic welder used in the present invention is provided.

  Hereinafter, Example 1 in which the present invention is applied to an infusion set and a transfusion set will be described with reference to FIGS. 1 shows the main part of Example 1, but for convenience of explanation, the main part is shown in an upside down state when the infusion set or the blood transfusion set is used. As shown in FIGS. 1 and 2, the set includes a drip tube 1 exemplified as a connected member and a flexible tube 2 connected to the drip tube 1.

  The drip tube 1 has a hollow main body 4 that mainly constitutes the drip tube 1, and an outer tube (outer tube) 5 and an inner tube (inner tube) 6 that protrude integrally downward from the lower end of the main body 4. In addition, as described above, there is a case where it does not project integrally. The main body 4 stores liquids such as physiological saline and various chemical solutions, for example. The outer tube 5 and the inner tube 6 are formed into a tube (cylinder) shape having a vertical axis, and the inner tube 6 is concentrically arranged in the axial direction in the outer tube 5 to form a double inner tube ( Cylinder). An annular insertion gap 7 is formed between the outer tube 5 and the inner tube 6, and this gap 7 opens to the outside at the tip of the outer tube 5. The protruding amount of the outer tube 5 from the main body 4 is considerably smaller than that of the inner tube 6, and the inner tube 6 protrudes greatly from the outer tube 5 to the outside.

  The inner peripheral surface of the outer tube 5 is stepped, and includes a small-diameter portion 8 on the base side, a large-diameter portion 9 on the distal end side that has a larger diameter than the small-diameter portion 8, and a small-diameter portion 8 and a large-diameter portion 9. And a stepped surface 10 in the middle of the axial center that has a planar shape in front of the axial center. In addition, although the small diameter part 8 and the large diameter part 9 are made into the substantially constant diameter regarding the axial center direction, they may be slightly tapered toward the base end part. On the inner peripheral surface of the outer tube 5, axial longitudinal ribs 11 projecting radially inward are disposed at equal intervals in the circumferential direction, and the cross-sectional shape of the longitudinal ribs 11 is triangular. In some cases, the vertical ribs 11 are not provided.

  The inner tube 6 communicates with the inside of the main body 4, and the outer diameter of the inner tube 6 is larger than the inner diameter of the tube 2, but the outer peripheral surface of the distal end portion of the inner tube 6 is chamfered, and the inner tube 6 Is easily inserted (press-fitted) into the end of the tube 2.

  The constituent material of the drip tube 1 is not particularly limited, but the outer tube 5 needs to be formed of a material that can be melted by the following melting means. Examples of the constituent material of the drip tube 1 include polyolefins such as polyethylene and polypropylene, ethylene-vinyl acetate copolymer (EVA), polyvinyl chloride, polystyrene, polyamide, polyimide, polycarbonate, and poly- (4-methylpentene-1). ), Acrylic resin, polymethyl methacrylate, acrylonitrile-butadiene-styrene copolymer (ABS resin), acrylonitrile-styrene copolymer (AS resin), butadiene-styrene copolymer, polyethylene terephthalate (PET), polybutylene terephthalate Polyester such as (PBT), polyether, polyether ketone (PEK), polyether ether ketone (PEEK), polyacetal (POM), polyphenylene oxide, polysulfone, polyether Rufon, polyphenylene sulfide, polyarylate, aromatic polyester (liquid crystal polymer), polytetrafluoroethylene, polyvinylidene fluoride, other fluorine-based resins, epoxy resins, silicone resins, and various polymer materials such as polyurethane. Of the above, polyolefins such as polyethylene and polypropylene, that is, non-chlorine materials are preferably used because dioxins are hardly generated when the infusion tube 1 is incinerated.

  In the end of the tube 2, substantially the entire inner tube 6 is inserted. At the time of this insertion, the inner tube 6 pushes and spreads the tube 2 radially outward while being elastically deformed. 2 is in close contact, and the inner tube 6 and the tube 2 are connected in a liquid-tight state. At the time of this connection, the end of the tube 2 is inserted into the insertion gap 7 between the outer tube 5 and the inner tube 6. In this inserted state, the small diameter portion 8 between the inner peripheral surface of the outer tube 5 and the tube 2 is inserted. There is a gap, so that the tube 2 can be easily connected to the main body 4.

