JP2012000944A - Resin rod pulling device and heat fixing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin rod pulling device and a heat fixing method which applies predetermined tension to a resin rod by a simple structure.SOLUTION: The resin rod pulling device 1 includes: a pair of grip means 7 for detachably gripping both ends 5 of a biodegradable resin rod 3; a supporting means 11 for movably supporting the pair of grip means 7 in a direction of relatively approaching or separating the grip means; a drive means 15 for operating an output part 13 in a direction of moving the pair of grip means 7; an elastic member 17 for connecting the output part 13 of the drive means 15 to the grip means 7; and a variable spacer 69 for regulating a space between the grip means 7 and the output part 13 of the drive means 15.

Description

  The present invention relates to a resin rod tensioning device that applies tension to a rod obtained by stretching a thermoplastic resin, and a heat fixing method.

  Conventionally, in order to produce a biodegradable resin rod used as a material for a surgical bone pin or the like, it is first obtained by heating to a temperature at which the polylactic acid, which is a crystalline raw material, is plasticized, and stretching it into a rod shape. A biodegradable resin rod is stretched to a desired length. The step of stretching the biodegradable resin rod is performed by immersing the biodegradable resin rod in an immersion liquid having a temperature close to the glass transition point of polylactic acid and applying a predetermined tension thereto. Subsequently, the biodegradable resin rod is thermally fixed, and a screw is formed by cutting the biodegradable resin rod after the relaxation process. A product obtained by sterilization by heating at a predetermined temperature is a product. Patent document 1 is disclosing the apparatus which heat-fixes a plastic molded product.

  The above heat setting removes the internal stress remaining on the biodegradable resin rod by immersing the biodegradable resin rod in an immersion liquid at a temperature equal to or higher than the crystallization peak temperature of polylactic acid and applying a predetermined tension thereto. Or a process for adjusting the crystal structure. The relaxation step is different from heat fixation in that the temperature of the immersion liquid is set to be equal to or lower than the crystallization peak temperature. The tension described above is generated by gripping both ends of the biodegradable resin rod with a pair of gripping means composed of a chuck or the like, and applying relatively opposite forces to these gripping means.

  However, the biodegradable resin rod contracts as the heat setting proceeds, and then begins to expand. When the biodegradable resin rod expands and contracts with its both ends fixed to a chuck or the like, the biodegradable resin rod warps. Such warpage causes a shake when the biodegradable resin rod is attached to and rotated by a main shaft such as a lathe, so that the processing accuracy of the screw cut into the biodegradable resin rod is impaired.

  In addition, in order to control the force applied to the gripping means based on the contraction rate or expansion rate of the biodegradable resin rod, the sensors for measuring the tension of the biodegradable resin rod and the operation of the gripping means are controlled. A control device such as a computer is indispensable. The addition of these leads to a complicated resin rod tensioning device and an increase in manufacturing cost. Moreover, when heat-fixing several biodegradable resin rods at once, it is not easy to control so that the tension | tensile_strength of all the biodegradable resin rods may become equal mutually.

JP-A-60-36125

  The present invention has been made in view of the above circumstances, and the object of the present invention is to apply a predetermined tension to the resin rod and to have a simple structure and a heat fixing method. Is to provide.

  The present invention provides a pair of gripping means for detachably holding both ends in the longitudinal direction of the resin rod, a support means for supporting the pair of gripping means movably in the longitudinal direction, and an output portion in the longitudinal direction. It is characterized by comprising driving means for operating and an elastic member for connecting at least one of the pair of gripping means to the output part of the driving means.

  The present invention also provides a pair of gripping means for detachably gripping both ends of the resin rod, a support means for movably supporting the pair of gripping means so as to be relatively close to each other, or the gripping means. Driving means for operating the output unit in the moving direction, a variable spacer for defining the distance between the output unit of the driving unit and the gripping unit to an extension length of the elastic member, and an output unit of the driving unit. An elastic member that connects at least one of the pair of gripping means, and the output portion of the driving means operates in the direction of moving the pair of gripping means relatively apart from each other through the elastic member. By pulling the means, tension is generated in the resin rod gripped at both ends by the pair of gripping means.

