JPH088099Y2 - Tenter clip device - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tenter clip device used in a lateral stretching device for a film, and more particularly, a plurality of clips for holding the film are rotatably connected by a chain link and the clips are guided. The present invention relates to a tenter clip device adapted to run along a rail.

[0002]

2. Description of the Related Art Generally, when a resin film is manufactured, the film is stretched in the machine direction and the transverse direction.
A tenter clip device is often used for the lateral stretching. The tenter clip device grips both side edges of the film with a large number of clips, and while applying a lateral force, that is, a width direction to the film by the clips,
It is designed to run in the feeding direction. FIG.
It shows a transverse stretching device using such a tenter clip device. In the lateral stretching device, a large number of clips 01, 01, ... Are connected endlessly by chain links 02, 02 ,. Then, two sets of such connections are arranged facing each other on both sides of the film 03. The clip 01 is configured to be driven and driven in the arrow direction by an appropriate drive device along the guide rail 04. The guide rail 0
In No. 4, the width between them is narrow on the upstream side of the film forming machine 05 side, widened on the way, and widened on the downstream side.
In such a transverse stretching device, the film forming machine 05
The film 03 extruded from the film is clamped at both side edge portions by the clip 01 and sent to the downstream side, and is laterally stretched by being laterally widened therebetween.

A typical example of such a tenter clip device is disclosed in Japanese Utility Model Publication No. 2-9950. In the tenter clip device, as shown in FIG. 4, the film 03 is held by the tip of the clip 01. That is, a clip lever 06 is provided at the tip of the clip 01, and the side edge of the film 03 is gripped by the clip lever 06. Then, the clip 01 is made to travel along the guide rail 04 by the horizontal guide roller 07 attached to the rear end portion, that is, the side opposite to the film. The chain link 02 is rotatably connected to each clip 01 in a horizontal plane. The connection center T is located between the film gripping point C of the clip 01 and the guide rail 04 in plan view. With such an arrangement, the film 03
Since it is possible to match the surface of the film with the center surface of the guide roller 07, it is possible to apply an accurate lateral stretching force to the film 03.

[0004]

However, in the case of such a tenter clip device, the film gripping point C of the clip 01 has a connection center T of the chain link 02 to the clip 01 and a guide rail when viewed in plan view. Will be located inside the center line L, that is, on the film 03 side. On the other hand, in the transverse stretching device as described above, the narrow film 0 extruded from the film forming machine 05 is used.
Because clip 3 is grasped and fed while widening, clip 01
It is inevitable that a curved portion will be generated in the traveling route of. Therefore, when a tenter clip device in which the film gripping point C is located inside the chain link connection center T is used in the lateral stretching device, as shown in FIG. 4, the curve of the traveling path of the clip 01 is curved. In the section, a difference occurs between the traveling speed V of the film gripping point C and the traveling speed V ′ of the chain link connecting center T. As a result, even if the chain link 02 is driven at a constant speed, the film 03 is excessively stretched or shrunk between the adjacent clips 01, 01, and the stretching or shrinkage causes the molecular arrangement of the film raw material to change. Distortion occurs, and partial stretch unevenness remains on the stretched film 03. Further, in the case of the tenter clip device in which the guide rail 04 is arranged on the rear end side of the clip 01 as described above, the guide roller 07 rolling along the guide rail 04 is attached to the rear end portion of the clip 01. Therefore, the clip 01 becomes long in the width direction of the film 03. Therefore, in order to prevent adjacent clips 01, 01 from interfering with each other in the curved portion of the travel route, it is necessary to increase the interval between the clips 01, 01. However, if the distance between the adjacent clips 01, 01 is increased, the film 03
The portion to which the transverse stretching force is applied becomes sparse, and uniform stretching cannot be obtained.

The present invention has been made in view of the above problems, and a first object of the present invention is to obtain a tenter clip device capable of eliminating local expansion and contraction during the running of a film. Is. The second aspect of the present invention
The purpose of (1) is to obtain a tenter clip device which can reduce the distance between clips, and thereby can carry out uniform transverse stretching of the film.

