JP6579701B2 - Drain tube manufacturing method - Google Patents

Description

The present invention relates to a method for producing a drain tube .

  Conventionally, a wound drain catheter in which a drain and an outflow tube are connected by a connector has been used as a surgical medical device that discharges bodily fluids such as blood accumulated in an affected part after surgery to the outside of the body (for example, patent document) 1). In the drainage of the wound drainage catheter, a partition having a cross-shaped cross section extending from the front end to the rear end is provided in the cylindrical outer wall to form four flow paths extending in the axial direction, and these four flow paths are formed on the outer wall. A slit extending along each of the flow paths is formed.

When using the wound drain catheter, for example, the drain and connector portions are inserted into the body, the drain is left in the affected area, and the rear end portion of the outflow tube is taken out of the body and connected to a suction machine or the like. To do. As a result, blood or the like accumulated in the affected area enters the flow path from the drain slit and is discharged out of the body through the outflow tube.
However, the connection of the drain and the outflow pipe by such a connector requires a connection work and is complicated to manufacture. Further, when pulling out from the body, there is a possibility that the drain is removed from the connector and remains in the body, or the outflow pipe is detached from the connector and the drain and the connector remain in the body.

  In recent years, as a surgical medical device that discharges bodily fluids such as blood to the outside of a body, for example, a suction tube portion, a connecting tube portion, and an outflow tube portion are integrally formed in order from the front end, and lead from the front end to the rear end. A drain tube having a channel formed therein is widely used. In the drain tube, a partition having a cross-shaped cross section extending from the front end of the suction tube portion to the rear end of the connection tube portion is provided in the suction tube portion and the connection tube portion. Thereby, four flow paths extending in the axial direction partitioned by the partition portion are formed inside the suction tube portion and the connecting tube portion. The plurality of flow paths merge into one at the boundary portion between the connecting pipe portion and the outflow pipe portion. In addition, four slits extending along each flow path from the front end to the rear end of the suction pipe section are formed on the outer wall of the suction pipe portion so as to correspond to each of the four flow paths. No slit is formed in the connecting pipe portion.

When using the drain tube, the suction tube portion and the connecting tube portion are inserted into the body, the suction tube portion is left in the affected area, and the rear end side portion of the outflow tube portion is taken out of the body and put into a suction machine or the like. Connecting. In the drain tube, since the suction tube portion, the connection tube portion, and the outflow tube portion are integrally formed, there is no possibility that the suction tube portion is detached from the connection tube portion when the drain tube is pulled out from the body.
It is important that the drain tube can be easily and integrally extruded from the suction tube portion, the connecting tube portion, and the outflow tube portion using an extrusion mold that is as simple as possible.

U.S. Pat. No. 4,465,481

  The present invention provides a simple extrusion mold capable of easily and integrally extruding a suction pipe section, a connecting pipe section and an outflow pipe section to obtain a drain tube, and a tube including the extrusion mold. An object is to provide a manufacturing apparatus.

The present invention has the following configuration.
[1] An extrusion mold for extruding a drain tube, a cylindrical out die, and a first in die provided in the out die so that the tip is aligned with the tip of the out die And a second indie provided on the front end side of the out die, wherein the first indie is provided around a central axis of the out die and includes a plurality of inner pieces that move in the radial direction of the out die. An annular space is formed between the out die and the first indie when the plurality of inner pieces are brought into close contact with each other when viewed from the front end side, and the second indie The out die that is provided in contact with the out die at a position corresponding to the inner piece in a front view as viewed from the above, and moves in a radial direction of the out die. A plurality of tip end piece of the columnar extending radially, extrusion molding die.
[2] A cross-sectional shape perpendicular to the length direction of the hollow portion in the out die is a circular shape, and the first in die is a fan shape having a central angle of 90 degrees when viewed from the front end side. When the four inner pieces are brought into close contact with each other, an annular space is formed between the out die and the first indie, and the second indie is viewed from the front side. The mold for extrusion molding according to [1], comprising four tip side pieces corresponding to the inner piece in view.
[3] A cross-sectional shape perpendicular to the length direction of the hollow portion in the out die is an ellipse, and the first in die moves in the short-diameter direction of the out die. In the front view seen from the front end side, the third inner piece and the fourth inner piece that move in the major axis direction on both the outer sides of the out die in the major axis direction of the first inner piece and the second inner piece, When the four inner pieces are brought into close contact with each other, an elliptical annular space is formed between the out die and the first indie, and the second indie is the above-mentioned 4 in the front view seen from the front end side. The extrusion mold according to [1], comprising four tip-side pieces corresponding to the two inner pieces.
[4] A tube manufacturing apparatus comprising: the extrusion mold according to any one of [1] to [3]; and an extruder that supplies a resin composition to the extrusion mold.