  Further, according to the present invention, the pair of gripping means includes a plurality of receiving members that receive the plurality of resin rods, a plurality of sandwiching members disposed above the plurality of receiving members, and the receiving member. And an opening / closing means for raising and lowering the sandwiching member, and the opening / closing means sandwiches the resin rod between the holding member and the sandwiching member by lowering the plurality of sandwiching members. The resin rod is released by raising the plurality of sandwiching members.

  Further, the present invention is characterized by comprising a detecting means for detecting an interval between the output part of the driving means and the gripping means connected to the output part by the elastic member.

  Further, the present invention includes an elevating unit that moves the pair of gripping units up and down, and a storage tank that is disposed below the pair of gripping units and stores an immersion liquid that conducts heat to a resin rod, and the pair of gripping units The means grips both ends of the resin rod, and the lifting means lowers the pair of gripping means to a height at which the resin rod sinks in the immersion liquid in the storage tank.

  Further, the present invention relates to a heat fixing method in which the resin rod is maintained at a constant temperature in a state where tension is generated in the resin rod by a pulling force in a direction in which both ends in the longitudinal direction of the resin rod are relatively separated from each other. A traction force is applied to at least one of both ends of the resin rod through an elastic member that expands and contracts in the longitudinal direction.

  Further, the present invention is characterized in that the temperature of the resin rod is kept constant in a gas or liquid that conducts heat to the resin rod.

  According to the resin rod tensioning apparatus according to the present invention, the output portion of the driving means operates in a direction that relatively separates the pair of gripping means, whereby tension is applied to the resin rod gripped at both ends by the pair of gripping means. The resin rod can be heat-set or relaxed satisfactorily. In addition, even if the entire length of the resin rod expands and contracts, the elastic member interposed between the output portion of the driving means and the gripping device expands and contracts accordingly, so that the resin rod does not warp. In this manner, a linear resin rod can be attached to a main shaft such as a lathe and an appropriate screw can be ground on the resin rod.

  In addition, since an unnecessary increase or decrease in the tension generated in the resin rod due to the expansion and contraction of the elastic member can be suppressed, the resin rod tensioning device can satisfactorily remove internal stress remaining in the resin rod or adjust its crystal structure. It can be carried out. For this reason, even if the resin rod is heated at the stage of sterilization, there is no deviation in the dimensions or the shape of the screw, so that the resin rod can satisfy the quality as a product. In addition, since sensors for measuring the tension of the resin rod and a computer for controlling the operation of the gripping means are unnecessary, the resin rod tensioning device is advantageous for simplifying the structure and reducing the manufacturing cost. It is.

  According to the resin rod tensioning apparatus of the present invention, the plurality of resin rods are respectively received by the plurality of receiving members, and the opening / closing means descends the plurality of sandwiching members, whereby the plurality of resin rods are received by the plurality of holding members. And a plurality of clamping members. In this state, just by operating the output unit as described above, the driving means can generate equal tension to all the resin rods, and all the resin rods can be uniformly heat-set or relaxed. The effects described here can be achieved by the resin rod tensioning device even if the overall lengths of the plurality of resin rods are different from each other due to errors in manufacturing. Further, since the opening / closing means raises the sandwiching member, the resin rod can be quickly released from between the holding member and the sandwiching member, so that it is easy to attach and detach the plurality of resin rods to / from the gripping means.

  According to the resin rod tensioning apparatus according to the present invention, the interval between the output portion of the driving unit and the gripping unit is detected by the detection unit, and the quality of the resin rod is determined in light of the length that the resin rod extends due to the tension. be able to. For example, as the weight average molecular weight of the resin rod is smaller, the length that the resin rod extends tends to increase. Therefore, the length that the resin rod having the quality as a product is extended by tension is measured in advance. The length of the resin rod actually extended when the driving means operates the output unit as described above may be compared.

  Furthermore, according to the resin rod tensioning apparatus according to the present invention, the lifting means can lift and lower the pair of gripping means, and the storage tank for storing the immersion liquid is disposed below the pair of gripping means. The resin rod can be submerged in the immersion liquid in the storage tank by gripping both ends of the resin rod immediately after being molded with the pair of gripping means and the lifting means descending the pair of gripping means. Thereby, the temperature of the resin rod can be kept constant in the immersion liquid, and the heat fixation or relaxation of the resin rod can be advanced. Subsequently, when the lifting / lowering means raises the pair of gripping means, the pair of gripping means can release both ends of the resin rod that has been heat-fixed or relaxed when the resin rod is lifted from the storage tank.

  According to the heat fixing method of the present invention, a traction force is applied to at least one of both ends of the resin rod via the elastic member so as to relatively separate the both ends in the longitudinal direction of the resin rod, and tension is applied to the resin rod. Can be generated. Further, the temperature of the resin rod can be kept constant by immersing the resin rod in the immersion liquid as described above or placing the resin rod in a gas that conducts heat to the resin rod. The effect of this is as described above.

The side view which fractured | ruptured the resin rod tension | pulling apparatus which concerns on embodiment of this invention. The front view which fractured | ruptured the resin rod tension | pulling apparatus which concerns on embodiment of this invention. AA sectional view taken on the line AA of FIG. The side view which fractured | ruptured the principal part of the resin rod tension | pulling apparatus which concerns on embodiment of this invention. The side view which shows the example of attachment of the detection means applied to the resin rod tension | pulling apparatus which concerns on embodiment of this invention. The side view explaining operation | movement of the principal part of the resin rod tension | pulling apparatus which concerns on embodiment of this invention. The side view which fractured | ruptured the principal part of the resin rod tension | pulling apparatus which concerns on other embodiment of this invention.

  As shown in FIGS. 1 to 3, the resin rod tensioning apparatus 1 includes a pair of gripping means 7 and 9 that detachably grips both ends 5 of the biodegradable resin rod 3 in a posture extending in the horizontal direction, and a pair of Support means 11 that supports the gripping means 7 and 9 so as to move relative to or away from each other, drive means 15 that operates the output unit 13 in the direction in which the pair of gripping means 7 and 9 moves, and drive means The elastic member 17 which connects 15 output parts 13 to the holding means 7, and the below-mentioned variable spacer are provided.

  Since the drive source and guide means described below are self-evident elements, detailed description thereof will be omitted. For example, a feed screw mechanism in which a ball nut is screwed onto a screw shaft that is rotated by a motor may be used as a drive source, and the ball nut may be used as the output unit. Alternatively, an air cylinder having a piston rod as an output unit or a hydraulic cylinder may be used as a drive source. The guide means may be one in which a slider is engaged with a guide rail extending in the direction in which the drive source operates.

  The biodegradable resin rod 3 is mainly composed of polylactic acid, and the flanges at both end portions 5 are already crystallized portions. The support means 11 supports the horizontal members 21 and 23 by the four legs 19, attaches the movable frame 25 to the horizontal member 23 movably in the width direction via the guide means 27, and moves the lifting frame 29. It is attached to the frame 25 through a guide means 31 so as to be movable up and down. Here, the width direction is a horizontal direction orthogonal to the longitudinal direction of the biodegradable resin rod 3. The drive source 33 moves the elevating frame 29 together with the movable frame 25 in the width direction of the support means 11.

  The gripping means 7 is connected to the plurality of holding members 37 fixed to the lower ends of the plurality of support bodies 35, the plurality of sandwiching members 39 disposed above the plurality of receiving members 37, and the holding member 37. And an opening / closing means 41 for moving the sandwiching member 39 up and down. The gripping means 9 is configured in the same manner as the gripping means 7, and the gripping means 7, 9 are opposed to each other. The sandwiching member 39 is inserted between a pair of guide blocks 43 fixed to the support 35 so as to be movable up and down. The opening / closing means 41 is a drive source attached to the support 35, and its output portion 45 is joined to the sandwiching member 39. Reference numeral 47 indicates an opening through which the biodegradable resin rod 3 is inserted into the support 35.