[0006]

To achieve this object, in the present invention, guide rails are provided above and below the clip, and the center line of the guide rail and the connecting center of the chain link to the clip are both Are also arranged in the same vertical plane as the film grip point of the clip.

[0007]

As described above, when the film gripping point of the clip and the chain link connecting center are arranged in the same vertical plane,
The film gripped by the clip is fed at the same speed as the chain link. Therefore, if the chain link is driven at a constant speed, the film is also fed at a substantially constant speed, and it is possible to prevent the film from being excessively stretched or contracted while the clip travels along the curved path. Further, by disposing the guide rails above and below the film gripping point of the clip, the center line of the guide rails can be located in the same vertical plane. Then, by doing so, the lateral stretching force set by the guide rail can be accurately applied to the film. Moreover, by arranging the guide rails above and below the clip, the length of the clip in the film width direction can be shortened, so that the interval between adjacent clips can be reduced and the chain link can be shortened. Not only can it be made lightweight and compact, but it is also possible to apply uniform transverse stretching to the film.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 is a vertical sectional view of a main part showing an embodiment of a tenter clip device according to the present invention, and FIG. 2 is a cutaway plan view thereof. As is clear from these figures, the clip 1 of this tenter clip device has a pair of arms 2 and 2 on the upper part, and the lower part is formed as a clip base 3.
The clip body 4 has a substantially U-shape when viewed from the side. The arm 2 of the clip body 4 is provided with a bracket 5 extending downward.
The clip lever 6 is rotatably supported in the vertical direction by the lower end portion of the. The clip lever 6 is urged by a spring 7 so as to rotate clockwise in FIG. The clip body 4 is located on the side of the film 8 that is extruded from the film forming machine and stretched in the lateral direction. The film 8 is guided from the open side of the clip body 4 onto the clip base 3 when the clip lever 6 is rotated counterclockwise against the spring 7. By rotating the clip lever 6 in the clockwise direction, the side edge of the clip lever 6 is sandwiched between the tip 6a of the clip lever 6 and the clip base 3 and grasped. The tip 6a of the clip lever 6 has a certain length in the feeding direction of the film 8. Therefore, the film 8 is gripped by a length corresponding to the length of the tip 6a. That is, the film gripping point C of the clip 1 is formed long in the feeding direction of the film 8.

An upper horizontal guide roller 9 is attached to the upper surface of the arm 2 of the clip body 4, and a lower horizontal guide roller 10 is attached to the lower surface of the clip base 3. The guide rollers 9 and 10 are rotatably supported around their central axes by vertical shafts 11 and 12 provided on a vertical plane H including the film gripping point C of the clip 1. And those guide rollers 9,
10 is adapted to roll on the inner surfaces of channel-shaped guide rails 13 and 14 arranged above and below the clip 1. The center line L of the guide rails 13 and 14 is
It is arranged so as to be located substantially in the same vertical plane H as the film gripping point C of the clip 1. Further, the clip base 3 of the clip body 4 is notched on the side opposite to the film 8, and a vertical guide roller 15 is rotatably supported on the end face thereof. The guide roller 15 rolls on the upper surface of the side wall 14a of the lower guide rail 14. In this way, the clip 1 is guided by the upper and lower guide rails 13 and 14 and travels along the center line L thereof. The guide rails 13 and 14
Is an endless one arranged on both sides of the film 8 as in the conventional one, and the width between them is narrow on the film molding machine side, that is, on the upstream side, widened in the middle, and widened on the downstream side. Is being done.

As shown in FIG. 2, adjacent clips 1 and 1 are rotatably connected to each other in a horizontal plane by relatively short chain links 16 and 17. The connecting portions of the chain links 16 and 17 to the clip 1 are vertical shafts 11 and 12 that support the upper and lower horizontal guide rollers 9 and 10. In this way, the connection center T of the chain links 16 and 17 to the clip 1 is located in the same vertical plane H as the film gripping point C of the clip 1. In this way, the tenter clip device sequentially connects a large number of clips 1, 1, ... In this manner and connects them endlessly like the conventional one, and guide rails 13, 13 arranged on both sides of the film 8 respectively. ; 14,
It is constituted by making it run along with 14.

