JP5125714B2 - Sheet-like material drawing machine and sheet-like material drawing method - Google Patents

Description

  The present invention relates to a stretching machine for stretching a sheet-like material such as a thermoplastic resin film, and a stretching method.

  Conventionally, as a method for producing a sheet-like material used for a retardation plate or a polarizing plate having an orientation axis inclined with respect to the periphery, a sheet-like material having an orientation axis perpendicular to (or parallel to) the side in the width direction. Accordingly, the periphery is manufactured by punching the periphery so that the orientation axis becomes a predetermined inclination angle. However, there is a problem that a portion that cannot be used in the vicinity of the end portion of the sheet-like material is generated by punching, and the yield is deteriorated particularly in a large-size retardation plate.

  As a known example for solving this problem, Japanese Patent Application Laid-Open No. 2-113920 (Patent Document 1) discloses that the longitudinal travel distance of the chuck in the predetermined travel section differs between the left and right end portions in the width direction of the film. A manufacturing method is described in which a film is stretched in a direction oblique to the length direction (longitudinal direction) of the film by gripping and traveling between two rows of chucks traveling on the arranged tenter rail.

  In addition, JP 2000-9912 A (Patent Document 2) discloses that a plastic film is stretched uniaxially in the horizontal or vertical direction, while the left and right sides of the stretching direction are different from each other in the vertical or horizontal direction at different speeds. A production method is described in which the orientation axis is tilted with respect to the uniaxial stretching direction by stretching.

Japanese Patent Laid-Open No. 2-113920 Japanese Patent Laid-Open No. 2000-9912

  However, the manufacturing method of Patent Document 1 has a problem that wrinkles are generated when the tilt angle is increased, and further, there is a drawback that the tilt angle is fixed and the tilt angle is fixed and there is no degree of freedom. According to the method of Patent Document 2, there is an advantage in that the inclination angle has a degree of freedom and is less exclusive. However, even in this method, wrinkles are generated when the conveyance speed difference is increased, and a desired inclination angle is obtained. Is difficult. And as mentioned above, when wrinkles occur in the film, it cannot be used as a product and the yield decreases.

  In general, since the film is gripped at both ends in the width direction, the longitudinal shrinkage stress accompanying stretching in the width direction is restrained by the gripping means. Tends to move and curve in the vertical direction. This is called the Boeing phenomenon and causes non-uniform physical properties in the width direction of the film, especially optical characteristics such as orientation angle distribution, mechanical characteristics, humidity expansion coefficient, thermal expansion coefficient, and thermal contraction ratio. . In particular, there is a concern about the bowing phenomenon in unreasonable stretching or oblique stretching.

  An object of the present invention is to provide a sheet-like material stretching machine and a sheet-like material stretching method that improve the yield by preventing wrinkles and bowing as a retardation plate or a film for a polarizing plate. is there.

  In order to achieve the above object, the present invention provides a plurality of linked links having gripping devices for gripping both left and right ends of a thermoplastic sheet material along a closed guide rail on a substantially horizontal plane. Each of the endless link devices includes a pair of endless link devices that are guided and stretched while being conveyed from the inlet side to the outlet side of the guide rail and then traveled back to the inlet side. A preheating region for preheating while conveying the sheet-like material disposed on the inlet side while maintaining a substantially constant width, while conveying the sheet-like material arranged on the downstream side of the preheating region, A stretching region in which a diverging portion is provided on the guide rail for stretching the sheet-like material in the width direction and the longitudinal direction by gradually increasing the gripping pitch of the gripping device, and the stretching disposed on the downstream side of the stretching region. Said sea It has a heat fixing region for heat fixing while transporting while keeping the width of the article substantially constant, and at least a plurality of units of the extended region and the heat fixing region connected to each other are arranged. .

  Further, the longitudinal magnification of the gripping pitch of the link device located in the extending region is made different between the left and right ends in the width direction of the sheet-like material. In addition, at least a plurality of units of the preheating region, the stretching region, and the heat fixing region that are connected to each other are arranged. Further, a buffer area is provided between the plurality of units.

