WO2018181323A1 - Parison production method and parison production apparatus - Google Patents

Abstract

Provided is a method for producing a parison that has a symmetrical shape between one end side thereof and the other end side thereof, that is used to produce a balloon used for a balloon catheter, and that has an extension part at both ends of a straight barrel part thereof, the method comprising: a heating step (A) for simultaneously heating a part on one end side of a straight-pipe parison tube 1 and a part on the other end side thereof; and a stretching step (B) for simultaneously stretching the parts heated in the heating step by applying a tensional force (arrows a2, a3) to both ends of the parison tube 1.

Description

PARISON MANUFACTURING METHOD AND PARISON MANUFACTURING DEVICE

The present invention relates to a parison manufacturing method for manufacturing a balloon included in a balloon catheter used for IABP (intra-aortic balloon pumping) and the like, and a parison manufacturing apparatus suitable for carrying out the manufacturing method.

IABP (intra-aortic balloon pumping) is performed as a treatment for lowering cardiac function, in which a balloon catheter is inserted into the aorta and the balloon is expanded and contracted in accordance with the pulsation of the heart to assist the cardiac function. An IABP balloon catheter used for IABP is inserted from the femoral artery or the like, and is used in a state where the balloon is placed in the descending aorta of the chest.

The balloon used for such an IABP balloon catheter has a cone portion (shoulder portion) formed in a tapered shape at both ends of the straight barrel portion, and a straight barrel neck portion at the tip of each cone portion. Each has an arranged shape. The balloon is mounted by attaching the neck portion to the outer surface of the catheter sheath.

Such a balloon is manufactured by biaxial stretch blow molding of a parison (tube) formed into a tubular shape by extrusion molding. As a manufacturing technique of the parison for that purpose, although it relates to a balloon catheter for PTCA (angioplasty), not a balloon catheter for IABP, the one described in Patent Document 1 is known.

In this technique, in order to improve the uniformity of the film thickness of the balloon, as a parison used for blow molding, a both-ends different diameter (thin diameter) tube whose both end parts are made thinner than the straight body part is used. . According to Patent Document 1, in the case of extrusion molding, both ends have different diameters by appropriately changing and controlling the extrusion conditions by the extruder, the take-up conditions by the take-up machine, and the like by alternately forming thin portions and thick portions. Manufactured.

As another method for producing such a tube with different diameters at both ends, a method in which the portions near the both ends of the tube formed into a straight tube by extrusion molding are heated and stretched, respectively, has been put into practical use. In this method, a part of one end side of a tube formed in a straight tube shape is heated with a heating mold, tension is applied to both ends of the tube, the heated part on one end side is stretched, and then cooled. Subsequently, a part on the other end side of the tube is similarly heated with a heating mold, and tension is applied to both ends of the tube to extend the heated part on the other end side, and then the tube is cooled.

Thus, conventionally, after performing the first stretching for heating, stretching and cooling a part of one end side of the tube, the second stretching for heating, stretching and cooling a part of the other end side is performed by the first stretching. The stretching is performed under substantially the same conditions as the setting conditions (heating temperature, heating time, stretching speed, stretching length, cooling time, etc.) during stretching. Here, it is preferable that one end side and the other end side in the longitudinal direction of the balloon are symmetrical to each other, and therefore, the parison is also preferably symmetrical.

However, when the one end side and the other end side are sequentially stretched as in the prior art, at the time of the second stretching, there is an influence of the portion stretched by the first stretching, and the environmental conditions (atmosphere over time) It is difficult to make the actual stretching conditions the same in the first stretching and the second stretching, and therefore the stretched portions (stretched portions) do not have a symmetrical shape with each other. There was a case. Although it is theoretically possible to make the setting conditions for the second stretching different from the setting conditions for the first stretching (adjusted appropriately) so that they are symmetrical with each other, In order to influence each other, in practice, obtaining the optimum conditions requires a very complicated operation and is not practical.

JP 2001-321444 A

The present invention has been made in view of such a situation, and the object thereof is suitable for carrying out a method for manufacturing a parison capable of manufacturing a balloon having a symmetrical shape on one end side and the other end side thereof and the method. Is to provide a simple parison manufacturing apparatus.

The parison manufacturing method according to the first aspect of the present invention includes:
A method for producing a parison having stretched portions at both ends of a straight body portion for producing a balloon used for a balloon catheter,
A heating step of simultaneously heating a part of one end side and a part of the other end side of the straight tubular parison tube;
A stretching process in which tension is applied to both ends of the parison tube and the portions heated in the heating process are stretched simultaneously.

In the parison manufacturing method according to the first aspect of the present invention, a part of one end side and a part of the other end side of the tube for parison are heated at the same time, tension is applied to both ends thereof, and stretching is performed simultaneously. Therefore, the influence of one stretched part on the other stretched part is substantially the same as each other and is not affected by environmental changes over time. For this reason, the symmetry of the shape of one extending portion and the other extending portion can be improved. Therefore, it is possible to manufacture a parison with good quality and, consequently, a balloon without requiring complicated work. Moreover, by heating and extending | stretching simultaneously, compared with the case where it performs sequentially, the time which manufacture requires can be shortened and productivity can also be improved.

