JP2016000484A - Method for producing outer shape-deformed drain tube, crosshead die, and crosshead type extruder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an outer shape-deformed drain tube, the flexibility and mechanical strength of which are hardly changed in the axial direction, and to provide a production method of the outer shape-deformed drain tube, a crosshead die, and a crosshead type extruder.SOLUTION: The crosshead die is used for extrusion-molding the outer shape-deformed drain tube including a tubular part and a drain part flatter than the tubular part and includes: an out die 8 having an out die main body 15, which has a through-hole 15a, and a movable out die 16 arranged on the discharge-side surface of the out die main body 15 so that they can be separated from each other; and an inner die 9 having a fixed inner die 11, the tip of which is fixed on the inside of a discharge hole 5, and a movable inner die 12 supported so as to be moved forward or backward with respect to the fixed inner die 11. The crosshead type extruder includes the crosshead die. The production method of the outer shape-deformed drain tube comprises a step of performing extrusion molding by moving the movable inner die 12 and the movable out die 16 attachably to/detachably from each other and forward/backward with respect to each other according to shapes of the tubular part and the drain part.

Description

  The present invention relates to a method for manufacturing an externally deformed drain tube, a crosshead die and a crosshead type extruder, and more specifically, a method for manufacturing an externally deformed drain tube having a small change in flexibility and mechanical strength in the axial direction, and The present invention relates to a crosshead die and a crosshead type extruder used in the manufacturing method.

For excretion of wounds after surgery, blood accumulated inside, body fluid (exudate, etc.), or urine etc. (referred to as body fluid in the present invention) during treatment in an intensive care unit, etc. A drain tube is used.
There are many types of medical drain tubes. For example, a drain tube having a uniform cross-sectional shape perpendicular to the axial direction, a so-called “multi-slit drain tube”, a so-called “externally deformed drain tube”, and the like can be given.
The “multi-slit drain tube” is, for example, a tubular portion having an axial hole on one end side of a tube having a drain portion having at least two fluid passages (referred to as opening fluid passages) opened on the outer peripheral surface along the axial direction. In the other end side of the tube (see, for example, Patent Document 1).
The “outer shape modified drain tube” is, for example, a tube having a tubular portion having a substantially circular cross section on one end side in the axial direction and a flat drain portion having an elliptical shape or a rectangular cross section on the other end side (for example, , See Patent Document 2). This externally deformed drain tube is preferably used when it is necessary to discharge foreign matters such as thrombus in addition to body fluid.

Among such medical drain tubes, multi-slit drain tubes and externally deformed drain tubes having different end shapes are usually connected by connecting the drain portion and the tubular portion together with a flexible tubular collar. (For example, see FIG. 6 of Patent Document 1).
When a medical drain tube is formed using a tubular member in this way, the outer diameter in the vicinity of the connecting portion between the drain portion and the tubular portion is increased by the tubular collar, and the flexibility in the vicinity of the connecting portion is reduced, and the strength is reduced. Get higher. Since the medical drain tube is temporarily embedded and indwelled in the patient's body and finally removed from the body, if there is a connection as described above, the surgical operation at the time of implantation and removal This complicates the burden on patients. Therefore, development of the medical drain tube which does not have a connection part is desired.

In order to meet this demand, it is conceivable to integrally form a medical drain tube that does not have a tubular collar connection by extrusion molding. That is, if the shape of the molded body is changed during extrusion molding and subsequently extrusion molding is performed, an integrally formed tube having no connection portion can be manufactured.
Several dies have been proposed for use in changing the shape of the molded body during such extrusion. For example, Patent Document 3 describes a cross-sectional shape-variable extrusion die mechanism that moves the indie in a direction perpendicular to the resin flow to change the number of lumens of the tube. Patent Document 4 describes a cross-sectional shape variable extrusion die mechanism that changes the shape of the number of lumens of a molded product by moving the indie back and forth in the longitudinal direction (vertical direction of the indie). Further, Patent Document 5 describes a method of changing the cross-sectional shape of the extruded material by displacing the flow path regulating block in the base.