  In addition, the opening angle of the guide rails arranged in the shape of the end of the extending region is made different from left to right. Further, the enlargement magnification in the longitudinal direction of the gripping pitch of the link device located in the extension region is set higher in the unit located downstream than the unit located upstream.

  In the present invention, a plurality of linked links having gripping devices for gripping the widthwise left and right ends of the thermoplastic sheet-like material are guided along a closed guide rail on a substantially horizontal plane, The sheet-like article is provided with a pair of endless link devices that travel while being conveyed from the inlet side to the outlet side of the guide rail and then returned to the inlet side and travel. The width of the gripper is preheated while being transported, and the gripping pitch of the gripping device is gradually increased while transporting the sheet-like material in the first stretching region arranged on the downstream side of the preheated region. The sheet material is stretched in the width direction and the longitudinal direction, and is conveyed while maintaining the width of the sheet material stretched in the first heat setting region disposed on the downstream side of the first stretching region. And fixed on the downstream side of the first heat setting area. In the second stretched region, the sheet-like material is conveyed, while the gripping pitch of the gripping device is gradually increased to stretch the sheet-like material in the width direction and the longitudinal direction, and the wake of the second stretched region. In the second heat setting region arranged on the side, the stretched sheet-like material is heat-set while being conveyed while being kept substantially constant.

  Further, in at least one of the first stretched region and the second stretched region, the sheet-like material is made different in the longitudinal magnification of the gripping pitch of the link device at the left and right ends in the width direction of the sheet. It is characterized by stretching the shape.

  ADVANTAGE OF THE INVENTION According to this invention, the wrinkle and bowing phenomenon of a sheet-like thing applied to a phase difference plate or a polarizing plate can be prevented, the yield of a product can be improved, and productivity can be improved.

  Hereinafter, examples of the present invention will be described in detail with reference to the drawings. First, a simultaneous biaxial stretching machine which is a basic form of the present invention will be described with reference to FIGS. FIG. 7 is a plan view of the simultaneous biaxial stretching machine, and FIG. 8 is a diagram schematically showing the outline of the configuration of the link device of the stretching machine shown in FIG.

  A configuration of a sheet-like material drawing machine 1 according to an embodiment of the present invention and a link device used therefor will be described. A sheet-like material drawing machine 1 shown in FIG. 7 includes a conveyance space 2 in which a sheet-like material 20 made of a thermoplastic resin or the like that extends in the center is conveyed, and a link guide rail that forms a closed path. 3 endless link devices 4, 5 that are driven on and circulate while gripping and transporting and releasing each of the left and right ends in the width direction of the sheet-like material are paired on both sides of the conveyance direction of the sheet-like material in the conveyance space 2. Has been placed.

  In these endless link devices 4 and 5, the sprockets 6 and 7 disposed on the inlet side of the sheet-like material in the conveyance space 2 and the sprocket 8 disposed on the outlet side are connected to a driving device such as a motor (not shown). The link device 200 that is rotationally driven and meshed with these sprockets 6, 7, 8 slides on the link guide rail 3 and moves.

  That is, as shown in FIG. 8 (a), the endless link device 4 or 5 having a plurality of (multiple) gripping devices 202 for gripping the end of the sheet-like material 20 on both sides of the sheet-like material (the link in the figure). A part and one endless link are omitted), and a plurality of (multiple) equal-length links 201 formed in a fold-like shape are connected to each other and include a link device 200 configured to be closed in an annular shape. The link device 200 is driven by a sheet-like material entrance-side sprocket 6 or 7 and travels on the link guide rail 3 to open / close means (not shown) such as an open / close guide provided at the entrance of the conveyance space 2. As a result, the gripping device 202 is opened and closed to grip the sheet-like material 20, and the sheet-like material is heated to a temperature necessary for stretching in the preheating region 9, and travels on the conveyance side rail of the link guide rail 3. At this time, the sheet-like article 20 is heated while being conveyed while keeping the width thereof substantially constant.

  Next, the link device 200 is guided by the link guide rails 3 arranged in a divergent shape in the traveling direction in the extending region 10 arranged on the downstream side of the preheating region 9, and the grip pitch between the grip devices 202. Is gradually expanded from P1 to P2, whereby the sheet-like material 20 is simultaneously stretched in two directions. The stretching in the lateral direction is performed by traveling on the guide rail 3 having a widening end.

