JPH0210010B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pallet shrink packaging method, and in particular to an improved pallet shrink packaging method that prevents horizontal displacement of the packaged items and pallets due to horizontal impact during transportation and reduces packaging costs. Regarding packaging methods.

Conventional pallet shrink packaging uses a heat-shrinkable film made by uniaxially or biaxially stretching thermoplastic resin raw materials such as polyethylene, polypropylene, and vinyl chloride to wrap the packaged items loaded on a pallet. The pallet and the item to be packaged were integrated by covering the pallet and heating it to shrink it. That is, the first
The figure is a perspective view showing a specific example of a pallet shrink packaging method using a conventional gusset bag.
It is a sectional view taken along the line A-A' in Figure 1, where 1 is a pallet, and 2 is a sectional view taken along the line A-A'.
3 indicates a packaged object, and 3 indicates a heat-shrinkable film. By wrapping the heat-shrinkable film 3 around the packaged items 2 stacked on the pallet 1 and heating it with an appropriate heating device, the heat-shrinkable film 3 shrinks and the packaged items 2 and pallet 1 are wrapped. are simultaneously tightened and packaged together.

However, for example, when the articles 2 to be packaged, such as sheet paper, are piled up on the pallet 1, the pallet is shrink-wrapped by the method described above, and then transported by a freight car, etc., the upper part of the sheet paper may simply be damaged due to longitudinal impact during transportation. Rather than shifting, the stacked sheets of paper, that is, the entire packaged material 2 slides on the pallet 1, as shown in Fig. 3 (Fig. 2).
This is a cross-sectional view showing the sliding state of the packaged items in the figure, and the numbers 1, 2, and 3 have the same meanings as in Figures 1 and 2 above. There are many accidents in which shipped base paper is damaged to the point that it can no longer be used, and to prevent this, the thickness of heat-shrinkable film is currently increased.

The present invention has been made in view of the current situation, and its purpose is to solve the problems of the conventional method, prevent lateral shifting due to sliding of the packaged items on the pallet, and reduce packaging costs. An object of the present invention is to provide a packaging method.

To summarize the present invention, the pallet shrink-wrapping method of the present invention includes a reinforcing band made of a thermoplastic resin film that spans both the lower side surface of the objects to be packaged loaded on the pallet and the side surface of the pallet, and extends below the lower end of the pallet. The method is characterized in that the heat-shrinkable film is wrapped around the outer surface of the pallet and the object to be packaged so as to project downward from the lower end of the pallet, and then the heat-shrinkable film is shrunk by heating. It is something.

According to the present invention, in the vicinity of the contact surface between the packaged object and the pallet, a reinforcing band is wrapped around the side surfaces of both, and a heat-shrinkable film is wrapped thereon to reinforce the interface between the two. Accidents can be prevented, the overall thickness of the heat-shrinkable film can be reduced, and packaging costs can be reduced.

As the thermoplastic resin film as the reinforcing band in the present invention, known films made of, for example, polyethylene, polypropylene, polyvinyl chloride, etc. can be used as appropriate.

In the present invention, in order to increase the strength of the package, it is desirable to fuse the thermoplastic resin film and the heat-shrinkable film by heating.
The heat-shrinkable film is heated to a temperature above its softening point by a known heating device for pallet shrink packaging and shrinks. At that time, the heat of the heat-shrinkable film is transferred to the thermoplastic resin film that is the reinforcing band. This is softened and the two are fused together. Therefore, in order to facilitate this fusion, it is appropriate to select a reinforcing band made of thermoplastic resin film whose softening point is the same as or lower than that of the heat-shrinkable film. It is also desirable to make the reinforcing band thinner. From this point of view (improving fusion bonding), it is desirable to use the same type of film for both films.For example, as a heat-shrinkable film, a low-density polyethylene film with a thickness of about 100 to 200μ (softening point of about 85 to 90℃) is used. ) and a low-density polyethylene film with a thickness of approximately 50 to 100μ (softening point approximately 80 to 90) as a thermoplastic resin film (reinforcement band).
℃) is preferably used in combination.