Japanese Examined Patent Publication No. 2-17185 Registered Utility Model No. 3168148 Japanese Patent No. 3310586 Japanese Patent No. 3418535 JP 2005-219254 A

Thus, according to Patent Document 3 and Patent Document 4, a tube with a changed number of lumens can be formed, and according to Patent Document 5, an extruded product with a changed cross-sectional shape can be formed.
However, none of the die mechanisms and methods described in these patent documents can form an outer shape-transformed drain tube whose outer shape and inner shape are changed. It is also difficult to form an externally deformed drain tube that is required to have a small change in flexibility and mechanical strength in the axial direction in terms of functionality and handling.

  Accordingly, the present invention provides an externally deformed drain tube having a small change in flexibility and mechanical strength in the axial direction, preferably having a small number of parts, a manufacturing method thereof, a crosshead die used in the manufacturing method, and An object is to provide a crosshead extruder.

The object of the present invention has been achieved by the following means.
(1) A crosshead type extruder for continuously extruding an externally deformed drain tube comprising a tubular part having a shaft hole and a drain part connected to the tubular part and flatter than the tubular part. A crosshead die,
It has an out die having a discharge hole, and an inner die arranged in the discharge hole,
The out die has an out die body having a through hole, and a set of movable out dies disposed on the discharge side surface of the out die body so as to be close to and away from each other.
The inner die is a crosshead die having a fixed inner die whose tip is fixed in the discharge hole, and a movable inner die supported so as to be able to move forward and backward relative to the fixed inner die.
(2) The crosshead die according to (1), wherein the movable inner die is supported so as to be able to move forward and backward in the circumferential outer side of the fixed inner die.
(3) The crosshead die according to (1) or (2), wherein the movable out die is attached to the discharge side surface by screwing.
(4) The crosshead die according to any one of (1) to (3), wherein the movable out die is configured by a pair of divided bodies having an inner surface with an arc-shaped cross section.
(5) A crosshead type extruder comprising the crosshead die according to any one of (1) to (4).
(6) A crosshead type extruder according to (5), wherein an externally deformed drain tube comprising a tubular part having an axial hole and a drain part connected to the tubular part and flatter than the tubular part is provided. A manufacturing method for manufacturing using
According to the tubular part and the drain part, the inner die is moved forward and backward, and the outer deformed drain tube is manufactured by extrusion molding with the movable out die approaching or separating.
(7) The movable out die is brought close to and integrated, the movable inner die is retracted from the discharge hole, the tubular portion is formed, the movable out die is separated, and the movable inner die is discharged. The method of manufacturing a medical drain tube according to (6), wherein the step of advancing into the hole and forming the drain portion is continuously performed in this order or in the reverse order.
(8) The method for producing a medical drain tube according to (6) or (7), wherein a thermosetting silicone rubber composition is extruded.

The crosshead die of the present invention and the crosshead extruder of the present invention include the above-mentioned out die and inner die, and can integrally mold an externally deformed drain tube having a tubular portion and a drain portion. Therefore, by the method for producing an externally deformed drain tube of the present invention using the crosshead type extruder of the present invention, an externally deformed drain tube having a small change in flexibility and mechanical strength in the axial direction can be manufactured. Furthermore, the externally deformed drain tube can be formed with a smaller number of parts.
Therefore, the externally deformed drain tube manufactured by the manufacturing method of the externally deformed drain tube of the present invention is excellent in functionality and handleability, and is suitably used as an externally deformed drain tube for medical use.

FIG. 1 is a view showing an example of an externally deformed drain tube manufactured by the manufacturing method of an externally deformed drain tube of the present invention. FIG. 2 is a partially enlarged view in the vicinity of the crosshead die showing an example of the crosshead extruder of the present invention. FIG. 3 is an explanatory view for explaining the arrangement state of the crosshead die in a preferred example of the manufacturing method of the externally deformed drain tube of the present invention.

