JPH07276Y2 - Tubular film cooling system - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a cooling device for a tubular film in a water-cooled blown film forming apparatus.

[Conventional technology]

As is well known, the inflation molding method is one of the molding methods for a tubular film made of a thermoplastic, and the thermoplastic is extruded in a molten state from an annular slit die of a pressing machine, and a gas such as air is fed into the tube. This is a method of forming a tubular film by inflating the film to a predetermined diameter, cooling and solidifying the film with air, water, etc., and continuously taking it with a nip roll.

As the water cooling type cooling device in the inflation method, a tubular film extruded in a molten state from an annular slit die is disposed on the outer side (outer peripheral part) of the film and on the outer peripheral part of the water cooling ring. The cooled water is cooled and solidified by a cooling device composed of a cooling water tank containing the water, and wound on a winder via a nip roll.

[Problems to be solved by the device]

In the conventional device, when the film folding diameter is changed, the water cooling ring must be replaced with a predetermined diameter. For that purpose, it is necessary to stop the apparatus once and remove the tube extruded from the die, which has problems such as a decrease in productivity, an increase in loss of raw material resin, and complexity of water-cooling ring replacement work, It is industrially disadvantageous.

In consideration of the above problems of the prior art, the present inventor has made earnest studies to provide a water cooling ring that can be replaced without stopping the apparatus, and as a result, found that the problems can be solved by using a special structure for the water cooling ring, The present invention has been completed.

[Means for Solving the Problems]

The gist of the present invention is an apparatus for cooling a film extruded in a cylindrical shape, which accommodates an annular water cooling ring arranged outside the cylindrical film and water arranged on an outer peripheral portion of the water cooling ring. The cooling water tank is composed of a water-cooling ring, a tubular portion facing the tubular film, and a collar-shaped portion provided on the outer surface of the tubular portion.The water-cooling ring is separated in the radial direction of the tubular film. The cooling water tank is provided with an opening at the bottom having a diameter larger than that of the tubular portion of the water-cooling ring and smaller than that of the flange, and the flange of the water-cooling ring is formed on the opening. The present invention resides in a cooling device for a tubular film, characterized in that a water cooling ring is installed so as to be movable in a lateral direction by being placed.

Hereinafter, an example of the device of the present invention will be described in more detail with reference to the drawings.

FIG. 1 is an explanatory view showing an example of a water-cooled inflation device, and FIG. 2 is an exploded perspective view showing an example of a water-cooled ring.

In the figure, 1 is a cooling device, 2 is a water cooling ring, 3 is a cooling water tank, 4
Is an extruder, 5 is a die, 6 is a tubular film, 7 is a nip roll, 8 is a winder, 9 and 9'are ring bodies, 10 and 10 'are flanges, 11 is a protrusion, and 12 is a stopper. Shown respectively.

The thermoplastic synthetic resin melt-kneaded by the extruder 4 is a die 5
Is extruded as a tubular film 6. Air is blown into the extruded tubular film 6 to expand it to a predetermined diameter. The tubular film 6 having a predetermined diameter is cooled from the outside to be solidified, passes through a nip roll 7, and is wound by a winder 8
To be wound up.

In the present invention, the water cooling ring of the cooling device for cooling the above-mentioned tubular film 6 is separable as shown in FIG. The water cooling ring is composed of ring bodies 9 and 9'which are tubular portions facing the tubular film, and collar-shaped portions 10 and 10 'provided on the outer surface of the tubular portions (ring bodies).
The direction in which the water cooling ring separates (the direction in which it separates) is the radial direction of the tubular film. Normally, as shown in FIG. 2, a straight dividing line is provided in the vertical direction (direction parallel to the take-up direction of the tubular film) so that the ring bodies 9 and 9'can be separated from each other. May be inclined as long as the upper and lower sides of the ring body are connected to each other, and the ring body is not limited to the one divided into two as shown in the figure, and may have a shape that can be divided into three or more.

A protrusion is formed on the mating surface of the ring bodies 9 and 9'of the water cooling ring 2.
It is preferable in terms of alignment that 11 and a matching hole into which the protrusion 11 is fitted are provided so as to face each other. Also, the ring body 9, 9 '
It is also good to have a stopper plate 12 etc. to fix each other.

The collar-shaped portions 10 and 10 ′ provided on the ring bodies 9 and 9 ′ are for installing a water cooling ring on the cooling water tank 3. The bottom portion of the cooling water tank is provided with an opening having a diameter larger than that of the tubular portion of the water cooling ring and smaller than that of the collar portion. As shown in FIG. 1, the opening portion of the cooling water tank 3 is closed by the collar portion. Is placed as. The water cooling ring 2 can be moved laterally by the difference between the outer diameter of the tubular portion and the inner diameter of the opening of the cooling water tank.

Since the split type water cooling ring 2 of the present invention has the above-mentioned structure, when the film folding diameter is changed during the inflation molding, the air inside the tubular film 6 is removed during the operation of the molding apparatus. The water to the cooling water tank of the cooling device is stopped, and the stopper 12 of the water cooling ring is removed, the ring bodies 9 and 9'are separated and removed, and another water cooling ring of another desired diameter is attached. . At this time, since the water cooling ring can be moved laterally to some extent, installation of the water cooling ring is extremely easy.

[Effect of device]

By using the cooling device of the present invention, the water cooling ring can be replaced without stopping the extruder, so that the diameter can be changed by a simple operation when manufacturing films of various folding diameters.
It is a very suitable device for practical use.

[Brief description of drawings]

FIG. 1 is an explanatory view showing an example of a water-cooled inflation device, and FIG. 2 is an exploded perspective view showing an example of a water-cooled ring. In the figure, 1 is a cooling device, 2 is a water cooling ring, 3 is a cooling water tank, 4
Is an extruder, 5 is a die, 6 is a tubular film, 7 is a nip roll, 8 is a winder, 9 and 9'are ring bodies, 10 and 10 'are flanges, 11 is a protrusion, and 12 is a stopper. Shown respectively.

Claims (1)

[Scope of utility model registration request] 1. An apparatus for cooling a film extruded in a tubular shape, which accommodates an annular water cooling ring arranged outside the cylindrical film and water arranged on an outer peripheral portion of the water cooling ring. The cooling water tank is composed of a water-cooling ring, a tubular portion facing the tubular film, and a collar-shaped portion provided on the outer surface of the tubular portion.The water-cooling ring is separated in the radial direction of the tubular film. The cooling water tank is provided with an opening at the bottom having a diameter larger than that of the tubular portion of the water-cooling ring and smaller than that of the flange, and the flange of the water-cooling ring is formed on the opening. A cooling device for a tubular film, wherein a water cooling ring is installed so as to be movable in a lateral direction by being placed.