JPH07156928A - Method and device for shrinking heat-shrinkable flat tube - Google Patents

Abstract

PURPOSE:To prevent a tube from becoming loose to a container and idling, or prevent wrinkles, etc., from generating on the tube by effectively suppressing a container from swelling by being heated when the tube is shrunk by heating. CONSTITUTION:For a shrinking device for a heat-shrinkable flat tube, an opened flat heat-shrinkable tube 6 is fitted on the outside of a container 5, and the tube 6 is shrunk by heating. For such a shrinking device, the heating device consists of a first heating means 12 which shrinks the tube 6 being fitted on the outside of the container 5 by a specified amount, and a second heating means 25 to heat both folding lines which are formed on the tube 6 having been shrunk by the first heating means 12.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-shrinkable flat tube which is attached to a container or the like as a cap seal or a cylindrical label by opening a soft tube made of synthetic resin and folded flat. The present invention relates to a shrink method and an apparatus thereof.

[0002]

2. Description of the Related Art Conventionally, for example, a blow-molded container is generally equipped with a tubular heat-shrinkable label. As a means for mounting the label, first, a flat-shaped container is used. After opening the tube, the tube is externally fitted to the container and then heat-shrinked by a shrink device.

[0003]

Since the above-mentioned tube is normally stored in a flat state, folds with creases are formed at both ends of the tube when opened. Therefore, when the tube is attached, the entire tube is heated for a long time in order to eliminate this fold, and the entire container is heated and expanded together with the tube.

As a result, the tube is attached to the container in an expanded state, and when the temperature of the container immediately after the tube rises, the tube is in close contact with the container, but with time, the tube shrinks. Although there is almost no, the container cools and contracts, so there is a risk that the tube may loosen and run idle, or wrinkles and slack may partially occur. Particularly, for example, when the container is a bottle made of blow-molded polyethylene or polypropylene and the tube is a label made of heat-shrinkable polyester, there is a drawback that the above problem becomes remarkable due to the difference in expansion coefficient.

The present invention has been made in view of the above-mentioned problems of the prior art, and effectively prevents the container from being heated and expanded at the time of heat shrinking of the tube, so that the tube is loosened and idles. And to prevent wrinkles and the like from occurring in the tube.

[0006]

The present invention has been made as a method and apparatus for shrinking a flat tube in order to solve the above-mentioned problems. The feature of the flat tube shrinking apparatus is that it has an open flat shape. In the shrink device of the heat-shrinkable flat tube, in which the heat-shrinkable tube 6 is fitted onto the container 5 and heat-shrinks the tube 6, the heat-shrinkable device shrinks the tube 6 fitted onto the container 5. A first heating means (12) for shrinking a predetermined amount and the first heating means (12)
The second heating means 25 is for heating both folds 6a formed on the tube 6 contracted by the heating means 12.

The flat tube shrinking method is characterized in that an open flat heat-shrinkable tube 6 is fitted onto a container 5, and the tube 6 is fitted around the folds 6a formed at both ends thereof. This is to heat-shrink and leave it in close contact with the container 5, and then heat the periphery of the folds 6a to mount the tube 6 on the container 5.

Further, a feature of the heat-shrinkable flat tube as a shrink device is that the heat-shrinkable flat tube 6 fitted onto the container 5 has a shrink nozzle for ejecting hot air. A plurality of hot air adjusting plates 14 are swingably provided in the nozzle body 13 to which hot air is supplied, and the nozzle body 13 can be detachably attached to the side wall 11 of the shrink device body 10. It is to be provided in.

[0009]

In the present invention, first, the tube 6 fitted onto the container 5 is contracted by the first heating means 12 by a predetermined amount. At this time, the tube 6 is difficult to shrink and both folds
It suffices to contract the other part while the contraction of 6a is incomplete, and it is possible to effectively prevent the container 5 from being heated.

Furthermore, since the two folds 6a of the tube 6 incompletely contracted are concentrated and contracted by the second heating means 25, the container 5 is only partially heated. Therefore, the container 5 can suppress the expansion due to the temperature rise, as compared with the case where the entire container 5 is heated, and therefore the tube 6
Even if the container 5 is cooled after mounting, the amount of shrinkage is reduced, and the close contact state of the tube 6 can be improved.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 to 3, reference numeral 1 denotes a shrink device, which conveys a large number of containers 5 (for example, polyethylene bottles formed by blow molding) at intervals in the arrow direction by a belt conveyor 3 and The tube 6 is heat-shrinked as a label fitted over the tube.

The tube 6 is formed by forming a synthetic resin film made of a heat-shrinkable film such as polyester into a tubular shape, and then winding it into a roll, and then cutting it into a predetermined length while unwinding it. The container 5 is opened by an opening device (not shown) and fitted onto the container 5. The tube 6 fitted on the container 5 has two folds 6a with a crease.
However, it faces both sides with respect to the transfer direction.