  An outer shape deformed drain tube manufactured by the method for manufacturing an outer shape deformed drain tube of the present invention will be described. As described above, the externally deformed drain tube has a tubular portion having a substantially circular cross section (also referred to as a tubular discharge portion) and a flat drain portion (tubular liquid collecting portion), which are integrally formed, that is, a connecting member. Etc. without being connected. You may have the transition part which cross-sectional shape transfers to a flat shape from a substantially circular shape between a tubular discharge part and a tubular liquid collection part.

  The externally deformed drain tube of the present invention may be any tube as long as the tubular discharge portion and the tubular liquid collection portion are integrally connected, and examples include those conventionally known, for example, those described in Patent Document 2. The shape and dimensions of the externally deformed drain tube are not particularly limited, and are appropriately set according to the usage mode and standards. For example, if an example of a dimension is given, a tubular discharge part will be set in the range of 3-10 mm, and the outer diameter of a tubular liquid collection part will be set in the range of 3-10 mm.

The externally deformed drain tube manufactured by the externally deformed drain tube manufacturing method of the present invention is small in changes in flexibility and mechanical strength.
The flexibility can be confirmed at the rate of change in the axial direction by the bending radii of the drain part, the transition part, and the tubular part. Specifically, the ratio (%) of the bending radius of the drain part and the annular part to the bending radius of the transition part is obtained. In the present invention, the small change in flexibility means that this ratio is preferably 60% or more, more preferably a value close to 100%. The bending radius means the minimum bending radius that does not close the inner hole when the drain portion or the like is bent.
The mechanical strength can be confirmed at the rate of change in the axial direction based on the strength of the drain portion alone, the strength of the drain portion and the transition portion, the strength of the transition portion and the tubular portion, and the tensile strength of the tubular portion. Specifically, the respective ratios obtained by dividing the tensile strength of the drain portion and the transition portion by the tensile strength of the drain portion and the tensile strength of the tubular portion are obtained. In the present invention, the phrase “the change in mechanical strength is small” means that the ratio is preferably 90% or more, more preferably a value close to 100%.

  Hereinafter, a preferred externally deformed drain tube manufactured by the method of manufacturing an externally deformed drain tube of the present invention will be briefly described.

As shown in FIG. 1, the preferred externally deformed drain tube 21 is formed by integrally connecting a tubular portion 22, a transition portion 23, and a drain portion 24 along the axial direction.
Here, FIG. 1A is a side view showing a side surface of a preferred outer shape-transformed drain tube, and FIG. 1B is a top view showing an upper surface of the preferred shape-transformed drain tube, and FIG. FIG. 1 is a cross-sectional view showing a cross section of a tubular portion of a preferred outer shape-deformed drain tube, and FIG. 1D is a cross-sectional view showing a cross section of a drain portion of the preferred outer shape-deformed drain tube.
Note that the externally deformed drain tube shown in FIG. 1 is a schematic view for facilitating understanding of the present invention, and the size or relative size relationship of each member may be changed for convenience of explanation. Yes, it does not show the actual relationship as it is.

  The tubular portion 22 is not embedded or placed in the patient's body, but has a free end connected to a suction device or the like to transfer and discharge the collected body fluid or the like. The tubular portion 22 only needs to have a normal tubular structure, and is a tubular body having an axial hole 22a along the axial direction. Further, the tubular portion 22 has a substantially circular cross section perpendicular to the axis. Accordingly, the tubular portion 22 is formed by a tubular wall 22b having a ring-shaped cross section perpendicular to the axial direction.

  The drain unit 24 has a function of being embedded and indwelled in the patient's body, collecting body fluid, etc., and transporting it outside the body. This drain part 24 usually has a flat tubular structure and collects coagulated blood and the like. As shown in FIG. 1, the cross section perpendicular to the axial direction is substantially elliptical, and the tubular body has a substantially elliptical axial hole 24a along the axial direction. Therefore, the drain portion 24 is formed by a tubular wall 24b having a substantially elliptical cross section perpendicular to the axial direction.

  The transition part 23 connects the tubular part 22 and the drain part 24, and a part on the drain part 24 side may be embedded and indwelled in the patient's body. Therefore, the transition portion 23 has a cross section perpendicular to the axial direction changed from a substantially circular shape to a substantially elliptical shape.

