Coupling unit and method for assembling the same

Abstract

To easily perform a work for inserting a projection portion into a liquid feeding channel without visually confirming the liquid feeding channel formed on a resin tube, by a worker.SOLUTION: A joint structure 100 includes: a main body portion 110; a cylindrical portion 120 cylindrically formed to project from the main body portion 110 along an axis X and holding an outer peripheral surface of a resin tube 200; and a projection portion 130 formed into a shaft shape to project from the main body portion 110 along the axis X and forming an insertion groove 133 to insert the resin tube 200 between the projection portion and the cylindrical portion 120. The main body portion 110 and the projection portion 130 are provided with a connection flow channel 100a extended along the axis X and connecting a liquid feeding channel 210 with the other flow channel, and a tip of the projection portion 130 is located on a position close to the main body portion 110 with respect to a tip of the cylindrical portion 120.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention , continued The present invention relates to an assembly method for a hand unit and a joint unit. [Background technology]

[0002] Conventionally, there is known a tube pump (peristaltic pump) equipped with a pair of roller parts that rotate around an axis while in contact with a tube through which liquid flows (see, for example, Patent Document 1). The tube pump disclosed in Patent Document 1 rotates the pair of roller parts in the same direction around the axis, thereby discharging liquid flowing into the tube from the inlet side to the outlet side. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-67054 A Summary of the Invention [Problem to be solved by the invention]

[0004] The tube used in the tube pump is required to be durable against the pressing force from the pair of rollers, because the pair of rollers repeatedly come into contact with each other. Therefore, the thickness of the tube (half the difference between the outer diameter and the inner diameter of the tube) must be set to a thickness sufficient to obtain the desired durability. The tube is made of, for example, a flexible resin material, and the rigidity of a tube with a sufficient thickness is relatively high.

[0005] Furthermore, for example, in applications such as cell culture for regenerative medicine, there are cases where the flow rate of culture fluid or the like transported by a tube pump per unit time is required to be extremely small (for example, about 0.01 ml / min to 1 ml / min). Tubes used for such applications have extremely small inner diameters of flow paths (for example, 0.30 mm). Furthermore, when a tube used in a tube pump is to be connected to another flow path, a joint structure is required that includes a joint portion that is partially inserted into the flow path of the tube in order to connect them.

[0006] However, when the inner diameter of the flow path is small compared to the thickness of the tube, it is difficult to elastically deform the flow path of the tube, which has high rigidity, to insert the joint part, and especially when the inner diameter of the flow path is extremely small, it is difficult to insert the joint part while visually checking the flow path.

[0007] The present invention has been made in consideration of the above circumstances, and provides a joint structure that enables an operator to easily insert a protrusion into a liquid supply flow path formed in a resin tube without visually checking the liquid supply flow path formed in the resin tube. Equipped An object of the present invention is to provide a joint unit and a method for assembling the joint unit. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention employs the following means. A joint according to one aspect of the present invention unit A resin tube is formed with a liquid supply flow path extending along an axis and has a circular cross section perpendicular to the axis. and the resin tube. A joint structure attached to the end of and the joint structure comprises:a cylindrical portion formed in a cylindrical shape so as to protrude from the main body portion along the axis and which holds the outer peripheral surface of the resin tube; and a protrusion formed in an axial shape so as to protrude from the main body portion along the axis and which forms an insertion groove between the cylindrical portion and into which the resin tube is inserted, the main body portion and the protrusion having a connecting flow path which extends along the axis and connects the liquid supply flow path to another flow path, the tip of the protrusion being positioned at a position closer to the main body portion than the tip of the cylindrical portion, the protrusion having a base which extends along the axis from a bottom of the insertion groove and has a constant outer diameter, and a tip portion whose outer diameter gradually decreases from the base to the tip, and in a non-inserted state in which the protrusion is not inserted into the liquid supply flow path of the resin tube, the outer diameter of the base is larger than the inner diameter of the liquid supply flow path, and a seal area is formed between the resin tube which has been elastically deformed by the protrusion being inserted into the liquid supply flow path and the base.

[0009] A joint according to one aspect of the present invention unit According to The joint structure is The resin tube is inserted into a protrusion that forms an insertion groove between the protrusion and a cylindrical portion that holds the outer circumferential surface of the resin tube, and the tip of the protrusion is located closer to the main body than the tip of the cylindrical portion. Therefore, when the end of the resin tube is brought closer to the joint structure, the outer circumferential surface of the resin tube is held by the inner circumferential surface of the cylindrical portion before the end of the resin tube comes into contact with the tip of the protrusion. By holding the outer circumferential surface of the resin tube on the inner circumferential surface of the cylindrical portion, a liquid delivery flow path formed in the resin tube is positioned on the same axis as the central axis of the cylindrical portion.

[0010] Since the protrusion is disposed on the same axis as the central axis of the cylindrical portion, the fluid delivery flow path formed in the resin tube and the protrusion are disposed on the same axis. When the worker presses the resin tube toward the main body of the joint structure in this state, the protrusion disposed on the same axis is inserted into the fluid delivery flow path. In this way, the worker can easily insert the protrusion into the fluid delivery flow path without visually checking the fluid delivery flow path formed in the resin tube.

[0011] A joint according to one aspect of the present invention unit In the present invention, it is preferable that the length of the protrusion along the axis is three times or more the outer diameter of the protrusion. When the length of the protrusion along the axis is three times or more the outer diameter of the protrusion, the protrusion becomes needle-shaped and protrudes from the main body. By inserting the needle-shaped protrusion into the liquid-transport flow path of the resin tube, a seal area of ​​sufficient length can be provided between the outer circumferential surface of the protrusion and the liquid-transport flow path. In addition, it is a difficult task for an operator to insert the needle-shaped protrusion into the liquid-transport flow path while visually checking it, but since the protrusion is inserted into the liquid-transport flow path with the liquid-transport flow path and the protrusion arranged on the same axis, the operator can easily insert the protrusion into the liquid-transport flow path.

