JPH0153177B2 - - Google Patents

Description

Detailed Description of the Invention [Industrial Application Field] The present invention aims to improve the physical and mechanical properties of a sheet-like material, such as a thermoplastic synthetic resin film, in the longitudinal direction ( The present invention relates to a stretching device for sheet-like materials using a stretching link device for stretching in the longitudinal direction) and/or the lateral direction.

[Prior Art] Conventionally, as a simultaneous biaxial stretching device using a link, there is a system applying a pantograph link proposed in Japanese Patent Publication No. 5560-1983, and a method applying a pantograph link proposed in Japanese Patent Publication No. 1987-5560,
A typical example is an application of the folded scale link proposed in Publication No. 7155.

However, with these conventional methods, abnormal force interference occurs between the drive sprocket and the guide rail that guides the special link, so the guide rail has to be cut once at the drive sprocket. Therefore, it became necessary to transfer the special links to the guide rails before and after the drive sprocket, and there was a problem in that the speed increase was suppressed due to this transfer. In addition, in a normal running section, the orientation of the holding body for the sheet-like object changes depending on the opening degree of the special link, and the stretching tension of the sheet-like object, the force for running the running object, and the force due to the own weight of the special link, etc. Since the balance between the two was not maintained, there was a problem that the high-speed stability of stretching and running was lacking.

In order to compensate for the above-mentioned drawbacks, the present applicant previously proposed in Japanese Patent Application No. 134349/1983 that a pantograph link unit was constructed from link members of two types, each having a long and short length between supporting points, and these were connected to each other. By passing the short links fully extended through the drive sprocket, abnormal force interference between the drive sprocket and the guide rail at the drive sprocket is prevented, and the positional relationship is always perpendicular to the running direction. By providing a sub-link for holding and providing a gripping body for the sheet-like object on the sub-link, the direction of the gripping body is prevented from changing depending on the opening degree of the special link, and the mechanical balance is taken into consideration. A pantograph link mechanism has been proposed, which promises faster speeds than conventional ones.

[Problems to be Solved by the Invention] However, even with the proposed device described above, if the aim is to run at higher speeds, the force applied to the guide rails that determine the degree of bending and stretching of the pantograph links and to each link increases. Therefore, in order to achieve stable high-speed running, a guide rail with a larger shape that does not deform even at high speeds is required, and each link accordingly also needs to be larger in size. As a result, one pantograph link unit becomes large, and there is a limit to adjusting the degree of bending and stretching of the pantograph to reduce the pitch between the sheet-shaped object gripping bodies, and the initial gripping pitch of the sheet-like object at the starting end of the stretching device becomes smaller. As the stretching progresses, a constricted portion occurs in the lateral direction in the portion of the sheet-like object that is not supported by the gripper, resulting in uneven thickness of the sheet-like object and the product. The disadvantage was that the yield of

Furthermore, the guide rail that regulates the degree of bending/extending of the pantograph link unit may have slight adjustment errors, manufacturing errors, etc., and these errors cause fluctuations (changes) in the degree of bending/extending while the pantograph is running. The influence of this error becomes more pronounced as the degree of bending and stretching of the pantograph link unit in the direction of reducing the pitch between the gripping bodies of the sheet-like object increases, and the higher the speed is, the greater the variation in the degree of bending and stretching of the pantograph due to the above-mentioned error becomes. Therefore, from this point of view, there is a limit to reducing the pitch between the gripping bodies at the starting end of the stretching device only by adjusting and setting the degree of pantograph bending and stretching using the guide rail. In order to do this, it is desirable to keep the degree of pantograph bending and stretching to a certain degree small even at the starting end of the stretching device, and to reduce the pitch between the gripping bodies.

The present invention aims to improve the conventional special link running type that has these drawbacks, and proposes a new link mechanism.The purpose of this invention is to easily achieve higher speeds, and to achieve stable running and stretching even at high speeds. The object of the present invention is to provide a stretching device that can perform the stretching process.

