WO2021024794A1

WO2021024794A1 - Flexible tube production apparatus

Info

Publication number: WO2021024794A1
Application number: PCT/JP2020/028248
Authority: WO
Inventors: 良治菊澤
Original assignee: 株式会社プラ技研
Priority date: 2019-08-02
Filing date: 2020-07-21
Publication date: 2021-02-11
Also published as: JPWO2021024794A1; TWI760798B; JP6916564B2; TW202118526A

Abstract

Provided is a flexible tube production apparatus capable of precisely changing the mixing ratio of two types of resin with a good response. The flexible tube production apparatus according to one embodiment of the present invention is provided with: a molding device which extrudes and molds supplied resins on the surface of a braid wire and has a first extruder for extruding a first resin, a second extruder for extruding a second resin softer than the first resin, a first resin supply path to which the first resin is supplied from the first extruder, and a second resin supply path to which the second resin is supplied from the second extruder; a first gear pump provided in the middle of the first resin supply path; and a second gear pump provided in the middle of the second resin supply path. The first gear pump and the second gear pump are integrally formed with the molding device.

Description

Flexible tube manufacturing equipment

The present invention relates to a flexible tube manufacturing apparatus for extrusion-molding a flexible tube formed by coating the outer surface of a blade wire with a resin.

In medical institutions, tube-shaped medical devices called catheters are used to inject drug solutions, contrast media, etc. into a predetermined part of the patient's body, and to take out body fluids, etc. in the body. Since this catheter is inserted into the living body through a bent blood vessel or the like, flexibility is required in the distal end side portion so as not to damage the blood vessel or the like and to easily bend along the bent portion such as the blood vessel or the like. Be done. On the other hand, the portion of the catheter that is not inserted into the living body is required to have appropriate rigidity so that the catheter can be easily operated. Therefore, various catheter manufacturing devices have been proposed in which the hardness is gradually changed along the length direction so that the tip side is soft and the hand side is hard. For example, Patent Document 1 describes a catheter tube having a tilting property in which the flexural modulus continuously increases from the distal end side to the proximal end side.

Japanese Unexamined Patent Publication No. 8-57035

In Patent Document 1, as one of the methods for melt-extruding by changing the mixing ratio of two or more kinds of synthetic resins, at least one supply rate of the melt-synthesized resin supplied from two or more extruders is changed over time. A method of continuously changing, mixing and extruding is described. However, when the resin supply speed from the extruder, that is, the extrusion speed of the extruder is changed, the flow rate of the resin does not change immediately because the pressure of the resin existing in the flow path remains. As a result, there is a problem that the mixing ratio of two or more kinds of resins does not change continuously.

As a method of precisely controlling the flow rate of the resin, a method of providing a gear pump between the extruder and the molding device and controlling the discharge amount of the gear pump instead of the extrusion speed of the extruder can be considered. However, in this case, by connecting the extruder, the gear pump, and the molding device in series, the resin supply path becomes long, and the resin flow rate is changed by the gear pump, and then the mixing ratio of the resin actually extruded from the die is changed. There is a problem that the response until the change is deteriorated.

Therefore, an object of the present invention is to provide a flexible tube manufacturing apparatus capable of changing the mixing ratio of two kinds of resins precisely and with good response.

The flexible tube manufacturing apparatus according to one embodiment of the present invention includes a first extruder that extrudes a first resin, a second extruder that extrudes a second resin that is more flexible than the first resin, and a first extruder. It has a first resin supply path to which the first resin is supplied from the extruder and a second resin supply path to which the second resin is supplied from the second extruder, and the supplied resin is bladed. A molding device for extrusion molding on the surface of the wire, a first gear pump provided in the middle of the first resin supply path, and a second gear pump provided in the middle of the second resin supply path are provided. The first gear pump and the second gear pump are provided integrally with the molding apparatus.