  In this region 9, the left and right guide rails 3 are respectively placed on a plurality of link beds 3 a and 3 b connected by joints, and the link beds 3 a and 3 b are moved in the width direction by the motor unit 3 c, It opens and closes (wide and narrow). By installing the link head so as to gradually open along the traveling direction of the sheet-like material, the guide rail 3 on the link head is disposed so as to spread outwardly in the traveling direction. Further, the link beds 3a and 3b can be moved separately by the motor unit 3c. In this case, the opening angle of the guide rail 3 at the end can be varied on the left and right in the width direction.

  Thereafter, in the heat setting region 11 arranged on the downstream side of the stretching region 10, the sheet-like material 20 is heat fixed at a predetermined temperature while being conveyed while being kept substantially constant, and then an opening / closing guide provided at the outlet The gripping device 202 is opened and removed from the sheet by an opening / closing means (not shown) such as the like, and the removed sheet is advanced as it is. The link device 200 is configured to be driven by the sprocket 8 on the outlet side, travel on the return side rail of the link guide rail 3 and return to the inlet side sprocket 6.

  The link guide rail 3 is composed of a pair of rails 206 on the inner and outer peripheral sides, each of which is formed of a beam-like member having a substantially rectangular cross section arranged so as to be convex as shown in FIG. , 205. A joint on which a gripping device 202 for gripping a sheet-like object is connected to a rail 205 on the outer peripheral side closer to the sheet-like object 20 in the conveyance-side rail in which the equal-length link 201 travels while gripping the sheet-like object. A link shaft 207 is disposed. A joint link shaft 208 without the gripping device 202 is disposed on the inner rail 206.

  The link shaft 207 and the link shaft 208 are connected by link plates 209 and 210. Bearing holders 211 and 212 having bearing rollers 211a and 212a, which are first rolling bearings, are connected to the lowermost ends of the link shafts 207 and 208, and both sides of the bearing holders 211 and 212, that is, the bearing rollers 211a and 212a. A pair of radial bearings 213 [213a, 213b] and 214 [214a, 214b], which are a pair of second rolling bearings, are attached to the outer periphery. The flanged radial bearings 213 and 214 roll on both side surfaces of the rails 205 and 206 that restrict the movement of the isometric link 201, and the upper surface of the rails 205 and 206 and the flanges of the flanged radial bearings 213 and 214 contact each other. The isometric link 201 is arranged so as to hold its own weight.

  FIG. 8C shows a rail 205 installed on a plurality of link beds 3a and 3b (FIG. 7 is 6 sections and FIG. 8 is 2 sections) connected by the joints described above, which are located in the extension region 10. 206 and the isometric link 201 are schematically illustrated. In the closed state and the open state of the link, the crossing angles (θ) of the link plate 209 and the guide rail are θ1 and θ2, respectively, which are different angles. . Even at this time, the radial bearings 213 [213a, 213b] and 214 [214a and 214b] supported by the bearing holders 211 and 212 are operated (rotated) by the bearing rollers 211a and 212a with respect to the link shafts 207 and 208. It always changes (rotates) so as to be positioned substantially perpendicular to both side surfaces of the rails 205 and 206.

  Accordingly, since the pair of radial bearings with flanges can always be at a constant angle with respect to the rail, the link device does not depend on the intersection angle (θ) of the link plates 209 and 210 and the rails 205 and 206 or the rail width. It becomes possible to drive 200 stably.

  FIG. 8C shows a state in which the amount of stretching in the MD direction (longitudinal direction, traveling direction) (enlargement magnification, magnification in the longitudinal direction of the sheet-like material) is larger than 1.0. That is, compared to the left side in the figure, the rail 206 and the rail 205 are arranged so as to approach gradually on the right side, and the link device 200 travels along these, thereby opening the link of each equal-length link 201. The angle gradually increases, the gap between the adjacent equal-length links 201 and the gap between the gripping devices 202 (not shown) gradually spread in the MD direction, and the sheet is stretched in the traveling direction. Furthermore, by using spring steel to connect the guide rails not shown in the figure and the guide rails in the figure, a plurality of link beds can be connected by joints, and the guide rails can be arranged endlessly.