[Means for Solving the Problems] The sheet-shaped material stretching apparatus of the present invention in accordance with this object is a link unit in which a plurality of links are connected in a quadrilateral pantograph shape so as to be able to bend and stretch each other via a fulcrum, and It consists of an endless chain link connected to a
As a seed, links of the same length are connected so as to be adjacent to each other, and a pair of links of the same length are rotatably connected via a fulcrum to the adjacent long links between the adjacent pantograph link units, and an intermediate link is connected. A first sub-link is provided between the fulcrum connecting the long links and the fulcrum connecting the short links in the pantograph link unit to maintain a positional relationship perpendicular to the running direction, and the long link and the short link are connected to each other. A second sub-lik is provided between the fulcrum that connects the fulcrum and the fulcrum of the pair of links in the intermediate link to maintain a positional relationship perpendicular to the traveling direction,
A guide element that supports the endless chain link in a movable manner is engaged with at least one of the two sub-links, and is provided independently of the guide element in the pantograph link unit in a positional relationship that determines the degree of bending and stretching of the pantograph link. A pair of guide rails for guiding the inductor are arranged in accordance with the longitudinal or lateral elongation of the sheet-like object to be stretched, and the first sub-link and the second It is equipped with a pair of left and right stretching mechanisms in which gripping bodies for gripping the ends of the sheet-like material are arranged on sub-links of the sheet-like material.

[Examples] Examples of the present invention will be described in detail below with reference to the drawings, and the effects of the present invention will also be explained.

FIG. 1 is an overall schematic plan view of a stretching device according to an embodiment of the present invention. In the figure, a film (or sheet) 1 to be stretched is carried in in the direction of the arrow, held by a gripper 41 that grips the end of the film, and stretched in the vertical and horizontal directions while being moved. The gripping body 41 is installed on each of the first and second sub-links 40 and 43, which are installed above the special pantograph link 10 and the intermediate link 16 in a direction perpendicular to the traveling direction of the links 10 and 16. Hereinafter, the sub-link provided on the special pantograph link 10 will be referred to as a first sub-link 40, and the sub-link provided on the intermediate links 15 and 16 will be referred to as a second sub-link 43. The special pantograph link 10 includes a pair of inductors 21,
22 is installed, and the running path of the guides 21 and 22 is determined by a pair of endless guide rails 23 and 24. In addition, special pantograph link 10
is driven by a drive sprocket 50 located on the exit side. Although not shown in this figure, a pre-tensioning mechanism is incorporated in this chain running system as well as a general chain running system, and this mechanism allows this special pantograph link 10 to
1 and 22 are run without being lifted off the endless rails 23 and 24. The endless rails 23 and 24 are located on the entrance side, with a pantograph link 10 and an intermediate link 1.
5 and 16 are arranged in a contracted state in the traveling direction and in an enlarged state on the exit side, and as shown in the figure, a pair of left and right sides are arranged in a shape that widens towards the end.

2, 3, and 4 are enlarged views of the special pantograph link part of FIG. 1 in order to make the details of the present invention clearer. The figure is a plan view, and FIG. 4 is a longitudinal sectional view.

2, 3, and 4, the special pantograph link 10 is composed of two types of links, long and short, namely short links 11, 12a, 12b and long links 13a, 13b, 14a, 14b. are connected by pins A, B, and C. In addition, there are inductors 21 above and below pin A.
a, 21b, and above and below pin C are inductors 22a,
22b is attached. There are two types of inductors: sliding types and rotating types. In this figure, a rotating type consisting of a rotating body supported via a bearing is shown in consideration of high-speed stability.

The inductors 21a, 21b, 22a, 22b are guided by endless rails 23a, 23b, 24a, 24b.