Further, the flexible tube manufacturing apparatus according to another embodiment of the present invention includes a first extruder that extrudes a first resin, a second extruder that extrudes a second resin that is more flexible than the first resin, and a second extruder. A third extruder that extrudes a third resin that is more flexible than the second resin, a first resin supply path in which the first resin is supplied from the first extruder, and a second from the second extruder. Has a second resin supply path to which the resin of the above is supplied and a third resin supply path to which the third resin is supplied from the third extruder, and the supplied resin is extruded onto the surface of the blade wire. A molding device for molding, a first gear pump provided in the middle of the first resin supply path, a second gear pump provided in the middle of the second resin supply path, and a middle of the third resin supply path. A third gear pump is provided in the above, and a first gear pump, a second gear pump, and a third gear pump are integrally provided with the molding apparatus.

According to the present invention, it is possible to provide a flexible tube manufacturing apparatus capable of changing the mixing ratio of two types of resins precisely and with good response.

FIG. 1 is a front view showing a schematic configuration of a flexible tube manufacturing apparatus according to an embodiment. FIG. 2 is a right side view of the flexible tube manufacturing apparatus shown in FIG. FIG. 3 is a top view of the flexible tube manufacturing apparatus shown in FIG. FIG. 4 is a cross-sectional view taken along the IV-IV line shown in FIG. FIG. 5 is a cross-sectional view taken along the VV line shown in FIG. FIG. 6 is a cross-sectional view taken along the VI-VI line shown in FIG. FIG. 7 is a cross-sectional view taken along the VII-VII line shown in FIG. FIG. 8A is a schematic view showing an example of a flexible tube that can be manufactured by the flexible tube manufacturing apparatus according to the embodiment. FIG. 8B is a schematic view showing another example of the flexible tube that can be manufactured by the flexible tube manufacturing apparatus according to the embodiment.

Hereinafter, embodiments of the present invention will be described. In the following description, an example in which the present invention is applied to a flexible tube manufacturing apparatus in which a blade (net tube) is provided on the outer surface of an inner layer tube which is a resin layer and the blade is covered with an outer layer tube which is a resin layer will be described. To do. An example of such a flexible tube is a catheter shaft. However, the catheter shaft is only an example of a flexible tube, and the present invention is also applicable to a flexible tube manufacturing apparatus for other purposes such as a flexible tube used for an endoscope.

1, FIG. 2 and FIG. 3 are a front view, a right side view, and a top view showing a schematic configuration of a flexible tube manufacturing apparatus according to an embodiment, respectively.

The flexible tube manufacturing apparatus 100 is an apparatus for extruding a flexible tube 7 using a resin, and includes a first extruder 1a, a second extruder 1b, a third extruder 1c, and a molding apparatus. 2, a first gear pump 3a, a second gear pump 3b, a third gear pump 3c, and a control device 4 for controlling the molding device 2. A drive mechanism 5a, a drive mechanism 5b, and a drive mechanism 5c for driving each of the first gear pump 3a, the second gear pump 3b, and the third gear pump 3c are attached. The drive mechanisms 5a to 5c include, for example, a motor and a speed reducer. Each device constituting the flexible tube manufacturing device 100 is attached to the housing 8 and fixed on a predetermined stand or the like. Further, although not shown, on the upstream side and the downstream side of the molding device 2, a supply device for supplying the blade wire 6, a cooling device for cooling the extruded flexible tube, and extrusion molding were performed. A pick-up device or the like for picking up the flexible tube 7 is appropriately provided. The blade wire 6 is conveyed from the right direction to the left direction in FIGS. 1 and 3. The blade wire 6 is, for example, in a state where a blade (net tube) is provided on an inner layer tube and a core wire (guide wire) is inserted through a hollow portion in the middle of the inner layer. The flexible tube 7 is provided with an outer layer tube on the surface of the blade wire 6, and a catheter shaft can be obtained by extracting the core wire of the blade wire 6 after molding the outer layer tube.

The first extruder 1a, the second extruder 1b, and the third extruder 1c are, for example, screw extruders, which melt resin pellets and extrude them from a discharge port at the tip. The first extruder 2a, the second extruder 2b, and the third extruder 2c include a first resin, a second resin, and a second resin having different characteristics such as hardness, color, elastic modulus, strength, and chemical resistance. A third resin is supplied, respectively. In the present embodiment, the first resin is the resin having the highest hardness, the second resin is a resin that is more flexible than the first resin, and the third resin is a resin that is more flexible than the second resin. .. The molten resin extruded from the first extruder 1a and the second extruder 1b is kneaded at a predetermined mixing ratio by the kneading mechanism 16 described later. On the other hand, the molten resin extruded from the third extruder 1c is supplied to the third valve 18, which will be described later.

The molding device 2 is a device that extrudes the resin supplied from the first extruder 1a, the second extruder 1b, and the third extruder 1c onto the surface of the blade wire 6. Hereinafter, the detailed configuration of the molding apparatus 2 will be described later with reference to FIGS. 1 to 7.

In the present embodiment, the molding apparatus 2 is composed of the

divided bodies

26 and 27. The split body 26 is a unit that selects, switches, and mixes the resin to be used, and extrudes the resin onto the surface of the blade wire 6. On the other hand, the split body 27 is provided on the upstream side in the resin flow direction with respect to the split body 26, and includes the split body 26, the first extruder 1a, the second extruder 1b, and the third extruder 1c. It is a unit for connecting.

First, the split body 27 will be described.

FIG. 4 is a cross-sectional view taken along the IV-IV line shown in FIG. 1, FIG. 5 is a cross-sectional view taken along the VV line shown in FIG. 1, and FIG. 6 is a cross-sectional view taken along the VI line shown in FIG. -It is a cross-sectional view along the VI line.

In the present embodiment, as an example, the divided body 27 is divided into three metal blocks 25a to 25c stacked vertically. The metal blocks 25a to 25c are fixed and integrated by a fixture such as a bolt (not shown). Note that FIG. 4 corresponds to a top view of the metal block 25a (divided body 27), and FIG. 5 corresponds to a top view of the metal block 25b. As shown in FIGS. 5 and 6, the split body 27 has a first resin supply path 19a to which the first resin is supplied from the first extruder 1a and a second resin supply passage 19a from the second extruder 1b to the second. A second resin supply path 19b to which the resin is supplied and a third resin supply path 19c to which the third resin is supplied from the third extruder 1c are provided. The first resin supply path 19a, the second resin supply path 19b, and the third resin supply path 19c all pass from the side surface of the metal block 25b through the inside of the metal blocks 25b and 25a to the upper surface of the metal block 25a. It is a flow path leading to. On the side surface of the metal block 25b, openings 28a, openings 28b and openings 28c corresponding to the first resin supply 19a, the second resin supply path 19b and the third resin supply path 19c are provided. A first extruder 1a, a second extruder 1b, and a third extruder 1c are connected to the opening 28a, the opening 28b, and the opening 28c, respectively. On the upper surface of the metal block 25a, openings 29a, openings 29b, and openings 29c corresponding to the first resin supply path 19a, the second resin supply path 19b, and the third resin supply path 19c are provided. .. The openings 29a to 29c on the upper surface of the metal block 25a are openings for supplying resin to the divided body 26, and are provided in the flow path provided in the divided body 26 in a state where the divided

bodies

26 and 27 are integrated. Be connected.

As an example, FIG. 6 shows a cross section of the third resin supply path 19c. The first resin supply path 19a and the second resin supply path 19b are configured in substantially the same manner as the third resin supply path 19 shown in FIG. 6, except that the flow path lengths are different.

A first gear pump 3a, a second gear pump 3b, and a third gear pump 3c are provided in the middle of each of the first resin supply path 19a, the second resin supply path 19b, and the third resin supply path 19c. ing. As shown in FIGS. 5 and 6, the first gear pump 3a, the second gear pump 3b, and the third gear pump 3c have two gears 31 that mesh with each other in the gear accommodating portion 30 provided in the metal block 25b. It is rotatably housed and is configured by sealing the upper and lower surfaces of the metal block 25b with the

metal blocks

25a and 25c, respectively. The gear 31 constituting the first gear pump 3a is connected to the drive mechanism 5a shown in FIG. 1, the gear 31 constituting the second gear pump 3b is connected to the drive mechanism 5b shown in FIG. 1, and the third gear pump The gear 31 constituting the 3c is connected to the drive mechanism 5c shown in FIG.

Next, the split body 26 will be described.

FIG. 7 is a cross-sectional view taken along the VII-VII line shown in FIG.