[0012] A joint according to one aspect of the present invention unit In the present invention, it is preferable that the length from the tip of the protrusion to the tip of the cylindrical portion is 0.2 times or more the inner diameter of the cylindrical portion. Since the length from the tip of the protrusion to the tip of the tubular portion is 0.2 times or more the inner diameter of the tubular portion, the end of the resin tube comes into contact with the tip of the protrusion when the end of the resin tube is inserted a sufficient length into the inner diameter of the tubular portion, so that the protrusion can be inserted into the liquid delivery flow path while the outer circumferential surface of the resin tube is securely held by the inner circumferential surface of the tubular portion.

[0013] A fitting unit according to one aspect of the present invention comprises any of the fitting structures described above and the resin tube, wherein the outer diameter of the protrusion is larger than the inner diameter of the liquid delivery flow path, and the outer diameter of the resin tube is smaller than the inner diameter of the tubular portion. Since the outer diameter of the protrusion is larger than the inner diameter of the liquid delivery flow path, when the protrusion is inserted into the liquid delivery flow path, the protrusion elastically deforms so that the inner diameter of the liquid delivery flow path expands to the size of the outer diameter of the protrusion. The resin tube forms a seal area between itself and the outer peripheral surface of the protrusion due to the contraction force caused by the elastic deformation. In addition, since the outer diameter of the resin tube is smaller than the inner diameter of the cylindrical portion, it is possible to insert the resin tube into the insertion groove even if the outer diameter of the resin tube expands as the inner diameter of the liquid delivery flow path expands.

[0014] In the joint unit according to one aspect of the present invention, the outer diameter of the resin tube is preferably 3 times or more and 15 times or less than the inner diameter of the resin tube. Since the outer diameter of the resin tube is sufficiently large compared to the inner diameter, the resin tube has a sufficient thickness. Therefore, even when durability against pressing force is required, such as when used in a tube pump, the resin tube can exhibit sufficient rigidity and the associated durability. Furthermore, when a resin tube with high rigidity is used, it is difficult to insert a protrusion and cause elastic deformation, but since it is possible to insert the protrusion into the liquid delivery flow path while the outer peripheral surface of the resin tube is held by the inner peripheral surface of the cylindrical portion, the protrusion can be easily inserted into the resin tube.

[0015] In the joint unit according to one aspect of the present invention, the resin tube preferably has an inner diameter of not less than 0.1 mm and not more than 1.0 mm. Since the inner diameter of the resin tube is extremely small, 0.1 mm or more and 1.0 mm or less, the flow rate of the liquid flowing through the flow path formed in the resin tube per unit time can be kept small. Furthermore, even if the inner diameter of the resin tube is extremely small, 0.1 mm or more and 1.0 mm or less, the work of inserting the protrusion into the flow path for liquid delivery formed in the resin tube can be easily performed without visually checking the flow path for liquid delivery formed in the resin tube.

[0016] A method for assembling a fitting unit according to one aspect of the present invention is a method for assembling a fitting unit including a resin tube having a liquid supply flow path extending along an axis and having a circular cross section perpendicular to the axis, and a fitting structure attached to an end of the resin tube, the fitting structure including a main body, a tubular portion formed in a cylindrical shape so as to protrude from the main body along the axis and holding an outer circumferential surface of the resin tube, and a protrusion formed in an axial shape so as to protrude from the main body along the axis and forming an insertion groove into which the resin tube is inserted between the main body and the tubular portion, the protrusion having a base portion extending from a bottom of the insertion groove along the axis and having a constant outer diameter, and a tip portion whose outer diameter gradually decreases from the base portion toward a tip, and in a non-inserted state in which the protrusion portion is not inserted into the liquid supply flow path of the resin tube, the outer diameter of the base portion is larger than the inner diameter of the liquid supply flow path, and The outer diameter of the resin tube but the tip of the protrusion is positioned closer to the main body than the tip of the tubular portion, and the method comprises: a coating step of applying adhesive to at least one of the outer peripheral surface of the end of the resin tube and the inner peripheral surface of the tubular portion; an insertion step of inserting the protrusion into the liquid supply flow path of the resin tube to which the adhesive has been applied in the coating step; and a joining step of hardening the adhesive applied in the coating step and joining the outer peripheral surface of the resin tube into which the protrusion has been inserted in the insertion step to the inner peripheral surface of the tubular portion, wherein the insertion step forms a seal area between the resin tube, which has been elastically deformed by insertion of the protrusion into the liquid supply flow path, and the base.

[0017] According to a method for assembling a joint unit according to one aspect of the present invention, an adhesive is applied to at least one of the outer circumferential surface of the end of the resin tube and the inner circumferential surface of the cylindrical portion in the application step, and then a protrusion is inserted into the liquid supply flow path of the resin tube in the insertion step. When the protrusion is inserted into the liquid supply flow path of the resin tube, the protrusion is positioned on the same axis as the central axis of the cylindrical portion. Therefore, an operator can easily insert the protrusion into the liquid supply flow path without visually checking the liquid supply flow path formed in the resin tube. In addition, the adhesive is hardened in the joining step to join the outer circumferential surface of the resin tube and the inner circumferential surface of the cylindrical portion. Effect of the Invention

[0018] According to the present invention, there is provided a joint structure that allows an operator to easily insert a protrusion into a liquid supply flow path without visually checking the liquid supply flow path formed in a resin tube. Equipped A coupling unit and a method for assembling the coupling unit may be provided. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is a vertical cross-sectional view showing a joint unit according to a first embodiment of the present invention. [Diagram 2] 2 is a vertical cross-sectional view showing a state in which a mounting nut has been removed from the joint unit shown in FIG. 1. [Diagram 3] FIG. 2 is a side view of the joint structure shown in FIG. 1, viewed from the resin tube side. [Figure 4] 4 is a view taken along the arrow AA of the joint structure shown in FIG. 3, showing a state before a resin tube is inserted. [Diagram 5] 4 is a view taken along the line AA of the joint structure shown in FIG. 3, showing a state in which a part of the resin tube is inserted into the cylindrical portion. [Figure 6] 4 is a view taken along the line AA of the joint structure shown in FIG. 3, showing a state in which the tip of the protrusion is inserted into the liquid-transporting flow path of the resin tube. [Figure 7] 4 is a view taken along the arrow AA of the joint structure shown in FIG. 3, showing a state in which the insertion of the resin tube has been completed. [Figure 8] FIG. 6 is a vertical cross-sectional view showing a joint unit according to a second embodiment of the present invention. [Figure 9] FIG. 11 is a vertical cross-sectional view showing a joint unit according to a third embodiment of the present invention, with a main body, a ferrule, and a mounting nut disassembled. [Figure 10] FIG. 11 is a vertical cross-sectional view showing a joint unit according to a third embodiment of the present invention, illustrating a state before a resin tube is inserted. [Figure 11] FIG. 11 is a vertical cross-sectional view showing a joint unit according to a third embodiment of the present invention, illustrating a state in which insertion of a resin tube has been completed. [Figure 12] FIG. 11 is a vertical cross-sectional view showing a joint unit according to a third embodiment of the present invention, illustrating a state in which tightening of the mounting nut has been completed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] [First embodiment] Hereinafter, a joint unit 400 according to a first embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a vertical cross-sectional view showing the joint unit 400 according to this embodiment. Fig. 2 is a vertical cross-sectional view showing a state in which a mounting nut 150 is removed from the joint unit 400 shown in Fig. 1. Fig. 3 is a side view of the joint structure 100 shown in Fig. 1, seen from the resin tube 200 side. Fig. 4 is a view taken along the arrow AA of the joint structure 100 shown in Fig. 3, showing a state before the resin tube 200 is inserted.