The endless rails 23a, 23b are attached to the rail 100, and the endless rails 24a, 24b are attached to the rail 100.
A rail 20 laterally slidably supported on 00
0 as shown in FIG. 4, has an adjustment mechanism outside the system (not shown) that can change the relative position of the rail 100 and the rail 200, and can be arranged in a spreading shape (not shown). is also held outside the system.

Further, a first sub-link 40 is connected to the pins A and B, and the first sub-link 40 is connected in a fixed manner for pin A and in a slidable manner for pin B. Secondary link 40
By slidably positioning the pin B in the long holes 40a and 40b provided in the pantograph link 10, a mechanism is created in which the first sub link 40 can always maintain a direction perpendicular to the running direction of the special pantograph link 10. .
On the first auxiliary link 40, there is a gripping body 41 that grips the end of the film, and guides 42a, 42b that bear various vertical loads during traveling, including the own weight of the special pantograph link 10, the first auxiliary link 40, etc. 4
2c and 42d are attached, and both move on the rails 100 and 200. The guides 42b, 42c, 42d are the first sub-link 40
It is not limited to the top, but may be on at least one of the first sub-link 40 and the second sub-link 43. Also, guide elements 42a, 42b, 42c, 4
Similar to the inductors 21a, 21b, 22a, and 22b, 2d can be installed as both a sliding type and a rotating type. The representative figure shows a rotating type consisting of a body.

Also long links 13a, 13b, 14a, 14b
Intermediate links 15a, 15b and 16a, which are half the length of the long links 13a, 13b, 14a, 14b, are rotatably mounted at the intermediate points of
16b are connected. Intermediate link 15a, 1
5b, 16a, 16b are intermediate links 1 similarly provided to adjacent pantograph links 10.
6a, 16b and 15a, 15b via pins D, and the long links 13a, 13b, 14a, 14b of the pantograph link 10 and the intermediate links 15a, 15b, 16a, 16b form a pantograph-like link mechanism. is configured. Furthermore, a second sub-link 43 is connected to the pins C and D, and the second sub-link 43 is fixedly connected to the pin D and slidable to the pin C. Secondary link 4
By slidably positioning the pin C in the elongated holes 43a and 43b provided in the first sub-link 4
0, special pantograph link 10
The mechanism is such that the second sub-link 43 can always maintain a direction perpendicular to the traveling direction of the vehicle. A gripper 41 is attached to the second sub-link 43 and the first sub-link 40 to grip the end of the film. An annular endless chain link is constructed by continuously connecting the link mechanism constructed by connecting the intermediate links 15a, 15b, 16a, and 16b to the special pantograph link 10 in this way.

As can be seen from the above explanation, compared to the pantograph link that was previously proposed by the applicant and was composed of two types of links, long and short, with a sublink provided,
A feature of the present invention is the provision of an intermediate link and a second sub-link, and in this embodiment, a structure in which the second sub-link is connected to the intermediate link has been described.

Next, the functions and actions of each part will be explained in order to further clarify the technical points of the present invention.

First of all, the biaxial stretching device uses guide rails 23a, 23b, 24a, and 24b that determine the degree of bending and stretching of the special pantograph link 10 as it runs at high speed.
and the force developed on each link increases. Therefore, in order to achieve more stable running at high speeds, it is necessary to use guide rails 23a, 23b, 24a, 24b and link members that do not deform even at high speeds, that is, have high rigidity and strength. However, the guide rail 23
In order to increase the rigidity of the inductors 21a, 22a and 21b, 22
It is necessary to take a large interval b, and each link member inevitably becomes long. Generally, when stretching an unstretched film, a lateral constriction occurs in the ungridded portions on both sides of the film, so it is desirable to reduce the initial pitch of the film as much as possible in terms of film quality. If the pitch is made smaller, the guide rails 23a, 2
3b, 24a, 24b long link 13a, 13b,
The angle formed by 14a and 14b increases, and as a result, the load applied to the link increases, causing a vicious cycle of deformation of the guide rail.