As shown in FIG. 7, the split body 26 includes a die 10, a kneading mechanism 16, a first valve 17a, a second valve 17b, and a third valve 18. In the present embodiment, as an example, the divided body 26 is divided into three metal blocks 24a to 24c, the metal block 24a is provided with a die 10 and a third valve 18, and the metal block 24b is provided with a first valve. The valve 17a and the second valve 17b are provided, and the kneading mechanism 16 is provided on the metal blocks 24b and 24c.

The die 10 is a mold for extruding resin onto the outer surface of the blade wire 6, and includes an inner mold 11 and an outer mold 12. The inner mold 11 is provided with a through hole 13 through which the blade wire 6 is inserted in the central shaft portion. The outer mold 12 is formed of a part of the metal block 24a and has a hollow portion for accommodating the inner mold 11. A resin flow path 15 formed of a predetermined gap is formed between the outer peripheral surface of the inner mold 11 and the inner peripheral surface of the hollow portion of the outer mold 12. The outer mold 12 has an extrusion port 14 coaxial with the central axis of the inner mold 11. The extrusion port 14 constitutes the front end portion of the flow path 15. The flow path 15 is connected to a flow path connected to a third valve 18, which will be described later. The resin supplied from the third valve 18 to the flow path 15 flows to the extrusion port 14 side and is extruded to the surface of the blade wire 6 which passes through the through hole 13 of the inner die 11 and the extrusion port 14 and is fed forward. Is done. The inner mold 11 is fixed to the outer mold 12.

The kneading mechanism 16 includes a screw 21 and a motor 22. The screw 21 is housed in a hollow portion provided in the metal blocks 24b and 24c. A flow path 23 formed of a predetermined gap is formed between the outer peripheral surface of the screw 21 and the inner peripheral surface of the hollow portion of the metal blocks 24b and 24c. One or both of the first resin and the second resin are supplied to the flow path 23 of the kneading mechanism 16. A plurality of protrusions or pins are provided on the outer peripheral surface of the screw 21, and the kneading mechanism 16 is one type or two existing in the flow path 23 by rotating around the central axis by the rotational force of the motor 22. Various types of resins can be kneaded and discharged. In the present embodiment, an example in which the kneading mechanism 16 is configured by using the screw 21 has been described, but the present invention is not particularly limited as long as the resin in the flow path can be kneaded, and a kneader may be used instead of the screw 21. good. The rotation of the motor 22 is controlled by the control device 4.

The first valve 17a is provided between the kneading mechanism 16 and the first gear pump 3a, and controls the supply of the first resin to the kneading mechanism 16. The first valve 17a has a columnar valve body having a flow path (not shown) for flowing the resin inside. The valve body of the first valve 17a is connected to a drive mechanism 20a such as a motor and is rotatable around its central axis. The first valve 17a has a state in which the first gear pump 3a and the kneading mechanism 16 communicate with each other and a state in which the first gear pump 3a and the kneading mechanism 16 are cut off according to the rotational position of the valve body. Can be switched. In a state where the first gear pump 3a and the kneading mechanism 16 communicate with each other, the first resin supply path 19a and the flow path 23 of the kneading mechanism 16 are connected by a flow path (not shown) provided in the valve body.

The second valve 17b is provided between the kneading mechanism 16 and the second gear pump 3b, and controls the supply of the second resin to the kneading mechanism 16. The second valve 17b has the same configuration as the first valve 17. That is, the second valve 17b has a columnar valve body having a flow path (not shown) for flowing the resin inside, and the valve body of the second valve 17b is attached to a drive mechanism 20b such as a motor. It is connected and is rotatable around its central axis. The second valve 17b has a state in which the second gear pump 3b and the kneading mechanism 16 communicate with each other and a state in which the second gear pump 3b and the kneading mechanism 16 are cut off according to the rotational position of the valve body. Can be switched. In a state where the second gear pump 3b and the kneading mechanism 16 communicate with each other, the second resin supply path 19a and the flow path 23 of the kneading mechanism 16 are connected by a flow path (not shown) provided in the valve body.