  In this embodiment, the method of extending the sheet-like material in the traveling direction is shown. However, by making the distance between the illustrated rails 206 and 205 the same on both the left and right sides, θ1 and θ2 are made substantially the same. It is also possible not to change the amount of extension in the MD direction on the left and right sides of the figure, and conversely to FIG. 8C, the distance between the rails 206 and 205 is widened from the left side to the right side to open the link of the link device. By reducing the angle on the right side of the figure, the sheet can be contracted with respect to the film traveling direction. In addition, by combining with a stepless variable technology (configuration in which the link guide rail 3 is arranged in a divergent shape) of the amount of extension (enlargement magnification) in the TD direction (lateral direction, width direction), the extension in the TD direction and MD direction The amount can be set freely.

  The distance between the guide rails 205 and 206 is adjusted by changing the distance between the two link beds 3a and 3a (see FIG. 8) on which the rails are mounted by a motor unit 3c. The amount can be set differently on both sides in the width direction. Therefore, when narrowing the distance between the two rails, if the distance between the rails on one side in the width direction is changed to be small and the distance between the rails on the other side is changed to be greatly changed, the magnification ratio of stretching on both sides in the width direction can be increased. Differently, the sheet can be stretched obliquely.

  As described above, the conveyance space 2 between the endless link devices 4 and 5 is roughly divided into three regions, and is divided into a preheating region 9, an extending region 10, and a heat fixing region 11 from the inlet side toward the outlet side. It is done. Here, the connected preheating region 9, the extending region 10 and the heat setting region 11 are one unit, or the connecting extending region 10 and the heat fixing region 11 are one unit. Each of the areas is composed of one or more spaces.

  As shown in FIGS. 7 and 8, a plurality of nozzles 12 (not shown) are provided below the end of the link device 200 that grips the sheet-like material in the conveyance space 2 in which the sheet-like material in each region is conveyed. ) Is arranged. Each nozzle 12 is connected to a duct 13 extending laterally on the sheet end side, and heated air introduced from the duct 13 is introduced into the nozzle 12. The high-temperature air introduced into the space in the nozzle 12 is blown out toward the lower surface of the sheet-like object 20 passing above the blow-out opening that is opened upward above the nozzle 12.

  When such a high-temperature air supply is received from the plurality of nozzles 12 and the sheet-like material 20 is heated to a high temperature in the preheating region 9, the thermoplastic sheet-like material is easily deformed. Thus, the occurrence of damage or deformation bias during deformation in the rearward stretching region is suppressed. The preheating region 9 serves as an inlet through which the sheet-like material is introduced into the conveyance space 2, and the sheet-like material side end portion of the link device 200 guided and driven by the link guide rail 3 at the entrance. The gripping device 202 grips the end portion of the sheet-like material 20 and pulls the sheet-like material toward the exit side of the conveyance space 2 that is the direction of the circular operation of the link device 200 to start conveyance.

  In the extending region 10 adjacent to the wake side of the preheating region 9, the link guide rails 3 of the endless link devices 4 and 5 facing each other at both ends of the sheet-like material 20 are arranged in a divergent shape. The link device 200 guided in the step can extend (extend) the end portion of the sheet-like object 20 to be gripped in the direction of both ends (width direction, lateral direction). Also in the stretching region 10, air at a higher temperature than the plurality of nozzles 12 is supplied and blown to the lower surface of the sheet-like material, so that damage during stretching of the sheet-like material and unevenness of the stretching amount are suppressed.

  In this region 10, the guide rail 3 is placed on the link bed 3a (see FIG. 8) connected by the plurality of joints described above, and the angle of each link bed, the interval between the two guide rails, or As described above, these can be set individually.

  In the heat fixing region 11 adjacent to the rear of the extending region 10, the link guide rails 3 of the endless link devices 4 and 5 are arranged substantially in parallel with each other while maintaining the distance at the outlet of the extending region 10. The sheet-like object 20 gripped by is conveyed with a substantially constant width. At the same time, it is supplied with high-temperature air from a plurality of nozzles 12 arranged below this region, and is heated while maintaining the stretched state, and its shape and length are fixed. Stress is removed.

  Next, an example of oblique stretching using a simultaneous biaxial stretching machine will be described. FIG. 1 is a schematic view of an obliquely stretched state. The conveyance space 2 for conveying the sheet-like material 20 and the gripping position (marked with ● in the figure) of the gripping device 202 for the equal-length link 201 and the equal-length link 201 travel. FIG. 6 is a schematic diagram illustrating a tension direction (a tension direction due to stretching) in a balanced state of the equal-length links 201 positioned at both ends of the guide rail 3 and the sheet-like object indicated by a solid line 14. 201L indicates a grip position at the left end in the width direction of the sheet-like material, and 201R indicates a grip position at the right end in the width direction of the sheet-like material.

  A force acts on the sheet-like material in the preheating region 9 in a direction substantially perpendicular to the traveling direction by the opposed equal-length links 201. In the stretching region 10, the pitch of the grip position 201L at the left end of the equal-length link above the sheet-like object center line (one-dot chain line) is set to P1 <P3 <P4, and the equal-length link below the sheet-like object center line The pitch of the right end gripping position 201R is set to P1 <P2 <P4. Then, by setting the pitch between the two as P2 <P3, a tension like a solid line 14 having an inclination α with respect to the straight line in the width direction acts on the sheet-like object 20. That is, since the tension acting on the sheet-like material 20 is approximated to the orientation of the sheet-like material, it can be said that the sheet-like material 20 is in an orientation state having an inclination of about α. The direction of the tension acting on the sheet-like object 20 is determined by the inclination angle of the line after drawing (drawing) a line at equal intervals in a direction perpendicular to the center line of the sheet-like object (drawing). did.

  On the other hand, the inclination angle α is determined by the amount of deviation of the equal-length link 201 positioned above and below the sheet center line and the width W of the outlet side sheet material (actually generated by various sheet materials and stretching conditions). It is necessary to take into account the amount of shrinkage to be). Accordingly, if the ratio of the amount of deviation with respect to the width W is increased, oblique stretching with a large inclination angle is possible, but there is actually a limit to the inclination angle from the viewpoint of preventing the generation of wrinkles.

  FIG. 2 schematically shows an example of an oblique stretching experiment when the tilt angle is increased. Initially, in this experiment, it was considered that the tension acts on the sheet-like object 20 as indicated by the solid line 14 having the angle α shown in FIG. 1, but in reality, the isometric links so that the force is balanced by the broken line 15 from the middle of stretching. As a result, the tensile force acts on the sheet-like material 20 at the broken line 15 having an angle α ′. In addition, the generation of wrinkles similar to that described in the prior art was confirmed in the sheet-like material (occurred in the process in which the balance of force is shifted from the solid line 14 to the broken line 15).

  From this experiment, it was found that the inclination angle that can be obliquely stretched by one stretch is several tens of degrees or less. Then, when the film that was obliquely stretched once was stretched again under the same conditions, the tilt angle was about twice, and it was found that by repeating the small tilt angle, a sheet-like product having a large tilt angle could be produced without wrinkles. . In addition, it cannot be overemphasized that this angle changes with material properties and extending | stretching conditions of various sheet | seats.

  A specific configuration of this embodiment will be described with reference to FIG. In FIG. 3, the extension region 10 described above is moved by moving a plurality of link beds 3 a connected by joints arranged in this region 10, and the interval between the guide rails 3 is changed to three stages. It is characterized in that it is subdivided into a stretching region 100, a first heat setting region 110, and a second stretching region 101, and 11 is a second heat fixing region. In other words, when the extending region and the heat fixing region connected to each other are one unit, two units are arranged.

  In the stretching region 10, the pitch of the grip position 201L at the left end of the isometric link above the sheet-like object center line (one-dot chain line) is set to P1 <P3 <P4 <P6 <P7, and below the sheet-like object center line. The pitch of the grip position 201R at the right end of the isometric link is set to P1 <P2 <P4 <P5 <P7. And the pitch of the width direction both ends is set with the relationship of P2 <P3 and P5 <P6.