In addition, the guide rails 23a, 23b, 24a, 24
When the angle between b and the long links 13a, 13b, 14a, 14b increases, the guide rails 23a, 23
A slight lateral positional error of the pantograph links 10, 24a, and 24b causes a large change in the degree of bending and stretching of the pantograph link 10, and this change has the disadvantage that the gripping pitch of the sheet-like object changes significantly.

The present invention solves the above drawbacks by providing intermediate links 15a, 15b, 16a,
16b, and a grip body 41 is also attached to the intermediate link portion.
By arranging this, the initial gripping pitch can be shortened to 1/2 compared to conventional ones. In other words, if the guide rail is set to a predetermined gripping pitch on the entrance side (starting end side) of the stretching device, the angle between the guide rail and the long link can be small. As a result, even when traveling at high speed, there is less variation in the degree of bending and stretching of the pantograph link 10 due to the lateral position error of the guide rail, and high speeds can be easily achieved. , 43, the stretching load, etc. is transmitted through the two sub-links, so the load generated on each link can be distributed and reduced compared to the case where there is only one sub-link. As a result, the necessity of increasing the strength of each component is alleviated, the weight of the component is reduced, and the force applied to each inductor 21a, 21b, 22a, 22b is also reduced, resulting in a significant reduction in running resistance.

The second feature is the special pantograph link 1.
On the first and second sub-links 40, 43 (on at least one of the sub-links) that maintain the direction perpendicular to the running direction of the vehicle, guide elements 42a, 42b, 42c, which receive vertical loads when all the links are running, are provided. By adding 42d, guide elements 42a, 42b, 42
c and 42d always substantially match the running direction of the special pantograph link 10, and especially when the guides 42a, 42b, 42c, and 42d are used as rotors, the rotating direction of the rotor is the same as that of the special pantograph link 10. The point is that it can match the running direction of the vehicle. By making it possible to use the rotor smoothly, it becomes easier to increase the speed even more. Also secondary link 4
0, 43, the orientation of the gripping body 41 does not substantially change due to the bending of the special pantograph link 10. This eliminates the possibility of film gripping, which can cause film tearing, especially when traveling at high speeds. It is also possible to create a mechanism that does not generate force such as undue twisting at the parts.

The third feature is that by arranging each member almost vertically symmetrically with respect to the film plane F-F (shown in Figure 4), the stresses generated in each part are comprehensively balanced, resulting in distortion, etc. This prevents the generation of unreasonable couples, and it is also possible to exhibit extremely excellent high-speed performance. In addition, since the driving force is transmitted only by the special pantograph link 10,
The intermediate links 15a, 15b, 16a, and 16b may be of any material as long as they can sufficiently withstand the stretching stress of the film.

The above description has been made using a biaxial stretching machine with good high-speed stability as an example of the present invention, and the present invention is not limited thereto in any way. That is, as a very special example, the mechanism of the present invention is
By appropriately adjusting the distance between the pair of guide rails 23 and 24, the machine can also be used as a longitudinal stretching machine.

Furthermore, to describe the gist of the present invention, the embodiments shown in FIGS. 1 to 4 show design examples that place particular emphasis on high-speed stability. There is no need to be as heavily armed as in the example. That is, when the stretching stress during film stretching is small, the inductors 21a, 22a and 42a, 4 at the upper part of the film surface FF (FIG. 4)
2c can be omitted, and the rails 23a and 24a that guide it can also be omitted.
If further developed, it is also possible to divide the second sub-link 43 into upper and lower parts and omit the upper part.