The shrink device 1 has a first contraction zone A and a second contraction zone B from the upstream side in the transfer direction of the container 5. The first contraction zone A is a heating means for preheating that heats the tube 6 from the upstream side until just before contraction starts.
A first heating means 12 including a heating means 9b for shrinking the heated tube 6 is provided. The preheating heating means 9a and the contraction heating means 9b are provided with a plurality of hot air adjusting nozzle bodies 8 (shrinking nozzle bodies) arranged on both sides of the container 5 in order to eject hot air toward the tube 6.

Each hot air adjusting nozzle body 8 is constructed as a unit and is detachably attached to the side wall 11 of the apparatus body 10. As shown in FIGS. 4 to 6, each hot-air adjusting nozzle body 8 has a plurality of hot-air adjusting plates 14 swingably provided in a rectangular main body 13 having an open front surface. That is, the base of each hot-air adjusting plate 14 is pivotally supported by the upper wall 16 and the lower wall 18 via the pivotal support 20, and the upper wall 16 of the main body 13 has a notch length corresponding to the number of adjusting plates 14. The hole 17 is formed in an arc shape around the pivotal support portion 20 of each adjustment plate 14.

A guide pin 22 projecting from the upper end of each adjusting plate 14 is inserted into each notched slot 17, so that each adjusting plate 14 has a notch slot 17 centered on the pivot 20. It is possible to swing within the range of, and it is possible to adjust the distance between the adjusting plates 14 facing each other.

An opening 24 for taking in hot air is formed in the rear wall 26 of the main body 13 between the adjusting plates 14 facing each other. Therefore, hot air sent from a hot air supply device (not shown) is supplied into the main body 13 through the opening 24, and the facing adjustment plate 14 is faced.
The amount of hot air blown out onto the tube 6 can be adjusted by adjusting the interval of, and the blowing direction of hot air can be adjusted by the swing angle of the adjusting plate 14.

A mounting piece 27 is provided on the upper wall 16 of the main body 13 so as to project upward, and a locking opening 29 as a locked means is formed at the upper end of the mounting piece 27. A hook 30 as a locking means fixed to the side wall 11 of the apparatus body 10 is detachably hooked via each locking opening 29. Further, a fixed body 33 is rotatably provided on the lower wall 18 via a bracket 32, and a tip end of the fixed body 33 is the device main body.
It is installed in 10 freely.

The size and shape of the nozzle body 8 are appropriately determined so that the hot air can be jetted over the entire surface of the tube 6 mounted in the container 5, and the hot air of a size corresponding to each tube 6 can be adjusted. The nozzle body 8 can be attached to the side wall 11.

In the second contraction zone B, the infrared heaters 25 are arranged on both sides of the container 5, and the infrared heaters are provided.
The radiant heat from 25 allows the folds 7 on both sides of the tube 6 to be partially concentrated and heated.

The embodiment of the present invention has the above construction, and then the tube 6 is placed in the container 5 by using the apparatus having the above construction.
The case of mounting on the will be described. The container 5 is shown in FIG.
As shown in (1), the tube 6 is transferred by the belt conveyer 3 in an externally fitted state and reaches the first contraction zone A.
In the first contraction zone A, the tube 6 is first heated by the preheating heating means 9a to a temperature of about the temperature immediately before the start of contraction. For example, when the shrinking temperature of the tube 6 is 60 ° C, the tube 6 is heated to about 60 ° C.

During this heating, hot air is ejected from the hot air adjusting nozzle bodies 8 on both sides. By adjusting the interval between the adjusting plates 14, the jetting output and amount of the hot air can be adjusted and the adjusting plate 14 can be shaken. The direction of the hot air can be arbitrarily set depending on the moving direction, the hot air can be jetted uniformly over the entire tube 6 transferred together with the container 5, and the amount and temperature of the hot air supplied to each hot air adjusting nozzle body 8 are It is controlled by a controller (not shown).

Further, the hot air controlled nozzle 8 of the heating means for contraction 9b ejects the hot air controlled by the control device, so that the tube 6 is further heated and contracted. As shown in FIG. 8, immediately after the hot air is jetted, the tube 6 contracts sharply, but the temperature of the container 5 rises substantially linearly. Therefore, at the beginning of heating, the tube 6 with respect to the diameter of the container 5
The diameter ratio (label margin ratio) S sharply decreases. For example, when the label margin ratio reaches 0.5% as shown in FIG. 7B, the tube 6 is left around the area including both folds 6a. In the second step of the next step, in a state in which the container 5 is contracted to such an extent that it is in close contact with it.
The container 5 is transferred to the contraction zone B.