  Each support 35 of the gripping means 7 includes a suspension rod 49, a suspension plate 53 formed with a plurality of slits 51 spaced in the width direction, and a guide means in which a guide rail 55 is fixed to the suspension plate 53. 57 and a moving member 61 that passes through the slit 51 of the suspension plate 53 and is joined to the slider 59 of the guide means 57, and is attached to the lifting frame 29. The guide means 57 guides the support 35 so as to be movable in the longitudinal direction of the biodegradable resin rod 3 with respect to the movable frame 25. Each moving member 61 has a contact plate 63 attached thereto.

  As shown in FIGS. 3 and 4, the drive means 15 is a drive source attached to the lower surface of the elevating frame 29, and advances and retracts the output portion 13 in the longitudinal direction of the biodegradable resin rod 3. Hanging members 65 and 67 are connected to the output unit 13, and a variable spacer 69 is attached to the hanging member 65. The variable spacer 69 is a drive source in which the output unit 71 protrudes from the cylinder 70 fixed to the hanging member 65. The drooping member 67 is joined to the slider 74 engaged with the guide rail 55.

  The drooping members 65 and 67 can advance and retreat in the longitudinal direction of the biodegradable resin rod 3 together with the slider 73. As the elastic member 17, a tension coil spring spanned between the support 35 of the gripping means 7 and the hanging member 67 may be applied. Although one elastic member 17 appears in the figure, two or more elastic members 17 may be provided.

  Further, the resin rod tensioning apparatus 1 includes a lifting / lowering means 75 for raising and lowering the pair of gripping means 7 and 9, and a storage tank 78 for storing an immersion liquid 77 such as glycerin disposed below the pair of gripping means 7 and 9. , 79, 80 and detection means 88. As shown in FIG. 1, the elevating means 75 is a drive source attached to the movable frame 25, and connects the output unit 81 to the elevating frame 29. As shown in FIG. 2, the storage tanks 78, 79, 80 are arranged in parallel with each other in the width direction of the support means 11 and are equipped with heaters for heating the respective immersion liquids.

  In FIG. 5, a part of the elastic member 17 is omitted to show the detection means 88. The detecting means 88 fixes the ultrasonic sensor 84 to the hanging member 67 of the driving means 15 via the stay 82, and the detected member 86 facing the head of the ultrasonic sensor 84 is attached to the guide block 43 of the gripping means 7. It is fixed. The ultrasonic sensor 84 may be any sensor that can detect the distance from the head to the detected member 86. The detected member 86 is a bent steel plate. Instead of the ultrasonic sensor 84, a photoelectric sensor may be applied to the detection means 88.

  Next, a heat setting method of the biodegradable resin rod 3 using the resin rod tensioning apparatus 1 will be described. A biodegradable resin rod 3 having a diameter of about 3.8 to 8.5 [mm] is selected. The temperature of the immersion liquid 77 should just be more than the crystallization peak temperature of polylactic acid (for example, 120 degreeC). The spring constant of the elastic member 17 is assumed to be 0.093 [N / mm]. The resin rod tensioning device 1 operates the output unit 13 of the driving unit 15 in the direction of the arrow F, and is connected to the output unit 13 so that the interval between the pair of gripping units 7 and 9 reaches an initial dimension described later. The gripping means 7 is moved together with the hanging members 65 and 67. The initial dimension may be a dimension that exceeds the total length of the biodegradable resin rod 3 and is not particularly limited.

  The dimension in which the output portion 71 of the variable spacer 69 protrudes from the hanging member 65 is defined. That is, as shown in FIG. 6, the variable spacer 69 operates the output unit 71 in the direction opposite to the arrow F, and abuts the output unit 71 against all the contact plates 63 shown in FIG. 3. When the variable spacer 69 further moves the output portion 71 in the direction opposite to the arrow F, and the distance between the hanging member 67 and the support 35 of the gripping means 7 becomes wider than the free length of the elastic member 17, the variable spacer 69 is The output unit 71 is stopped. At this point, the elastic member 17 is moderately tensioned.