Generally, in pallet shrink packaging, the heat shrink film is placed approximately 100 to 200 times below the bottom edge of the pallet.
The heat-shrinkable film is made to protrude by approximately 1.0 mm, and is wrapped around the bottom surface of the pallet by shrinking the heat-shrinkable film. When used, use a thermoplastic resin film (reinforcement band) that is stretched more in the circumferential direction than in the vertical direction of the packaged object, that is, the thermoplastic resin film (reinforcement band), so that the heat-shrinkable film can be stretched to the lower surface of the pallet. Coiling can be promoted.

The pallet shrink-wrapping method of the present invention can be applied to not only the above-mentioned wrapping method using a gusset bag, but also the commonly used vertical wrap method and wrap-round method using a gusset tube. (See Examples below).

According to the present invention, (a) the thickness of the film increases near the contact surface between the packaged item and the pallet;
This not only effectively prevents accidents such as objects to be packaged sliding on the top surface of the pallet and protruding from the pallet during horizontal impact during transportation, but also reduces the thickness of the heat-shrinkable film and improves packaging. (b) Since the heat-shrinkable film heated above its softening point fuses with the reinforcing band before it starts shrinking, vertical shrinkage stress is applied afterwards. However, the bottom edge of the heat-shrinkable film is not pulled up above the bottom edge of the pallet.
This provides good wrapping around the underside of the pallet.

Next, embodiments of the present invention will be described in detail with reference to the drawings, but the present invention is not limited thereto.

Example 1 (Wrapping method using a gusset bag) Figure 4 is a sectional view showing a specific example of the present invention.
A shows the state before contraction, b shows the state after contraction, and FIG. 5 is a partially enlarged view of the reinforcing band insertion part, a shows the state before contraction, and b shows the state after contraction. Also, in the figure, 1 is a pallet, 2 is a packaged object, 3 is a heat-shrinkable film, 4 is a reinforcing band, and 5 is a
indicates the fused surface of the heat-shrinkable film 3 and the reinforcing band 4.

A reinforcing band 4 made of a low-density polyethylene film (softening point: about 85°C) with a thickness of about 80 μm is placed across both about 200 mm of the lower side surface of the packaged object 2 and the side surface of the pallet 1, and extends about 200 mm below the lower end of the pallet 1. 100mm
It was wrapped so that it protruded and fixed with tape or other suitable means. Next, low-density polyethylene (softening point: about 90°C) with a thickness of about 120 μ and a length sufficient to protrude about 200 mm below the lower end of pallet 1 is used.
A heat-shrinkable film 3 in the form of a gusset bag was placed over the article to be packaged 2, and the heat-shrinkable film 3 was heated above its softening point to shrink using a known heating device for pallet shrink packaging. At this time, the heat of the heat-shrinkable film 3 was transferred to the reinforcing band 4 and softened it, and both films were fused at the fused surface 5.

In addition, the lower end of the heat-shrinkable film 3 is
As shown in FIG. 2, there is no difference from conventional pallet shrink wrapping in that the wrapping material is wrapped around the lower surface of the pallet 1 and the article to be packaged 2 is fixed on top of the pallet 1.

Example 2 (Vertical design using gusset tubes)
Wrapping Method) FIG. 6 is a perspective view showing another embodiment of the present invention, in which a shows a reinforcing band wrapping step b shows a tubular heat-shrinkable film wrapping step, and c shows a completed state of packaging. In addition, 1 in the figure is a pallet, 2 is a packaged item, and 3 is a pallet.
4 is a heat-shrinkable film, 4 is a reinforcing band, and 6 is a rotary table.

The materials used for the pallet 1, the packaged object 2, the heat-shrinkable film 3, and the reinforcing band 4 used in this example were the same as those in Example 1.

First, in step a, while rotating the packaged item 2 on the rotary table 6, the reinforcing band 4 wound into a roll is pulled out and stretched across both the lower side surface of the packaged item 2 and the side surface of the pallet 1. , and wrap it around the pallet 1 so that it protrudes from the lower end of the pallet 1, and after the object to be packaged 2 has rotated approximately once, this is stopped, and the end of the wrapping of the reinforcing band 4 is cut, and the reinforcing band 4 is wrapped by a known method such as heat sealing. Fixed.

Next, the pallet 1 and the packaged items 2 integrated by the reinforcing band 4 are transferred to a suitable conveyor (not shown).
etc., move to step b, and use a known vertical wrap type automatic packaging machine to wrap the gusset tube-shaped heat-shrinkable film 3 into pallet 1.
It was covered so that it protruded from the lower end. The package thus wrapped was further moved by a conveyor or the like, and sent to the next heating shrinkage step (not shown) in state c. Note that this step is the same as in Example 1, so the explanation is omitted.

Embodiment 3 (Wrap-round method) Fig. 7 is a perspective view showing another specific example of the present invention, in which a shows a structure in which a packaged object moving on a conveyor is wrapped around a reinforcing band and a heat-shrinkable film sheet. A step in which the front surface is covered, b is a step in which the side surface is covered, c is a step in which the rear surface is covered,
d indicates the completed state of packaging. In the figure, 1 is a pallet, 2 is a packaged object, 3 is a heat-shrinkable film, and 4 is a pallet.
7 indicates a reinforcing band, and 7 indicates a melt-cut seal bar.

This device is a known wrap-round type automatic packaging machine, and the present invention was applied to this device. Note that the above palette 1 used in this example,
The materials of the packaged object 2, the heat-shrinkable film 3, and the reinforcing band 4 were also the same as those in Example 1.

First, in step a, the packaged object 2 that has moved on the conveyor comes into contact with the reinforcing band 4 and the heat-shrinkable film 3 unwound from the unwinding roll, and the front surface thereof is covered by both, and in step b, Similarly, both sides covered the sides. In step c, the packaged object 2 that has further advanced on the conveyor is covered with the two films on its rear surface by the fusing seal bar 7, and is fused and cut in the longitudinal direction, and is packaged in the form shown in d. Ru. The package thus wrapped was heated in the next step (not shown), and a heat-shrinkable film was wrapped around the upper surface of the object to be packaged 2 and a portion of the lower surface of the pallet 1.

As explained above, according to the present invention, it is possible to prevent the objects to be packaged from sliding on the pallet and to package them safely using a relatively thin heat-shrinkable film, thereby reducing packaging costs. can.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing a specific example of a pallet shrink packaging method using a conventional gusset bag, Fig. 2 is a sectional view taken along line A-A' in Fig. Sectional view showing the sliding state of the package, No. 4
5 is a partially enlarged view of the reinforcing band insertion part in FIG. 4, and FIG. FIG. 7 is a perspective view showing another specific example (Example 3) of the present invention. DESCRIPTION OF SYMBOLS 1... Pallet, 2... Item to be packaged, 3... Heat-shrinkable film, 4... Reinforcement band, 5... Fusion surface of heat-shrinkable film 3 and reinforcing band 4, 6... Rotary table, 7 ...Fused seal bar.

Claims (1)

[Scope of Claims] 1. A reinforcing band made of a thermoplastic resin film is wrapped around both the lower side of the packaged items loaded on the pallet and the side of the pallet so as to protrude downward from the lower end of the pallet, and Wrapping the object to be packaged and the outer surface of the pallet with a shrinkable film so as to protrude downward from the lower end of the pallet,
1. A pallet shrink packaging method, characterized in that the heat-shrinkable film is then shrunk by heating. 2. Claim 1, in which a heat-shrinkable film and a reinforcing band made of a thermoplastic resin film are fused together.
Pallet shrink wrapping method described in Section 1. 3. The pallet shrink packaging method according to claim 1 or 2, wherein the reinforcing band made of a thermoplastic resin film has a softening point lower than that of the heat-shrinkable film.