The extrusion molding die of the present invention is simple, and a drain tube can be obtained by easily extruding the suction tube portion, the connecting tube portion and the outflow tube portion integrally.
If the tube manufacturing apparatus of this invention is used, a suction tube part, a connection pipe part, and an outflow pipe part can be easily extruded integrally, and a drain tube can be obtained.

It is an example of the extrusion mold of the present invention, and is a front view showing a state at the time of forming an outflow pipe portion. It is the front view which showed the state at the time of shaping | molding of the suction pipe part in the metal mold | die for extrusion molding of FIG. It is the front view which showed the state at the time of shaping | molding of the connection pipe part in the metal mold | die for extrusion molding of FIG. It is the perspective view which showed the drain tube manufactured by the metal mold | die for extrusion molding of FIG. FIG. 5 is an enlarged perspective view of the vicinity of the tip of the drain tube of FIG. 4. It is the side view to which the periphery of the connection pipe part in the drain tube of FIG. 4 was expanded. FIG. 7A is a sectional view taken along line AA, FIG. 7B is a sectional view taken along line BB, and FIG. 7C is a sectional view taken along line CC. is there. It is the figure which showed the other example of the metal mold | die for extrusion molding of this invention, FIG. 8 (A) is the front view which showed the state at the time of shaping | molding of an outflow pipe part, FIG. 8 (B) is a suction pipe part. It is the front view which showed the state at the time of shaping | molding, and FIG.8 (C) is the front view which showed the state at the time of shaping | molding of a connection pipe part. FIG. 9 is a view showing a drain tube manufactured by the extrusion mold of FIG. 8, FIG. 9 (A) is a sectional view of a suction pipe portion, and FIG. 9 (B) is a sectional view of a connecting pipe portion. FIG. 9C is a cross-sectional view of the outflow pipe portion. It is the figure which showed the drain tube manufactured by the metal mold | die for extrusion molding of this invention, FIG. 10 (A) is the side view to which the periphery of the connection pipe part was expanded, FIG.10 (B) is a suction pipe part. It is sectional drawing, FIG.10 (C) is sectional drawing of a connection pipe part, FIG.10 (D) is sectional drawing of an outflow pipe part.

In this specification, the suction tube portion is located on the distal end side of the drain tube, and a plurality of flow paths are formed by a partition portion inside the outer wall, and the outer wall extends along one or more of the flow paths from the distal end. Means a portion where a slit is formed.
The outflow pipe portion means a portion that is located on the rear end side of the drain tube, does not have a partition portion inside the outer wall, and is not formed with a slit.
The connecting pipe portion is a portion that is located between the suction pipe portion and the outflow pipe portion in the drain tube, has a plurality of flow paths formed by the partition portion inside the outer wall, and no slit is formed. The boundary between the suction tube portion and the connecting tube portion coincides with the position of the rear end of the longest slit among the slits formed on the outer wall of the drain tube so as to extend from the tip. The boundary between the connecting pipe part and the outflow pipe part coincides with the position of the rear end of the partition part.

  The tube manufacturing apparatus of the present invention is an apparatus for manufacturing a drain tube. The tube manufacturing apparatus of the present invention includes an extrusion mold and an extruder that supplies a resin composition to the extrusion mold.

(Extrusion mold)
The extrusion mold is an extrusion mold for extruding a drain tube. Hereinafter, an example of the extrusion mold of the present invention will be described and described.
As shown in FIG. 1, the extrusion mold 100 of the present embodiment includes a cylindrical out die 110 and a first in die provided in the out die 110 so that the tip is aligned with the tip of the out die 110. 112 and a second in-die 114 provided on the front end side of the out-die 110.

The out die 110 is a cylindrical member. The cross-sectional shape perpendicular to the length direction of the hollow portion in the out die 110 is circular. The shape of the out die 110 in this example is cylindrical, but the out die may not be cylindrical, and if the cross-sectional shape of the hollow portion is a predetermined shape such as a circular shape, the overall shape is It may be a rectangular parallelepiped.
The out die 110 is supplied with a resin composition that forms a drain tube from the rear end side toward the front end side, and the resin composition is extruded from the front end of the out die 110 to form a tube.
The size of the out die 110 is not particularly limited, and may be appropriately designed according to the outer diameter of the drain tube to be manufactured.

The first in-die 112 includes four columnar inner pieces 112 a to 112 d extending in the axial direction of the out-die 110. The positions of the tips of the inner pieces 112 a to 112 d in the axial direction of the out die 110 are aligned with the tips of the out die 110.
The front view shape seen from the front end side of the inner pieces 112a to 112d is a fan shape with a central angle of 90 degrees. In a front view when the first indie 112 is viewed from the front end side, the inner pieces 112a to 112d are provided around the central axis of the out die 110 so as to abut the corners forming the central angle.