[0021] As shown in Fig. 1, a joint unit 400 of this embodiment includes a joint structure 100, a resin tube 200, and a resin tube 300. The joint structure 100 is a structure to which an end of the resin tube 200 is attached to one end side (the right side in Fig. 1) and an end of the resin tube 300 is attached to the other end side (the left side in Fig. 1). The joint structure 100 connects a liquid supply flow path 210 of the resin tube 200 and a liquid supply flow path 310 of the resin tube 300 so that liquid flows between them.

[0022] The joint structure 100 has a main body 110, a tubular portion 120, a protrusion 130, a female threaded portion 140, a mounting nut 150, and a ferrule 160. A connecting flow path 100a is formed in the main body 110, the protrusion 130, and the female threaded portion 140, the connecting flow path 100a extending along the axis X and connecting the liquid supply flow path 210 of the resin tube 200 and the liquid supply flow path 310 of the resin tube 300.

[0023] The main body 110 is disposed between the cylindrical portion 120, the protruding portion 130, and the female screw portion 140, and a connecting flow path 100a is formed inside the main body 110. The main body 110 is integrally formed with the cylindrical portion 120, the protruding portion 130, and the female screw portion 140 from a resin material (e.g., PVC (polyvinyl chloride), polycarbonate).

[0024] The tube portion 120 is formed in a cylindrical shape so as to protrude from the main body portion 110 toward the resin tube 200 along the axis X. As shown in Fig. 2 and Fig. 3, the tube portion 120 has a cylindrical inner peripheral surface 121 that holds the outer peripheral surface 201 of the resin tube 200.

[0025] The protrusion 130 is formed in an axial shape so as to protrude from the main body 110 toward the resin tube 200 along the axis X. As shown in FIG. 4, the protrusion 130 has a base 131 with an outer diameter Dpo and a tip 132 whose outer diameter gradually decreases toward the tip. As shown in FIGS. 3 and 4, the protrusion 130 forms an insertion groove 133 between the cylindrical portion 120 and the protrusion 130, into which the resin tube 200 is inserted. A bottom 133a of the insertion groove 133 is the boundary between the main body 110 and the protrusion 130.

[0026] 4, the boundary position on the axis X between the main body 110 and the protrusion 130 is X1, the position of the protrusion 130 on the axis X is X2, and the position of the tube portion 120 on the axis X is X3. In this case, X2, which is the tip of the protrusion 130, is located closer to X1, which is the position of the end of the main body 110 on the protrusion 130 side, than X3, which is the tip of the tube portion 120.

[0027] 4, the length L2 from the tip of the protrusion 130 to the tip of the tube portion 120 is the length L2 in the axial direction X from X2 to X3. The inner diameter of the tube portion 120 is Dci. It is desirable that the length L2 from the tip of the protrusion 130 to the tip of the tube portion 120 be 0.2 times or more the inner diameter Dci of the tube portion 120.

[0028] By setting the length L2 to be 0.2 times or more the inner diameter Dci, the end of the resin tube 200 comes into contact with the tip of the protrusion 130 in a state where the end of the resin tube 200 is inserted a sufficient length L2 relative to the inner diameter Dci of the cylindrical portion 120. Therefore, the protrusion 130 can be inserted into the liquid sending flow path 210 in a state where the outer circumferential surface of the resin tube 200 is securely held by the inner circumferential surface of the cylindrical portion 120.

[0029] As shown in FIG. 4, the length of the protrusion 130 along the axis X is the length L1 in the axis X direction from X1 to X2. The outside diameter of the protrusion 130 is Dpo. The length L1 of the protrusion 130 is preferably three times or more the outside diameter Dpo of the protrusion 130. When the length L1 of the protrusion 130 is three times or more the outside diameter Dpo of the protrusion 130, the protrusion 130 becomes needle-shaped and protrudes from the main body 110. By inserting the needle-shaped protrusion 130 into the liquid supply flow path 210 of the resin tube 200, a seal area of ​​sufficient length can be provided between the outer circumferential surface of the protrusion 130 and the liquid supply flow path 210.

[0030] The female threaded portion 140 is a member that is connected to the main body portion 110 and extends in a cylindrical shape along the axis X, with a female thread 141 formed on the outer circumferential surface. An insertion hole 142 into which an end of the resin tube 300 is inserted is formed in the center portion along the axis X of the female threaded portion 140. The end of the insertion hole 142 on the main body portion 110 side is connected to the connecting flow path 100a.

[0031] 2, a tapered portion 142a into which the tip of the ferrule 160 is inserted is provided at the end of the insertion hole 142 on the resin tube 300 side. The tapered portion 142a is shaped so that the outer diameter around the axis X gradually decreases at a constant gradient from the end of the female thread portion 140 on the resin tube 300 side toward the connecting flow path 100a.

[0032] The mounting nut 150 is a member that is detachably attached to the female thread portion 140, and is formed in a cylindrical shape along the axis X with a male thread 151 formed on its inner circumferential surface. The worker attaches the mounting nut 150 to the female thread portion 140 by engaging the male thread 151 with the female thread 141 while rotating the mounting nut 150 around the axis X.