  The driving unit 15 operates the output unit 13 in the direction opposite to the arrow F, and moves the pair of gripping units 7 and 9 in directions that are relatively close to each other. As a result, the gripping means 7 is moved to the position indicated by the phantom line in FIG. 4, and when the distance between the pair of gripping means 7, 9 is slightly smaller than the total length of the biodegradable resin rod 3, the driving is performed. The means 15 stops the output unit 13. Alternatively, when the elastic member 17 is tensioned by the variable spacer 69 operating the output unit 71 in the direction opposite to the arrow F as described above, the interval between the pair of gripping means 7 and 9 is biodegradable. The initial dimension may be set in advance so as to be slightly narrower than the entire length of the resin rod 3.

  In a state where the opening / closing means 41 raises the sandwiching member 39 together with the output part 45 from the holding member 37, the plurality of holding members 37 receive the both ends 5 of the plurality of biodegradable resin rods 3. As described above, when the output portions 71 are abutted against all the contact plates 63, all the support bodies 35 shown in FIG. 3 are in the horizontal direction perpendicular to the longitudinal direction of the biodegradable resin rod 3. Align straight along. For this reason, there is an advantage that it is not necessary to adjust the arrangement of the individual holding members 37 each time the both end portions 5 of the biodegradable resin rod 3 are received by the holding members 37.

  The opening / closing means 41 lowers the sandwiching member 39 together with the output unit 45, and sandwiches both end portions 5 of the plurality of biodegradable resin rods 3 between the holding member 37 and the sandwiching member 39. As a result, when both end portions 5 of all the biodegradable resin rods 3 are gripped by the gripping means 7, 9, the variable spacer 69 operates the output portion 71 in the direction of the arrow F, and the contact plate of the moving member 61. Retreat from 63. In this process, the output portion 71 is detached from the contact plate 63, but the biodegradable resin rod 3 held by the holding means 7 and 9 receives the elastic force of the elastic member 17. The tension of the elastic member 17 is maintained between

  In a state where the opening / closing means 41 raises the sandwiching member 39 together with the output part 45 from the holding member 37, the plurality of holding members 37 receive the both ends 5 of the plurality of biodegradable resin rods 3. As described above, when the output portions 71 are abutted against all the contact plates 63, all the support bodies 35 shown in FIG. 3 are in the horizontal direction perpendicular to the longitudinal direction of the biodegradable resin rod 3. Align straight along. For this reason, there is an advantage that it is not necessary to adjust the arrangement of the individual holding members 37 each time the both end portions 5 of the biodegradable resin rod 3 are received by the holding members 37.

  The opening / closing means 41 lowers the sandwiching member 39 together with the output unit 45, and sandwiches both end portions 5 of the plurality of biodegradable resin rods 3 between the holding member 37 and the sandwiching member 39. As a result, when both end portions 5 of all the biodegradable resin rods 3 are gripped by the gripping means 7, 9, the variable spacer 69 operates the output portion 71 in the direction of the arrow F, and the contact plate of the moving member 61. Retreat from 63. In this process, the output portion 71 is detached from the contact plate 63, but the biodegradable resin rod 3 held by the holding means 7 and 9 receives the elastic force of the elastic member 17. The tension of the elastic member 17 is maintained between

Subsequently, the driving unit 15 operates the output unit 13 in the direction of the arrow F, and moves the pair of gripping units 7 and 9 in a direction in which they are relatively separated from each other. The lifting / lowering means 75 lowers the pair of gripping means 7 and 9 and sinks the biodegradable resin rod 3 in the immersion liquid 77 of the storage tank 79. In the state where the driving unit 15 operates the output unit 13 in the direction of the arrow F as described above, the output unit 13 of the driving unit 15 continues to pull the gripping unit 7 in the direction of the arrow F via the elastic member 17. As a result, tension is generated in the plurality of biodegradable resin rods 3 that are respectively held at the both ends 5 by the pair of gripping means 7 and 9, so that the plurality of biodegradable resin rods 3 are placed in the immersion liquid 77. Can be fixed by heat. In this case, as the tension generated in the individual biodegradable resin rod 3 is about ^{_{0.3~1.5 [kg f / mm 2]}} , it is preferable to set the elastic force of the elastic member 17.

