JPWO2018181323A1 - Parison manufacturing method and parison manufacturing apparatus - Google Patents

Abstract

A method for manufacturing a parison having extended portions at both ends of a straight body portion, for manufacturing a balloon used for a balloon catheter, wherein the one end side and the other end side have a symmetrical shape, wherein a straight tubular parison tube is used. A heating step (A) in which a part of one end and a part of the other end are simultaneously heated, and a tension is applied to both ends of the parison tube 1 (arrows a2 and a3) to be heated in the heating step. And a stretching step (B) of simultaneously stretching the bent portions.

Description

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

  IABP (intra-aortic balloon pumping), which assists cardiac function by inserting a balloon catheter into the aorta and expanding and deflating the balloon in accordance with the heartbeat, has been performed as treatment for cardiac function deterioration. The IABP balloon catheter used for IABP is inserted from a femoral artery or the like, and used in a state where the balloon is placed in the descending thoracic aorta.

  In a balloon used in such an IABP balloon catheter, cone portions (shoulder portions) each having a tapered shape are arranged at both ends of a straight body portion, and a straight body neck portion is provided at a tip of each cone portion. Each has a disposed shape. The balloon is worn by attaching the neck to the outer surface of the catheter sheath.

  Such a balloon is manufactured by biaxially stretch-blowing a parison (tube) formed into a tubular shape by extrusion. As a parison manufacturing technique for this purpose, not a IABP balloon catheter but a PTCA (angioplasty) balloon catheter, which is disclosed in Patent Document 1 is known.

  In this technique, in order to improve the uniformity of the film thickness of the balloon, both ends of the parison used in the blow molding have different diameters (small diameters) than the straight body portion. . According to Patent Literature 1, the two-end tubes with different diameters are formed by alternately forming a thin portion and a thick portion by appropriately changing and controlling extrusion conditions by an extruder and take-off conditions by a take-off device during extrusion molding. , Has been manufactured.

  As another method of manufacturing such a tube having different diameters at both ends, a method of heating and stretching portions near both ends of a tube formed into a straight tube by extrusion molding has been put to practical use. In this method, a part of one end of a tube formed into a straight tube is heated by a heating mold, tension is applied to both ends of the tube, the heated part on one end is stretched, and then cooled. Next, a part of the other end of the tube is similarly heated by a heating mold, tension is applied to both ends of the tube, and the heated part on the other end is stretched and then cooled.

  As described above, conventionally, after performing the first stretching in which a part of one end of the tube is heated, stretched and cooled, the second stretching in which the other end is partially heated, stretched and cooled 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.). Here, it is preferable that the one end side and the other end side of the balloon in the longitudinal direction are symmetrical to each other, and therefore, it is preferable that the parison is also symmetrical.

  However, when the one end side and the other end side are sequentially stretched as in the related art, the second stretch has an effect of the portion stretched by the first stretch, and the environmental conditions (atmosphere) over time. Temperature or the like), 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 become symmetrical with each other. There was a case. Although it is theoretically possible to make the setting conditions of the second stretching different from the setting conditions of the first stretching (adjusted appropriately) so that they are symmetrical to each other, it is theoretically possible. In practice, finding the optimum conditions requires a very complicated operation, and is not practical.

JP 2001-321444A

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

The parison manufacturing method according to the first aspect of the present invention includes:
For manufacturing a balloon used for a balloon catheter, a method for manufacturing a parison having an extended portion at both ends of a straight body portion,
A heating step of simultaneously heating a part of one end and a part of the other end of the straight tubular parison tube,
A stretching step of applying tension to both ends of the parison tube to simultaneously stretch portions heated in the heating step.

  In the method for manufacturing a parison according to the first aspect of the present invention, a part of one end of the parison tube and a part of the other end of the parison tube are simultaneously heated, tension is applied to both ends thereof, and the two parts are simultaneously stretched. Therefore, the effect of one extending portion on the other extending portion 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 extended part and the other extended part can be improved. Therefore, it is possible to manufacture a high-quality parison and, eventually, a balloon without requiring a complicated operation. Further, by performing heating and stretching at the same time, the time required for production can be reduced and productivity can be improved as compared with the case of performing heating and stretching simultaneously.