[0033] The mounting nut 150 has a through hole 152 formed therein for passing the resin tube 300 therethrough. As shown in Fig. 2, the worker inserts the resin tube 300 so that it passes through the through hole 152, and attaches the ferrule 160 to the resin tube 300 that has passed through the through hole 152. Thereafter, the worker inserts the resin tube 300 into the insertion hole 142 of the female thread portion 140, and attaches the mounting nut 150 to the female thread portion 140, resulting in the attached state shown in Fig. 1.

[0034] The ferrule 160 is a cylindrical resin (for example, PTFE (polytetrafluoroethylene)) member inserted between the outer circumferential surface of the resin tube 300 and the tapered portion 142a of the female thread portion 140. As shown in Fig. 2, the end of the ferrule 160 on the female thread portion 140 side is formed with a tapered tip portion 161 whose outer diameter gradually decreases toward the insertion hole 142.

[0035] As shown in Fig. 2, when the mounting nut 150 is not attached to the female thread portion 140, the ferrule 160 is movable in the direction of the axis X relative to the resin tube 300. When the mounting nut 150 is attached to the female thread portion 140, the tip portion 161 of the ferrule 160 comes into contact with the tapered portion 142a, and the inner diameter of the ferrule 160 gradually decreases. As the inner diameter decreases, the ferrule 160 firmly holds the outer circumferential surface of the resin tube 300. When the mounting state shown in Fig. 1 is reached, the resin tube 300 does not move in the direction of the axis X relative to the ferrule 160.

[0036] The resin tube 200 is a tubular body having a liquid supply flow path 210 formed therein and extending along the axis X, and having a circular cross section perpendicular to the axis X. The resin tube 200 is made of a resin material such as PVC (polyvinyl chloride), silicone, or PharMed. The resin tube 200 is attached to a cylindrical portion 120 and a protruding portion 130 disposed at an end of the joint structure 100.

[0037] 4, in a non-inserted state in which the protrusion 130 of the joint structure 100 is not inserted into the liquid supply flow path 210 of the resin tube 200, the outer diameter Dpo of the protrusion 130 is larger than the inner diameter Dti of the liquid supply flow path 210 of the resin tube 200. In addition, the outer diameter Dto of the resin tube 200 is smaller than the inner diameter Dci of the cylindrical portion 120.

[0038] The thickness T1 of the resin tube 200 is (Dto-Dti) / 2. The distance L3 between the inner peripheral surface of the tubular portion 120 and the outer peripheral surface of the protruding portion 130 is (Dci-Dpo) / 2. The thickness T1 of the resin tube 200 is the same as the distance L3 or is slightly smaller than the distance L3. By setting such a relationship, when the resin tube 200 is inserted into the protruding portion 130, the outer peripheral surface of the resin tube 200 comes into contact with the inner peripheral surface of the tubular portion 120 or is close to it with a small gap therebetween.

[0039] In the non-inserted state, the outer diameter Dto of the resin tube 200 is 3 times or more and 15 times or less than the inner diameter Dti. Also, the outer diameter Dto of the resin tube 200 is preferably 7 times or more and 8 times or less than the inner diameter Dti. Since the outer diameter Dto of the resin tube 200 is sufficiently larger than the inner diameter Dti, the resin tube 200 has a sufficient thickness T1.

[0040] The resin tube 200 of this embodiment can be suitably used in, for example, a tube pump (peristaltic pump). In the tube pump, the resin tube 200 is installed in a tube holding mechanism (not shown) having a cylindrical inner circumferential surface. The tube pump has a roller member that rotates while in contact with the resin tube 200, and the resin tube 200 is crushed between the cylindrical inner circumferential surface and the roller member, thereby circulating the fluid inside the resin tube 200. As described above, the resin tube 200 of this embodiment has a sufficient thickness T1, and therefore can exhibit sufficient rigidity and the associated durability even in cases where durability against the pressing force of the roller member is required.

[0041] The resin tube 200 has an inner diameter Dti of 0.1 mm or more and 1.0 mm or less. Since the inner diameter Dti of the resin tube 200 is extremely small, 0.1 mm or more and 1.0 mm or less, the flow rate of the liquid flowing through the liquid sending flow path 210 formed in the resin tube 200 per unit time can be kept small.

[0042] The resin tube 300 is a tubular body having a liquid delivery flow path 310 formed therein and extending along the axis X, and having a circular cross section perpendicular to the axis X. The resin tube 300 is made of a resin material such as PVC (polyvinyl chloride), silicone, or PharMed. The resin tube 300 is attached to the female thread portion 140 disposed at the end of the joint structure 100.

[0043] Next, a method for assembling the joint unit 400 of this embodiment will be described with reference to the drawings. Fig. 4 to Fig. 7 are views taken along the line AA of the joint structure 100 shown in Fig. 3, and Fig. 4 shows the state before the resin tube 200 is inserted. Fig. 5 shows the state in which a part of the resin tube 200 is inserted into the cylindrical portion 120. Fig. 6 shows the state in which the tip of the protrusion 130 is inserted into the liquid sending flow path 210 of the resin tube 200, and Fig. 7 shows the state in which the insertion of the resin tube 200 is completed.

[0044] The method of assembling the joint unit 400 of this embodiment involves attaching an end of the resin tube 200 to one end side (the right side in FIG. 1) of the joint structure 100, and attaching an end of the resin tube 300 to the other end side (the left side in FIG. 1). First, a method of attaching the end of the resin tube 200 to one end side (the right side in FIG. 1) of the joint structure 100 will be described.

[0045] 4, before inserting the resin tube 200 into the joint structure 100, an operator applies an adhesive UA (e.g., an ultraviolet-curing adhesive) to the outer peripheral surface of the end of the resin tube 200 (application step). The adhesive UA may be applied to both the outer peripheral surface of the end of the resin tube 200 and the inner peripheral surface of the tubular portion 120. The adhesive UA may also be applied to the inner peripheral surface of the tubular portion 120 rather than to the outer peripheral surface of the end of the resin tube 200.