  This example shows an example in which two stretching operations are continuously achieved by one stretching machine. That is, oblique stretching with a relatively small inclination angle α1 as shown by the solid line 14 is performed in the first stretching region 100, and the internal tension acting on the sheet-like object 20 is relaxed in the first heat setting region 110. Next, in the second stretching region 101, a force acts on the isometric links at positions relatively close to the longitudinal direction, and the tension acting line on the sheet-like object 20 has a relatively small inclination angle α2, And stretched. Therefore, in the second stretched region 101, when the sheet-like material 20 obliquely stretched in the first stretched region 100 is obliquely stretched again, when viewed from the sheet-like material 20 in the preheating region 9, the solid line 14 and the alternate long and short dash line 16 are A sheet-like object having a large inclination angle (α1 + α2) of the combined broken line 15 is obtained.

  In the second stretching region 101, stretching is started from a state where the tension acting on the sheet-like material 20 is relaxed in the first heat setting region 110 in the preceding stage, and at the end of stretching, only a small tilt of the tilt angle α2 is used. Since it is not stretched, generation of wrinkles is prevented. Therefore, by stretching in small increments by this two-time stretching, oblique stretching without wrinkles can be achieved with a large inclination angle finally.

  Explaining the order of stretching in this embodiment, a plurality of linked links having gripping devices for gripping both left and right ends of the thermoplastic sheet-like material are guided along closed guide rails on a substantially horizontal plane. A preheating region disposed on the inlet side, which is provided with a pair of endless link devices that travel while being returned to the inlet side after the sheet-like material is stretched while being conveyed from the inlet side to the outlet side of the guide rail The gripping pitch of the gripping device is preheated while transporting while keeping the width of the sheetlike material substantially constant, and the sheeting material is transported in the first stretching region disposed on the downstream side of the preheating region. Is gradually expanded to stretch the sheet-like material in the width direction and the longitudinal direction, and the width of the sheet-like material stretched in the first heat setting region disposed on the downstream side of the first stretching region is substantially constant. Heat-fixed while being transported, and In the second stretching region arranged on the wake side of the region, while conveying the sheet-like material, the gripping pitch of the gripping device is gradually expanded to stretch the sheet-like material in the width direction and the longitudinal direction, In the second heat setting region disposed on the downstream side of the second stretching region, the stretched sheet-like material is heat-set while being conveyed while being kept substantially constant.

  Further, in at least one of the first stretched region and the second stretched region, the sheet-like material is made different in the longitudinal magnification of the gripping pitch of the link device at the left and right ends in the width direction of the sheet. Stretch the product.

  Furthermore, when the stretching region and the heat setting region connected to each other are one unit, in the stretching machine having two units, the longitudinal magnification of the gripping pitch of the link device located in the stretching region is set upstream. It is characterized by being set higher in the unit located downstream from the unit located. This is because the unit located downstream is stretched upstream and the sheet-like material is thinly stretched and is in a state of being easily stretched. is there.

  Although the expression that the tension acting on the sheet-like material is loosened in the first heat fixing region 110 is described above, the stretching force is eliminated by making the upper and lower guide rails parallel as shown in the figure, and the tension acting on the film is reduced. It is also possible to loosen or to completely relax by tilting the upper and lower guide rails toward the center of the sheet.

  Moreover, although the present Example is extending | stretching twice continuously with one extending | stretching machine, for example, the sheet-like material after the 1st extending | stretching is manually operated using the extending | stretching machine of 1 time with 1 unit | set. Then, it can be moved again to the entrance and re-gripped by the gripping device 202 to be stretched for the second time. However, it is necessary to cut the grip allowance at the time of the first stretching on both sides in the width direction of the sheet-like material after the first stretching, and to make a grip allowance for the second time, and the yield of the sheet-like product as a product deteriorates. . In addition, this leads to cutting work and moving work, resulting in poor production efficiency. On the other hand, in the present embodiment, since it is not necessary to cut the gripping margin, the yield of the sheet-like product is good, and this eliminates the need for cutting work and moving work, thereby improving the production efficiency.