The parison manufacturing apparatus according to the second aspect of the present invention includes:
For manufacturing a balloon used in a balloon catheter, a parison manufacturing apparatus having an extending portion at both ends of a straight body portion,
A pair of fixing mechanisms for releasably fixing both ends of the straight tubular parison tube,
A pair of heating molds for simultaneously heating a part of one end and a part of the other end of the parison tube fixed to the fixing mechanism in a non-contact manner, respectively.
A stretching mechanism that simultaneously urges the pair of fixing mechanisms so as to be separated from each other and extends the parison tube.

  According to the parison manufacturing apparatus according to the second aspect of the present invention, there is provided a parison manufacturing apparatus capable of suitably performing 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 manufacturing a parison according to one 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 biaxially stretch blow molding 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 parison manufacturing process according to an embodiment of the present invention. FIG. 6A is a front view showing a schematic configuration of a parison manufacturing apparatus suitable for performing the parison manufacturing process shown in FIG. FIG. 6B is a front view showing the parison manufacturing apparatus shown in FIG. 6A during heat stretching. FIG. 7A is a diagram illustrating a configuration of a chuck mechanism included in the parison manufacturing apparatus illustrated in FIG. 6A. FIG. 7B is a diagram showing a state in which one end of the parison tube is being fixed 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 the configuration of the parison manufacturing apparatus shown in FIG. 6A in a state where the heating blocks of the heating mold are separated from each other. FIG. 8B is a side view of the heating mold shown in FIG. 8A. FIG. 8C is a bottom view of the upper heating block or a plan view of the lower heating block shown in FIG. 8A. FIG. 8D is a front view illustrating a state where the heating block of the heating mold illustrated in FIG. 8A is brought into contact with the heating block. 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 provided in a balloon catheter used for IABP (intra-aortic balloon pumping) will be described as an example with reference to the drawings.

  First, a 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 whose diameter is substantially constant in the axial direction from one end to the other end.

  As a material for the parison tube 1, a thermoplastic resin is used, and it is preferable that the IABP balloon finally manufactured using the resin is a material excellent in bending fatigue resistance. For example, polyurethane, polyethylene, polyamide Polyamide elastomer, polyester, etc. can be used. In particular, those formed of polyurethane are preferable because they have high thrombus generation inhibiting ability and high abrasion resistance.

  The method for manufacturing the parison tube 1 is not particularly limited, but a tube manufactured by extrusion can be used. The axial dimension of the parison tube 1 is about 50 to 400 mm, the outer diameter is about 1 to 8 mm, and the wall thickness is about 0.1 to 1.0 mm.

  As shown in FIG. 2, the parison 2 (balloon parison) manufactured by using the above-described parison tube as a base material and heat-stretching portions near both ends thereof has a substantially constant diameter in the axial direction, as shown in FIG. This is a double-ended tube in which stretched portions (stretched portions) are arranged at both ends of a large-diameter straight body portion (unstretched portion) 2a. The extending portions at both ends 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 part 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 2a is approximately the same as the outer diameter of the parison tube 1, and the outer diameter of the small-diameter straight body 2c is about φ0.2 to 3.0 mm.

  As shown in FIG. 3, a balloon (IABP balloon) 3 manufactured using the above-described parison 2 has a diameter gradually increasing at both ends of a straight body 3a whose diameter is substantially constant in the axial direction. And a neck portion 3c whose diameter is substantially constant in the axial direction and whose diameter is smaller than that of the straight body portion 3a. The balloon 3 is manufactured by biaxial stretch blow molding. The straight body 3a of the balloon 3 is on the large-diameter straight body 2a of the parison 2, the cone 3b of the balloon 3 is on the transition 2b of the parison 2, and the neck 3c of the balloon 3 is on the small-diameter straight body 2c of the parison 2. It corresponds roughly.

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

  The outer diameter and the length of the IABP balloon 3 are set according to the inner volume of the balloon 3 which greatly affects the assisting 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 via 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 the contrast marker 43 made of a metal tube or the like or directly. Through a first lumen formed inside the catheter tube 44, a pressure fluid is introduced or drawn into the balloon 3, and the balloon 3 expands or contracts. The bonding between the balloon 3 and the catheter tube 44 is performed by heat fusion or adhesion with an adhesive such as an ultraviolet curing resin.

  The distal end of the inner tube 42 projects farther than the distal end of the catheter tube 44. The inner tube 42 is inserted through the inside of the balloon 3 and the catheter tube 44 in the axial direction. The proximal end of the inner tube 42 communicates with the second port 46 of the branch portion 45. Inside the inner tube 42, a second lumen that is not communicated with the inside of the balloon 3 and the first lumen formed in the catheter tube 44 is formed.

  When the balloon catheter 4 is inserted 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 folded around the inner tube 42 and wound. The inner tube 42 is made of, for example, the same material as the catheter tube 44.

  The inner diameter of the inner tube 42 may be any diameter as long as the guide wire can be inserted, and is, for example, 0.15 to 1.5 mm, and preferably 0.5 to 1 mm. The 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, and 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 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 proximal end of the catheter tube 44 is connected to a bifurcation 45 that is located outside the patient's body. 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 discharging a 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. Are formed.

  The first port 48 is connected to an expansion / contraction driving device (not shown), and the driving device supplies fluid pressure 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 the fluctuation of the blood pressure in the artery taken in from the open end 47 at the distal end of the balloon 3. Based on the fluctuation of the blood pressure measured by the blood pressure fluctuation measuring device, the driving device is controlled in accordance with the heartbeat to expand and contract the balloon 3 in a short cycle of 0.4 to 1 second. .

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

  By rotating around the axis during heating in this way, when the heating surfaces of the heating dies 51, 51 have a temperature distribution, or in the corresponding portion of the parison tube 1 (the heating is performed by the heating dies 51, 51). Even when the distance between the outer periphery of the portion (part) 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, for example, about 180 to 200 ° C. 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 (dimension in the axial direction of the heating surface) b1 by the heating molds 51, 51 is set to about 5 to 100 mm so that the portion of the parison 2 that is to become the straight body (large-diameter straight body 2a) is not heated as much as possible. In addition, it is desirable to perform heating locally.

  Next, as shown in FIG. 5 (B), tension is applied to the parison tube 1 by pulling both ends of the parison tube 1 as shown by arrows a2 and a3 in FIG. (1) A stretching step of stretching a portion heated in the heating step is performed. The tension in the stretching step is about 2 to 20 N, and the stretching dimension b2 is about 5 to 200 mm.

  Note that, although not essential, the parison tube 1 may be rotated around its axis during the stretching process, as shown by an arrow a1 in FIG. By rotating the parison tube 1 around its axis also during stretching, deformation of a particularly heated portion of the parison tube 1 due to the action of gravity during stretching can be suppressed. In the present embodiment, when the stretching step is performed, the heating by the heating dies 51, 51 is stopped, but the heating may be performed while continuing.

  After 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. 5 (C). In the cooling step, natural cooling may be performed in a state in which heating by the heating dies 51, 51 is stopped or in a state in which the heating dies 51, 51 are separated from the parison tube 1, or the inside of the parison tube 1 may be cooled. Alternatively, a cooling gas may be blown to the outside to perform forced cooling. The cooling time is about 30 to 300 seconds when the temperature in the housing is 22 to 35 ° C. in the case of natural cooling.

  Lastly, the fixing (support) of both ends of the parison tube 1 with the portions near both ends extended is released, and at an appropriate portion of the extended portion (the position indicated by reference numeral c1 in FIG. 5D), By cutting each of them, a parison (parison for balloon) 2 as a completed body 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, 50, a pair of heating dies 51, 51, a pair of rotating mechanisms 52, 52, and a pair of stretching mechanisms 53, 53. In addition, the parison manufacturing apparatus 5 includes a pair of tension detection sensors (tension detection means) 54, 54, a support 55, a housing 56, a pair of fans 57, 57, a temperature detection sensor 58 in the housing, and a control device 59. Etc. are also provided.

