JPS6377729A - Driving method for simultaneous biaxial orientation machine for sheetlike material - Google Patents

Abstract

PURPOSE:To limit varying points of the tensile force and pressing force of sprockets thereby to stably feed a film in a mechanical feeding by adjusting the specified fine gap between an endless linkage and guide rails. CONSTITUTION:In a sheetlike material biaxial orientation machine which increases a grasping pitch in a flared state with respect to a moving direction, it is so driven that it is pressed by an inlet side sprocket 8 in a range of 1/5B in an orientation zone B, it is thereafter pulled by an outlet side sprocket 9, it is pressed by an outlet side sprocket 9 to 1/10G in a return zone G, it is then pulled by an intermediate sprocket 7, it is pressed by the sprocket 7 to 1/3. 2/3J in a link pitch adjusting zone J, and it is thereafter pulled by the sprocket 8. The restriction and interference with guide rails 4, 5 and 6 are alleviated.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention provides a simultaneous biaxial stretching system equipped with an endless link device that simultaneously and continuously stretches a plastic film or sheet in two axes in the longitudinal direction and the transverse direction. It is related to the device.

[Conventional technology]

As described in Japanese Utility Model Publication No. 45-6785, a conventional simultaneous biaxial stretching device equipped with an endless link device includes a sprocket added to the return side of the link device to provide a link pitch adjustment section, and a sprocket on the link shaft. Space rings are provided and the space rings are brought into contact with each other to transmit the driving force in the minimum pitch section, thereby reducing the driving force and smoothing the link drive. Also, Japanese Patent Publication No. 59-
No. 67015 proposes a completely endless rail for the purpose of high-speed and stable running, and in order to determine the running trajectory of the link device only by restraint by the guide rail. This method simplifies the drive system of the conventional method and allows the link device to run at high speed with constant tension applied, but the endless guide rail has a different appearance for each section corresponding to film processing. As the guide rail is heated to a certain temperature, the guide rail thermally expands over its entire length by approximately several tens of degrees, while the linkage device is also heated to a different temperature than the guide rail.

Because it is cooled, no consideration has been given to alleviating the restraining force due to differences in elongation due to mutual thermal expansion, as well as changes in the fitting of various parts of the link device over time, or interference with the guide rail due to elongation.

[Problem that the invention seeks to solve]

The above-mentioned conventional technology does not take into consideration interference and restraint due to the difference in thermal expansion between the link device and the guide rail, and has a problem in that stable operation cannot be performed.

An object of the present invention is to smoothly drive a link device restrained by a guide rail, thereby eliminating restraint due to the difference in thermal expansion between the guide rail and the link device and elongation of the link device.
The objective is to maintain a stable operating condition by alleviating interference E2.

[Means for solving problems]

The above object is achieved by adjusting and driving the relationship between the guide rail, the endless link device, and the sprocket that drives the link device to the limited conditions necessary for stable running of the endless link device.

[Effect]

The endless link device is pushed by the inlet sprocket to a range of 115B in the extension section B, then pulled by the outlet sprocket, and pushed by the outlet sprocket to the range of 1/IOG in the return section G, and then After that, it is pulled by the intermediate sprocket,
In the link pitch adjustment section J, 1. /3~2/3J
Since it is pushed in by the intermediate sprocket up to a range of 1 and then pulled by the inlet sprocket, restraint and interference due to differences in thermal expansion between the guide rail and the endless link device are alleviated.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. In FIG. 1, an unstretched flat film 1 is
The gripping device 3 provided on the endless link device 2 grips both side edges in the gripping section, heats it in the preheating section A, stretches it simultaneously in two directions vertically and horizontally in the stretching section B, and then stretches it in a predetermined direction in the heat treatment section C. The film is then heat-set at a temperature of , followed by shrinkage in a shrinkage section, cooled in a cooling section E, and then continuously advanced 4 degrees in the direction of the arrow through a film release section F. The endless linkage 2 is guided by guide rails 4,5°6 and sprockets 7,8,9 provided at both ends.
Driven by. The endless link passes through a return section G, an IJ adjustment section J, and then returns to a grip section K, forming an endless link device 2.

2 and 3 show details of the endless link device 2. FIG. It is formed by connecting the ends of a pair of outer links 12.13 and a pair of inner links 14.15 of equal length in a folded shape by link shafts 15a and 16b, and the link shaft 16b is meshed with the aforementioned sprocket. Bearing rollers 17 are driven by
and 18 are guide rails 4, 6 and 4, respectively.
It rolls along the groove formed by 5. 19 is a roller chain that regulates the maximum pitch of the endless link device 2;
0 is a space ring attached to the upper part of the bearing roller 17°18.