The third valve 18 selectively dies one of the resin extruded from the kneading mechanism 16 and the third resin supplied from the third extruder 1c via the third resin supply path 19c. It can be supplied to 10. The third valve 18 has a columnar valve body having a flow path (not shown) for flowing resin inside, and the valve body of the third valve 18 is connected to a drive mechanism 20c such as a motor. , Is rotatable around its central axis. The third valve 18 has a state in which the flow path 23 of the kneading mechanism 16 and the flow path 15 of the die 10 communicate with each other according to the rotation position of the valve body, and the third gear pump 3c and the flow path 15 of the die 10. It is possible to switch between the communication state and the communication state. In a state where the flow path 23 of the kneading mechanism 16 and the flow path 15 of the die 10 communicate with each other, the flow path 23 and the flow path 15 are connected by a flow path (not shown) provided inside the valve body, and a third gear pump is used. The communication between 3c and the flow path 15 of the die 10 is cut off. In a state where the third gear pump 3c and the flow path 15 of the die 10 communicate with each other, the third resin supply path 19c and the flow path 15 connected to the third gear pump 3c are connected by a flow path (not shown) provided in the valve body. Then, the flow path 23 of the kneading mechanism 16 and the flow path 15 of the die 10 are blocked from each other.

The control device 4 includes a computer, and by controlling the driving amounts of the driving devices 5a to 5c, the discharge amounts of the first gear pump 3a, the second gear pump 3b, and the third gear pump 3c (per unit time). The flow rate of the resin) can be adjusted. Further, the control device 5 can switch the states of the first valve 17a, the second valve 17b, and the third valve 18 by controlling the driving amounts of the driving mechanisms 20a to 20c. Further, the control device 4 rotates the motor 22 constituting the kneading mechanism 16 during the execution of extrusion molding, and controls the rotation speed to a predetermined value.

Hereinafter, a method of manufacturing a flexible tube using the flexible tube manufacturing apparatus 100 according to the present embodiment will be described.

8A and 8B are schematic views showing an example of a flexible tube that can be manufactured by the flexible tube manufacturing apparatus according to the embodiment.

The flexible tube 70 shown in FIG. 8A is formed by coating a blade wire 6 having a blade (net tube) on the outer surface of the inner layer tube with an outer layer tube made of a resin layer, and the hardness of the resin of the outer layer tube gradually becomes flexible. It includes a hardness transition portion 71 and a soft chip 72 made of a resin that is connected to the tip portion of the hardness transition portion 71 and is more flexible than the resin that covers the tip of the hardness transition portion 71. The soft tip 72 is provided at the tip (insertion side) of the catheter, which can suppress damage to blood vessels and further improve safety. The length of the soft chip 72 is, for example, several mm to several cm, and the hardness of the resin layer (outer layer tube) constituting the soft chip 72 is constant. Conventionally, the flexible tube shown in FIG. 8A is manufactured by separately molding a hardness transition portion 71 and a flexible tube to be a soft tip 72, and joining the soft tip 72 to the tip of the hardness transition portion 71 by heat welding. Was common. On the other hand, in the flexible tube manufacturing apparatus 100 according to the present embodiment, the hardness transition portion 71 and the soft tip 72 can be continuously extruded, and the hardness transition portion 71 and the soft tip 72 are smoothed. The length of the soft chip 72 can be freely changed as well as being completely connected.

When the flexible tube 70 is manufactured by using the flexible tube manufacturing apparatus 100 according to the present embodiment, first, a first resin and a second resin that is more flexible than the first resin are used, and the kneading mechanism 16 is relative. The hardness transition portion 71 is extruded by extruding the resin onto the blade wire 6 while reducing the proportion of the first hard resin. More specifically, the control device 4 determines the state (rotational position) of the first valve 17a and the second valve 17b so that both the first gear pump 3a and the second gear pump 3b communicate with the kneading mechanism 16. The state (rotational position) of the third valve 18 is controlled so that the kneading mechanism 16 communicates with the die 10. In this state, the control device 4 controls the

drive devices

5a and 5b to continuously reduce the discharge amount of the first resin by the first gear pump 3a at a predetermined rate of change, and the second gear pump 3b. The discharge amount of the second resin is continuously increased at the same rate of change as the change rate of the discharge amount of the first resin. In the process of changing the mixing ratio of the first resin and the second resin, the pressure fluctuation of the resin in the flow path from the kneading mechanism 16 to the die 10 is suppressed, and the dimensional stability of the molded flexible tube is maintained. Therefore, the total amount of the first resin and the second resin supplied to the kneading mechanism 16 is kept constant. Therefore, the control unit 4 matches the rate of change in the discharge amount of the first gear pump 3a with the rate of change in the discharge amount of the second gear pump 3b.