The four inner pieces 112 a to 112 d in the first in-die 112 are configured to move in the radial direction of the out-die 110.
In this example, when the four inner pieces 112a to 112d in the first indie 112 are brought into close contact with each other without any gap in the out die 110, the front view shape viewed from the front end side becomes a circular shape. At this time, an annular space 116 is formed between the out die 110 and the first in die 112. A cylindrical outer wall 10 in the drain tube 1 described later is formed by the resin composition discharged from the space 116.

  Also, as shown in FIGS. 2 and 3, when the four inner pieces 112a to 112d are moved outwardly in the radial direction of the out die 110 to be separated from each other, they are located between each other in a front view as viewed from the front end side. A cross-shaped space 118 is formed. By the resin composition discharged from the space 118, a suction pipe part 2 and a cross-shaped partition part 12 of the connecting pipe part 3 in the drain tube 1 described later are formed.

The size of the inner pieces 112a to 112d of the first indies 112 is not particularly limited, and may be appropriately designed according to the sizes of the outer wall 10 and the partition portion 12 of the drain tube 1 to be manufactured.
The mechanism for moving the inner pieces 112a to 112d in the out die 110 in the radial direction of the out die 110 is not particularly limited, and a known mechanism employed when moving a member in the mold, such as air drive or servo drive, is adopted. can do.

  The second indie 114 includes four front end pieces 114a to 114d at positions corresponding to the inner pieces 112a to 112d of the first indie 112, respectively, when viewed from the front end side. The distal end piece 114a corresponds to the inner piece 112a, and the distal end piece 114b corresponds to the inner piece 112b. The distal end piece 114c corresponds to the inner piece 112c, and the distal end piece 114d corresponds to the inner piece 112d.

The four front end pieces 114 a to 114 d are columnar members extending in the radial direction of the out die 110. In this example, the front end pieces 114 a to 114 d are narrower on the front end side than the rear end side in a front view as viewed from the front end side of the out die 110. The four tip side pieces 114 a to 114 d are provided on the tip side of the out die 110 so that the side surfaces of the tip side pieces 114 a to 114 d are in contact with the tip of the out die 110.
Each of the four front end pieces 114 a to 114 d is configured to move in the radial direction of the out die 110 while being in contact with the front end of the out die 110.

When the distal end side pieces 114a to 114d are moved inward in the radial direction of the out die 110, the distal end portions of the distal end side pieces 114a to 114d come into contact with the inner pieces 112a to 112d of the first indie 112, respectively. Yes.
As shown in FIG. 2, with the inner pieces 112 a to 112 d of the first indies 112 being spaced apart from each other, the tip side pieces 114 a to 114 d are changed to the diameter of the out die 110 until the tip portions contact the inner pieces 112 a to 112 d. It can be moved inside the direction. By discharging the resin composition from the extrusion mold 100 in this state, the outer wall 10 in which the slits 18 are formed is formed.

The shape and size of the tip side pieces 114a to 114d of the second indie 114 are not particularly limited, and may be appropriately designed according to the shape and width of the slit 18 formed in the outer diameter 10 of the drain tube 1 to be manufactured.
The mechanism for moving the distal end pieces 114a to 114d in the radial direction of the out die 110 on the distal end side of the out die 110 is not particularly limited, and is a known mechanism that is employed when moving a member in a mold such as air drive or servo drive. A mechanism can be employed.

(Extruder)
The extruder supplies the resin composition from the rear end side to the front end side to the extrusion mold. It does not specifically limit as an extruder, A well-known extruder can be employ | adopted.
A gear pump may be provided between the extrusion mold and the extruder. Thereby, the supply amount of the resin composition from the extruder to the extrusion mold can be easily controlled.
The gear pump is not particularly limited, and a known gear pump can be employed.

(Drain tube)
Hereinafter, the drain tube 1 manufactured by a tube manufacturing apparatus including the above-described extrusion mold 100 will be described.
As shown in FIG. 4, the drain tube 1 is a resin tube in which the suction tube portion 2, the connecting tube portion 3, and the outflow tube portion 4 are integrally formed in order from the tip 1 a. The suction pipe part 2, the connecting pipe part 3 and the outflow pipe part 4 are provided with a cylindrical outer wall 10 having flexibility, and a flow path leading from the front end 1a to the rear end 1b is formed inside the outer wall 10. Yes.