The parison manufacturing apparatus according to the second aspect of the present invention is:
A device for manufacturing a parison having extended portions at both ends of a straight body portion for manufacturing a balloon used for a balloon catheter,
A pair of fixing mechanisms for releasably fixing both ends of a straight tubular parison tube;
A pair of heating molds for simultaneously heating a part on one end side and a part on the other end side of the tube for parison fixed to the fixing mechanism respectively in a non-contact manner;
A stretching mechanism that simultaneously urges the pair of fixing mechanisms so as to be spaced apart from each other to stretch the parison tube.

The parison manufacturing apparatus according to the second aspect of the present invention provides a parison manufacturing apparatus that can suitably implement the parison manufacturing method according to the first aspect of the present invention.

FIG. 1 is a front view of a parison tube as a base material for producing a parison according to an embodiment of the present invention. FIG. 2 is a front view of a parison manufactured by heating and stretching the parison tube shown in FIG. FIG. 3 is a front view of an IABP balloon manufactured by biaxial stretch blow molding of the parison shown in FIG. FIG. 4 is a cross-sectional view of an IABP balloon catheter manufactured using the IABP balloon shown in FIG. FIG. 5 is a diagram showing a process for manufacturing a parison according to an embodiment of the present invention. FIG. 6A is a front view illustrating a schematic configuration of a parison manufacturing apparatus suitable for performing the parison manufacturing process illustrated in FIG. 5. FIG. 6B is a front view showing the parison manufacturing apparatus shown in FIG. 6A during heating and stretching. FIG. 7A is a diagram illustrating a configuration of a chuck mechanism that configures the parison manufacturing apparatus illustrated in FIG. 6A. FIG. 7B is a diagram showing a state in the middle of fixing one end of the parison tube to the chuck mechanism shown in FIG. 7A. FIG. 7C is a diagram showing a state where one end of the parison tube is fixed to the chuck mechanism shown in FIG. 7A. FIG. 7D is a view showing a modification of the chuck mechanism shown in FIG. 7A. FIG. 8A is a front view showing a configuration in a state where heating blocks of a heating mold constituting the parison manufacturing apparatus shown in FIG. 6A are separated. FIG. 8B is a side view of the heating mold shown in FIG. 8A. FIG. 8C is a bottom view of the heating block above the heating mold shown in FIG. 8A or a plan view of the lower heating block. FIG. 8D is a front view showing a state in which the heating block of the heating mold shown in FIG. 8A is brought into contact. FIG. 8E is a side view of the heating mold shown in FIG. 8D. FIG. 9 is a block diagram showing a configuration of a control system of the parison manufacturing apparatus shown in FIG. 6A.

Hereinafter, as an embodiment of the present invention, a case where a balloon included in a balloon catheter used for IABP (intra-aortic balloon pumping) is manufactured will be described as an example with reference to the drawings.

First, the parison tube 1 as a base material for manufacturing the parison according to the present embodiment will be described. As shown in FIG. 1, the parison tube 1 is a straight tube having a diameter that is substantially constant in the axial direction from one end to the other end.

As the material of the tube 1 for parison, a thermoplastic resin is used, and it is preferable that it is a material excellent in the bending fatigue resistance of the IABP balloon finally produced using this, for example, polyurethane, polyethylene, polyamide Polyamide elastomers, polyesters, and the like can be used, and those made of polyurethane are particularly preferable because they have a high ability to inhibit thrombus generation and high wear resistance.

Although the manufacturing method of the tube 1 for parison is not specifically limited, what was manufactured by extrusion molding can be used. The parison tube 1 has an axial dimension of about 50 to 400 mm, an outer diameter of about φ1 to 8 mm, and a wall thickness of about 0.1 to 1.0 mm.

As shown in FIG. 2, the parison (balloon parison) 2 is manufactured by heating and stretching the vicinity of both ends of the above-described parison tube as a base material, and the diameter thereof is substantially constant in the axial direction. It is a double-end stretched tube in which stretched portions (stretch portions) are disposed at both ends of a large diameter straight body portion (unstretched portion) 2a. The extending portions at both ends respectively have a transition portion 2b whose diameter gradually decreases and a small-diameter straight body portion 2c whose diameter hardly changes.

The axial dimension of the large diameter straight body 2a of the parison 2 is about 20 to 200 mm, and the axial dimension of the transition part 2b is about 2 to 50 mm. The outer diameter of the large diameter straight body portion 2a is about the same as the outer diameter of the parison tube 1, and the outer diameter of the small diameter straight body portion 2c is about φ0.2 to 3.0 mm.

As shown in FIG. 3, the balloon (IABP balloon) 3 manufactured using the above-described parison 2 gradually increases in diameter at both ends of the straight body portion 3a whose diameter is substantially constant in the axial direction. A cone portion (shoulder portion) 3b that decreases to a minimum and a neck portion 3c having a diameter that is substantially constant in the axial direction and smaller than that of the straight body portion 3a are arranged. The balloon 3 is manufactured by biaxial stretch blow molding. The straight barrel portion 3a of the balloon 3 is in the large diameter straight barrel portion 2a of the parison 2, the cone portion 3b of the balloon 3 is in the transition portion 2b of the parison 2, and the neck portion 3c of the balloon 3 is in the small diameter straight barrel portion 2c of the parison 2. It roughly corresponds.

IABP balloon catheter 4 as a final product manufactured using the above-described balloon 3 is configured as shown in FIG. The balloon 3 of the IABP balloon catheter 4 expands and contracts in accordance with the heart beat. The balloon 3 is formed of a cylindrical balloon film having a film thickness of about 20 to 200 μm. In the present embodiment, the shape of the balloon membrane in the expanded state is a cylindrical shape, but is not limited thereto, and may be a polygonal cylindrical shape.

The outer diameter and length of the balloon 3 for IABP are set according to the inner volume of the balloon 3, which has a great influence on the assist effect of the cardiac function, the inner diameter of the arterial blood vessel, and the like. The balloon 3 usually has an inner volume of 5 to 50 cc, an outer diameter when expanded of 8 to 20 mm, and a length of 80 to 270 mm.

The distal end of the balloon 3 is attached to the outer periphery of the distal end of the inner tube 42 through a short tube 41 or directly by heat fusion or adhesion. The proximal end of the balloon 3 is joined to the distal end of the catheter tube 44 via a contrast marker 43 made of a metal tube or the like or directly. Through the first lumen formed inside the catheter tube 44, the pressure fluid is introduced into or extracted from the balloon 3, and the balloon 3 is expanded or contracted. The balloon 3 and the catheter tube 44 are joined by heat fusion or adhesion with an adhesive such as an ultraviolet curable resin.

The distal end of the inner tube 42 projects farther from the distal end of the catheter tube 44. The inner tube 42 is inserted in the balloon 3 and the catheter tube 44 in the axial direction. The proximal end of the inner tube 42 is communicated with the second port 46 of the branch portion 45. A second lumen that does not communicate with the first lumen formed inside the balloon 3 and the catheter tube 44 is formed inside the inner tube 42.

When inserting the balloon catheter 4 into the artery, the second lumen of the inner tube 42 located in the balloon 3 is also used as a guide wire insertion lumen for conveniently inserting the balloon 3 into the artery. When the balloon catheter 4 is inserted into a body such as a blood vessel, the balloon 3 is wound around the outer periphery of the inner tube 42. The inner tube 42 is made of the same material as the catheter tube 44, for example.

The inner diameter of the inner tube 42 may be any diameter that allows the guide wire to be inserted, and is, for example, 0.15 to 1.5 mm, preferably 0.5 to 1 mm. The wall thickness of the inner tube 42 is preferably 0.1 to 0.4 mm. The total length of the inner tube 42 is determined according to the axial length of the balloon catheter 4 inserted into the blood vessel and is not particularly limited, but is, for example, about 500 to 1200 mm, preferably about 700 to 1000 mm.

The catheter tube 44 is preferably made of a material having a certain degree of flexibility. The inner diameter of the catheter tube 44 is preferably 1.5 to 4.0 mm, and the wall thickness of the catheter tube 44 is preferably 0.05 to 0.4 mm. The length of the catheter tube 44 is preferably about 300 to 800 mm.

The branch end 45 installed outside the patient's body is connected to the proximal end of the catheter tube 44. The branch portion 45 is formed separately from the catheter tube 44 and is fixed by means such as heat fusion or adhesion. The branch 45 includes a first port 48 for introducing or derivatizing pressure fluid to and from the first lumen in the catheter tube 44 and the balloon 3, and a second port 46 communicating with the second lumen of the inner tube 42. Is formed.

The first port 48 is connected to an unillustrated expansion / contraction drive device, and fluid pressure is supplied by the drive device so that the balloon 3 expands or contracts. The second port 46 is connected to a blood pressure fluctuation measuring device (not shown), and can measure a blood pressure fluctuation in the artery taken from the opening end 47 at the distal end of the balloon 3. Based on the blood pressure fluctuation measured by the blood pressure fluctuation measuring device, the driving device is controlled according to the heartbeat, and the balloon 3 is expanded and contracted in a short cycle of 0.4 to 1 second. .

Next, the manufacturing process of the parison 2 will be described with reference to FIG. First, the both ends of the unstretched straight tubular parison tube 1 are fixed (supported) in a substantially horizontal state, and as shown in FIG. 5A, the one end side and the other end of the parison tube 1 are fixed. Heating dies 51, 51 are disposed in the vicinity of each. Next, as shown by an arrow a1 in the figure, a heating process is performed in which the corresponding part is heated by the heating dies 51, 51 while rotating the parison tube 1 around its axis. The heating dies 51, 51 are not particularly limited, but non-contact type having a substantially cylindrical heating space (heating surface) having a larger diameter than the parison tube 1 can be used.

Thus, by rotating around the axis at the time of heating, when there is a temperature distribution on the heating surface of the heating dies 51, 51, or in a corresponding part of the parison tube 1 (heated by the heating dies 51, 51. Even when the distance between the outer periphery of the portion) and the heating surface of the heating mold 51 is not constant, the temperature distribution in the circumferential direction of the corresponding portion of the parison tube 1 can be made more uniform.

The heating temperature in the heating step is about 180 to 200 ° C., for example, when polyurethane is used as the base material of the parison tube 1, and the heating time is about 20 to 150 seconds. The rotation speed of the parison tube 1 around its axis is about 10 to 150 rpm. The heating range (the dimension in the axial direction of the heating surface) b1 by the heating dies 51, 51 is set to about 5 to 100 mm so that the portion to be the straight body portion (large diameter straight body portion 2a) of the parison 2 is not heated as much as possible. In addition, it is desirable to heat locally.

Next, as shown in FIG. 5 (B), by pulling both ends of the parison tube 1 as indicated by arrows a2 and a3 in the same figure, tension is applied to the parison tube 1, and the parison tube The extending | stretching process of extending | stretching the part heated at the said 1 heating process is implemented. The tension in the stretching process is about 2 to 20 N, and the stretching dimension b2 is about 5 to 200 mm.

Although not essential, the parison tube 1 may be rotated around its axis as indicated by an arrow a1 in FIG. By rotating the parison tube 1 about its axis even at the time of stretching, deformation of the heated portion of the parison tube 1 due to the action of gravity during stretching can be suppressed. Moreover, in this embodiment, when performing an extending | stretching process, although the heating by the heating metal molds 51 and 51 shall be stopped, you may carry out continuing heating.

When the stretching step is completed, a cooling step is then performed to fix the shape of the heated and stretched portion of the parison tube 1 as shown in FIG. The cooling step may be natural cooling in a state where heating by the heating dies 51, 51 is stopped or the heating dies 51, 51 and the parison tube 1 are separated from each other, or inside the parison tube 1. Alternatively, forced cooling may be performed by blowing a cooling gas to the outside. In the case of natural cooling, the cooling time is about 30 to 300 seconds when the temperature in the housing is 22 to 35 ° C.

Finally, the fixing (supporting) of both ends of the parison tube 1 that extends in the vicinity of both ends thereof is released, and at an appropriate portion of the extended portion (the position indicated by reference sign c1 in FIG. 5D), By cutting each, the completed parison (balloon parison) 2 shown in FIG. 2 can be obtained.

Next, a manufacturing apparatus for performing the above-described manufacturing process of the parison 2 will be described with reference to FIG. 6A. The parison manufacturing apparatus 5 includes a pair of chuck mechanisms (fixing mechanisms) 50 and 50, a pair of heating dies 51 and 51, a pair of rotating mechanisms 52 and 52, and a pair of stretching mechanisms 53 and 53. In addition, the parison manufacturing apparatus 5 includes a pair of tension detection sensors (tension detection means) 54 and 54, a support base 55, a casing 56, a pair of fans 57 and 57, a casing internal temperature detection sensor 58, and a control apparatus 59. Etc. are also provided.

The pair of chuck mechanisms 50 and 50 are means for supporting and fixing both ends of the parison tube 1 so as to be releasable in a state in which the parison tube 1 extends substantially horizontally. Since the chuck mechanisms 50 are substantially the same except that they are arranged symmetrically, only one chuck mechanism 50 (left side in FIG. 6A) will be described.

As shown in FIGS. 7A to 7C, the chuck mechanism 50 includes a substantially cylindrical positioning member having a positioning contact surface (contact portion) 50a, a substantially cylindrical pin member (pin portion) 50b, and a pair of pairs. A chuck member (chuck part) 50c is roughly provided.

A pin member 50b is erected on the contact surface 50a of the positioning member so as to be substantially perpendicular to the corresponding contact surface 50a and substantially coaxial with the positioning member. The pin member 50b is a member that is inserted into the lumen 1a at the end of the parison tube 1, and is slightly larger in diameter as long as it is substantially equal to the inner diameter of the lumen 1a of the parison tube 1 or does not hinder insertion. Is formed. Although not shown in the figure, the distal end portion of the pin member 50b is tapered or rounded at a portion on the distal end side so that the insertion into the lumen 1a of the parison tube 1 can be performed smoothly. It is preferable to have a tinged shape.

The abutting surface 50a of the positioning member is a surface with which the end surface of the parison tube 1 inserted into the inner cavity 1a of the pin member 50b abuts, and a stretching mechanism 53 described later is at a predetermined initial position. In the set state, the end surface of the parison tube 1 is brought into contact with the corresponding contact surface 50a, whereby the parison tube 1 can be positioned in the extending direction (left-right direction in FIG. 6A). ing.