Next, the operation of the tenter clip device thus constructed will be described. The clips 1, 1, ... Of the tenter clip device are driven in the same manner as conventional ones, and the side portions of the film 8 are made to run in the feeding direction of the film 8. When the clip 1 approaches the side portion of the film 8 from the upstream side of the film 8, a force for rotating the clip 1 in the counterclockwise direction in FIG. 1 is applied to the clip lever 6 of the clip 1 against the spring 7.
Then, when the side edge portion of the film 8 is inserted onto the clip base 3, the pressing force applied to the clip lever 8 is removed. Then, the clip lever 6 is rotated by the urging force of the spring 7, and the side edge portion of the film 8 is gripped by the clip lever 6 of the clip 1 and the clip base 3. Each clip 1, 1, ... is a guide rail 1
Guide rails 1 which are guided by 3, 14 and face each other
3, 13; 14 and 14 are widened on both sides in the widened portion. Thereby, transverse stretching is applied to the film 8.

At this time, since the guide rails 13 and 14 are curved at the extension start point and the extension end point, the clip 1,
, 1 run along a curved path, but since the guide rails 13 and 14 are arranged above and below the clip 1, the length of the clip 1 in the film width direction is reduced. Even in the curved portion, adjacent clips 1 and 1 do not interfere with each other. Therefore, the distance between the clips 1 and 1 can be reduced. Then, since the distance between the clips 1 and 1 is reduced as described above, a lateral stretching force is densely applied to the film 8 along the feeding direction thereof. Therefore, the film 8 is stretched laterally almost uniformly. Further, since the guide rails 13 and 14 are disposed above and below the film gripping point C, the lateral stretching force set on the guide rails 13 and 14 is accurately applied to the film 8.

Further, the film gripping point C of the clip 1 is the center T where the chain links 16 and 17 are connected to the clip 1, that is, the vertical plane H which is the same as the axis of the vertical shafts 11 and 12.
Since it is arranged above, even when the clip 1 travels along the curved path, the film gripping point C thereof moves at the same speed as the chain links 16 and 17.
Therefore, if the chain links 16 and 17 are driven at a constant speed, the film 8 is not excessively stretched or shrunk, and uneven stretching due to local distortion is prevented. Thus, this tenter clip device makes it possible to obtain a film which has been uniformly stretched in the transverse direction.

[0014]

As is apparent from the above description, according to the present invention, the center of connection of the chain link to the clip is located in the vertical plane substantially the same as the film gripping point of the clip. Even in the curved path portion of the clip, the film is fed at the same speed as the clip, and the film is not stretched or contracted in the feeding direction. Therefore, it is possible to prevent partial stretching unevenness from occurring in the stretched film. In addition, the guide rails that guide the clip are placed above and below the clip, and the center line of the guide rail is positioned in the vertical plane substantially the same as the film gripping point of the clip. While being added, the length of the clip in the film width direction can be reduced. Therefore, the distance between adjacent clips can be reduced, the entire device can be made compact, and the film can be uniformly stretched laterally. Thus, this tenter clip device makes it possible to obtain a transversely stretched film of good quality with a good yield.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of essential parts showing an embodiment of a tenter clip device according to the present invention.

FIG. 2 is a cutaway plan view of a main part of the tenter clip device.

FIG. 3 is a schematic plan view showing an example of a lateral stretching device using a conventional tenter clip device.

FIG. 4 is a schematic plan view for explaining a problem in the conventional tenter clip device.

[Explanation of symbols]

 1 clip 4 clip body 6 clip lever 8 film 9 upper horizontal guide roller 10 lower horizontal guide roller 11, 12 vertical shaft 13 upper guide rail 14 lower guide rail 15 vertical guide roller 16, 17 chain link C film gripping point H vertical surface L Guide rail center line T Chain link connection center

Claims (1)

[Scope of utility model registration request] 1. A tenter clip in which a large number of clips for gripping side edges of a film are sequentially rotatably connected via a chain link in a horizontal plane and the clips are made to run along a guide rail. In the device; the guide rails are provided above and below the clip.
Ri, the center line of the guide rails, and coupling the center of the chain links and the clip, both characterized in that it adapted to be located in substantially the same vertical plane as the film holding point of the clip, Tenter clip device.