In addition, the first sub link 40 and the special pantograph link 10, the second sub link 43 and the intermediate link 15
In this embodiment, the method for attaching the a, 15b, 16a, and 16b is also explained based on a case where the chain composite tension for running the special pantograph link 10 is sufficiently larger than the film stretching tension. That is, the degree of bending and stretching of the special pantograph link 10 does not change under the influence of the film stretching tension, and each inductor 21a, 21b, 22a, 2
2b is endless rail 23a, 23b, 24a, 24
This is an explanation of a case that does not emerge from b, and if this premise breaks down, a certain amount of general engineering measures will naturally be required. For example, by fixedly connecting the first and second sub-links on the pins B and C sides and sliding the pins A and D sides, all the film stretching stress is transferred to the inductor 22.
a, 22b and the endless rails 24a, 24b, and a force is applied to the special pantograph link 10 so as to extend the pantograph link 10 in the running direction with only the tension of the running system, so that the inductors 21a, 21b, 22a , 22b are always in contact with the endless rails 23a, 23b, 24a, 24b,
Each inductor of the pantograph link 10 will travel without being lifted up.

[Effects of the Invention] As described above, when using the sheet-shaped material stretching apparatus of the present invention, an intermediate link is provided in a pantograph link consisting of two types of long and short links, and the pantograph link and the intermediate link are connected. By providing first and second sub-links that maintain a position perpendicular to the running direction of the endless chain link, the force applied to the link device is dispersed and the stress generated in each link is significantly reduced. Since the mounting pitch of the gripping body is significantly reduced, it is possible to suppress the increase in the size of the link device due to higher speeds, and to prevent the narrowing of the edge of the sheet-like object and the gripping body due to stretching. Pitch fluctuations can be suppressed, and sheet-like materials can be stretched at high speed and stably.

[Brief explanation of drawings]

FIG. 1 is a plan view of an embodiment of the present invention applied to a film stretching device, FIG. 2 is a perspective view of a pantograph link in the device shown in FIG. 1, and FIG. 3 is a pantograph link in the device shown in FIG. FIG. 4 is a longitudinal cross-sectional view taken along the line -- of the device shown in FIG. 3. 1...Film, 10...Special pantograph,
11, 12a, 12b... short link, 13a, 1
3b, 14a, 14b...Long link, 15, 16
...Intermediate link, 15a, 15b, 16a, 16
b...Intermediate link, 21, 22...Inductor, 21
a, 21b, 22a, 22b...inductor, 23,
24...Guidance rail, 23a, 23b, 24a,
24b...Guidance rail, A, B, C, D, E, F
...Pin, 40...First sub link, 41...Gripper, 42a, 42b, 42c, 42d...Guide, 43...Second sub link, 50...Drive sprocket, 100,200...Rail .

Claims (1)

[Claims] 1. A link unit in which a plurality of links are connected in a quadrilateral pantograph shape so as to be able to bend and extend each other via a fulcrum, and is composed of an endless chain link connected in an annular manner, and the fulcrums on both sides of the four-sided link members constituting the pantograph link unit length of time 2
As a seed, links of the same length are connected so as to be adjacent to each other, and a pair of links of the same length are rotatably connected via a fulcrum to the adjacent long links between the adjacent pantograph link units, and an intermediate link is connected. A first sub-link is provided between the fulcrum connecting the long links and the fulcrum connecting the short links in the pantograph link unit to maintain a positional relationship perpendicular to the running direction, and the long link and the short link are connected to each other. A second sub-link that maintains a positional relationship perpendicular to the traveling direction is provided between the fulcrum that connects the fulcrum and the fulcrum of the pair of links in the intermediate link, and an endless chain link is provided in at least one of the sub-links. engaging a guide element that is movably supported, and engaging an inductor provided independently of the guide element in a positional relationship that determines the degree of bending and extension of the pantograph link with the pantograph link unit;
A pair of guide rails for guiding the inductor are arranged according to the degree of elongation in the longitudinal or lateral direction of the sheet-like object to be stretched, and the sheet-like object is connected to the first sub-link and the second sub-link. A stretching device for a sheet-like material, which is equipped with a pair of left and right stretching mechanisms each having a gripper arranged to grip the end portion.