Thus, the outer shape and inner shape of the outer shape deformed drain tube 21 changes from a substantially circular shape to a substantially elliptic shape along the axial direction.
The externally deformed drain tube 21 having such a configuration collects body fluid and the like at the drain part 24 and discharges it outside the body via the transition part 23 and the tubular part 22.

  The preferred outer shape deformed drain tube 21 has been described above, but the outer shape deformed drain tube manufactured by the method for producing an outer shape deformed drain tube of the present invention is not limited to the preferred outer shape deformed drain tube 21.

  As long as the crosshead type extruder of the present invention includes the crosshead die of the present invention, other structures and the like are not particularly limited, and known structures and the like can be appropriately employed.

  As shown in FIG. 2, a preferred crosshead extruder 1 of the crosshead extruder of the present invention includes a cylinder (also referred to as a barrel) 2 that houses a screw (not shown), and a drive mechanism that rotates the screw ( (Not shown), an extruder having a supply port (not shown) for charging a molding material into the cylinder 2, and a crosshead die 3 connected to the extruder. The crosshead die 3 is a preferred example of the crosshead die of the present invention that can suitably manufacture the outer shape-transformed drain tube of the present invention.

As described above, the cylinder 2 and the like in this crosshead extruder 1 can be used without any particular limitation, and thus illustration and description thereof are omitted.
For example, the crosshead type extruder may be a single screw extruder or a multi-screw extruder.

  As shown in FIG. 2, the crosshead die 3 includes a crosshead die body 7 having a flow channel cavity 4 of a molding material, an out die 8 mounted on the downstream side of the flow channel cavity 4 and having a discharge hole 5, And an inner die 9 disposed in the crosshead die body 7 and the discharge hole 5.

  As shown in FIG. 2, the inner die 9 has a fixed inner die 11 whose tip is fixed in the discharge hole 5 and a movable inner die 12 supported so as to be able to move forward and backward relative to the fixed inner die 11. doing.

The fixed inner die 11 is a rod-shaped body having a cross-sectional shape corresponding to the inner peripheral surface of the tubular portion 22, and forms a shaft hole 22a. Therefore, in the crosshead die 3, the fixed inner die 11 has a substantially circular cross-sectional shape, but in the present invention, the cross-sectional die is not limited to this as long as it has a cross-sectional shape corresponding to the inner peripheral surface of the tubular portion 22. The distal end portion of the fixed inner die 11 is disposed so as to be substantially flush with the movable out die 16.
The movable inner die 12 is a tubular body having a cross-sectional shape corresponding to the inner peripheral surface of the drain portion 24, and forms a shaft hole 24a. Therefore, in the crosshead die 3, the movable inner die 12 has a substantially elliptical cross-sectional shape. However, in the present invention, the cross-sectional shape is not limited to this as long as the cross-sectional shape corresponds to the inner peripheral surface of the tubular portion 22. . The movable inner die 12 is supported with respect to the fixed inner die 11 so as to be capable of moving back and forth in the axial direction. Thereby, it is possible to move forward and backward on the outer circumferential side of the fixed inner die 11. The movable inner die 12 has a tip that can be disposed in the discharge hole 5 and an end surface that can be disposed substantially flush with the movable out die 16.

  The out die 8 includes an out die main body 15 having a through-hole 15a and a set of movable out dies 16 disposed on the discharge side surface 15b of the out die main body 15 so as to be close to and away from each other. The crosshead die 3 according to the present invention can form the externally deformed drain tube 21 by changing the shape of the discharge hole 5 formed by the inner die 9 and the out die 8. The inner contour of the discharge hole 5 is formed on the outer surface of the inner die 9 as described above. On the other hand, the outer contour of the discharge hole 5 is formed by the inner peripheral surface of the movable out die 16 or by both inner peripheral surfaces of the out die body 15 and the movable out die 16 depending on the arrangement state. The shapes of both inner peripheral surfaces of the out die body 15 and the movable out die 16 are not particularly limited, and an appropriate shape is selected according to the outer shape of the outer shape deformed drain tube to be manufactured.

