JPS6333875Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a winding device for a film made of synthetic resin, particularly thermoplastic resin such as polypropylene.

[Prior art and its problems]

In general, in order to continuously wind up a film made from synthetic resin raw materials such as polyester, polypropylene, polyamide, etc. as a roll-shaped film winding body, a film winding drum is driven and the film winding layer is wound on the winding drum. A center-wind winding device that does not allow anything to touch the surface.
A surface wind type winding device that rotatably supports a film winding drum without driving it, brings the surface of the film winding layer into contact with a driven surface drive roll, and rotates the winding drum by the frictional force.
Alternatively, a winding device may be used in which the film winding drum is driven and at the same time the surface of the film winding layer is driven or is wound while being brought into contact with a surface roll that is not driven.

A roll-shaped film wound body wound onto a winding drum by such a winding device is composed of a wound film made of synthetic resin and an air layer interposed between the wound layers of each film. The amount of air interposed between the wound film layers is controlled by the winding tension of the film or the pressing force of the surface roll against the surface of the film wound layer, and as the film winding tension and the pressing force of the surface roll increase, Air volume decreases.

Synthetic resin films, especially uniaxially stretched films that are stretched in either the vertical or horizontal directions, or biaxially stretched films that are stretched in both the vertical and horizontal directions, have a tendency to shrink after being stretched as an inherent characteristic. To illustrate, a film wound body wound into a roll on a winding drum undergoes a so-called tightening phenomenon in which the hardness of the entire wound body increases due to contraction of the wound film. Therefore, when winding a synthetic resin film, if the winding tension of the film or the pressing force of the surface roll is increased to reduce the amount of air caught between the winding layers of the film, the amount of air that is wound on the winding drum is reduced. A portion where thickness unevenness is accumulated in the width direction of the film becomes apparent. FIG. 1 shows a film F wound onto the winding drum 1 mounted on the winding shaft 2 in this manner. In this case, a band-shaped protrusion C is formed on the winding body R.
Due to the permanent strain inherent in synthetic resin films, the flatness and physical properties of the wound film in the vicinity of the protrusion C are significantly impaired. Furthermore, if the winding tension is increased when winding a thin synthetic resin film, vertical wrinkles are likely to occur in the wound film, further deteriorating the winding appearance of the film wound body. Conventionally, measures have been taken to improve this problem, such as buffering film tension fluctuations, improving film path parallelism, and increasing the rigidity of the winding drum, but these have not been satisfactory.

[Purpose of invention]

This invention was obtained as a result of studies to eliminate the above-mentioned drawbacks, and by blowing air between the conveying film and the surface roll, it is possible to improve the flatness of the film very efficiently without any change in quality on the film surface. It is an object of the present invention to provide a winding device that can prevent (projections).

[Structure and implementation examples of the invention]

The object of the present invention is to provide an air blowing device that blows air between the conveyed film and the surface roll before winding it into a roll in a device that winds up a synthetic resin film that is continuously conveyed and supplied into a roll. At the same time, the air nozzle of the device is oriented in the tangential direction of the surface roll and the film, and the distance from the tip of the nozzle to the point of contact of the tangential line is 30 to 60 mm.
This can be achieved by setting it to mm.

The present invention will be explained below with reference to the drawings.

FIG. 2 shows an embodiment of the winding device according to the present invention, in which F is a synthetic resin film transported by a transport roll 18, 15 is a cutter for cutting the synthetic resin film, and 21 is a cutter for cutting the synthetic resin film, and 21 is forced by a drive motor 20. The winding drum is being driven, R is a winding body, 22 is a winding arm, and 19 is a surface roll with which the winding body R is in contact. In addition, air is supplied to the stop valve 11 from an air source (not shown).
Air is supplied via conduit 13 and air chamber 14 . Air chamber 14 is provided to prevent fluctuations in air pressure and volume. Furthermore, as shown in FIG. 3, the supplied air passes through a flow rate control valve 16 and is blown out between the surface roll 19 and the conveying film F from an air nozzle 17. The amount and pressure of blown air are adjusted by the valve 16. 12 is a pressure gauge that displays air pressure. The air pressure of the air blowing device is preferably a medium pressure of 3 to 5 kg/cm ² , and the cross-sectional shape of the tip of the air nozzle 17 is preferably such that its longitudinal direction coincides with the width direction of the film. The air nozzle of the air blowing device should be oriented in the tangential direction of the surface roll and the film, and the distance from the tip of the nozzle to the contact point of the tangential line should be 30 to 60 mm. If this distance is less than 30 mm, uneven wind speed distribution will occur, resulting in uneven winding film surface.
On the other hand, if it exceeds 60 mm, the air flow from the nozzle is diffused and the parallelism (tangentiality) between the supplied film and the air flow is relaxed, so the chamfering effect of the wound film is reduced, and the effect of the present invention is exhibited. It will no longer be done.

[Effect of idea]

FIG. 4 is a perspective view showing the principle and effect of the present invention. By blowing air between the surface roll 19 and the film F, accompanying air currents are generated as shown by broken line arrows 23 toward both ends in the width direction of the film. do. The accompanying air current exerts an accompanying force on the film F toward both ends in the width direction of the film, and the film is wound with flatness. ) is significantly improved. Further, the winding device according to the present invention can be widely applied not only to synthetic resin films but also to winding devices for thin (3 to 50 μm) paper.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the winding body of the winding device, Fig. 2 is a perspective view of the winding device according to the present invention, Fig. 3 is a main sectional view of the air blowing device, and Fig. 4 is the air blowing device. It is a perspective view showing the principle and effect of. F... Synthetic resin film, 1... Winding drum, 2... Winding shaft, R... Winding body, C... Projection, 11... Stop valve, 12... Pressure gauge, 13... Conduit, 14 ...Air chamber, 1
5...Cutter, 16...Flow rate adjustment valve, 17
... Air nozzle, 18 ... Conveyance roll, 19 ...
Surface roll, 20... Drive motor, 21... Winding drum, 22... Winding arm.

Claims (1)

[Scope of utility model registration request] In a device for winding a synthetic resin film that is continuously conveyed and supplied into a roll, an air blowing device is installed to blow air between the conveyed film and the surface roll before winding it into a roll, and the device A winding device for a synthetic resin film, characterized in that the air nozzle is oriented in the tangential direction of the surface roll and the film, and the distance from the tip of the nozzle to the contact point of the tangential line is 30 to 60 mm.