  When the heat fixing of the biodegradable resin rod 3 is completed, the lifting / lowering means 75 raises the pair of gripping means 7 and 9, thereby lifting the biodegradable resin rod 3 from the storage tank 79. The driving unit 15 operates the output unit 13 in the direction opposite to the arrow F, and operates the pair of gripping units 7 and 9 in a direction approaching relatively. This breaks the tension of the biodegradable resin. Finally, when the opening / closing means 41 raises the output portion 45, the biodegradable resin rod 3 can be released from the gripping means 7, 9.

  The variable spacer of the resin rod tensioning device 1 may be omitted. The difference between the heat setting method in this case and the first embodiment will be described next. The resin rod tensioning device 1 moves the gripping means 7 so that the distance between the pair of gripping means 7 and 9 facing each other is slightly narrower than the total length of the biodegradable resin rod 3. The holding member 37 receives both end portions 5 of the plurality of biodegradable resin rods 3, and the gripping means 7 and 9 grip all the end portions 5 of the biodegradable resin rods 3.

  Subsequently, the driving unit 15 operates the output unit 13 in the direction of the arrow F. Thereby, the space | interval of the support body 35 of the holding means 7 and the drooping member 67 is expanded, and the elastic member 17 is tensioned between both. The lifting / lowering means 75 lowers the pair of gripping means 7 and 9 and sinks the biodegradable resin rod 3 in the immersion liquid 77 of the storage tank 79. Since tension based on the elastic force of the elastic member 17 is generated in the biodegradable resin rod 3 in a state where the elastic member 17 is tensioned as described above, the biodegradable resin rod 3 is thermally fixed in the immersion liquid 77. can do.

  As shown in FIG. 7, the holding member 30 extending downward may be fixed to the lifting frame 29 of the support means 11, and the driving means 15 and the elastic member 17 may be attached to the holding member 30. The difference between the heat setting method in this case and the second embodiment will be described next.

  The driving unit 15 operates the output unit 13 in the direction opposite to the arrow F. As a result, the output unit 13 comes into contact with the contact plate 63 of the moving member 61 and the interval between the support 35 of the gripping means 7 and the holding member 30 is widened. Then, when the gripping means 7 moves to the position represented by the phantom line in FIG. 7, the driving means 15 stops the output unit 13. At this point, the elastic member 17 is moderately tensioned between the support 35 of the gripping means 7 and the holding member 30, and the distance between the pair of gripping means 7, 9 is less than the total length of the biodegradable resin rod 3. Is a little narrower.

  The holding member 37 receives both end portions 5 of the plurality of biodegradable resin rods 3, and the gripping means 7 and 9 grip all the end portions 5 of the biodegradable resin rods 3. Subsequently, the driving unit 15 operates the output unit 13 in the direction of the arrow F. Thereby, although the output part 13 detaches | leaves from the contact plate 63 of the moving member 61, the tension | tensile_strength of the elastic member 17 is maintained between the support body 35 and the holding member 30 of the holding means 7. FIG. In this state, a traction force in the direction of arrow F is applied to the biodegradable resin rod 3 via the elastic member 17, so that the tension necessary to heat-fix the biodegradable resin rod 3 is applied to the biodegradable resin rod 3. appear.

  In the embodiment described above, the entire length of the biodegradable resin rod 3 expands and contracts as the heat fixation of the biodegradable resin rod 3 progresses. However, the elastic member 17 corresponds to the longitudinal direction of the biodegradable resin rod 3. Therefore, the biodegradable resin rod 3 is not warped. In this manner, the linear biodegradable resin rod 3 can be attached to a main shaft such as a lathe, and an appropriate screw can be ground on the biodegradable resin rod 3.