  The constituent material of the tube 2 is not specifically limited, For example, resin materials, such as polyolefin, such as polyethylene and a polypropylene, soft polyvinyl chloride, ethylene-vinyl acetate copolymer (EVA), polyamide, natural rubber, silicone rubber, Examples thereof include various rubber materials such as styrene-butadiene rubber and elastic materials such as various thermoplastic elastomers. Of these, non-chlorine materials such as polyolefin are preferred for the same reason as in the case of the drip tube 1.

  By the way, in order to increase the connection strength between the drip tube 1 and the tube 2, a part of the outer tube 5 of the drip tube 1 is melted by the following melting means as described below, and this melt is put into the tube 2. Solidified in a pressure contact shape on the radially outer side (directly, not indirectly), as shown in FIG. 3, a separation preventing portion (detachment preventing portion) 13 is formed on the inner peripheral portion of the outer tube 5, The tube 2 is pressed against the inner tube 6 by the separation preventing portion 13.

  As the melting means, an ultrasonic welding machine is used, and this ultrasonic welding machine is provided with a tube welding jig 15 and a ring-shaped guide body 16 as shown in FIGS.

The base portion of the tube welding jig 15 is a screwed portion 17 that is detachably screwed to the ultrasonic welder main body side, and the distal end portion of the tube welding jig 15 is a cylindrical outer shape that is detachably fitted to the tube 2. The fitting portion 18 is provided. In the outer fitting portion 18, an fitting / removing opening 19 for fitting the tube 2 to the outer peripheral portion of the outer fitting portion 18 from the radial direction is formed over the entire length in the axial direction. 5 is a processing hole for making the outer fitting portion 18 hollow. The front end portion of the outer fitting portion 18 is a contact portion 20 having a smaller diameter than other portions. The contact portion 20 is inserted into the small diameter portion 8 of the outer tube 5 and is in contact with the stepped surface 10 with respect to the axial direction, and the outer diameter thereof is larger than the inner diameter of the small diameter portion 8 of the outer tube 5. The contact portion 20, that is, the inner diameter of the outer fitting portion 18 is slightly larger than the outer diameter of the tube 2 into which the inner tube 6 is press-fitted. Yes.

  The guide body 16 is fitted over substantially the entire outer tube 5 from the lateral direction (outward in the radial direction), and its inner peripheral surface faces the outer peripheral surface of the outer tube 5 via a small gap, or (substantially) By abutting over the entire circumference, deformation and expansion of the outer tube 5 outward in the radial direction are suppressed (restricted). The guide body 16 is divided in the circumferential direction and has, for example, a pair of semicircular segments 21.

  When the separation preventing portion 13 is formed in the outer tube 5 by the ultrasonic welding machine, the inner tube 6 of the drip tube 1 is press-fitted into the end portion of the tube 2, and the end portion of the tube 2 is inserted into the inner tube 5 and the inner tube 5. The tube 2 and the drip tube 1 are connected by inserting into the insertion gap 7 between the tubes 6.

  Next, as shown in FIGS. 1 and 2, the end of the tube 2 on the drip tube side is fitted to the outer fitting portion 18 of the tube welding jig 15 via the fitting opening 19. . As described above, since the fitting opening 19 is formed in the outer fitting portion 18, the tube 2 can be fitted to the outer fitting portion 18 in a state where the tube 2 is connected to the drip tube 1.

  Next, a pair of semicircular segments 21 of the guide body 16 are fitted over substantially the entire outer tube 5 from the lateral direction, and the inner peripheral surface of the guide body 16 is inserted into the outer peripheral surface of the outer tube 5 via a small gap. Facing each other or (substantially) abutting over the entire circumference.

Next, as shown in FIG. 3, the contact portion 20 of the tube welding jig 15 is inserted into the insertion gap 7, and the contact portion 20 is contacted with the stepped surface 10 of the outer tube 5 in the axial direction. With respect to the radial direction, the tip of the contact portion 20 is overlapped with the middle portion in the axial center direction of the guide body 16 via the outer tube 5. Thereafter, the ultrasonic welding machine is operated to cause the tube welding jig 15 to oscillate longitudinally, that is, in the axial direction. Thus, the tube 2 itself is not melted by the contact portion 20, and the lower portion (axial direction) of the stepped surface 10 of the outer tube 5 and the lower portion (front side in the axial direction) of the stepped surface 10. a portion located forward), that is, only the inner peripheral portion of the portion of the outer tube 5 is melted and solidified in pressure contact shape in the radial direction against the tube 2, disengagement prevention part 13 is formed, escape prevention part 13 As a result, the tube 2 is pressed against the inner tube 6.

  In FIG. 2, the cross-hatched portion shows the melted and solidified portion of the outer tube 5, that is, the separation preventing portion 13, and the plan view shape of the separation preventing portion 13 is the bottom view of the contact portion 20. It is made into the substantially semicircle shape substantially corresponding to a shape, and is continuing in the circumferential direction. Note that the detachment preventing portion 13 may not be formed in an arc shape as described above but may be formed in a very small part in the circumferential direction of the outer tube 5.

  In the above case, even if the longitudinal ribs 11 are present on the inner peripheral surface of the outer tube 5, the portion of the longitudinal ribs 11 located below the contact portion 20 is melted, so there is no problem. The oscillation time of the ultrasonic welder is preferably 0.2 seconds to 1 second.

As described above, by melting a part including the inner circumferential portion of the outer tube 5, in Rukoto solidified into pressure contact shape to the tube 2, the inner peripheral portion of the outer tube 5, directly, forming a detachment preventing portion 13 Since the separation preventing portion 13 is not indirectly formed from the outside of the outer tube 5, the separation preventing portion 13 can be easily and satisfactorily formed and can be pressed against the outer surface of the tube 2 with a large pressure, thereby preventing the separation. The pressing force of the portion 13 on the inner tube 6 of the tube 2 can be increased. Thereby, even when the drip tube 1 is made of a material that hardly generates dioxins such as polypropylene, the connection strength between the drip tube 1 and the tube 2 can be increased.

  Further, the abutment portion 20 of the tube welding jig 15 presses the separation preventing portion 13 from the axial center direction, and the guide body 16 suppresses deformation and expansion of the outer tube 5 outward in the radial direction. Therefore, at the time of forming the separation preventing portion 13, the melt forming the separation preventing portion 13 can be prevented from flowing toward the contact portion 20 side or radially outward with respect to the axial direction. The separation preventing part 13 can be pressed against the outer surface of the tube 2 with a large pressure. Thereby, the pressing force to the inner tube 6 of the tube 2 by the separation preventing unit 13 can be further increased, and the connection strength between the drip tube 1 and the tube 2 can be increased.

  Further, for example, there is no need to form a dent or the like on the outer peripheral surface of the outer tube 5 by heating means, and the outer peripheral surface is not deformed, so that the appearance appearance of the connecting portion between the drip tube 1 and the tube 2 can be improved.

  Moreover, since the detachment preventing portion 13 is formed in the outer tube 5, the constituent material of the tube 2 connected to the drip tube 1 is not limited. Furthermore, no adhesive or caulking member inserted between the outer tube 5 and the tube 2 is used, and the use of a third material or member other than the drip tube 1 or the tube 2 increases the cost or connection. There is no risk of complicating work.

  After the detachment preventing portion 13 is formed on the outer tube 5 as described above, each segment 21 of the guide body 16 is removed from the outer tube 5, and the tube welding jig 15 is inserted into the outer tube 5 and the inner tube 6. It is made to detach | leave from the clearance gap 7 to an axial direction. Next, the tube welding jig 15 is moved in the lateral direction, and the tube 2 is detached from the external fitting portion 18 of the tube welding jig 15 through the fitting opening 19.

  7 to 9 show a second embodiment of the present invention, in which no stepped surface is formed on the inner peripheral surface of the outer tube 5, and the inner diameter is substantially constant with respect to the axial direction. On the other hand, it may be slightly tapered.

According to this embodiment, when the separation preventing portion 13 is formed on the outer tube 5 by the ultrasonic welding machine, the contact portion 20 of the tube welding jig 15 is brought into contact with the distal end portion of the outer tube 5. Thereafter, the ultrasonic welding machine is operated to cause the tube welding jig to oscillate longitudinally, that is, in the axial direction. Accordingly, the tube 2 itself is not melted by the contact portion 20 in the same manner as in the first embodiment, and the portion of the outer tube 5 positioned below the contact portion 20 is melted, solidified, and detached. The prevention part 13 is formed.
In FIG. 8, only the portion of the outer tube 5 positioned below the contact portion 20, that is, the inner peripheral portion is melted and solidified, but the outer peripheral portion at the distal end portion of the outer tube 5. In some cases, the entire structure including the melt may be melted and solidified.

  10 to 12 show a third embodiment of the present invention. In the outer periphery of the outer fitting portion 18 of the tube welding jig 15, no fitting opening is formed. Instead, the tube 2 An insertion hole 23 is formed for inserting the.

  According to this embodiment, when the tube 2 is fitted to the outer fitting portion 18 of the tube welding jig 15, the tube 2 is inserted from the distal end opening of the tube welding jig 15 to weld the tube. It passes through the insertion hole 23 of the jig 15. Thereby, in a state where the tube 2 is connected to the drip tube 1, the tube 2 can be fitted to the outer fitting portion 18 of the tube welding jig 15. In addition, after the detachment preventing portion 13 is formed on the outer tube 5, the tube 2 can be easily detached from the outer fitting portion 18 of the tube welding jig 15 by pulling the drip tube 1 below the tube welding jig 15. it can.

  FIGS. 13 to 16 show Examples 4 to 7 of the present invention. In Example 4 shown in FIG. 13, the contact portion 20 of the tube welding jig 15 is made into a complete cylindrical shape. A separation preventing portion is formed on the outer tube 5 over the entire circumference. In Example 5 shown in FIG. 14 and Example 6 shown in FIG. 15, a plurality of contact portions 20 are arranged at equal intervals in the circumferential direction, whereby a plurality of separation preventing portions are arranged in the outer tube 5 in the circumferential direction. It is formed at equal intervals. In Example 7 shown in FIG. 16, the contact part 20 is arrange | positioned only at one place of the circumferential direction, and, thereby, a single detachment preventing part is formed only at one place of the outer pipe 5 in the circumferential direction. .

In addition, although an Example applies the present invention to an infusion set, a connection structure of a drip tube of a blood transfusion set, and a flexible tube, a connection method, and a tube welding jig of an ultrasonic welding machine used therefor, The present invention can also be applied to other drip tube and flexible tube connection structures, connection methods, and tube welding jigs of ultrasonic welders used therefor.

[Test example]
Next, the present invention will be further described with reference to a test example in which the present invention is implemented and a conventional example, but the present invention is not limited to the test example.

  First, in Test Examples 1 and 2, the infusion set drip tube and the tube having the structure of Example 1 were used, and the drip tube and the connection tube were connected in the same manner as in Example 1, and the outer tube was connected by an ultrasonic welding machine. The stepped surface and the lower portion of the stepped surface and the portion located below the contact portion were melted and solidified to form a separation-preventing portion having a substantially semicircular shape in plan view continuous in the circumferential direction.

  The pressure during operation of the ultrasonic welder is 0.2 MPa in Test Examples 1 and 2, and the melting time (ultrasonic oscillation time) is 0.2 seconds in Test Example 1. In Test Example 2, it was 0.4 seconds. In the conventional example, as in the test example, the drip tube and the tube were connected, but the separation preventing portion was not formed by the ultrasonic welding machine.

  Next, a tensile test is performed on each of the connected drip tubes and tubes addressed to the five sets in each of the above test examples and the conventional example, and when the tube comes out of the drip tube or the tube is cut. Tensile force was measured, and five measured values were obtained for each of the test examples and the conventional example. The test results are shown in Table 1 below.

  In Table 1, the average tensile force is the average value of the five measured values obtained in each test example and the conventional example, and the maximum tensile force is the maximum value among the above five measured values. The minimum tensile force is the minimum value among the above five measured values. In the remarks, it shows how many sets the tube has been pulled or cut in the tensile test for 5 sets of connected drip cylinders and tubes. For example, in the remarks column of Test Example 1, “5 “Two sets out of the set, the tube is pulled out from the drip tube” means that two sets out of the five sets are pulled out of the drip tube, and in the remaining sets, the tube is cut.

  As can be seen from Table 1, in all the test examples, the average tensile force, the maximum tensile force, and the minimum tensile force are larger than those in the conventional example, and the test example in which the present invention is implemented is superior to the conventional example. I understand. It can also be seen that the longer the melting time, the larger the average tensile force, maximum tensile force and minimum tensile force.

It is a longitudinal cross-sectional view which shows Example 1 of this invention. It is AA arrow sectional drawing of FIG. FIG. 2 is an operational state diagram of FIG. 1. It is a perspective view of the tube welding jig | tool of FIG. FIG. 5 is a front view of FIG. 4. FIG. 5 is a bottom view of FIG. 4. It is a longitudinal cross-sectional view which shows Example 2 of this invention. FIG. 8 is a cross-sectional view taken along line B-B in FIG. 7. FIG. 8 is an operational state diagram of FIG. 7. It is a perspective view of the tube welding jig | tool which shows Example 3 of this invention. It is a front view of FIG. It is a bottom view of FIG. It is a cross-sectional view showing Example 4 of the present invention. It is a cross-sectional view showing Example 5 of the present invention. It is a cross-sectional view showing Example 6 of the present invention. It is a cross-sectional view showing Example 7 of the present invention.

Explanation of symbols

1 Infusion tube (member to be connected)
2 Tube 4 Body 5 Outer tube 6 Inner tube 7 Insertion gap 13 Detachment prevention part 15 Tube welding jig 16 Guide body 18 Outer fitting part 19 Fitting opening part 20 Contact part 23 Insertion hole

Claims (12)

The connected member of the drip tube to which the flexible tube having a substantially uniform wall thickness is connected is provided with an outer tube and an inner tube arranged in the axial direction in the outer tube,
An annular insertion gap is formed between the outer tube and the inner tube,
The inner tube is press fit into the end of the flexible tube;
The end of the flexible tube is inserted into the insertion gap,
In the case where the flexible tube is connected to the connected member,
A ring-shaped guide body that suppresses deformation of the outer tube in the radially outward direction is externally fitted to the outer tube, and between the outer tube and the flexible tube, the tip is in contact with the outer tube in the axial direction. A tube welding jig having a contact portion is inserted, and with respect to the radial direction, the tip of the contact portion is overlapped with an intermediate portion in the axial direction of the ring-shaped guide body via an outer tube, , through a tube welding jig, only the inner peripheral portion of the outer tube is melted, by solidifying the pressure contact shape in the radial direction against the flexible tube,
Connection structure between a drip tube and a flexible tube in which a separation preventing part for pressing the flexible tube against the inner tube is formed on the inner periphery of the outer tube The connection structure of a drip tube and a flexible tube according to claim 1, wherein the separation preventing portion is formed in an arc shape continuous in the circumferential direction. 2. The connection structure between a drip tube and a flexible tube according to claim 1, wherein a separation preventing portion is formed on the outer tube over the entire circumference. The connection structure between a drip tube and a flexible tube according to claim 1, wherein a plurality of separation preventing portions are formed in the outer tube at equal intervals in the circumferential direction. 2. The connection structure between a drip tube and a flexible tube according to claim 1, wherein a separation preventing portion is formed only in a part in the circumferential direction of the outer tube. The connection structure of the drip tube and the flexible tube according to any one of claims 1 to 5, wherein the outer tube is formed of a material that can be melted by an ultrasonic welder. The connection structure of the drip tube and the flexible tube according to any one of claims 1 to 6, wherein the connected member is an infusion set drip tube, and the flexible tube is an infusion set tube. A method of connecting the drip tube according to any one of claims 1 to 7 and a flexible tube ,
With the inner tube is press-fitted into the end of the flexible tube is inserted into an end of the flexible tube insertion gap,
A ring-shaped guide body that suppresses deformation of the outer tube in the radially outward direction is fitted on the outer tube, and the outer tube and the flexible tube are in contact with the outer tube with respect to the axial direction in the axial direction. Insert a tube welding jig having a contact portion, and with respect to the radial direction, the tip of the contact portion is overlapped with an intermediate portion in the axial direction of the ring-shaped guide body via an outer tube,
The melting means, through a tube welding jig, only the inner peripheral portion of the outer tube is melted, by solidifying the pressure contact shape in the radial direction against the flexible tube,
A separation prevention part is formed on the inner periphery of the outer tube,
A method of connecting the drip tube and the flexible tube , which presses the flexible tube against the inner tube by the separation preventing portion. The method for connecting a drip tube and a flexible tube according to claim 8, wherein the melting means is an ultrasonic welder. A tube welding jig of the ultrasonic welder according to claim 9,
Tip, the tip is open, both are fitted on the flexible tube, is a cylindrical outer fitting portion which is inserted between the outer tube flexible tube,
A tube welding jig for an ultrasonic welding machine in which a distal end portion of the outer fitting portion is in contact with the outer tube in the axial direction to melt the outer tube. The tube welding of the ultrasonic welding machine according to claim 10, wherein an opening for fitting / removal for fitting / removing the flexible tube from the radial direction is formed in the outer peripheral portion of the outer fitting portion over the entire length in the axial direction. Jig. The tube welding jig of the ultrasonic welding machine according to claim 10, wherein an insertion hole through which the flexible tube is inserted is formed on an outer peripheral portion of the outer fitting portion.

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