The out die main body 15 has a plate shape or a disk shape, and has a through hole 15a (see FIG. 3B) penetrating in the thickness direction. The out die body 15 is attached to the crosshead die body 7.
The movable out die 16 is attached to the discharge side surface 15b of the out die main body 15 by screws so as to be close to and away from each other. The movable out die 16 is configured by a pair of divided bodies 16a having an inner surface whose cross-sectional shape is an arc shape (an arc shape obtained by dividing a circular shape into a plurality of portions). The divided body 16a of the movable out die 16 has a substantially circular inner surface as a whole when integrated, and the inner surface together with the out die body 15 becomes a substantially elliptical shape when separated. As described above, the inner peripheral surface of the movable out die 16 is not limited to the above shape.
In the present invention, the movable out die 16 can be approached and separated along one direction perpendicular to the extrusion direction, that is, one of the diametrical directions of the movable out die 16. The movable direction of the movable out die 16 is preferably the horizontal direction or the vertical direction, but is not limited thereto.
As long as the movable out die 16 is movable in the above-described movable direction, the number of the divided bodies 16a is not limited. For example, as a set of divided bodies, two or four divided bodies 16a can be mentioned, and two divided bodies 16a are preferable.
In the crosshead die 3, the movable out die 16 is composed of a semicircular arc-shaped divided body 16a. However, in the present invention, for example, two plates or columns having a semicircular arc cutout may be used. .

  The crosshead die 3 is set to an appropriate size according to the size of the outer shape deformed drain tube to be manufactured.

  The manufacturing method of the externally deformed drain tube of the present invention (hereinafter sometimes referred to as the method of the present invention) is a manufacturing method of manufacturing the externally deformed drain tube using the crosshead type extruder of the present invention. In accordance with the shapes of the tubular portion and the drain portion of the externally deformed drain tube, the inner die is moved back and forth, and the out die is brought into close proximity (integrated) or spaced apart and extruded.

In the method of the present invention, in consideration of the cross-sectional shape of the outer shape deformed drain tube and the shapes of the inner die and the out die, the portion of the discharge hole 5 formed by the inner die and the out die is the portion of the outer shape deformed drain tube to be extruded. That is, the movable inner die and the movable out die are respectively moved so as to coincide with the cross-sectional shapes of the tubular portion and the drain portion.
Therefore, in the method of the present invention, the outer shape-deformed drain tube can be manufactured in the order of the tubular portion and the drain portion by the forward / backward moving method of the movable inner die and the approaching / separating method of the movable out die. It can also be manufactured in the order of the tubular portion.

  The movable inner die and the movable out die can be moved manually or by means of various actuators.

  Note that the transition portion of the externally deformed drain tube is formed while the movable inner die and the movable out die are moving.

Below, the preferable method of this invention is demonstrated concretely.
3A is a front view (end view) showing a first arrangement state of the crosshead die, and FIG. 3B is a cross-sectional view showing a cross section taken along the line AA of FIG. 3A. . FIG. 3C is a front view (end view) showing a second arrangement state of the crosshead die, and FIG. 3D is a cross-sectional view showing a cross section taken along line BB in FIG. .

A preferable method of manufacturing an externally deformed drain tube of the present invention (referred to as a preferred first manufacturing method of the present invention) in which the externally deformed drain tube 21 is manufactured in the order of the tubular part 22, the transition part 23, and the drain part 24 is preferably A crosshead extruder 1 is used.
The crosshead type extruder 1 used is as described above.

  A preferred first manufacturing method of the present invention includes a step of forming the tubular portion 22 by moving the movable inner die 12 backward from the inside of the discharge hole 5 by bringing the divided bodies 16a of the movable out die 16 into close proximity and integrating them, and the movable out die 16. And the step of forming the drain portion 24 by moving the movable inner die 12 forward to the inside of the discharge hole 5 in this order.