  In this embodiment, both the first and second stretching regions are obliquely stretched, but the diagonal stretching is performed in one stretching region, and the other stretching region is linked at the left and right ends in the width direction of the sheet-like material. The left and right uniform stretch may be the same in the longitudinal magnification of the gripping pitch of the apparatus, and the first and second stretch regions may be left and right uniform stretch.In this case, by stretching in the vertical direction in small increments, Wrinkles can be prevented.

  A second embodiment of the present invention will be described with reference to FIG. FIG. 4 shows that the extension region 10 described above is moved by moving a plurality of link beds 3a connected by joints arranged in the extension region 10, and the interval between the guide rails 3 is changed to three stages. It is characterized in that it is subdivided into a stretching region 100, a first heat setting region 110, a second preheating region 90, and a second stretching region 101, and 11 is a second heat fixing region. In other words, if the preheating region, the stretching region, and the heat setting region that are connected are defined as one unit, two units are arranged.

  In the stretching region 10, the pitch of the grip position 201L at the left end of the isometric link above the sheet-like object center line (one-dot chain line) is set to P1 <P3 <P4 <P6 <P7, and below the sheet-like object center line. The pitch of the grip position 201R at the right end of the isometric link is set to P1 <P2 <P4 <P5 <P7. And the pitch of the width direction both ends is set with the relationship of P2 <P3 and P5 <P6.

  The present embodiment is almost the same as the operation and effect of the first embodiment. However, as a special effect, the second preheating region 90 is provided to operate with a temperature difference from the first heat fixing region 110. Is possible. That is, in the first heat setting region 110, the internal stress can be sufficiently removed by setting the temperature relatively low, and in the second preheating region 90 following this, the preheating is performed in a state where the temperature is set higher than this. By doing, it can prepare for smooth extending | stretching in the subsequent 2nd extending | stretching area | region.

  A third embodiment of the present invention will be described with reference to FIG. FIG. 5 shows that the extension region 10 described above is moved by moving a plurality of link beds 3a connected by joints arranged in this region 10, and the interval between the guide rails 3 is changed in three stages. It is characterized by being subdivided into a stretching region 100, a first heat setting region 110, a buffer region 17, a second preheating region 90, and a second stretching region 101. The relationship between the pitches P1 to P7 is the same as in the previous embodiment.

  The present embodiment is almost the same as the operation and effect of the previous embodiment. As a special effect, the buffer area 17 is provided. When the preheating, stretching, and heat fixing area is one unit, the buffer area Since the units can be completely separated by configuring the room for each unit via 17, the temperature management and arrangement of the units can be facilitated.

  A fourth embodiment of the present invention will be described with reference to FIG. FIG. 6 is characterized in that the arrangement of the guide rails 3 is changed vertically (up and down with respect to the center line of the sheet-like object) in the extension region 10 described above. That is, it is characterized in that the opening angle of the guide rails 3 arranged in the extending area in the extending region is made different on the left and right in the width direction of the sheet-like material. Specifically, the guide rail 3 at the left end (upward with respect to the center line of the sheet-like object) is arranged at an increased angle, and the guide rail 3 at the right end (downward with respect to the center line of the sheet-like object) is preheated without increasing the angle. It is in the position where the region 9 remains.

  This embodiment is almost the same as the operation and effect of the previous embodiment, but as a special effect, one (lower) of the upper and lower guide rails 3 is fixed, so that only the other guide rail 3 is opened. Since the angle is adjusted, the opening angle in the width direction can be finely adjusted, and the displacement of the isometric link can be finely adjusted, and the maximum inclination angle that does not cause wrinkles when the sheet-like material is obliquely stretched Useful when setting up.

  Applicable to all tenter type film stretching devices.