  The pair of chuck mechanisms 50, 50 are means for releasably supporting and fixing both ends thereof in a state where the parison tube 1 is extended substantially horizontally. Since the chuck mechanisms 50 and 50 have substantially the same configuration except that they are symmetrically arranged, only the one (left side in FIG. 6A) chuck mechanism 50 will be described.

  7A to 7C, the chuck mechanism 50 includes a substantially cylindrical positioning member having a positioning contact surface (contact portion) 50a, a substantially columnar pin member (pin portion) 50b, and a pair of A chuck member (chuck portion) 50c is generally provided.

  On the contact surface 50a of the positioning member, a pin member 50b is erected substantially perpendicular to the corresponding contact surface 50a and substantially coaxially with the positioning member. The pin member 50b is a member to be inserted into the inner cavity 1a of the end of the parison tube 1, and has a diameter substantially equal to the inner diameter of the inner cavity 1a of the parison tube 1 or a slightly larger diameter as long as the insertion is not hindered. Is formed. Although not shown in the figure, the distal end of the pin member 50b has a tapered or rounded part at the distal end so that the parison tube 1 can be smoothly inserted into the lumen 1a. It is preferable to take a shape having the shape.

  The contact surface 50a of the positioning member is a surface on which the end surface of the parison tube 1 in which the pin member 50b is inserted into the lumen 1a at the end thereof is brought into contact. 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 (the left-right direction in FIG. 6A). ing.

  The pin members 50b of the parison tube 1 in which the pin members 50b are inserted into the lumens 1a at the ends of the chuck members 50c and 50c, and the end surfaces of the chuck members 50c and 50c abut on the contact surfaces 50a of the positioning members. Is a member for fixing the end of the parison tube 1 by being pressed against and sandwiched from the outside.

  The chuck members 50c, 50c have a plurality of claws erected at opposing portions to surely fix the parison tube 1. In the present embodiment, the chuck members 50c, 50c are arranged at positions facing each other by 180 degrees, and although not shown, are supported so as to be symmetrically close to and away from each other, and are provided with an air cylinder or the like. Are arranged to be close to or separated from each other by the driving means. The operation or stop of the chuck mechanisms 50, 50 (the operation or stop of the driving means) is controlled by a control device 59, which will be described later, according to an instruction of the operator.

  The operator arranges one end of the parison tube 1 near one of the chuck members 50c as shown in FIG. 7A, and inserts a pin member into the lumen 1a on one end side of the parison tube 1 as shown in FIG. 7B. 50b is inserted, and one end surface of the parison tube 1 is brought into contact with the contact surface 50a of the positioning member. By operating the driving means of the chuck members 50c, 50c in this state, one end of the parison tube 1 can be fixed as shown in FIG. 7C. The same operation is performed on the other end of the parison tube 1 so that the parison tube 1 extends substantially horizontally and is fixedly disposed between the pair of chuck mechanisms 50, 50. be able to.

  The parison tube 1 is sandwiched between the pin member 50b inserted into the lumen 1a and the chuck members 50c, 50c having a plurality of claws pressed against the outside thereof, so that the lumen 1a of the parison tube 1 is crushed. Hardly occurs, and a strong fixation can be realized. Therefore, even when a high tensile load is applied, it is possible to withstand this. Further, since the parison tube 1 can be accurately positioned, variation in quality between lots can be reduced.