[0046] Next, the worker holds both the resin tube 200 and the joint structure 100, and inserts the end of the resin tube 200 coated with the adhesive UA into the inner periphery of the tubular portion 120 of the joint structure 100. As shown in FIG. 5, the end of the resin tube 200 comes into contact with the tip portion 132 of the protrusion portion 130 of the joint structure 100. In the state shown in FIG. 5, the outer periphery of the resin tube 200 is held by the inner periphery of the tubular portion 120. That is, even if the worker moves the resin tube 200 in a direction perpendicular to the axis X, the outer periphery of the resin tube 200 comes into contact with the inner periphery of the tubular portion 120, and the state in which the resin tube 200 is disposed on the inner periphery of the tubular portion 120 is maintained.

[0047] Next, while holding both the resin tube 200 and the joint structure 100, the worker pushes the end of the resin tube 200 toward the bottom 133a of the insertion groove 133. As shown in Fig. 6, when the end of the resin tube 200 is pushed toward the bottom 133a of the insertion groove 133, the tip 132 of the protrusion 130 of the joint structure 100 is inserted into the liquid supply flow path 210 of the resin tube 200 (insertion step).

[0048] When pushing the end of the resin tube 200 toward the bottom 133a of the insertion groove 133, if the tubular portion 120 is not present, the action of the operator when pushing the resin tube 200 may cause the position of the tip 132 of the protrusion 130 to deviate from the position of the liquid supply flow path 210 of the resin tube 200. In this embodiment, the outer peripheral surface of the resin tube 200 is held by the inner peripheral surface of the tubular portion 120, so that the position of the tip 132 of the protrusion 130 is prevented from deviating from the position of the liquid supply flow path 210 of the resin tube 200.

[0049] The worker further pushes the end of the resin tube 200 from the state shown in Fig. 6 toward the bottom 133a of the insertion groove 133 to bring about the state shown in Fig. 7 in which both the tip 132 and the base 131 of the protrusion 130 are inserted into the liquid sending flow path 210 of the resin tube 200 (insertion step). In the state shown in Fig. 7, the end of the resin tube 200 comes into contact with the bottom 133a of the insertion groove 133.

[0050] 7, the worker hardens the adhesive UA (not shown) present between the outer peripheral surface of the resin tube 200 and the inner peripheral surface of the tubular portion 120 to join the outer peripheral surface of the resin tube 200 and the inner peripheral surface of the tubular portion 120 (joining process). The worker hardens the adhesive UA by irradiating the area where the adhesive UA is present with ultraviolet light using an ultraviolet irradiator (not shown).

[0051] When a dry-hardening adhesive is used, the adhesive present between the outer circumferential surface of the resin tube 200 and the inner circumferential surface of the cylindrical portion 120 is left to dry and harden. Through the above operations, the end of the resin tube 200 is attached to one end side (the right side in FIG. 1) of the joint structure 100. Next, a method for attaching the end of the resin tube 300 to the other end side (the left side in FIG. 1) of the joint structure 100 will be described.

[0052] 2, the worker inserts the resin tube 300 into the through hole 152 with the mounting nut 150 not attached to the female thread portion 140. The worker also attaches the ferrule 160 to the resin tube 300 that has passed through the through hole 152. After that, the worker inserts the end of the resin tube 300 into the insertion hole 142 of the female thread portion 140 so that the tip portion 161 of the ferrule 160 comes into contact with the tapered portion 142a.

[0053] The worker attaches the mounting nut 150 to the female thread portion 140 by engaging the male thread 151 with the female thread 141 while rotating the mounting nut 150 around the axis X, thereby achieving the attached state shown in Fig. 1. In the attached state shown in Fig. 1, the liquid supply flow path 210 of the resin tube 200 and the liquid supply flow path 310 of the resin tube 300 are connected via the connecting flow path 100a of the joint structure 100 so that liquid can flow therethrough.

[0054] The functions and effects of the present embodiment described above will now be described. According to the joint structure 100 of the present embodiment, the protrusion 130 forms an insertion groove 133 into which the resin tube 200 is inserted between the protrusion 130 and the tubular portion 120 that holds the outer circumferential surface of the resin tube 200, and the tip of the protrusion 130 is disposed at a position closer to the main body portion 110 than the tip of the tubular portion 120. Therefore, when the end of the resin tube 200 is brought closer to the joint structure 100, the outer circumferential surface of the resin tube 200 is held by the inner circumferential surface of the tubular portion 120 before the end of the resin tube 200 comes into contact with the tip of the protrusion 130. By holding the outer circumferential surface of the resin tube 200 on the inner circumferential surface of the tubular portion 120, the liquid supply flow path 210 formed in the resin tube 200 is disposed on the axis X that is the same as the central axis of the tubular portion 120.

[0055] Since the protrusion 130 is disposed on the same axis X as the central axis of the tubular portion 120, the liquid supply flow path 210 formed in the resin tube 200 and the protrusion 130 are disposed on the same axis. When the worker presses the resin tube 200 toward the main body 110 of the joint structure 100 in this state, the protrusion 130 disposed on the same axis is inserted into the liquid supply flow path 210. In this way, the worker can easily perform the operation of inserting the protrusion 130 into the liquid supply flow path 210 without visually checking the liquid supply flow path 210 formed in the resin tube 200.

[0056] In the joint structure 100 of this embodiment, the length L1 of the protrusion 130 along the axis X is three times or more the outer diameter Dpo of the protrusion 130. Therefore, the protrusion 130 is needle-shaped and protrudes from the main body 110. By inserting the needle-shaped protrusion 130 into the liquid supply flow path 210 of the resin tube 200, a seal area of ​​sufficient length can be provided between the outer circumferential surface of the protrusion 130 and the liquid supply flow path 210. In addition, it is a difficult task for an operator to insert the needle-shaped protrusion 130 into the liquid supply flow path 210 while visually checking it, but since the protrusion 130 is inserted into the liquid supply flow path 210 with the liquid supply flow path 210 and the protrusion 130 arranged on the same axis, the operator can easily perform the task of inserting the protrusion 130 into the liquid supply flow path 210.