In the second contraction zone B, infrared rays are partially irradiated around the both folds 6a, so that both folds 6a are heated and shrunk.
As shown in (c), the container 5 will be closely attached. Although the container 5 is also heated by the infrared rays, since the heating is a part, it is possible to effectively suppress the expansion due to the temperature rise of the container 5 as compared with the case of heating the entire tube 6. .

Therefore, after the tube 6 is attached to the container 5, the container 5 shrinks little due to cooling, so that the close contact of the tube 6 to the container 5 can be made good and wrinkles and slack can be prevented. You can

The present invention is not limited to the above embodiment. For example, in the above embodiment, the first heating means 12 is composed of the preheating heating means 9a and the contraction heating means 9b.
The first heating means 12 does not need to have a separate heating device as described above, but may be a single heating device.

Further, the container may be other than a bottle such as polyethylene made by blow molding, and the point is that it is used for a container which is thermally expanded when the tube 6 is heated and contracted, such as a container made of other various synthetic resins. It is possible.

Moreover, the heating conditions of the tube 6 in the first shrinking zone A and the second shrinking zone B are appropriately set in consideration of the expansion rate depending on the material of the container 5 and the tube 6, and the heating temperature in each zone and The transfer speed of the container 5 is controlled by the controller.

[0028]

As described above, in the tube shrinking device of the present invention, the heating device forms the first heating means for shrinking the tube fitted on the container and the tube shrunk by the first heating means. Since it is composed of the second heating means for heating both of the folded portions, the first heating means first shrinks the tube by a predetermined amount while suppressing the temperature rise of the container,
Further, the second heating means allows both folds which require a relatively long heating time to be partially concentrated and heated to shrink, and the entire tube is heated until both folds are completely contracted as in the conventional case. The expansion of the container can be reduced as compared with the case where it is done.

As a result, even if the container is a label made of polyethylene or polypropylene and the tube is made of a heat-shrinkable polyester film, the amount of shrinkage of the container is reduced, and the label is loosened and rotated carelessly. It is possible to prevent the occurrence of wrinkles and the like on the label.

Further, according to the present invention, a plurality of hot air adjusting plates are swingably provided in a nozzle body main body to which hot air is supplied,
Moreover, since the nozzle body is detachably attached to the side wall of the shrink device body, the nozzle body can be easily and quickly attached to and detached from the shrink device, and a tube according to the size of each tube can be used. Becomes

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a front view of the shrink device.

FIG. 3 is a partial sectional side view showing a contracted state of the tube.

FIG. 4 shows a shrink nozzle body according to the present invention.
Is a cross-sectional plan view, and (B) is a cross-sectional side view.

FIG. 5 is a front view of the shrink nozzle body.

FIG. 6 is a rear view of the shrink nozzle body.

FIG. 7 shows a shrinking process of a tube, (a) is a cross-sectional plan view of the tube fitted onto the container, (b) is a cross-sectional plan view of the tube heated by the first heating means, and 4) is a cross-sectional plan view of the tube heated by the second heating means.

FIG. 8 is a graph showing the relationship between the container and the tube during heating.

[Explanation of symbols]

5 ... Container, 6 ... Tube, 6a ... Fold, 12 ... First heating means, 13 ... Nozzle body, 14 ... Hot air adjusting plate, 29 ... Locked part, 30 ... Locking part

Claims (4)

[Claims] 1. A shrinkable device for a heat-shrinkable flat tube, comprising an open flat heat-shrinkable tube (6) fitted on a container (5) and provided with a heating device for heating and shrinking the tube (6). In the heating device, the container (5)
A first heating means (12) for shrinking the tube (6) fitted to the outside by a predetermined amount, and both folds (6a) formed on the tube (6) contracted by the first heating means (12). A shrink device for a heat-shrinkable flat tube, comprising a second heating means (25) for heating. 2. An open flat heat-shrinkable tube (6) is fitted onto a container (5), leaving the tube (6) around the folds (6a) formed at both ends thereof. After shrinking by heating and closely contacting with the container (5), the periphery of the both folds (6a) is further heated to put the tube (6) into the container (5).
A method for shrinking a heat-shrinkable flat tube, characterized by being attached to 3. The shrinking method for a heat-shrinkable flat tube according to claim 2, wherein the periphery of both folds (6a) is heated by radiant heat of infrared rays. 4. A heat-shrinkable flat tube shrink device having a shrink nozzle for ejecting hot air to a flat tube (6) fitted onto a container (5), to which hot air is supplied. A plurality of hot air adjusting plates (14) are swingably provided in the nozzle body (13), and the nozzle body (13) is attached to and detached from the side wall (11) of the shrink device body (10). A heat-shrinkable flat tube shrink device, which is provided so as to be freely attached.