Here, “consecutively” means that no other molding step is performed between the above-described molding steps, that is, the continuity of the molding step. It does not mean. Therefore, in the method of manufacturing an externally deformed drain tube of the present invention, the above-described forming step may be performed at intervals in time, that is, with a stop or a pause, within a range that does not affect the molding quality or the like. it can.
Preferably, it is performed without a time interval.

  In the preferred first manufacturing method of the present invention, first, the crosshead die 3 is arranged in the first arrangement state. That is, as shown in FIG. 3B, the movable inner die 12 is moved backward in the axial direction with respect to the fixed inner die 11 to be retracted from the discharge hole 5. Further, the two divided bodies 16a of the movable out die 16 are brought close to each other so as to be integrated. Then, the inner shape of the discharge hole 5 becomes the outer peripheral surface of the fixed inner die 11, and the outer shape becomes the inner surface of the movable out die 16. That is, as shown in FIG. 3A, the discharge hole 5 is annular. When the molding material is extruded in this arrangement state, the tubular portion 22 having an annular cross section is formed.

  In the preferred first manufacturing method of the present invention, the drain portion 24 is subsequently formed. In order to mold the drain part 24, the arrangement state of the crosshead die 3 is changed from the first arrangement state (see FIGS. 3A and 3B) to the second arrangement state (FIGS. 3C and 3). (See (d)). That is, the movable inner die 12 is advanced in the axial direction with respect to the fixed inner die 11 and is disposed flush with the discharge hole 5. Further, the two divided bodies 16a of the movable out die 16 are separated in the horizontal direction. Then, the inner shape of the discharge hole 5 becomes the outer peripheral surface of the movable inner die 12, and the outer shape becomes the inner surfaces of the out die body 15 and the movable out die 16. That is, as shown in FIG. 3C, the discharge hole 5 has an elliptical ring shape. When the molding material is extruded in this arrangement state, the drain part 24 having an elliptical cross section is formed.

  In the advancement process of the movable inner die 12 and the separation process of the divided body 16a, the shape of the discharge hole 5 changes from an annular shape to an elliptical shape, whereby the transition portion 23 is formed.

  In the preferred first production method of the present invention, the tubular portion 22, the transition portion 23, and the drain portion 24 can be extruded in this order to produce an externally deformed drain tube.

  The manufacturing method of the preferred outer shape deformed drain tube of the present invention (referred to as the preferred second manufacturing method of the present invention) in which the outer shape deformed drain tube 21 is manufactured in the order of the drain portion 24, the transition portion 23 and the tubular portion 22 is the molding order. Except for the difference, this is basically the same as the preferred first production method of the present invention.

  In the preferred second manufacturing method of the present invention, preferably, using the crosshead type extruder 1, the divided body 16 a of the movable out die 16 is separated, the movable inner die 12 is advanced into the discharge hole 5, and the drain portion 24. And the step of forming the tubular portion 22 by moving the movable inner die 12 backward from the inside of the discharge hole 5 and the step of forming the tubular portion 22 in this order. Do it.

  In the preferred second manufacturing method of the present invention, first, the crosshead die 3 is shifted to the second arrangement state. The specific transition method is the same as the method for shifting from the first arrangement state to the second arrangement state in the preferred first manufacturing method of the present invention. When the molding material is extruded in the second arrangement state shown in FIGS. 3C and 3D, the drain portion 24 having an elliptical cross section is formed.

  In the preferred second manufacturing method of the present invention, the tubular portion 22 is subsequently formed by shifting the arrangement state of the crosshead die 3 from the second arrangement state to the first arrangement state. The specific transition method is the same as the method of arranging in the first arrangement state in the preferred first manufacturing method of the present invention. When the molding material is extruded in this arrangement state, the tubular portion 22 having an annular cross section is formed.

  As described above, the transition portion 23 is formed in the process of moving the movable inner die 12 forward and the separation process 16a of the movable out die 16.

  In the preferred second manufacturing method of the present invention, the drain portion 24, the transition portion 23, and the tubular portion 22 can be extruded in this order to produce the externally deformed drain tube 21.

In the preferable first manufacturing method of the present invention and the preferable second manufacturing method of the present invention, the manufactured externally deformed drain tube is formed of a molding material, and changes in flexibility and mechanical strength are reduced in the axial direction. Further, a connecting member such as a tubular collar is not required.
Therefore, according to the preferred first manufacturing method of the present invention and the preferable second manufacturing method of the present invention, the change in flexibility and mechanical strength in the axial direction is small, and preferably an externally deformed drain tube configured with a small number of parts. 21 can be molded easily and continuously.

Although the molding material used for the manufacturing method of the external deformation | transformation drain tube of this invention is not specifically limited, From points, such as biocompatibility and mechanical characteristics, it is preferable that it is a silicone rubber composition.
In the present invention, thermosetting silicone rubber can be used for extrusion molding.

The thermosetting silicone rubber composition is not particularly limited as long as it is cured by heat, and a known one can be appropriately used.
For example, average composition formula: RnSiO _{(4-n) / 2} (R may be the same or different, substituted or unsubstituted monovalent hydrocarbon group, preferably 1 to 12 carbon atoms, more preferably carbon. It is a monovalent hydrocarbon group having 1 to 8 atoms, and n is a positive number of 1.95 to 2.05.) A thermosetting silicone rubber composition containing an organopolysiloxane represented by the formula:
Further, it contains an organopolysiloxane containing at least two alkenyl groups bonded to silicon atoms in one molecule, and an organohydrogenpolysiloxane containing at least two hydrogen atoms bonded to silicon atoms in one molecule. A thermosetting silicone rubber composition is also mentioned.

(Example 1)
Using the following thermosetting silicone rubber composition and the extruder 1 shown in FIG. 2, the externally deformed drain tube 21 shown in FIG. 1 was produced.
<Thermosetting silicone rubber composition>
100 parts by weight of silicone raw rubber (trade name “KE-78VBS”, manufactured by Shin-Etsu Chemical Co., Ltd.) and 43 parts by weight of hydrophobic fumed silica (trade name “Aerosil R974”, manufactured by Nippon Aerosil Co., Ltd.) Using a mixer, the mixture was uniformly mixed and heat treated at 150 ° C. for 2 hours to prepare a silicone rubber compound.
Next, 100 parts by mass of this silicone rubber compound, 2.0 parts by mass of organohydrogenpolysiloxane (trade name “C-25B”, manufactured by Shin-Etsu Chemical Co., Ltd.), platinum-based catalyst (trade name “C-25A”, Shin-Etsu) (Made by Chemical Industry Co., Ltd.) 0.5 parts by mass was blended and kneaded with a mixing roll to obtain an addition reaction type silicone rubber composition.

  The inner die 9 and the out die 8 were prepared as described above having a shape and dimensions that match the shape and dimensions of the outer shape deformed drain tube 21 to be manufactured. Therefore, the divided bodies 16a of the movable out die 16 are in pairs.

Specifically, the thermosetting silicone rubber composition was sequentially and continuously extruded so as to become the tubular portion 22, the transition portion 23, and the drain portion 24 by the preferred first manufacturing method of the present invention. That is, the two divided bodies 16a of the movable out die 16 are brought close to each other and integrated, the movable inner die 12 is retracted from the discharge hole 5, and the tubular portion 22 is formed, and the two divided bodies 16a of the movable out die 16 are formed. And the step of forming the drain part 24 by moving the movable inner die 12 forward into the discharge hole 5 in this order. The extruded molded body thus extruded was heated at 400 ° C. and vulcanized to produce an externally deformed drain tube 21.
In this externally deformed drain tube 21, the outer diameter of the drain part 24 was 10 mm and 3 mm, the wall thickness was 0.6 mm, and the outer diameter of the annular part 22 was Φ5 mm and the inner diameter Φ3 mm.