  Since the elastic member 17 can be expanded and contracted, an unnecessary increase or decrease in the tension of the biodegradable resin rod 3 can be suppressed, so that the internal stress remaining in the biodegradable resin rod 3 can be removed or the crystal structure thereof can be adjusted well. be able to. For this reason, even if the biodegradable resin rod 3 is heated at the stage of sterilization, the dimensions or the shape of the screw will not be distorted, and the biodegradable resin rod 3 can satisfy the quality as a product. it can.

  Further, since sensors for measuring the tension of the biodegradable resin rod 3 and a computer for controlling the operation of the driving means 15 are not required, the resin rod tensioning apparatus 1 has a simple structure and a manufacturing cost. Inexpensive. In addition, since the gripping means 7 operates as described above in a state where both end portions 5 of the plurality of biodegradable resin rods 3 are sandwiched between the plurality of holding members 37 and the plurality of sandwiching members 39, Even if the total lengths of the plurality of biodegradable resin rods 3 are different from each other due to errors in manufacturing, etc., tension equal to all the biodegradable resin rods 3 can be generated.

  Further, according to the resin rod tensioning apparatus 1, before the driving unit 15 operates the output unit 13 in the direction of the arrow F, the driving unit 15 is tensioned as described above, whereby the driving unit 15 As soon as the operation is started, tension can be generated in the biodegradable resin rod 3 immediately. In consideration of the contraction rate of the biodegradable resin rod 3, when the elastic force of the elastic member 17 needs to be set as desired, the drooping member 67 is adjusted by adjusting the stroke by which the variable spacer 69 operates the output unit 71. The interval between the gripping means 7 and the support 35 may be increased or decreased.

  When the above-described tension is applied to the biodegradable resin rod 3, the extension length of the biodegradable resin rod 3 tends to increase as the weight average molecular weight decreases. Then, the length which expand | extends when the biodegradable resin rod which has the quality as a product is heat-set is measured previously. If this measured value is compared with the amount of change in the distance between the driving means 15 and the gripping means 7 detected by the detecting means 88, in other words, the length in which the biodegradable resin rod 3 is actually elongated, the biodegradable resin The quality of the bar 3 can be determined.

  It should be noted that the present invention can be carried out in a mode in which various improvements, modifications, or variations are added based on the knowledge of those skilled in the art without departing from the spirit of the present invention. It is not essential to heat-fix the biodegradable resin rod 3 in the immersion liquid 77, and the biodegradable resin rod 3 may be heat-set in a gas heated to a predetermined temperature.

  Although the gripping means 7 and 9 described the example which raises / lowers the clamping member 39 with respect to the holding member 37, when the clamping member 39 moves in a horizontal direction, the holding member 37 and the clamping member 39 are moved. You may make it open and close. Further, the posture of the biodegradable resin rod 3 is not limited, and the pair of gripping means 7 and 9 are opposed to each other in the vertical direction to grip both ends 5 of the biodegradable resin rod 3 from which they stand. May be. The gripping means 7 may be fixed to the movable frame 25, the gripping means 9 may be movably attached to the movable frame 25, and the driving means 15 may move the gripping means 9 in the longitudinal direction of the biodegradable resin rod 3.

  Further, the biodegradable resin rod 3 may be stretched or relaxed by using the tension applied to the biodegradable resin rod 3 by the resin rod tensioning device 1. In this case, the immersion liquid stored in the storage tanks 78 and 80 can be individually set so as to have a temperature suitable for stretching or relaxation. If the drive source 33 stops the elevating frame 29 just above the storage tank 78 and the elevating means 75 lowers the pair of gripping means 7 and 9, the biodegradable resin rod 3 is submerged in the immersion liquid in the storage tank 78. I can do it. Alternatively, if the drive source 33 stops the lifting frame 29 just above the storage tank 80 and the lifting means 75 lowers the pair of gripping means 7 and 9, the biodegradable resin rod 3 is immersed in the storage tank 80. Can be submerged.