The chuck members 50c and 50c are portions in which the pin member 50b is inserted into the inner lumen 1a of the end portion thereof, and the pin member 50b of the parison tube 1 in which the end surface thereof is in contact with the contact surface 50a of the positioning member. It is a member for fixing the end part of the tube 1 for parison by being pressed and clamped from the outside.

The chuck members 50c, 50c have a plurality of claw portions that are erected on the opposing portions in order to securely fix the parison tube 1. Further, in the present embodiment, the chuck members 50c and 50c are arranged at positions facing each other by 180 degrees, and although not illustrated, they are supported so as to be symmetrically close to and separated from each other, such as an air cylinder or the like. These driving means are configured to be close to or away from each other. The operation or stop of the chuck mechanisms 50, 50 (operation or stop of the driving means) is controlled by a control device 59, which will be described later, in accordance with an operator instruction.

As shown in FIG. 7A, the operator places one end portion of the parison tube 1 in the vicinity of one chuck member 50c, and as shown in FIG. 7B, the operator inserts a pin member into the lumen 1a on one end side of the parison tube 1. 50b is inserted, and the one end surface of the parison tube 1 is brought into contact with the contact surface 50a of the positioning member. In this state, by operating the drive means of the chuck members 50c, 50c, one end of the parison tube 1 can be fixed as shown in FIG. 7C. By performing the same operation on the other end portion of the parison tube 1, the parison tube 1 extends between the pair of chuck mechanisms 50 and 50 in a substantially horizontal direction and is fixedly disposed. be able to.

Since the parison tube 1 is sandwiched between the pin member 50b inserted into the lumen 1a and the chuck members 50c and 50c having a plurality of claws pressed against the pin member 50b, the lumen 1a of the parison tube 1 is crushed. Is difficult to occur, and it is possible to realize a strong fixation. For this reason, even when a high tensile load is applied, it is possible to withstand this. In addition, since the parison tube 1 can be accurately positioned, variation in quality between lots can be reduced.

In addition, although the number of chuck members 50c is two in the present embodiment, the number of chuck members 50c may be three or more, and they may be arranged radially at equal angular intervals. Although not essential, as shown in FIG. 7D, a gas passage 50d opened at the tip of the pin member 50b is formed, and nitrogen is introduced into the lumen 1a of the parison tube 1 through the gas passage 50d. It is preferable that an inert gas such as a gas can be supplied so as to suppress oxidation accompanying heating inside the parison tube 1.

6A, the chuck mechanisms 50 and 50 are supported and fixed to the rotation mechanisms 52 and 52, respectively, and the rotation mechanisms 52 and 52 are supported and fixed to the stretching mechanisms 53 and 53, respectively. The rotation mechanisms 52 and 52 are means for rotating the chuck mechanisms 50 and 50 so that the parison tube 1 supported and fixed therebetween rotates around its axis (see arrow a14). Since the rotation mechanisms 52 and 52 are substantially the same except that they are arranged symmetrically, only one rotation mechanism 52 (left side in FIG. 6A) will be described.

Although not shown in detail, the rotation mechanism 52 includes a disk-shaped rotation plate, a support member that rotatably supports the rotation plate, a rotation drive mechanism that rotates the rotation plate, and the like. Has been. The rotary plate is supported and fixed so that the positioning members of the chuck mechanism 50 described above are substantially coaxial with each other, and the support member is supported and fixed to the stretching mechanism 53. The rotational drive mechanism includes a drive motor (servo motor or the like) and a power transmission mechanism (timing belt, pulley, gear, or the like). The rotation drive mechanism is controlled by a control device 59, which will be described later, for its operation, stop, rotation direction, rotation speed, and the like. The rotation speed of the rotation mechanism 52 can be arbitrarily set in the range of about 0 to 150 rpm.

By operating the rotation mechanisms 52 and 52 in a state where both ends of the parison tube 1 are fixed to the chuck mechanisms 50 and 50, both can rotate synchronously so that the parison tube 1 can be rotated at a desired rotation speed. It has become.

The stretching mechanisms 53, 53 move or urge one of the pair of chuck mechanisms 50, 50 so as to be separated from the other, respectively, to the parison tube 1 whose both ends are fixed to the chuck mechanisms 50, 50. Means for applying tension. Since the extending mechanisms 53 and 53 are substantially the same except that they are arranged symmetrically, only one extending mechanism 53 (left side in FIG. 6A) will be described.

Although not shown in detail in the drawing mechanism 53, the movable member 53a and the movable member 53a are supported so as to be movable (slidable) in the left-right direction (see arrow a16) in the drawing, and the movable member 53a is linearly supported. The linear drive mechanism 53b etc. to be moved is provided.