When an outer layer tube made of only the first resin is extruded at the end portion (hand side portion at the time of use) of the hardness transition portion 71, the control device 4 uses the first gear pump 3a and the second gear pump. Before communicating both of 3b with the kneading mechanism 16, the first gear pump 3a and the kneading mechanism 16 communicate with each other, and the first gear pump 3b and the kneading mechanism 16 are cut off from each other. Assuming that the state (rotational position) of the valve 17a and the second valve 17b is controlled, the discharge amount of the first gear pump 3a is controlled to a predetermined discharge amount. Further, when an outer layer tube made of only the second resin is extruded at the tip portion (insertion side portion at the time of use) of the hardness transition portion 71, the control device 4 uses the first gear pump 3a and the second gear pump. The state in which both 3b are communicated with the kneading mechanism 16 is changed to a state in which the second gear pump 3b and the kneading mechanism 16 are communicated with each other and the first gear pump 3a and the kneading mechanism 16 are cut off. As described above, the discharge amount of the second gear pump 3b is controlled to a predetermined discharge amount, assuming that the state (rotation position) of the first valve 17a and the second valve 17b is controlled.

Next, the soft tip 72 is molded. The control device 4 controls the discharge amounts of the first gear pump 3a and the second gear pump 3b, and after the ratio of the first resin reaches a predetermined target value, the third gear pump 3c is at a predetermined timing. Controls the state (rotational position) of the third valve so that the third valve communicates with the die 10, and controls the discharge amount of the third gear pump 3c to a predetermined discharge amount.

The control device 4 determines the discharge amounts of the first gear pump 3a, the second gear pump 3b, and the third gear pump 3c, and the rotational positions of the first valve 17a, the second valve 17b, and the third valve 18. By controlling as shown in FIG. 8A, the flexible tube 70 shown in FIG. 8A can be manufactured.

Further, the flexible tube manufacturing apparatus 100 according to the present embodiment can also manufacture a flexible tube 73 having a hardness transition portion 74 without a soft chip as shown in FIG. 8B. Specifically, in the control by the control device 4 described above, the flexible tube shown in FIG. 8B is formed by not switching the rotation position of the third valve 18 (that is, not communicating the third valve 18 and the die 10). 73 can be obtained.

The initial value and the target value (minimum value) of the ratio of the first resin when molding the hardness transition portion 71 are arbitrary.

As described above, the flexible tube manufacturing apparatus 100 according to the present embodiment has the middle of the first resin supply passage 19a in the molding apparatus 2, the middle of the second resin supply passage 19b, and the third resin supply. A first gear pump 3a, a second gear pump 3b, and a third gear pump 3c are provided in the middle of the road 19c, respectively. When the first gear pump 3a, the second gear pump 3b, and the third gear pump 3c are built in the molding apparatus 2 as in the present embodiment, the gear pump to the die 10 are compared with the case where the gear pump is provided outside the molding apparatus. The flow path length to the extrusion port 14 can be shortened. Therefore, in the flexible tube manufacturing apparatus 100 according to the present embodiment, it is possible to improve the response from adjusting the discharge amount of the gear pump until the mixing ratio of the resin actually extruded from the die changes. The split body 27 constituting the molding apparatus 2 according to the present embodiment is a connection unit for connecting the first extruder 1a, the second extruder 1b, and the third extruder 1c, but is a flexible tube manufacturing. This is a part necessary for avoiding interference between a plurality of devices constituting the device 100 and arranging each device at a position excellent in maintainability. Flexible tube manufacturing equipment that can change the mixing ratio of two or more types of resin is equipped with many equipment such as valves, kneading mechanisms, and drive mechanisms for these, so the same number of extruders as the types of resin are arranged without interference. However, in order to connect to the molding apparatus, the split body 27 is required. In the flexible tube manufacturing apparatus 100 according to the present embodiment, since the gear pump is built in the split body 27 required for arranging the extruder and connecting the extruder and the molding apparatus, from the gear pump to the die as compared with the same type of apparatus. The flow path of the above can be shortened, and the above-mentioned response can be improved. Further, since the gear pump is a device capable of precisely controlling the discharge amount, the resin supply amount to the kneading mechanism 16 and the die 10 can be precisely controlled by incorporating the gear pump in the molding device 2. it can. Therefore, in the flexible tube manufacturing apparatus 100 according to the present embodiment, the mixing ratio of the first resin and the second resin constituting the hardness transition portion 71 can be continuously changed, and the dimensional stability of the flexible tube 7 can be changed. Also excellent.