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

  Returning to FIG. 6A, the chuck mechanisms 50, 50 are supported and fixed to rotating mechanisms 52, 52, respectively, and the rotating mechanisms 52, 52 are supported and fixed to stretching mechanisms 53, 53, respectively. The rotating mechanisms 52, 52 are means for rotating the chuck mechanisms 50, 50 such that the parison tube 1 supported and fixed between them rotates around its axis (see arrow a14). The rotation mechanisms 52, 52 have substantially the same configuration except that they are arranged symmetrically. Therefore, only one (left side in FIG. 6A) rotation mechanism 52 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 driving mechanism that rotates the rotation plate, and the like. Have been. The positioning member of the chuck mechanism 50 described above is supported and fixed to the rotating plate so as to be substantially coaxial with each other. The supporting member is supported and fixed to the stretching mechanism 53. The rotary drive mechanism includes a drive motor (servo motor, etc.) and a power transmission mechanism (timing belt, pulley, gear, etc.). The operation, stop, rotation direction, rotation speed, and the like of the rotation drive mechanism are controlled by a control device 59 described later. The rotation speed of the rotation mechanism 52 can be arbitrarily set within a range of about 0 to 150 rpm.

  By operating the rotation mechanisms 52, 52 in a state where both ends of the parison tube 1 are fixed to the chuck mechanisms 50, 50, both rotate synchronously, and 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 to be separated from the other, respectively, to the parison tube 1 whose both ends are fixed to the chuck mechanisms 50, 50. This is a means for applying tension. The stretching mechanisms 53, 53 have substantially the same configuration except that they are arranged symmetrically. Therefore, only one (left side in FIG. 6A) stretching mechanism 53 will be described.

  Although not shown in detail, the stretching mechanism 53 supports the movable member 53a and the movable member 53a so as to be movable (slidable) in the left-right direction (see arrow a16) in FIG. And a linear drive mechanism 53b for moving the optical disk.

  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 extension mechanism 53 is supported and fixed to the support table 55. The linear drive mechanism 53b includes a drive motor (such as a servomotor) and a ball screw mechanism that converts the rotational motion of the drive motor into a linear motion. Note that 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 operation, stop, moving speed, moving direction, and the like of the linear drive mechanism 53b are controlled by a control device 59 described later.

  With the stretching mechanisms 53, 53 set at predetermined initial positions, both ends of the parison tube 1 are fixed to the chuck mechanisms 50, 50, and the stretching mechanisms 53, 53 are operated, whereby the movable members 53a, 53a Both move synchronously in a direction in which they are separated from each other (or attempt to move), so that a desired tension can be applied to the parison tube 1.

  Each of the stretching mechanisms 53 has a tension detecting sensor (tension detecting means) 54 for detecting the tension generated in the parison tube 1. As the tension detection sensor 54, for example, a load cell can be used. In the present embodiment, a power transmission member 53c is arranged in parallel with 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 by the linear drive mechanism 53b is interposed and 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 control device 59 controls the thrust by the linear drive mechanism 53b so that an appropriate preset tension is applied.

  The heating dies 51, 51 have a part at one end (a part to be an extended part) and a part at the other end (a part to be an extended part) of the parison tube 1 whose both ends are supported and fixed to the chuck mechanisms 50, 50. (A part to be formed) in a non-contact manner. The heating dies 51, 51 are located between the chuck mechanisms 50, 50 and are spaced apart from each other in the left-right direction (the direction in which the parison tube 1 extends) in FIG. Since these heating dies 51, 51 have substantially the same configuration, only one (the left side in FIG. 6A) heating dies 51 will be described.

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

  Although not shown in detail, the elevating mechanism 51c has a slide mechanism for holding the respective heating blocks 51a and 51b so as to be slidable up and down, and a servomotor and a ball screw for driving the elevating and lowering of the heating blocks 51a and 51b. And a drive mechanism. In the present embodiment, the heating blocks 51a and 51b are configured to move symmetrically and to approach and separate 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 may be configured to perform the reverse.