[0057] In the joint unit 400 of this embodiment, the outer diameter Dpo of the protrusion 130 is larger than the inner diameter Dti of the liquid supply flow path 210. Therefore, when the protrusion 130 is inserted into the liquid supply flow path 210, the inner diameter Dti of the liquid supply flow path 210 is elastically deformed to expand to the outer diameter Dpo of the protrusion 130. The resin tube 200 forms a seal area between itself and the outer peripheral surface of the protrusion 130 due to a contraction force caused by the elastic deformation. In addition, since the outer diameter Dto of the resin tube 200 is smaller than the inner diameter Dci of the cylindrical portion 120, the resin tube 200 can be inserted into the insertion groove 133 even if the outer diameter Dto of the resin tube 200 expands with the expansion of the inner diameter Dti of the liquid supply flow path 210.

[0058] In the joint unit 400 of this embodiment, the outer diameter Dto of the resin tube 200 is 3 times or more and 15 times or less than the inner diameter Dti of the resin tube 200. Since the outer diameter Dto of the resin tube 200 is sufficiently larger than the inner diameter Dti, the resin tube 200 has a sufficient thickness T1. Therefore, even when durability against the pressing force of the roller is required, such as when used in a tube pump, the resin tube 200 can exhibit sufficient rigidity and the durability associated therewith. In addition, when a resin tube 200 with high rigidity is used, it is difficult to insert the protrusion 130 and elastically deform it, but the protrusion 130 can be inserted into the liquid sending flow path 210 with the outer circumferential surface of the resin tube 200 held by the inner circumferential surface of the cylindrical portion 120.

[0059] In the joint unit 400 of this embodiment, the resin tube 200 has an inner diameter Dti of 0.1 mm or more and 1.0 mm or less. Since the inner diameter Dti of the resin tube is extremely small, the flow rate of the liquid flowing through the flow path formed in the resin tube 200 per unit time can be kept small. Even if the inner diameter Dti of the resin tube 200 is extremely small, the protrusion 130 can be easily inserted into the liquid supply flow path 210 formed in the resin tube 200 without visually checking the liquid supply flow path 210.

[0060] According to the assembly method of the joint unit 400 of this embodiment, in a state where an adhesive is applied to at least one of the outer peripheral surface of the end of the resin tube 200 and the inner peripheral surface of the tubular portion 120 in the application process, the protrusion 130 is inserted into the liquid supply flow path 210 of the resin tube 200 in the insertion process. When the protrusion 130 is inserted into the liquid supply flow path 210 of the resin tube 200, the protrusion 130 is arranged on the axis X which is the same as the central axis of the tubular portion 120. Therefore, the worker can easily perform the work of inserting the protrusion 130 into the liquid supply flow path 210 without visually checking the liquid supply flow path 210 formed in the resin tube 200. In addition, the adhesive is hardened in the joining process to join the outer peripheral surface of the resin tube 200 and the inner peripheral surface of the tubular portion 120.

[0061] Second Embodiment Next, a joint unit 400A according to a second embodiment of the present invention will be described with reference to the drawings. Fig. 8 is a vertical cross-sectional view showing a joint unit 400A according to a second embodiment of the present invention. This embodiment is a modification of the first embodiment, and is the same as the first embodiment except as otherwise specifically described below, and therefore the description below will be omitted.

[0062] The joint structure 100 of the joint unit 400 of the first embodiment was provided with the female thread portion 140 and the mounting nut 150 for connecting the resin tube 300. In contrast, the joint unit 400A of the present embodiment does not have components equivalent to the female thread portion 140 and the mounting nut 150, and instead includes a tubular portion 170 and a protrusion portion 180.

[0063] As shown in Fig. 8, the joint unit 400A of this embodiment includes a joint structure 100A, a resin tube 200, and a resin tube 300A. The joint structure 100A is a structure to which an end of the resin tube 200 is attached to one end side (the right side in Fig. 8) and an end of the resin tube 300A is attached to the other end side (the left side in Fig. 8). The joint structure 100A connects the liquid supply flow path 210 of the resin tube 200 and the liquid supply flow path 310A of the resin tube 300A so that liquid flows between them.

[0064] The joint structure 100A has a main body 110, a tubular portion 120, a protrusion 130, a tubular portion 170, and a protrusion 180. A connecting flow path 100Aa is formed in the main body 110, the protrusion 130, and the protrusion 180, and extends along the axis X and connects the liquid supply flow path 210 of the resin tube 200 and the liquid supply flow path 310A of the resin tube 300A. The main body 110, the tubular portion 120, and the protrusion 130 are similar to those in the first embodiment, and therefore will not be described below.

[0065] The tube portion 170 is formed in a cylindrical shape so as to protrude from the main body portion 110 toward the resin tube 300A along the axis X. As shown in Fig. 8, the tube portion 170 has a cylindrical inner circumferential surface 171 that holds the outer circumferential surface 301A of the resin tube 300.

[0066] The protrusion 180 is formed in an axial shape so as to protrude from the main body 110 toward the resin tube 300A along the axis X. As shown in FIG. 8, the protrusion 180 has a base 181 and a tip 182 whose outer diameter gradually decreases toward the tip. As shown in FIG. 8, the protrusion 180 forms an insertion groove 183 between the cylindrical portion 170 and the protrusion 180, into which the resin tube 300A is inserted. A bottom 183a of the insertion groove 183 is the boundary between the main body 110 and the protrusion 180. The shape of the protrusion 180 is the same as that of the protrusion 130, and therefore will not be described below.

[0067] The resin tube 300A is a tubular body having a liquid delivery flow path 310A extending along the axis X formed therein and a circular cross section perpendicular to the axis X. The resin tube 300 is made of a resin material such as PVC (polyvinyl chloride), silicone, or PharMed. The resin tube 300A is attached to a cylindrical portion 170 and a protruding portion 180 disposed at an end of the joint structure 100A. The shape of the resin tube 300A is similar to that of the resin tube 200, and therefore will not be described below.

[0068] In the method of assembling the joint unit 400A of this embodiment, an end of the resin tube 200 is attached to one end side (right side in FIG. 8) of the joint structure 100A, and an end of the resin tube 300A is attached to the other end side (left side in FIG. 8). The method of attaching the end of the resin tube 200 to one end side of the joint structure 100A is similar to the method of attaching the resin tube 200 to one end side of the joint structure 100 of the first embodiment, and therefore a description thereof will be omitted below. In addition, the method of attaching the end of the resin tube 300A to the other end side of the joint structure 100A is similar to the method of attaching the end of the resin tube 200 to one end side of the joint structure 100A, and therefore a description thereof will be omitted below.