  The use of the resin rod that is stretched, heat-set, or relaxed by the resin rod tensioning apparatus according to the present invention is not limited for medical use. Moreover, this invention is applicable not only to biodegradable resin but to the extending | stretching, heat setting, or relaxation process of all materials.

  DESCRIPTION OF SYMBOLS 1 ... Resin rod tension | pulling apparatus, 3 ... Biodegradable resin rod, 5 ... Both ends, 7, 9 ... Holding means, 11 ... Support means, 13, 45, 71, 81. ..Output part, 15 ... drive means, 17 ... elastic member, 19 ... leg part, 21,23 ... horizontal material, 25 ... movable frame, 27, 31, 57 .. Guide means 29 ... Elevating frame, 30 ... Holding member, 33 ... Driving source, 35 ... Support, 37 ... Holding member, 39 ... Clamping member, 41. ..Opening and closing means, 43 ... guide block, 47 ... opening, 49 ... suspending rod, 51 ... slit, 53 ... suspending plate, 55 ... guide rail, 59, 73, 74 ... slider, 61 ... moving member, 63 ... contact plate, 65, 67 ... hanging member, 69 ... variable spacer, 70 ... cylinder, 75 ... lift Means: 77 ... immersion liquid, 78, 79, 80 ... storage tank, 82 ... stay, 84 ... proximity sensor, 86 ... detected member 88 ... detection means.

Claims (7)

  A pair of gripping means for detachably gripping both ends of the resin rod in the longitudinal direction, a support means for supporting the pair of gripping means movably in the longitudinal direction, and a driving means for operating the output unit in the longitudinal direction And an elastic member that connects at least one of the pair of gripping means to the output portion of the driving means. A pair of gripping means for detachably gripping both ends of the resin rod, a support means for movably supporting the pair of gripping means so as to approach or separate from each other, and an output in the direction of movement of the gripping means A driving means for operating the unit, a variable spacer for defining an interval between the output part of the driving means and the gripping means to be an extension length of the elastic member, and an output part of the driving means for the pair of gripping means. An elastic member connecting at least one,
In the process in which the output portion of the driving means operates in a direction to relatively separate the pair of gripping means, both ends are gripped by the pair of gripping means by pulling the gripping means via the elastic member. A resin rod tensioning device for generating tension on a resin rod. The pair of gripping means includes a plurality of holding members for receiving a plurality of resin rods, a plurality of clamping members disposed above the plurality of receiving members, and the clamping members with respect to the receiving members. Opening and closing means for raising and lowering,
The opening / closing means lowers the plurality of sandwiching members to sandwich a resin rod between the holding member and the sandwiching member, and raises the plurality of sandwiching members to raise the resin rod. The resin rod tensioning device according to claim 1, wherein the resin rod tensioning device is released.   4. The detection unit according to claim 1, further comprising a detection unit configured to detect an interval between the output unit of the drive unit and a gripping unit coupled to the output unit by the elastic member. 5. Resin rod tension device. Elevating means for raising and lowering the pair of gripping means; and a storage tank for storing immersion liquid that is disposed below the pair of gripping means and conducts heat to the resin rod,
The pair of gripping means grips both ends of the resin rod, and the lifting means lowers the pair of gripping means to a height at which the resin rod sinks into the immersion liquid in the storage tank. The resin rod tensioning device according to any one of 1 to 4.   In a heat fixing method in which the resin rod is kept at a constant temperature in a state where tension is generated in the resin rod by a pulling force in a direction in which the both ends in the longitudinal direction of the resin rod are relatively separated from each other, A heat fixing method, wherein a traction force is applied to at least one of the elastic members through expansion and contraction in the longitudinal direction.   The heat setting method according to claim 6, wherein the temperature of the resin rod is kept constant in a gas or liquid that conducts heat to the resin rod.

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