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

  Although not shown, each of the heating blocks 51a and 51b has a built-in heater that generates heat when energized and a mold temperature detection sensor (for example, a thermocouple) that detects the temperature of the heating blocks 51a and 51b. The control device 59 controls the energization of the heater based on the value detected by the mold temperature detection sensor (see reference numeral 59c in FIG. 9), and forms a substantially circular shape defined by the heating surfaces 51d, 51d of the heating blocks 51a, 51b. The column-shaped heating space is heated to 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 of 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, 51d of the heating blocks 51a, 51b is set at a predetermined distance from the outer periphery of the parison tube 1 disposed therethrough. The diameter is set to be larger than the outer diameter of the parison tube 1 so that heating can be performed without contact. Specifically, the inner diameter of the substantially cylindrical heating space defined by the heating surfaces 51d, 51d of the heating blocks 51a, 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 moved upward (see arrow a12), and the lower heating block is moved downward. 51b is moved downward (see the arrow a13), separated from each other, and brought into an open state. When heating the portions near both ends of the parison tube 1, as shown in FIGS. 8D and 8E, the upper heating block 51a is moved downward (see arrow a13), and the lower heating block 51b is moved 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 bring them into 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 again moved upward (see the arrow a12), and the lower heating block 51b is moved downward (see arrow a12). This can be done by moving to (see arrow a13) and opening it.

  Returning to FIG. 6A, a pair of stretching mechanisms 53, 53 (linear drive mechanisms 53b, 53b) and a pair of heating dies 51, 51 (elevation mechanisms 51c, 51c) holding the chuck mechanism 50 and the rotation mechanism 52 are supported by a support base. These are fixed on a frame 55, and are entirely accommodated in a housing 56. As the housing 56, a housing in which a transparent panel (for example, an acrylic plate) is attached to a frame made of metal or the like can be used. Although not shown, the housing 56 is provided with an openable / closable door for manually fixing or removing the parison tube 1 to / from the chuck mechanisms 50, 50, or for performing other maintenance or the like. I have. The housing 56 is provided with a plurality of intake and exhaust (in this embodiment, exhaust) fans 57 and 57 and an in-housing temperature detection sensor 58 for detecting the temperature inside the housing 56.

  Next, a control system of the above-described parison manufacturing apparatus will be described with reference to FIG. The control device 59 includes an input unit 59a and a display unit 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 set values, and the like. The display means 59b includes a liquid crystal monitor, various indicators, and the like.

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

  After confirming that both ends of the parison tube 1 have been fixed normally, the operator performs a predetermined operation (for example, presses a start button of heating and stretching) to perform a series of operations for manufacturing the parison. The operation starts. The control device 59 automatically controls each unit according to a control sequence selected in advance by the operator. This operation may be omitted, and a series of controls including the operation of fixing both ends of the parison tube 1 described above may be started by pressing the operation buttons of the chuck mechanisms 50, 50 described above.

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

  The initial tension is appropriately set so that the slack of the parison tube 1 whose both ends are supported and fixed to the chuck mechanisms 50, 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. Is set to an appropriate value. If the initial tension is too small, the slack increases, and when placed in the heating space of the heating mold 51, there is a risk of melting by contact with the inner wall surface (heating surface 51d) or uneven heating. May cause. On the other hand, if the initial tension is too large, the slack is reduced, and the above-mentioned problem can be solved. In some cases, the transition portion 2b of the parison 2 has a non-uniform inclination (the inclination becomes two steps) and stretching unevenness may occur. For this reason, the initial tension is set to an appropriate value that allows both of these. The initial tension can be about 1 to 10N. In the present 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 at a desired value, and the initial tension can be changed. Can reduce the occurrence of stretching unevenness.

  Next, as shown in FIG. 6B, the elevating mechanisms 51c, 51c of the heating molds 51, 51 are operated, and the upper heating block 51a is lowered (see the arrow a13 in FIG. 6), and the lower heating block 51b is raised. Then (see arrow a12 in the figure) and abut against each other (close), portions to be extended near both ends of the parison tube 1 are defined by the heating surfaces 51d and 51d of the heating blocks 51a and 51b. It is arranged in the heating space to be formed (see also FIGS. 8D and 8E).

  Next, the heaters of the heating molds 51, 51 are energized, and heat generation is started. The heaters of the heating dies 51, 51 may be energized before the heating blocks 51a, 51b are closed. The temperatures of the heating molds 51, 51 are detected by a mold temperature detection sensor 59c, and energization of the heaters is controlled so as to reach a predetermined temperature. Simultaneously with 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 rotation is maintained at a predetermined rotation speed (rpm). The rotation directions of the rotation mechanisms 52, 52 may be opposite to the arrow a15.

  After the start of heating (or after reaching a predetermined temperature), when a preset predetermined time has elapsed, heating and rotation are stopped, and the stretching mechanisms 53, 53 are moved in a direction away from each other ( Arrows a17 and a18), the parison tube 1 is stretched. The tension generated in the parison tube 1 is detected by a tension detection sensor 54, and the moving speed of the linear driving mechanisms 53b, 53b by the stretching mechanisms 53, 53 is controlled based on the detected value. Note that heating and / or rotation may be continued during 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 parison tube 1 in which the portions near both ends are extended is fixed. The rotation may be continued or re-executed during the cooling. If the cooling has been performed for a predetermined time, the operator is notified that a series of operations has been completed, and the sequence ends. Note that the end notification can be displayed on an indicator or the like of the display means 59b, or can be made by a buzzer or the like.

  When a series of sequences is completed, the operator presses the release button of the chuck mechanism 50, 50 to release the fixing of both ends of the parison tube 1 whose portions near both ends are extended. Remove it by work. During a series of these operations, the temperature inside the housing 56 is detected by the temperature sensor 58 inside the housing, and based on the detected value, the fans 57 and 57 are operated or stopped, and The temperature in the body 56 is controlled to be constant. Further, the operation of releasing the chuck mechanisms 50, 50 may be omitted, and this operation may be included in a series of sequences.

  Finally, the parison tube 1 as a completed body shown in FIG. Obtainable.

  According to the above-described embodiment, a part of one end and a part of the other end of the parison tube 1 are simultaneously heated by the heating dies 51, 51, and tension is applied to both ends thereof by the stretching mechanisms 53, 53. As a result, the parison 2 can be stretched under substantially the same stretching conditions at one end and the other end, and the symmetry of the shape of the parison 2 at one end and the other end can be improved. be able to. Therefore, the parison 2 of good quality can be manufactured without any complicated work, and the balloon 3 having high quality can be manufactured. In addition, since heating and stretching are performed at the same time, manufacturing (processing) time can be reduced, and productivity can be improved.

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

DESCRIPTION OF SYMBOLS 1 ... Parison tube 2 ... Parison 2a ... Large diameter straight body part 2b ... Transition part 2c ... Small diameter straight body part 3 ... IABP balloon 3a ... Straight body part 3b ... Cone part 3c ... Neck part 4 ... IABP balloon catheter 5 ... Parison manufacturing equipment 50 ... Chuck mechanism (fixing mechanism)
50a ... Contact surface of positioning member 50b ... Pin member 50c ... Chuck member 51 ... Heating mold 51a, 51b ... Heating block 51c ... Elevating mechanism 51d ... Heating surface 52 ... Rotating mechanism 53 ... Stretching mechanism 53a ... Moving member 53b ... Straight line Driving mechanism 53c Power transmitting member 54 Tension detection sensor 55 Support base 56 Housing 57 Fan 58 Temperature sensor inside the housing 59 Control device 59a Input means 59b Display means 59c Mold temperature detection sensor

Claims (2)

For manufacturing a balloon used for a balloon catheter, a method for manufacturing a parison having an extended portion at both ends of a straight body portion,
A heating step of simultaneously heating a part of one end and a part of the other end of the straight tubular parison tube,
A stretching step of applying tension to both ends of the parison tube to simultaneously stretch portions heated in the heating step. For manufacturing a balloon used in a balloon catheter, a parison manufacturing apparatus having an extending portion at both ends of a straight body portion,
A pair of fixing mechanisms for releasably fixing both ends of the straight tubular parison tube,
A pair of heating molds for simultaneously heating a part of one end and a part of the other end of the parison tube fixed to the fixing mechanism in a non-contact manner, respectively.
And a stretching mechanism for simultaneously stretching the pair of fixing mechanisms so as to be separated from each other to extend the parison tube.

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