[0069] According to this embodiment, one end side (right side in Figure 8) and the other end side (left side in Figure 8) of the joint structure 100A have the same structure, and an end side of the resin tube 200 can be attached to the one end side, and an end side of the resin tube 300A can be attached to the other end side.

[0070] Third Embodiment Next, a joint unit 400B according to a third embodiment of the present invention will be described with reference to the drawings. This embodiment is a modified example of the first embodiment, and is the same as the first embodiment except where specifically described below, and therefore the description below will be omitted.

[0071] In the joint structure 100 of the joint unit 400 of the first embodiment, the main body 110, the tubular portion 120 that holds the outer circumferential surface of the resin tube 300, and the protrusion 130 are integrally formed from a resin material. In contrast, in the joint unit 400B of the present embodiment, the main body 110B and the protrusion 130B are integrally formed, and the cylindrical ferrule 120B is a separate component from the main body 110B and the protrusion 130B.

[0072] 9 to 12 are longitudinal cross-sectional views showing a joint unit 400B according to this embodiment. Fig. 9 shows a state in which the main body 110B, the ferrule 120B, and the mounting nut 150B are disassembled. Fig. 10 shows a state before the resin tube 200 is inserted. Fig. 11 shows a state after the insertion of the resin tube 200 is completed. Fig. 12 shows a state after the fastening of the mounting nut 150B is completed.

[0073] 9 shows the structure of one end side (the right side in FIG. 9) of the joint unit 400B of this embodiment, and omits the structure of the other end side (the left side in FIG. 9) of the joint unit 400B of this embodiment. The structure of the other end side of the joint unit 400B is assumed to be similar to the structure of the left side in FIG. 1 of the first embodiment, and the following description will be omitted.

[0074] As shown in FIG. 9, a joint structure 100B of a joint unit 400B of this embodiment includes a main body portion 110B, a ferrule (tubular portion) 120B, a protrusion portion 130B, and a mounting nut 150B.

[0075] The main body 110B is integrally formed with the protrusion 130B, and a connecting flow passage 100Ba is formed inside. A female thread 111B is formed on the outer circumferential surface of the main body 110B. In the main body 110B, a tapered portion 112B is formed on the outer circumferential side of the protrusion 130B, the inner diameter of which gradually increases toward the tip side.

[0076] The protrusion 130B is formed in an axial shape so as to protrude from the main body 110B toward the resin tube 200 along the axis X. As shown in Fig. 9, the protrusion 130B has a base 131B and a tip 132B whose outer diameter gradually decreases toward the tip.

[0077] The ferrule 120B is a cylindrical resin (e.g., PTFE) member inserted between the outer circumferential surface of the resin tube 200 and the tapered portion 112B of the main body 110B. As shown in Fig. 9, the end of the ferrule 120B on the main body 110B side is formed with a tapered tip portion 121B whose outer diameter gradually decreases toward the tip.

[0078] The mounting nut 150B is a member that is detachably attached to the female thread 111B of the main body 110B, and is formed in a cylindrical shape along the axis X with a male thread 151B formed on its inner circumferential surface. The worker attaches the mounting nut 150B to the main body 110B by engaging the male thread 151B with the female thread 111B while rotating the mounting nut 150B about the axis X. A through hole 152B is formed in the mounting nut 150B to allow the resin tube 200 to pass therethrough.

[0079] Next, a method for assembling the joint unit 400B of the embodiment will be described with reference to the drawings. In the method for assembling the joint unit 400B of the present embodiment, an end of the resin tube 200 is attached to one end side (the right side in FIG. 9) of the joint structure 100B, and an end of the resin tube is attached to the other end side (the left side in FIG. 9). Below, a method for attaching the end of the resin tube 200 to one end side (the right side in FIG. 9) of the joint structure 100B will be described.

[0080] Prior to attaching the resin tube 200, the worker attaches the mounting nut 150B to the main body 110B by engaging the male thread 151B with the female thread 111B while rotating the mounting nut 150B around the axis X. This results in a state in which the ferrule 120B is sandwiched between the mounting nut 150B and the main body 110B, as shown in FIG.

[0081] 10, the fastening of the mounting nut 150B to the main body 110B is not complete, and a gap GA is provided between the mounting nut 150B and the main body 110B along the axis X. In addition, in the state shown in FIG. 10, the inner diameter Dfi of the ferrule 120B is larger than the outer diameter Dto of the resin tube 200. Therefore, the worker can insert the resin tube 200 into the inner periphery of the ferrule 120B.

[0082] Next, the worker holds both the resin tube 200 and the joint structure 100B, and inserts the end of the resin tube 200 into the inner periphery of the ferrule 120B of the joint structure 100B. When the end of the resin tube 200 contacts the tip 132B of the protrusion 130B of the joint structure 100B, the outer periphery of the resin tube 200 is held by the inner periphery of the ferrule 120B. That is, even if the worker moves the resin tube 200 in a direction perpendicular to the axis X, the outer periphery of the resin tube 200 contacts the inner periphery of the ferrule 120B, and the state in which the resin tube 200 is disposed on the inner periphery of the ferrule 120B is maintained.

[0083] Next, while holding both the resin tube 200 and the joint structure 100B, the worker pushes the end of the resin tube 200 into between the ferrule 120B and the protrusion 130B. As shown in Fig. 11, when the end of the resin tube 200 is pushed in, the base 131B and the tip 132B of the protrusion 130B of the joint structure 100B are inserted into the liquid supply flow path 210 of the resin tube 200 (insertion step).

[0084] When pushing the end of the resin tube 200 towards the protrusion 130B, if the ferrule 120B is not present, the action of the operator when pushing the resin tube 200 may cause the position of the tip 132B of the protrusion 130B to deviate from the position of the liquid supply flow path 210 of the resin tube 200. In this embodiment, the outer circumferential surface of the resin tube 200 is held by the inner circumferential surface of the ferrule 120B, so that the position of the tip 132B of the protrusion 130B is prevented from deviating from the position of the liquid supply flow path 210 of the resin tube 200.