In this externally deformed drain tube 21, changes in flexibility and mechanical strength were confirmed as described above.
The bending radius of the tubular part 22 and the drain part 24 was 15 mm, the bending radius of the transition part 23 was 25 mm, and the rate of change in flexibility was 60%.
The tensile strength of the drain portion 24 was 110 N, the tensile strength of the drain portion 24 and the transition portion 23 was 120 N, the tensile strength of the tubular portion 22 was 100 N, and the tensile strength of the tubular portion 22 and the transition portion 23 was 95 N. Therefore, the rate of change in mechanical strength was 95% and 110%.
As described above, the externally deformed drain tube 21 of Example 1 was manufactured as a single member by extrusion molding, and was excellent in flexibility and mechanical strength in the axial direction.

(Comparative Example 1)
An externally deformed drain tube was manufactured by using the above thermosetting silicone rubber composition by the manufacturing method of the connector connection method described in Japanese Patent Publication No. 02-17185. Specifically, the drain part and the annular part were respectively extruded and connected, and the drain part and the annular part were connected by a connector and adhered.
Changes in flexibility and mechanical strength were confirmed in the obtained externally deformed drain tube.
The bending radius of the tubular portion 22 and the drain portion 24 was 15 mm, the bending radius of the transition portion 23 was 70 mm, and the rate of change in flexibility was 21%.
The tensile strength of the drain portion 24 was 110 N, the tensile strength of the drain portion 24 and the transition portion 23 was 70 N, the tensile strength of the tubular portion 22 was 100 N, and the tensile strength of the tubular portion 22 and the transition portion 23 was 50 N. Therefore, the rate of change in mechanical strength was 50% and 64%.
As described above, the externally deformed drain tube 21 of Comparative Example 1 includes three members, and the flexibility and mechanical strength in the axial direction are not sufficient.

1 Crosshead Extruder 2 Cylinder 3 Crosshead Die 4 Channel Cavity 5 Discharge Hole 7 Crosshead Die Body 8 Out Die (Outer Die)
9 Inner die (Indie)
DESCRIPTION OF SYMBOLS 11 Fixed inner die 12 Movable inner die 15 Out die main body 15a Through-hole 15b Discharge side surface 16 Movable out die 16a Divided body 21 External shape deformation drain tube 22 Tubular part (tubular discharge part)
22a, 24a Shaft hole 22b, 24b Tubular wall 23 Transition part 24 Drain part (tubular liquid collection part)

Claims (8)

A crosshead die of a crosshead type extruder for continuously extruding an externally deformed drain tube comprising a tubular portion having a shaft hole and a drain portion connected to the tubular portion and flatter than the tubular portion. Because
It has an out die having a discharge hole, and an inner die arranged in the discharge hole,
The out die has an out die body having a through hole, and a set of movable out dies disposed on the discharge side surface of the out die body so as to be close to and away from each other.
The inner die is a crosshead die having a fixed inner die whose tip is fixed in the discharge hole, and a movable inner die supported so as to be able to move forward and backward relative to the fixed inner die.   The crosshead die according to claim 1, wherein the movable inner die is supported so as to be able to move forward and backward on the outer circumferential side of the fixed inner die.   The crosshead die according to claim 1 or 2, wherein the movable out die is attached to the discharge side surface by screws.   The crosshead die according to any one of claims 1 to 3, wherein the movable out die is configured by a pair of divided bodies having an inner surface with an arc-shaped cross section.   A crosshead type extruder comprising the crosshead die according to any one of claims 1 to 4. An externally deformed drain tube comprising a tubular part having a shaft hole and a drain part connected to the tubular part and flatter than the tubular part, using the crosshead type extruder according to claim 5. A manufacturing method for manufacturing,
A manufacturing method of an externally deformed drain tube in which the movable inner die is moved forward and backward in accordance with the tubular portion and the drain portion, and the movable out die is moved close to or away from the drain portion. Forming the tubular part by bringing the movable out die close together and retreating the movable inner die from the discharge hole; and
The externally deformed drain according to claim 6, wherein the step of forming the drain portion is performed in this order or in the reverse order by separating the movable out die and advancing the movable inner die into the discharge hole. Tube manufacturing method.   The manufacturing method of the external deformation | transformation drain tube of Claim 6 or 7 which extrudes a thermosetting silicone rubber composition.

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