The outer diameter of the drain tube 1 is not particularly limited, and can be appropriately set depending on the application.
The thickness of the outer wall 10 is appropriately set according to the outer diameter, material, etc. of the drain tube 1 in consideration of the flexibility of the drain tube 1, the difficulty of being crushed when inserted into the body, the difficulty of breaking during the milking operation, and the like. it can.

  As shown in FIGS. 4 to 7, a partition portion 12 extending from the front end 1 a to the rear end 3 a of the connection tube portion 3 is provided in the suction tube portion 2 and the connection tube portion 3. The partition portion 12 includes a rod-shaped core portion 14 extending along the central axis inside the suction tube portion 2 and the connection tube portion 3, and extends from the core portion 14 to the inner surface of the outer wall 10, and the suction tube portion 2 and the connection tube portion. Four strip-shaped partition plates 16 formed to extend in the three axial directions.

The four partition plates 16 are formed radially from the core portion 14 at intervals of 90 degrees around the axis in a cross section cut in a direction perpendicular to the axial direction of the drain tube 1. Thereby, four flow paths 20 partitioned around the central axis by the partitioning portion 12 are formed inside the suction tube portion 2 and the connecting tube portion 3. The four flow paths 20 formed inside the suction pipe section 2 and the connection pipe section 3 merge at the boundary portion between the connection pipe section 3 and the outflow pipe section 4, and become one flow path 22 in the outflow pipe section 4. It has become.
The thickness of the partition plate 16 is not particularly limited, and can be appropriately set in consideration of the width of the flow path partitioned by the partition plate, the difficulty of crushing the suction tube portion and the connecting tube portion when inserted into the body, and the like.

  Four slits 18 extending along each of the four flow paths 20 partitioned by the partition portion 12 are formed in the outer wall 10 of the suction tube portion 2 from the tip 1a to the rear end 2a of the suction tube portion 2. . That is, a slit 18 extending from the front end 1 a to the rear end 2 a of the suction tube portion 2 is formed at a position corresponding to each of the four flow paths 20 on the outer wall 10 of the suction tube portion 2.

Since the slit 18 is formed in the outer wall 10 of the suction tube portion 2, body fluid can be sucked into the flow path 20 from the outer peripheral portion of the suction tube portion 2 through the slit 18. In addition, even when the suction tube part 2 is placed in the body, even if the body tissue grows so as to enter the slit 18, the body tissue moves along the slit 18 when the suction tube part 2 is pulled out of the body. Move to 1a and exit. Therefore, it is possible to prevent the body tissue that has entered the slit 18 from being torn when the suction tube portion 2 is pulled out of the body.
The width of the slit 18 can be appropriately determined according to the outer diameter of the drain tube, taking into account the outer diameter of the suction tube portion, the amount of body fluid sucked, and the like.

  When the drain tube 1 is used, the suction tube portion 2 and the connecting tube portion 3 are inserted into the body, the suction tube portion 2 is left in the affected area, and the rear end side portion of the outflow tube portion 4 is taken out of the body. Connect to a suction machine. By aspirating with a suction machine or the like in this state, blood or the like accumulated in the affected area enters the flow path 20 from the slit 18 portion of the drain tube 1 and is discharged out of the body through the connecting pipe section 3 and the outflow pipe section 4.

(Drain tube manufacturing method)
In the tube manufacturing apparatus including the extrusion mold 100, the first in-die 112 and the second in-die 114 are moved in the radial direction of the out-die 110 while continuously supplying the resin composition to the extrusion mold 100. By doing so, the suction tube portion 2, the connecting tube portion 3, and the outflow tube portion 4 can be integrally extruded to obtain the drain tube 1.

  Specifically, as shown in FIG. 2, the four inner pieces 112 a to 112 d of the first indie 112 are moved to the outside in the radial direction of the out die 110, and the inner pieces 112 a to 112 d are all separated from the out die 110. And the inner pieces 112a to 112d are separated from each other. At this time, an annular space 116 is formed between the out die 110 and the four inner pieces 112a to 112d in a front view as viewed from the front end side, and a cross shape is formed between the inner pieces 112a to 112d. Space 118 is formed. Further, the tip side pieces 114a to 114d of the second indie 114 are moved inward in the radial direction of the out die 110 until their tip portions come into contact with the inner pieces 112a to 112d, respectively. As a result, when the extrusion mold 100 is viewed from the front end side, the annular space 116 is partially blocked by the front end side pieces 114 a to 114 d of the second die 114.

  In this state, the resin composition is supplied from the extruder to the extrusion mold 100 from the rear end side to the front end side. The supplied resin composition is discharged from the tip of the extrusion mold 100 into the shape of the suction tube portion 2. The outer wall 10 is formed by the resin composition discharged from the annular space 116 in the out die 110, and the slit 18 is formed at a position corresponding to the tip side pieces 114 a to 114 d of the second indie 114 in the outer wall 10. Moreover, the partition part 12 is formed with the resin composition discharged from the cross-shaped space 118 formed between the inner pieces 112a to 112d.