It is the figure which modeled the diagonal stretched state which concerns on Example 1 of this invention. It is the figure which modeled the diagonal stretched state at the same time when an inclination angle is enlarged. It is the figure which modeled the diagonal stretched state which is a specific structure of Example 1 of this invention. It is the figure which modeled the diagonally-stretched state which is a specific structure of Example 2 of this invention. It is the figure which modeled the diagonal stretched state which is a specific structure of Example 3 of this invention. It is the figure which modeled the diagonal stretched state which is a specific structure of Example 4 of this invention. It is a top view of the simultaneous biaxial stretching machine concerning the example of the present invention. It is a figure which shows the outline of a structure of the link apparatus of a simultaneous biaxial stretching machine similarly.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Sheet | seat-shaped extending | stretching machine, 2 ... Conveyance space, 3 ... Guide rail 4, 5 ... Endless link apparatus, 6, 7, 8 ... Sprocket, 9 ... Preheating area | region, 10 ... Extension area | region, 11 ... Heat setting area | region , 12 ... Nozzle, 13 ... Duct, 17 ... Buffer region, 20 ... Sheet-like material, 90 ... Second preheating region, 100 ... First stretching region, 101 ... Second stretching region, 110 ... First heat fixing region, 200 ... Link device, 201 ... Equal-length link, 202 ... Gripping device, 205 ... Rail on the outer peripheral side, 206 ... Rail on the inner peripheral side, 207, 208 ... Link shaft for joint, 209, 210 ... Link plate, 211, 212 ... Bearing holder, 213, 214...

Claims (6)

A plurality of linked links having gripping devices for gripping both left and right ends of the thermoplastic sheet-like material in the width direction are guided along a closed guide rail on a substantially horizontal plane, and the sheet-like material is guided through the guide rail. After stretching while transporting from the inlet side to the outlet side, it is equipped with a pair of endless link devices that travel back to the inlet side,
Each of the endless link devices includes a preheating region that conveys the sheet-like material disposed on the inlet side while maintaining a substantially constant width;
The sheet is disposed on the downstream side of the preheating region and conveys the sheet-like material while gradually spreading the guide rail for extending the sheet-like material in the width direction and the longitudinal direction by gradually increasing the gripping pitch of the gripping device. A stretch region provided with a shaped portion;
A heat fixing region that is arranged on the downstream side of the stretching region and transports the stretched sheet-like material while maintaining a substantially constant width;
At least a plurality of units of the stretched region and the heat setting region connected to each other are arranged,
A sheet-like material drawing machine characterized in that the enlargement magnification in the vertical direction of the gripping pitch of the link device located in the drawing region is varied between the left and right ends in the width direction of the sheet-like material.   2. The sheet-like material drawing machine according to claim 1, wherein at least a plurality of units of the preheating region, the drawing region, and the heat fixing region are connected.   3. The sheet-like material stretching machine according to claim 1, further comprising a buffer region between the plurality of units.   The sheet-shaped article stretching machine according to any one of claims 1 to 3, wherein the opening angles of the guide rails arranged in the shape of spreading at the end of the stretching area are made different from each other.   The longitudinal enlargement magnification of the gripping pitch of the link device located in the extension region is set higher in the unit located downstream than the unit located upstream. Sheet-like material stretching machine. A plurality of linked links having gripping devices for gripping both left and right ends of the thermoplastic sheet-like material in the width direction are guided along a closed guide rail on a substantially horizontal plane, and the sheet-like material is guided through the guide rail. After stretching while transporting from the inlet side to the outlet side, it is equipped with a pair of endless link devices that travel back to the inlet side,
Preheating while transporting the sheet-like material while keeping the width of the sheet-like material substantially constant in the preheating region disposed on the inlet side,
While conveying the sheet-like material in the first stretching region disposed on the downstream side of the preheating region, the gripping pitch of the gripping device is gradually expanded to stretch the sheet-like material in the width direction and the longitudinal direction,
In the first heat setting region disposed on the downstream side of the first stretching region, heat-fixed while transporting while maintaining the width of the stretched sheet-like material substantially constant,
In the second stretching region disposed on the wake side of the first heat setting region, the sheet-like material is conveyed while the sheet-like material is gradually expanded by increasing the gripping pitch of the gripping device. Stretched to
In the second heat setting region disposed on the downstream side of the second stretching region, heat-fixed while transporting while keeping the width of the stretched sheet-like material substantially constant,
In at least one of the first stretched region and the second stretched region, the sheet-like material is obtained by varying the longitudinal magnification of the gripping pitch of the link device at the left and right ends in the width direction of the sheet-like material. stretching method features and to Resid over preparative like material to stretching.

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