The support member of the rotation mechanism 52 described above is supported and fixed to the movable member 53a, and the linear drive mechanism 53b of the stretching mechanism 53 is supported and fixed to the support base 55. The linear drive mechanism 53b includes a drive motor (such as a servo motor) and a ball screw mechanism that converts the rotational motion of the drive motor into linear motion. The linear drive mechanism 53b is not limited to such a configuration, and may be a rack and pinion mechanism, a linear motor, or the like. The linear drive mechanism 53b is controlled in its operation, stop, moving speed, moving direction, and the like by a control device 59 described later.

With the stretching mechanisms 53 and 53 set to predetermined initial positions, both ends of the parison tube 1 are fixed to the chuck mechanisms 50 and 50, and the stretching mechanisms 53 and 53 are operated, whereby the movable members 53a and 53a are moved. Both move synchronously (or try to move) in directions away from each other, and a desired tension can be applied to the parison tube 1.

Each stretching mechanism 53, 53 has a tension detection sensor (tension detection means) 54 for detecting the tension generated in the parison tube 1. For example, a load cell can be used as the tension detection sensor 54. In the present embodiment, a power transmission member 53c is provided in parallel to be separated from the movable member 53a in the moving direction, and a coil spring (not shown) and a tension detection sensor 54 are provided between the movable member 53a and the power transmission member 53c. The driving force of the linear drive mechanism 53b is transmitted to the movable member 53a via the power transmission member 53c. The detection value of the tension detection sensor 54 is input to the control device 59, and the thrust by the linear drive mechanism 53b is controlled by the control device 59 so that an appropriate preset tension is applied.

The heating dies 51, 51 have a part on one end side (a part to be an extension part) and a part on the other end side (an extension part) This is a means for heating the portion to be formed in a non-contact manner. The heating dies 51, 51 are disposed between the chuck mechanisms 50, 50 and spaced apart from each other in the left-right direction (the direction in which the parison tube 1 extends) in FIG. Since these heating molds 51 and 51 have substantially the same configuration, only one heating mold 51 (left side in FIG. 6A) will be described.

As shown in FIGS. 8A to 8E, the heating mold 51 has a pair of upper and lower heating blocks 51a and 51b each made of a metal material such as beryllium copper. The heating blocks 51a and 51b are moved up and down synchronously so as to be close to and away from each other in the vertical direction (see arrow a11 in FIG. 6A) by the lifting mechanism 51c.

Although not shown in detail, the elevating mechanism 51c includes a slide mechanism that holds the heating blocks 51a and 51b so that the heating blocks 51a and 51b can be slid upward and downward, a servo motor for moving the heating blocks 51a and 51b up and down, a ball screw, and the like. Drive mechanism. In the present embodiment, the heating blocks 51a and 51b are configured so that both move symmetrically and are separated from each other, but one (for example, the lower heating block 51b) is fixed, Only the other (for example, the upper heating block 51a) may be configured to move up and down, or vice versa.

A substantially semi-cylindrical inner wall surface (heating surface 51d) is formed on the lower surface of the upper heating block 51a and the upper surface of the lower heating block 51b, and the lower surface of the upper heating block 51a and the lower heating block 51b When the upper surface comes into contact, the semi-cylindrical heating surfaces 51d and 51d cause the left and right direction (the direction in which the parison tube 1 whose both ends are supported and fixed to the chuck mechanisms 50 and 50 extend). , The central axis extends, and a substantially cylindrical heating space opened at both ends thereof is defined.

Although not shown, each heating block 51a, 51b incorporates a heater that generates heat when energized and a mold temperature detection sensor (for example, a thermocouple) that detects the temperature of the heating block 51a, 51b. The control device 59 controls energization to the heater based on the detection value by the mold temperature detection sensor (see reference numeral 59c in FIG. 9), and is a substantially circle defined by the heating surfaces 51d and 51d of the heating blocks 51a and 51b. The columnar heating space is heated so as to have an appropriate temperature. The number of heaters and mold temperature detection sensors provided in each of the heating blocks 51a and 51b may be single or plural, but a plurality is more preferable because the temperature distribution on the heating surfaces 51d and 51d can be made more uniform. .

The inner diameter of the substantially cylindrical heating space defined by the heating surfaces 51d and 51d of the heating blocks 51a and 51b is separated from the outer periphery of the parison tube 1 disposed through the inside by a predetermined dimension. The diameter is set larger than the outer diameter of the parison tube 1 so that it can be heated without contact. Specifically, the inner diameter of the substantially cylindrical heating space defined by the heating surfaces 51d and 51d of the heating blocks 51a and 51b is set to about 2 to 12 mm.

When both ends of the parison tube 1 are supported and fixed to the pair of chuck mechanisms 50, 50, as shown in FIGS. 8A and 8B, the upper heating block 51a is set upward (see arrow a12) and the lower heating block is set. 51b is moved downward (see arrow a13) and separated from each other to be in an open state. When the portions near both ends of the parison tube 1 are heated, as shown in FIGS. 8D and 8E, the upper heating block 51a is downward (see arrow a13) and the lower heating block 51b is upward (arrow a12). And the lower surface of the upper heating block 51a and the upper surface of the lower heating block 51b are brought into contact with each other to be in a closed state. When removing the parison tube 1 from the chuck mechanisms 50, 50, as shown in FIGS. 8A and 8B, the upper heating block 51a is moved upward (see arrow a12) and the lower heating block 51b is moved downward (see This can be done by moving to the arrow a13) and making it open.