Further, in the flexible tube manufacturing apparatus 100 according to the present embodiment, the first valve 17a, the second valve 17b, and the third valve 18 are used to connect the flow path 23 of the kneading mechanism 16 and the first gear pump 3a. Between the flow path 23 of the kneading mechanism 16 and the second gear pump 3b, between the kneading mechanism 16 and the flow path 15 of the die 10, and between the third gear pump 3c and the flow path 15 of the die 10. Can be cut off as appropriate. Therefore, it is possible to prevent the resin from flowing back from the kneading mechanism 16 or the die 10 toward the upstream side while the resin is not supplied to the kneading mechanism 16 or the die 10.

Further, by controlling the discharge amounts of the first gear pump 3a and the second gear pump 3b in a state where both the first gear pump 3a and the second gear pump 3b and the kneading mechanism 16 are in communication with each other, two kinds of resins are used. The mixing ratio of can be changed continuously and precisely.

(Modification example)
In the above embodiment, an apparatus capable of manufacturing a flexible tube having the soft chip shown in FIG. 8A has been described. However, when configuring an apparatus for manufacturing a flexible tube without a soft tip shown in FIG. 8B, the third extruder 1c, the third resin supply path 19c, and the third gear pump are used from the above-mentioned flexible tube manufacturing apparatus 100. The 3c, the drive mechanism 5c, the third valve 18, and the drive mechanism 20c may be omitted, and the flow path 23 of the kneading mechanism 16 may be connected to the flow path 15 of the die 10. Also in this configuration, the first gear pump 3a and the second gear pump 3b are provided in the middle of the first resin supply path 19a and the middle of the second resin supply path 19b in the molding apparatus 2, respectively. The flow path from the gear pump to the extrusion port 14 of the die 10 can be shortened to improve the response of the above-mentioned mixing ratio change.

Further, in the above embodiment, the structures of the first valve 17a, the second valve 17b, and the third valve 18 are not particularly limited, and may have a structure capable of realizing the functions of the above-mentioned valves. ..

The present invention can be used as a flexible tube manufacturing apparatus such as a catheter shaft used for manufacturing a medical catheter and a tube used for an endoscope.

1a 1st extruder 1b 2nd extruder 1c 3rd extruder 2 Molding device 3a 1st gear pump 3b 2nd gear pump 3c 3rd gear pump 4 Control device 6 Blade wire 7 Flexible tube 10 Die 13 Through hole 14 Extrusion port 16 Kneading mechanism 17a 1st valve 17b 2nd valve 18 3rd valve 19a 1st resin supply path 19b 2nd resin supply path 19c 3rd resin supply path 100 Flexible tube manufacturing apparatus