  Next, as shown in FIG. 3, while supplying the resin composition to the extrusion mold 100, the tip-side pieces 114 a to 114 d of the second indies 114 are placed outside in the radial direction of the out-die 110, and an annular space. Move to outside 116. Then, the annular space 116 is not obstructed by the tip-side pieces 114a to 114d when the extrusion mold 100 is viewed from the tip side. At this time, the four inner pieces 112a to 112d of the first indie 112 are kept separated from each other. In this state, the resin composition supplied to the extrusion mold 100 is discharged from the tip of the extrusion mold 100 into the shape of the connecting pipe portion 3.

  Next, as shown in FIG. 1, while supplying the resin composition to the extrusion mold 100, the inner pieces 112 a to 112 d of the first indies 112 are moved to the inner side in the radial direction of the out dies 110, respectively. Adhere closely so as not to form a gap between them. In this state, the resin composition supplied to the extrusion mold 100 is discharged from the tip of the extrusion mold 100 into the shape of the outflow pipe portion 4. Thereby, the drain tube 1 in which the suction pipe part 2, the connecting pipe part 3, and the outflow pipe part 4 are integrally formed is obtained.

  Silicone rubber is preferably used as the resin composition for forming the drain tube. Silicone rubber is softer than soft polyurethane or the like. Therefore, by forming the drain tube with silicone rubber, it becomes easy to place the suction tube portion at a target position in the body.

  You may mix | blend a contrast agent with the resin composition which forms a drain tube. As a result, the drain tube can be imaged using X-rays. In particular, it is preferable that the contrast medium is blended in the suction tube portion and the connection tube portion, which are portions inserted into the body in the drain tube. As a result, it is possible to confirm whether or not the suction tube portion is placed at a target position in the body. Moreover, even if the suction pipe part and the connecting pipe part are broken at the time of pulling out the tube, since the cut portion existing in the body can be confirmed, it is possible to prevent the tube from being unexpectedly left in the body.

As a contrast agent, a publicly known thing can be used, for example, barium sulfate, titanium oxide, etc. are mentioned.
As the contrast agent, one kind may be used alone, or two or more kinds may be used in combination.

The greater the amount of contrast agent added to the drain tube, the lower the strength of the drain tube and the more likely it will break, and the easier it will collapse when inserted into the body. Therefore, when a contrast agent is blended in the drain tube, it is preferable that the contrast agent is partially blended in a specific portion of the drain tube.
Specifically, for example, in the case of the drain tube 1, the contrast agent can be blended into one of the four partition plates 16 in the partition portion 12 from the front end to the rear end. In addition, a contrast agent can be blended in a part of the thickness of the suction pipe part 2, the connecting pipe part 3, and the outflow pipe part 4.

An example of a drain tube containing a contrast agent is the drain tube 1A illustrated in FIG. The same parts in FIG. 10 as FIG. 6 and FIG. The drain tube 1A is the same as the drain tube 1 except that a contrast line 40 containing a contrast agent is formed.
As shown in FIGS. 10A to 10D, the contrast line 40 is formed from the front end to the rear end of the drain tube 1A. Further, as shown in FIGS. 10B and 10C, in the cross section perpendicular to the length direction of the suction tube portion 2 and the connecting tube portion 3, the contrast line 40 includes four partitions of the partition portion 12. It is formed from the radial intermediate portion of one of the plates 16 to the outer wall 10.

  The extrusion mold and tube manufacturing apparatus according to the present invention described above is not an excessively complicated configuration but is simple, and the suction tube portion, the connecting tube portion, and the outflow tube portion are easily integrally extruded to form a drain tube. Can be manufactured.

The extrusion mold and tube manufacturing apparatus of the present invention are not limited to the above-described extrusion mold 100 and the tube manufacturing apparatus provided with the extrusion mold 100.
For example, the extrusion mold of the present invention is not limited to the one that produces a drain tube having a circular cross section. For example, an extrusion mold for manufacturing a drain tube having an elliptical cross section may be used.

Specifically, the extrusion mold 200 of the present invention may be the extrusion mold 200 illustrated in FIG.
The extrusion molding die 200 is provided on a cylindrical out die 210, a first in-die 212 provided in the out die 210 so that the tip is aligned with the tip of the out die 210, and the tip side of the out die 210. The second indie 214 is provided.