Returning to FIG. 6A, the pair of stretching mechanisms 53, 53 (linear drive mechanisms 53b, 53b) and the pair of heating dies 51, 51 (elevating mechanisms 51c, 51c) holding the chuck mechanism 50 and the rotating mechanism 52 are supported by a support base. The entirety of these components is housed in a housing 56. As the housing 56, a frame made of a metal or the like and a transparent panel (for example, an acrylic plate) attached thereto can be used. Although not shown, the casing 56 is provided with an openable / closable door for manually fixing or removing the parison tube 1 with respect to the chuck mechanisms 50, 50, or for other maintenance. Yes. A plurality of intake and exhaust (exhaust in this embodiment) fans 57 and 57 and an in-casing temperature detection sensor 58 for detecting the temperature in the casing 56 are attached to the casing 56.

Next, a control system of the above-described parison manufacturing apparatus will be described with reference to FIG. The control device 59 includes input means 59a and display means 59b. The input means 59a includes buttons for operating or releasing the chuck mechanisms 50, 50, an emergency stop button, other buttons, a keyboard for selecting functions and inputting various setting values, and the like. The display means 59b includes a liquid crystal monitor and various indicators.

When manufacturing the parison, first, the operator manually sets the unstretched parison tube 1 to the chuck mechanisms 50 and 50 at both ends thereof. At this time, as shown in FIG. 6A, the stretching mechanisms 53 and 53 are set at predetermined initial positions, and the heating dies 51 and 51 are in a state where the heating blocks 51a and 51b are separated (open). It has become. Next, the operation buttons of the chuck mechanisms 50 and 50 are pressed to support and fix the parison tube 1.

When it is confirmed that the ends of the parison tube 1 are fixed normally, the operator performs a predetermined operation (for example, presses a start button for heating and stretching), thereby performing a series of steps for manufacturing the parison. Operation starts. The control device 59 automatically controls each part in accordance with a control sequence previously selected by the operator. Note that this operation may be omitted, and a series of controls including the operation of fixing both ends of the above-described parison tube 1 may be started by pressing the operation buttons of the above-described chuck mechanisms 50 and 50.

An example of a control sequence by the control device 59 will be described. First, the stretching mechanisms 53 and 53 are driven so as to be separated from each other so that both ends of the parison tube 1 are supported and fixed to the chuck mechanisms 50 and 50 in advance. The set tension (initial tension) is applied and the state is maintained. The tension generated in the parison tube 1 is detected by a tension detection sensor 54. Based on the detected value, the stretching mechanisms 53 and 53 are controlled so as to have a preset initial tension, and the initial tension is set. After reaching, the feedback control is performed so that the tension becomes constant.

The initial tension is appropriately determined so that the slack of the parison tube 1 supported at both ends by the chuck mechanisms 50 and 50 (the difference in height between the central portion in the axial direction of the tube and the fixed portions at both ends) is within an allowable range. Set to the correct value. If the initial tension is too small, the slackness increases, and when placed in the heating space of the heating mold 51, there is a risk of contact with the inner wall surface (heating surface 51d) and melting, or uneven heating. It may be a cause. On the other hand, if the initial tension is too large, the slackness is reduced and the above problem can be solved. However, the heating portion of the parison tube 1 is unnecessarily stretched during the heating by the heating mold 51 and is manufactured. In addition, the unevenness of the transition part 2b of the parison 2 may not be uniform (the inclination becomes two steps), which may cause stretching unevenness. For this reason, the initial tension is set to an appropriate value that both of these allow. The initial tension can be about 1 to 10N. In this embodiment, since the tension generated in the parison tube 1 can be detected in real time by the tension detection sensor 54, the initial tension can be accurately maintained constant at a desired value, and the fluctuation of the initial tension can be maintained. It is possible to reduce the occurrence of stretching unevenness.

Next, as shown in FIG. 6B, the elevating mechanisms 51c and 51c of the heating molds 51 and 51 are operated, the upper heating block 51a is lowered (see arrow a13 in the figure), and the lower heating block 51b is raised. Then (see arrow a12 in the figure), the portions to be stretched in the vicinity of both ends of the parison tube 1 are defined by the heating surfaces 51d and 51d of the heating blocks 51a and 51b. It arrange | positions in the heating space formed (refer also FIG. 8D and FIG. 8E).