[0085] Next, the worker rotates the mounting nut 150B around the axis X to narrow the gap GA provided between the mounting nut 150B and the main body 110B. As the gap GA narrows, the inner diameter of the tip 121B of the ferrule 120B that contacts the tapered portion 112B of the main body 110B decreases. As a result, the end of the resin tube 200 is sandwiched between the tip 121B of the ferrule 120B and the protrusion 130B. When the gap GA provided between the mounting nut 150B and the main body 110B disappears, the mounting nut 150B and the main body 110B come into contact with each other, and the fastening of the mounting nut 150B to the main body 110B is completed.

[0086] According to the joint unit 400B of the present embodiment described above, an operator can easily insert the protrusion 130B into the liquid supply flow path 210 without visually checking the liquid supply flow path 210 formed in the resin tube 200. In addition, the resin tube 200 can be held by the ferrule 120B so that the resin tube 200 does not come off the protrusion 130B without using an adhesive.

[0087] Furthermore, according to the joint unit 400B of this embodiment, when removing the resin tube 200, the worker rotates the mounting nut 150B about the axis X in the opposite direction to that used for fastening, thereby widening the gap GA provided between the mounting nut 150B and the main body 110B. As the gap GA widens, the inner diameter of the tip portion 121B of the ferrule 120B that contacts the tapered portion 112B of the main body 110B increases.

[0088] This releases the end of the resin tube 200 from being clamped between the tip portion 121B of the ferrule 120B and the protrusion 130B. The worker can remove the resin tube 200 from the joint unit 400B by pulling out the resin tube 200, which has been released from being clamped between the tip portion 121B of the ferrule 120B and the protrusion 130B, along the axis X.

[0089] Other Embodiments The joint unit of the present embodiment is preferably used in a tube pump that circulates a liquid inside a resin tube while squeezing the resin tube, but may be used in other forms. For example, it may be used for purposes other than tube pumps. In addition, it may be used simply to connect two flow paths formed by resin tubes. [Explanation of symbols]

[0090] 100, 100A, 100B joint structure 100a, 100Aa, 100Ba connecting flow path 110,110B Main body 120,170 Cylindrical part 120B Ferrule (Cylindrical part) 130,130B,180 Protrusion 131,131B,181 Base 132,132B,182 Tip 140 Female thread 150,150B Mounting nut 160 Ferrule 183 Insertion groove 200 Plastic tube 210 Liquid delivery channel 300,300A Plastic Tube 310,310A Liquid delivery channel 400, 400A, 400B coupling unit GA Gap UA Adhesive X axis

Claims

1. a resin tube having a liquid delivery flow path extending along an axis and a circular cross section perpendicular to the axis; A joint structure attached to an end of the resin tube, The joint structure includes: A main body portion, a cylindrical portion that is formed in a cylindrical shape so as to protrude from the main body portion along the axis line and that holds an outer circumferential surface of the resin tube; a protrusion portion formed in an axial shape so as to protrude from the main body portion along the axis line, the protrusion portion forming an insertion groove into which the resin tube is inserted between the main body portion and the tubular portion, a connecting flow path extending along the axis and connecting the liquid supply flow path to another flow path is formed in the main body and the protrusion, a tip of the protrusion is disposed closer to the main body than a tip of the tube portion, a length of the protrusion along the axis is three times or more the outer diameter of the protrusion; the protrusion has a base portion that extends from a bottom portion of the insertion groove along the axis and has a constant outer diameter, and a tip portion whose outer diameter gradually decreases from the base portion toward the tip, an outer diameter of the base portion is larger than an inner diameter of the liquid supply flow path in a non-inserted state in which the protrusion portion is not inserted into the liquid supply flow path of the resin tube; A joint unit in which a seal area is formed between the resin tube and the base portion when the protrusion is inserted into the liquid supply flow path and elastically deformed.

2. The joint unit according to claim 1 , wherein a length from a tip of the protrusion to a tip of the cylindrical portion is at least 0.2 times an inner diameter of the cylindrical portion.

3. A fitting unit as described in claim 1 or claim 2, wherein in a non-inserted state in which the protrusion is not inserted into the fluid delivery flow path of the plastic tube, the outer diameter of the protrusion is larger than the inner diameter of the fluid delivery flow path and the outer diameter of the plastic tube is smaller than the inner diameter of the tubular portion.

4. 4. The joint unit according to claim 3, wherein an outer diameter of the resin tube is 3 times or more and 15 times or less than an inner diameter of the resin tube.

5. The joint unit according to claim 4, wherein the resin tube has an inner diameter of 0.1 mm or more and 1.0 mm or less.

6. A method for assembling a joint unit including a resin tube having a liquid supply flow path extending along an axis and a circular cross section perpendicular to the axis, and a joint structure attached to an end of the resin tube, comprising: The joint structure includes: A main body portion, a cylindrical portion that is formed in a cylindrical shape so as to protrude from the main body portion along the axis line and that holds an outer circumferential surface of the resin tube; a protrusion portion formed in an axial shape so as to protrude from the main body portion along the axis line, the protrusion portion forming an insertion groove into which the resin tube is inserted between the main body portion and the tubular portion, the protrusion has a base portion that extends from a bottom portion of the insertion groove along the axis and has a constant outer diameter, and a tip portion whose outer diameter gradually decreases from the base portion toward the tip, in a non-inserted state in which the protrusion is not inserted into the liquid supply flow path of the resin tube, an outer diameter of the base is larger than an inner diameter of the liquid supply flow path, and an outer diameter of the resin tube is smaller than an inner diameter of the cylindrical portion, a tip of the protrusion is disposed closer to the main body than a tip of the tube portion, a length of the protrusion along the axis is three times or more the outer diameter of the protrusion; a coating step of coating an adhesive on at least one of an outer circumferential surface of the end portion of the resin tube and an inner circumferential surface of the cylindrical portion; an inserting step of inserting the protrusion into the liquid sending flow path of the resin tube to which the adhesive has been applied in the applying step; a joining process for hardening the adhesive applied in the application process and joining an outer circumferential surface of the resin tube into which the protrusion portion is inserted in the insertion process and an inner circumferential surface of the cylindrical portion, The inserting step is a method for assembling a joint unit, in which a seal area is formed between the resin tube, which has been elastically deformed by inserting the protrusion into the liquid supply flow path, and the base.

Images