The out die 210 is the same as the out die 110 except that it has an elliptical cylindrical shape.
The cross-sectional shape perpendicular to the length direction of the hollow portion in the out die 210 is an elliptical shape. The shape of the out die 210 in this example is an elliptic cylinder, but the out die does not have to be an elliptic cylinder, and if the cross-sectional shape of the hollow portion is a predetermined shape such as an ellipse, The shape may be a rectangular parallelepiped.

The first in-die 212 is a first inner piece 212a and a second inner piece 212b that move in the short-diameter direction of the out-die 210, and an outer side of both the long-diameter direction of the out-die 210 in the first inner piece 212a and the second inner piece 212b. And a third inner piece 212c and a fourth inner piece 212d that move in the major axis direction.
The first inner piece 212 a to the fourth inner piece 212 d are columnar members that extend in the axial direction of the out die 210. The positions of the tips of the first inner piece 212 a to the fourth inner piece 212 d in the axial direction of the out die 210 are aligned with the tips of the out die 210.

  The front view shape seen from the front end side of the first inner piece 212a is a shape in which the side far from the second inner piece 212b in the rectangle is a convex arc shape toward the outer side. The front view shape seen from the front end side of the second inner piece 212b is a shape in which a side far from the first inner piece 212a in a rectangle is a convex arc shape toward the outer side. The third inner piece 212c and the fourth inner piece 212d have a semicircular shape in which the sides close to the first inner piece 212a and the second inner piece 212b are linearly cut out.

The first inner piece 212a to the fourth inner piece 212d are provided around the central axis of the out die 210 in a front view when the first indie 212 is viewed from the front end side. As shown to FIG. 8 (A), the 1st inner piece 212a and the 2nd inner piece 212b can be closely_contact | adhered, without forming a clearance gap between mutual opposing surfaces. Further, the third inner piece 212c and the fourth inner piece 212d are formed on both sides of the first inner piece 212a and the second inner piece 212b in a state in which the opposing surfaces are in close contact with each other without a gap therebetween. It can be adhered.
In this example, when the four first inner pieces 212a to the fourth inner piece 212d are brought into close contact with each other without a gap therebetween, the front view shape viewed from the front end side becomes an ellipse. At this time, an elliptical annular space 216 is formed between the out die 210 and the first indie 212 when viewed from the front end side.

  The four first inner pieces 212 a to the fourth inner piece 212 d in the first in-die 212 are configured to move in the radial direction of the out-die 210. Specifically, the first inner piece 212a and the second inner piece 212b move in the minor axis direction of the out die 210, and the third inner piece 212c and the fourth inner piece 212d move in the major axis direction of the out die 210. ing.

  As shown in FIG. 8 (B), when the first inner piece 212a to the fourth inner piece 212d are moved to the outside in the radial direction of the out die 210 and separated from each other, in the front view seen from the front end side, A space 218 extending linearly in the major axis direction is formed between the first inner piece 212a and the second inner piece 212b. On the third inner piece 212c side of the space 218, a space 220 linearly extending in the minor axis direction is formed between the first inner piece 212a and the second inner piece 212b and the third inner piece 212c. Similarly, on the fourth inner piece 212d side of the space 218, a space 222 linearly extending in the minor axis direction is formed between the first inner piece 212a and the second inner piece 212d.

  The second indie 214 includes four tip end pieces 214a to 214d at positions corresponding to the first inner piece 212a to the fourth inner piece 212d of the first indie 212, respectively, when viewed from the front end side. . The distal end piece 214a corresponds to the first inner piece 212a, and the distal end piece 214b corresponds to the second inner piece 212b. The distal end piece 214c corresponds to the third inner piece 212c, and the distal end piece 214d corresponds to the fourth inner piece 212d.

The four front end pieces 214 a to 214 d are columnar members extending in the radial direction of the out die 210. In this example, the front end pieces 214a to 214d are narrower on the front end side than the rear end side when viewed from the front end side of the out die 210. The four front end pieces 214 a to 214 d are provided on the front end side of the out die 210 so that their side surfaces are in contact with the front end of the out die 210.
Each of the four tip side pieces 214 a to 214 d is configured to move in the radial direction of the out die 210 while being in contact with the tip of the out die 110.

  As shown in FIG. 8B, when the distal end pieces 214 a to 214 d are moved inward in the radial direction of the out die 110, the distal ends of the distal end pieces 214 a to 214 d are the first indies 112. The inner piece 212a to the fourth inner piece 212d are in contact with each other.

In the tube manufacturing apparatus including the extrusion mold 200, the first in-die 212 and the second in-die 214 are moved in the radial direction of the out-die 210 while continuously supplying the resin composition to the extrusion mold 200. By doing so, the drain tube 1A illustrated in FIG. 9 can be manufactured. The same parts in FIG. 9 as those in FIG.
The drain tube 1A includes an elliptical cylindrical outer wall 10A instead of the cylindrical outer wall 10, and the drain tube 1 and the connection tube portion 3 are provided with a partition portion 12A instead of the partition portion 12, The same.