Next, energization is performed to the heaters of the heating molds 51 and 51, and heat generation is started. The energization of the heaters of the heating molds 51 and 51 may be performed before the heating blocks 51a and 51b are closed. The temperatures of the heating molds 51 and 51 are detected by a mold temperature detection sensor 59c, and energization of the heater is controlled so as to be a predetermined temperature set in advance. Simultaneously or before and after the operation of the heating dies 51, 51, synchronous rotation by the rotation mechanisms 52, 52 is started (see arrow a15), and the rotation is maintained at a predetermined rotation speed (rpm). Note that the rotation direction of the rotation mechanisms 52, 52 may be opposite to the arrow a15.

When a predetermined time has elapsed from the start of heating (or after reaching a predetermined temperature), the heating and rotation are stopped, and the stretching mechanisms 53 and 53 are moved away from each other ( The parison tube 1 is stretched (see arrows a17 and a18). The tension generated in the parison tube 1 is detected by a tension detection sensor 54, and the moving speed of the linear drive mechanisms 53b and 53b by the stretching mechanisms 53 and 53 is controlled based on the detected value. In addition, you may continue a heating and / or rotation during extending | stretching.

When the preset stretching length (stretch length) is reached, the movement of the linear drive mechanisms 53b, 53b of the stretching mechanisms 53, 53 is stopped, and this state is maintained for a preset predetermined time. The parison tube 1 is cooled. Thereby, the shape of the tube 1 for parison by which the vicinity part of the both ends was extended is fixed. The rotation may be continued or re-executed during cooling. If cooling for a predetermined time has been performed, the operator is notified that a series of operations has been completed, and this sequence is completed. The end notification can be displayed on an indicator or the like of the display means 59b, or can be made with a buzzer or the like.

When a series of sequences is completed, the operator depresses the release buttons of the chuck mechanisms 50 and 50 to release the fixing of both ends of the parison tube 1 in which the portions near the both ends are extended. Remove this at work. Note that during these series of operations, the temperature in the casing 56 is detected by the temperature detection sensor 58 in the casing, and the fans 57 and 57 are activated or stopped based on the detected value, whereby the casing 56 is detected. The temperature in the body 56 is controlled to be constant. Further, the releasing operation of the chuck mechanisms 50, 50 may be omitted, and this operation may be included in a series of sequences.

Finally, the parison 2 as a completed body shown in FIG. 2 is obtained by manually cutting an appropriate portion of the stretched portion of the tube 1 for parison in which the vicinity of both ends is stretched and cutting off both ends. Obtainable.

According to the embodiment described above, a part of one end side and a part of the other end side of the parison tube 1 are simultaneously heated by the heating dies 51, 51, and tension is applied to the both ends by the stretching mechanisms 53, 53. Thus, the one end side and the other end side can be stretched under substantially the same stretching conditions, and the symmetry of the shape between the one end side and the other end side of the parison 2 is improved. be able to. Therefore, it is possible to manufacture the parison 2 having a good quality without requiring a complicated operation, and thus to manufacture the balloon 3 having a high quality. Moreover, since it heats and extends | stretches simultaneously, manufacturing (processing) time can be shortened and productivity can also be improved.

The embodiment described above is described for facilitating understanding of the present invention, and is not described for limiting the present invention. Therefore, each element disclosed in the above-described embodiment is intended to include all design changes and equivalents belonging to the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Tube for parison 2 ... Parison 2a ... Large diameter straight body part 2b ... Transition part 2c ... Small diameter straight body part 3 ... Balloon for IABP 3a ... Straight body part 3b ... Conical part 3c ... Neck part 4 ... Balloon catheter for IABP 5 ... Parison manufacturing equipment 50 ... Chuck mechanism (fixing mechanism)
50a: Contact surface of positioning member 50b ... Pin member 50c ... Chuck member 51 ... Heating die 51a, 51b ... Heating block 51c ... Lifting mechanism 51d ... Heating surface 52 ... Rotating mechanism 53 ... Extending mechanism 53a ... Movable member 53b ... Linear Drive mechanism 53c ... Power transmission member 54 ... Tension detection sensor 55 ... Support base 56 ... Case 57 ... Fan 58 ... In-case temperature detection sensor 59 ... Control device 59a ... Input means 59b ... Display means 59c ... Die temperature detection sensor

Claims (2)

A method for producing a parison having stretched portions at both ends of a straight body portion for producing a balloon used for a balloon catheter,
A heating step of simultaneously heating a part of one end side and a part of the other end side of the straight tubular parison tube;
A parison manufacturing method comprising: applying a tension to both ends of the parison tube and simultaneously stretching a portion heated in the heating step. A device for manufacturing a parison having extended portions at both ends of a straight body portion for manufacturing a balloon used for a balloon catheter,
A pair of fixing mechanisms for releasably fixing both ends of a straight tubular parison tube;
A pair of heating molds for simultaneously heating a part on one end side and a part on the other end side of the tube for parison fixed to the fixing mechanism respectively in a non-contact manner;
A parison manufacturing apparatus comprising: a stretching mechanism that simultaneously biases the pair of fixing mechanisms so as to be separated from each other and stretches the parison tube.

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