Claims

Flexible tube manufacturing equipment
A first extruder that extrudes the first resin,
A second extruder that extrudes a second resin that is more flexible than the first resin, and
It has a first resin supply path to which the first resin is supplied from the first extruder, and a second resin supply path to which the second resin is supplied from the second extruder. , A molding device that extrudes the supplied resin onto the surface of the blade wire,
A first gear pump provided in the middle of the first resin supply path and
A second gear pump provided in the middle of the second resin supply path is provided.
A flexible tube manufacturing apparatus in which the first gear pump and the second gear pump are integrally provided with the molding apparatus.
The molding device is
A die having a through hole through which the blade wire is inserted and an extrusion port for extruding resin onto the surface of the blade wire passing through the through hole.
A kneading mechanism capable of kneading the first resin and the second resin and extruding them into the die.
A state in which the kneading mechanism and the first gear pump are provided so that the first gear pump and the kneading mechanism communicate with each other and a state in which the first gear pump and the kneading mechanism are cut off from each other. The first switchable valve and
A state in which the kneading mechanism and the second gear pump are provided so that the second gear pump and the kneading mechanism communicate with each other and a state in which the second gear pump and the kneading mechanism are cut off from each other. With a switchable second valve,
Equipped with a control device
The control device has a first state in which the first gear pump and the kneading mechanism communicate with each other and the second gear pump and the kneading mechanism are cut off at the time of extrusion molding of the flexible tube. , The second state in which both the first gear pump and the second gear pump communicate with the kneading mechanism, the second gear pump and the kneading mechanism communicate with each other, and the first gear pump and the kneading mechanism are communicated with each other. The flexible tube manufacturing apparatus according to claim 1, wherein the states of the first valve and the second valve can be switched between the state of the first valve and the state of the second valve, which is cut off from the kneading mechanism.
In the control device, when the first valve and the second valve are in the second state, the discharge amount of the first resin by the first gear pump and the second by the second gear pump. The flexible tube manufacturing apparatus according to claim 2, wherein the ratio of the first resin supplied to the kneading mechanism is continuously increased or decreased by continuously changing the discharge amount of the resin of 2.
Flexible tube manufacturing equipment
A first extruder that extrudes the first resin,
A second extruder that extrudes a second resin that is more flexible than the first resin, and
A third extruder that extrudes a third resin that is more flexible than the second resin,
A first resin supply path to which the first resin is supplied from the first extruder, a second resin supply path to which the second resin is supplied from the second extruder, and the first. A molding apparatus having a third resin supply path to which the third resin is supplied from the extruder of No. 3 and extruding the supplied resin onto the surface of the blade wire.
A first gear pump provided in the middle of the first resin supply path and
A second gear pump provided in the middle of the second resin supply path and
A third gear pump provided in the middle of the third resin supply path is provided.
A flexible tube manufacturing apparatus in which the first gear pump, the second gear pump, and the third gear pump are integrally provided with the molding apparatus.
The molding device is
A die having a through hole through which the blade wire is inserted and an extrusion port for extruding resin onto the surface of the blade wire passing through the through hole.
A kneading mechanism capable of kneading and extruding the first resin and the second resin,
A state in which the kneading mechanism and the first gear pump are provided so that the first gear pump and the kneading mechanism communicate with each other and a state in which the first gear pump and the kneading mechanism are cut off from each other. The first switchable valve and
A state in which the kneading mechanism and the second gear pump are provided so that the second gear pump and the kneading mechanism communicate with each other and a state in which the second gear pump and the kneading mechanism are cut off from each other. With a switchable second valve,
A third valve capable of selectively supplying any of the resin discharged from the kneading mechanism and the third resin extruded from the third extruder to the die.
Equipped with a control device
The control device has a first state in which the first gear pump and the kneading mechanism communicate with each other and the second gear pump and the kneading mechanism are cut off at the time of extrusion molding of the flexible tube. , The second state in which both the first gear pump and the second gear pump communicate with the kneading mechanism, the second gear pump and the kneading mechanism communicate with each other, and the first gear pump and the kneading mechanism are communicated with each other. The states of the first valve and the second valve can be switched between the third state in which the kneading mechanism and the kneading mechanism are cut off, and further, the kneading mechanism and the die communicate with each other. The flexible tube manufacturing apparatus according to claim 4, wherein the state of the third valve can be switched between the state of 4 and the fifth state in which the die of the third gear pump communicates with the die.
In the control device, when the first valve and the second valve are in the second state, the discharge amount of the first resin by the first gear pump and the second by the second gear pump. The flexible tube manufacturing apparatus according to claim 5, wherein the ratio of the first resin supplied to the kneading mechanism is continuously increased or decreased by continuously changing the discharge amount of the resin of 2.
The control device claims that the state of the third valve is switched from the fourth state to the fifth state after the ratio of the first resin supplied to the kneading mechanism reaches a predetermined value. Item 6. The flexible tube manufacturing apparatus according to Item 6.