  The partition portion 12A includes three strip-shaped first partition plates 24, second partition plates 26, and third partition plates 28 that extend from the front end of the drain tube 1A to the rear end of the connecting tube portion 3. As shown in FIGS. 9 (A) and 9 (B), the first partition plate 24 and the second partition plate 26 extend in the short-diameter direction near the leading ends of both the long-diameter directions of the outer wall 10A and extend inside the outer wall 10A. It is provided to partition. The third partition plate 28 extends so as to connect the intermediate portions in the length direction of the first partition plate 24 and the second partition plate 26, and between the first partition plate 24 and the second partition plate 26 in the outer wall 10A. It is provided to partition.

  Inside the suction pipe part 2 and the connecting pipe part 3, four flow paths 20A partitioned around the central axis by the partition part 12A are formed. The four flow paths 20A formed inside the suction pipe part 2 and the connection pipe part 3 merge at the boundary portion between the connection pipe part 3 and the outflow pipe part 4, and as shown in FIG. One flow path 22 </ b> A is formed in the portion 4.

  As shown in FIG. 9A, on the outer wall 10A of the suction tube portion 2, four slits 18 extending along each of the four flow paths 20A partitioned by the partition portion 12A are provided from the tip to the suction tube portion 2. It is formed up to the rear end. That is, a slit 18 extending from the front end to the rear end of the suction tube portion 2 is formed in the outer wall 10A of the suction tube portion 2 at a position corresponding to each of the four flow paths 20A.

  In the manufacture of the drain tube 1A using the extrusion mold 200, first, as shown in FIG. 8B, the four first inner pieces 212a to the fourth inner piece 212d of the first indies 212 are respectively out. Move to the outside of the die 210 in the radial direction. The first inner piece 212a to the fourth inner piece 212d are all separated from the out die 210, and the first inner piece 212a to the fourth inner piece 212d are separated from each other. At this time, an elliptical annular space 216 is formed between the out die 210 and the first inner piece 212a to the fourth inner piece 212d when viewed from the front end side. Further, between the first inner piece 212a to the fourth inner piece 212d, a space 218 that linearly extends in the major axis direction, and a space 220 that linearly extends in the minor axis direction on both sides of the major axis direction of the space 218, 222 is formed. Further, the distal end pieces 214a to 214d of the second indie 214 are moved inward in the radial direction of the out die 210 until their distal end portions come into contact with the first inner piece 212a to the fourth inner piece 212d, respectively. . As a result, when the extrusion mold 200 is viewed from the front end side, the elliptical annular space 216 is partially blocked by the front end side pieces 214a to 214d of the second die 214.

  In this state, the resin composition is supplied from the extruder to the extrusion mold 200 from the rear end side toward the front end side. The supplied resin composition is discharged from the tip of the extrusion molding die 200 into the shape of the suction tube portion 2 of the drain tube 1A shown in FIG. The outer wall 10A is formed by the resin composition discharged from the annular space 216 in the out die 210, and the slit 18 is formed at a position corresponding to the tip side pieces 214a to 214d of the second indie 214 in the outer wall 10A. Further, the partition portion 12A is formed by the resin composition discharged from the spaces 218, 220, and 222 formed between the first inner piece 212a to the fourth inner piece 212d.

  Next, as shown in FIG. 8C, while supplying the resin composition to the extrusion mold 200, the tip side pieces 214 a to 214 d of the second die 214 are placed on the outer side in the radial direction of the out die 210. Move to outside of annular space 216. Then, when the extrusion molding die 200 is viewed from the front end side, the elliptical annular space 216 is not obstructed by the front end pieces 214a to 214d. At this time, the first inner piece 212a to the fourth inner piece 212d of the first indie 212 are kept separated from each other. In this state, the resin composition supplied to the extrusion mold 200 is discharged from the tip of the extrusion mold 100 into the shape of the connecting pipe portion 3 of the drain tube 1A shown in FIG.

  Next, as shown in FIG. 8A, while supplying the resin composition to the extrusion mold 200, the first inner piece 212a to the fourth inner piece 212d of the first indie 212 are each changed to the diameter of the out die 210. Move to the inside of the direction and make sure that there is no gap between them. In this state, the resin composition supplied to the extrusion mold 200 is discharged from the tip of the extrusion mold 100 into the shape of the outflow pipe portion 4 of the drain tube 1A shown in FIG. Thereby, the drain tube 1A in which the suction pipe part 2, the connection pipe part 3, and the outflow pipe part 4 are integrally formed is obtained.

In the extrusion mold of the present invention, the number of inner pieces of the first indies is not limited to four. Specifically, in the extrusion mold of the present invention, the three inner pieces of the same shape having a fan shape with a central angle of 120 degrees when viewed from the front end side have a circular cross-sectional shape of the hollow portion. An extrusion mold provided with a first in-die provided around the center axis of the out-die may be used. If this extrusion mold is used, a drain tube having a suction pipe part and a connecting pipe part in which three partition plates are radially formed at intervals of 120 degrees around the central axis from the core part can be obtained.
In addition, the extrusion mold of the present invention is an out die whose five inner pieces having the same fan shape with a central angle of 72 degrees when viewed from the front end side have a circular cross section. It may be an extrusion mold provided with a first indie provided around the central axis. If this extrusion mold is used, a drain tube having a suction tube portion and a connecting tube portion in which five partition plates are radially formed at intervals of 72 degrees around the central axis from the core portion is obtained.
Moreover, when it is set as the 1st indie which combined the fan-shaped inner piece in front view shape in this way, the front view shape of each of these inner pieces may differ. For example, for extrusion molding including a first in-die comprising a combination of two inner pieces having a fan shape with a central angle of 120 degrees and a fan shape having a central angle of 60 degrees. It may be a mold.

  The number of the tip side pieces of the second indies in the extrusion mold of the present invention is not limited to four. Moreover, the number of the tip side pieces of the second indies may be the same as or different from the number of the inner pieces of the first indies. Specifically, the extrusion mold of the present invention may be, for example, an extrusion mold that includes the second indies having three tip-side pieces 114a in the extrusion mold 100. If the extrusion mold is used, a drain tube in which three slits corresponding to three of the four flow paths formed in the suction pipe portion are formed on the outer wall can be obtained.

DESCRIPTION OF SYMBOLS 1, 1A Drain tube 10, 10A outer wall 12 Partition part 14 Core part 16 Partition plate 18 Slit 20, 20A, 22, 22A Flow path 24 1st partition plate 26 2nd partition plate 28 3rd partition plate 100, 200 For extrusion molding Die 110, 210 Out die 112, 212 First indie 112a-112d Inner piece 114, 214 Second indie 114a-114d, 214a-214d Tip side piece 116, 118 Space 212a First inner piece 212b Second inner piece 212c First 3 inner piece 212d fourth inner piece 216, 218, 220, 222 space

Claims (3)

A method for producing a drain tube using a tube production apparatus comprising an extrusion mold and an extruder for supplying a resin composition to the extrusion mold,
The extrusion mold is provided on a cylindrical out die, a first in die provided in the out die so that a tip is aligned with a tip of the out die, and a tip side of the out die. A second indie,
The first indie is provided around a central axis of the out die, and includes a plurality of inner pieces that move in a radial direction of the out die,
In a front view seen from the front end side, when the plurality of inner pieces are brought into close contact with each other, an annular space is formed between the out die and the first in die,
Said second Indaisu is provided in contact with the previous SL-out die moves in the radial direction of the out-die comprises a plurality of tip end piece of the columnar extending in a radial direction of the out-die,
When the plurality of tip side pieces are moved inward in the radial direction, the tip side on the tip side is such that the tip ends on the inside in the radial direction of the tip side pieces are in contact with the tips of the plurality of inner pieces. When viewed from the front, each of the tip side piece and the inner piece are arranged corresponding to each other,
While continuously supplying the resin composition from the extruder to the mold for extrusion, the first in-die and the second in-die are moved in the radial direction of the out-die to obtain a drain tube. A method for producing a drain tube. The cross-sectional shape perpendicular to the length direction of the hollow portion in the out die is a circular shape,
The first indie includes four inner pieces having a fan shape with a central angle of 90 degrees when viewed from the front end side, and when the four inner pieces are brought into close contact with each other, the out die and the first die An annular space is formed between the indies,
The method for manufacturing a drain tube according to claim 1, wherein the second indie includes four tip side pieces corresponding to the inner piece in a front view as viewed from the tip side. The cross-sectional shape perpendicular to the length direction of the hollow portion in the out die is an elliptical shape,
The first indie has a long diameter outside both the first inner piece and the second inner piece moving in the short diameter direction of the out die, and the long diameter direction of the out die in the first inner piece and the second inner piece. A third inner piece and a fourth inner piece moving in the direction,
When viewed from the front end side, when the four inner pieces are brought into close contact with each other, an elliptical annular space is formed between the out die and the first in die,
The method for manufacturing a drain tube according to claim 1, wherein the second indie includes four tip-side pieces corresponding to the four inner pieces in a front view as viewed from the tip side.

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