FIG. 2 shows a state in which each part of the link device 2 is completely opened, and the gripping pitch P of the film 1 is given by Pmax. At this time, the dimension H between link axes is Hm. In this state, the bearing roller 17.
18 is in a state where it is restrained by Hm, and a state in which the roller chain 19 is pulled by a sprocket in an unrestrained state. FIG. 3 shows a state in which the bearing roller 17.18 is restrained by the guide rails 4, 5.6, and the gripping pitch of the film 1 is Pi.

The gripping pitch P in the gripping section K is calculated as P (H = H
max ), the P order is the adjacent space ring 2
0 are in contact with each other, and the sprocket 8 is driven to push the space ring 20. After traveling in the preheating section A, in the stretching section B, the endless link device 2 runs while gradually opening from the state of Hmax due to the regulation of the guide rails 4, 5.6, and at the end of the stretching section B, it reaches Hm, and the gripping pitch is changed. P varies from Pm to Pmax.

As a result, the film 1 is stretched in the machine direction (longitudinal direction), and at the same time, the guide rails 4, 5.6 are set to gradually open in a direction perpendicular to the machine direction of the film 1. is simultaneously stretched in the perpendicular direction (lateral direction). In the heat treatment section C, the vehicle travels after simultaneous longitudinal and transverse stretching has been completed, and in the shrinkage section, the guide rail 4 is moved again.
, 5.6, the film gripping pitch P is reduced by only a few percent, and after passing through the cooling section E and the film releasing section F, the rotation of the sprocket 9 causes the film to return to the section G.

It constitutes an endless link that returns to the film gripping section K via the link pitch adjustment section J. The relationship between this series of endless link devices 2 and the guide rails 4, 5, 6 is regulated in all sections, and if the link device 2 is always running in a tensioned state in any part, it will cause abnormal interference as described above. In order to solve this problem, large-scale auxiliary equipment such as adding an automatic adjustment mechanism is required. On the other hand, stable running of the film 1 cannot be expected only by providing a small gap between the guide rail 4, 5, 6 and the endless link device 2 in each section.

In sections A, B, C, D, B, and F, the endless link device 2 is pushed in by the sprocket 8 and pulled by the sprocket 9, but the positions where the pushing force and the pulling force change are as follows: , 9 and the number of link devices between them, and this change point
Adjust to ~115 B, preferably 1/10 B. In the return section G, the endless link device 2 is pushed by the sprocket 9 and pulled by the sprocket 7, but the change point Y between the pushing force and the pulling force is preferably O to 1/IOG on the side of the threaded rod 9 in the return section G. is 1150G
Adjust to. In the link pitch adjustment section J, the endless link device 2 is pushed in by the sprocket 7, and is pulled by the sprocket 8 while rapidly reducing the link pitch P. However, the point of change Z between the pushing force and the pulling force is in the link pitch adjustment section. Of J, sprocket 7 side 1/3~2/
Adjust to 3 J, preferably 315 J.

Even if sections C, D, and E are not required depending on the purpose of stretching the film, it is best to make the above adjustments.

〔Effect of the invention〕

According to the present invention, by adjusting the minute gap between the endless link device and the guide rail, and by limiting the change points of the pulling force and pushing force of each Su-8 Prokerato, the mechanical running state can be adjusted. In addition, it has the effect of allowing the film to run stably.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a film simultaneous stretching device showing one embodiment of the present invention, and FIGS. 2 and 3 are detailed plan views of the endless link device.

Claims (1)

[Claims] 1. A plurality of gripping devices for gripping both edges of a thermoplastic resin sheet-like object are provided in an endless link device arranged at both ends of the sheet-like object, and the endless link device is a plurality of pieces formed in a folded shape. It is driven by a sprocket on the inlet side of the sheet-like object, and is guided by a guide rail arranged in a manner that spreads toward the end in the direction of movement.By gradually increasing the gripping pitch, the sheet-like object can be gripped in both the vertical and horizontal directions. In a simultaneous biaxial stretching apparatus for a sheet-like material configured to simultaneously stretch the sheet-like material, remove the sheet-like material, and return the sheet-like material to an inlet-side sprocket by being driven by an outlet-side sprocket, the endless link device The stretching section B, which is formed to widen at the end, is pushed in by the inlet sprocket 8 to a range of 1/5B from the entrance of the stretching section, and after that, it is pulled by the outlet sprocket 9, and after the sheet-like material is removed, it is pushed from the outlet sprocket 9. It is pushed by the outlet side sprocket 9 to a range of 1/10G from the outlet side sprocket 9 in the return section G up to the intermediate sprocket 7 on the inlet side of the sheet-like material, and after that, it is pulled by the intermediate sprocket 7,
In the link pitch adjustment section J between the intermediate sprocket 7 and the inlet sprocket 8, the link is pushed in by the intermediate sprocket 7 to a range of 1/3 to 2/3 J from the intermediate sprocket 7, and thereafter pulled by the inlet sprocket 8. 1. A method for driving a simultaneous biaxial stretching device for sheet-like materials, characterized in that: