JPH09175535A - Synthetic resin pallet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent sliding between a pallet and a load on the pallet or between pallets, by integrally arranging a plurality of protruded lines made of the same material on both surfaces of the top face and the rear face and specifying the opening ratio of the top plate and the bottom plate. SOLUTION: Thus flat pallet 1 made of a thermoplastic resin is provided with two-directional insertion parts and shaped to have a flat and nearly rectangular parallelepiped form with the top plate 2, the bottom plate 3, the breadthwise side plates 4, 4, and side plates 5, 5 in the depth. Both top plate and bottom plate are applicable. Insertion openings 6, 6 in which forks of a forklift or the like used for transferring the pallet 1 can be inserted, are provided at specified positions of the breadthwise side plates 4, 4. A plurality of protruded lines 7 are integrally formed in both parallel and right-angled directions against the insertion direction of forks, on the top plate 2 and the bottom plate 3. The opening ratio of the top plate or the top plate and the bottom plate of the pallet is 20% or smaller respectively. Accordingly, the protruded lines can be arbitrarily arranged at necessary parts to improve the slipping troubles between the pallet and the load.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a top plate or a synthetic resin pallet in which convex strips are integrally arranged on the surfaces of the top plate and the bottom plate.

[0002]

2. Description of the Related Art Generally, pallets are used for transporting and storing articles, and wooden pallets have been widely used. In recent years, however, pallets are made of synthetic resin for weight reduction. I'm getting more and more. However, since the synthetic resin is highly slippery, there is a disadvantage that the articles loaded on the synthetic resin pallets are slippery and the pallets stacked are slippery. Therefore,
In order to prevent the slipping of the transported object, a large number of materials having a friction coefficient larger than that of the molding material of the pallet, for example, a non-slip member such as rubber embedded, fitted or covered in the pallet have been proposed. 62-6502, JP-B-63-44625, JP-A-4-57744 and JP-A-5-42943). However, the above-mentioned ones have a problem that a slip preventing member made of a material different from that of the pallet body is required and a separate step is required for attaching the slip preventing member, resulting in an increase in cost.
Further, for slippage between pallets, the slip prevention member alone is insufficient.

Further, in a synthetic resin pallet having a top plate and a bottom plate having an opening ratio of about 50% and constituted by a U-shaped rib connecting the top plate and the bottom plate, for example, in the vicinity of the outer peripheral edge of the loading surface. In some cases, a plurality of ridges having a length of about 55 mm, a width of about 5 mm, and a height of about 0.8 mm are integrally provided with the pallet body over the entire circumference. Although this pallet has good pallet-to-pallet slip prevention, it has the disadvantage that it slips depending on the load because the ridges are arranged around the entire outer peripheral edge. Also, the pallet is
Since the top plate and the bottom plate have an aperture ratio of about 50%, there is a disadvantage that there are restrictions on the places where the ridges are arranged.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above problems and to provide a synthetic resin pallet which can prevent slipping between the pallet and the load and between the pallet and the pallet.

[0005]

In view of such circumstances, the inventors of the present invention have diligently studied slippage occurring in a synthetic resin pallet, and as a result, a top plate having an aperture ratio of 20% or less, or
It was found that slippage between a pallet and a load and between a pallet and a pallet can be prevented by disposing a ridge made of the same material as that of the pallet on a synthetic resin pallet having a top plate and a bottom plate, thus completing the present invention. Let

That is, the present invention is made of a resin or a material including a filler therein, is provided with a top plate and a bottom plate, and is provided with a large number of ribs so as to connect the top plate and the bottom plate. A synthetic resin pallet in which a fork is inserted in a part of the rib,
A plurality of ridges made of the same material as the material forming the top plate or the top plate and the bottom plate are integrally provided on the surface of the top plate or the top plate and the bottom plate, and the ridges are arranged. The present invention provides a pallet made of synthetic resin, characterized in that the opening ratio of the top plate or the top plate and the bottom plate is 20% or less. Hereinafter, the present invention will be described in detail.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION A synthetic resin pallet (hereinafter abbreviated as a pallet) of the present invention is made of resin or a material containing filler therein, and has a top plate and a bottom plate. The pallet is provided with a large number of ribs so as to be connected to each other, and an insertion port into which a fork is inserted is provided in a part of the ribs. In addition, the top plate of the pallet, or the top plate and the bottom plate, each have an aperture ratio of 20.
% Or less, preferably 0%. The opening ratio is the ratio of the total area of the holes or recesses formed in the top plate or the bottom plate to the total area of the top plate or the bottom plate. An opening ratio of 0% means that the top plate or the bottom plate has no holes or recesses at all, and refers to a pallet having a smooth surface on the top plate or the bottom plate. The pallet is formed by stacking two pallet plates of the same size so as to face each other and joining the facing surfaces of both.
In addition, a large number of plate-shaped ribs are formed inside the pallet so as to connect the top plate and the bottom plate.

Examples of the synthetic resin include thermoplastic resins, and examples thereof include polyethylene resin, polypropylene resin, polyamide, polyethylene terephthalate, acrylonitrile-butadiene-styrene copolymer (AB).
S), polyvinyl chloride resin, polycarbonate, etc. are used. In addition, modified products and mixtures of these thermoplastic resins,
Alternatively, a polymer alloy or the like can be used. Further, a filler such as glass fiber or carbon fiber may be blended with these thermoplastic resins as needed. Also,
Additives such as an antioxidant, an ultraviolet ray inhibitor, a coloring agent, a release agent, and a low shrinkage agent may be added as necessary.

The above-mentioned thermoplastic resins are, for example, price, affinity with fillers and additives, ease of molding, use and size of pallet, mechanical strength required for pallet (for example,
It may be appropriately selected according to the compressive strength, bending strength, flexural strength, etc.) and various physical properties. Among the above-exemplified thermoplastic resins, a polypropylene resin such as a propylene homopolymer or a copolymer of propylene and another monomer is particularly preferable from the viewpoint of mechanical strength required for a pallet.

The above thermoplastic resin may be used in a non-foamed state, and in order to improve its fluidity and the like,
You may use it in the state foamed about 1.1 to 1.2 times. When the thermoplastic resin is such a foam, molding can be performed similarly to a non-foam, and further weight reduction of the pallet can be realized.

The above-mentioned filler is blended in order to further improve the mechanical strength of the pallet. The filler has stability to withstand the melting point of the thermoplastic resin, and, it is necessary that the affinity with the thermoplastic resin is good, for example, inorganic fibers such as glass fibers and carbon fibers, Inorganic powders such as talc, clay, silica and calcium carbonate are used.

The above-mentioned filler may be appropriately selected according to, for example, price, affinity with a thermoplastic resin, use and size of pallet, mechanical strength required for pallet, various physical properties, and the like. Among the above-mentioned fillers, inorganic fibers, particularly glass fibers, are preferable in terms of price and mechanical strength required for pallets.

The fiber length of the above-mentioned inorganic fibers depends on the kind of fibers to be mixed, but is preferably 0.1 mm to 50 m.
m, more preferably 1 mm to 15 mm. Although the fiber diameter of the inorganic fiber depends on the type of the fiber to be compounded, it is 1
μm to 50 μm are preferred. The particle size and shape of the inorganic powder are not particularly limited. The blending amount of the filler with respect to the above thermoplastic resin depends on the type of the filler to be blended, but from the viewpoint of mechanical strength required for the pallet,
Preferably not more than 50% by weight, more preferably 10% by weight
-40% by weight, more preferably 15-35% by weight. Further, each of the above-mentioned fillers may be blended into the thermoplastic resin alone, or if necessary, two or more types may be blended into the thermoplastic resin. Furthermore, the method of mixing the thermoplastic resin and the filler is not particularly limited.

The pallet of the present invention has a top plate surface or
By disposing a plurality of ridges on both surfaces of the top plate and the bottom plate, the load can be engaged with the ridge, and slip between the pallet and the load can be prevented. The load is like a resin bag,
If it transforms itself, its effect will increase. Further, when a plurality of pallets of the same kind are stacked, the convex stripes of the top plate and the bottom plate are engaged with each other to restrain the movement of the pallets and prevent the pallets from sliding. Furthermore, since the ridges are made of the same material as the top plate or the same material that forms the top plate and the bottom plate and are integrally formed with these top plates, etc., it is possible to provide a pallet with anti-slip properties at a low cost. it can.

The height of the ridge is, for example, 0.8 mm to 5 mm.
It is about 1 mm to 2 mm. The width, interval and length of the ridges are not particularly limited and may be appropriately selected depending on the articles to be loaded. For example, the width is about 0.5 mm to 20 mm, preferably 1.5 mm.
~ 3 mm, with a spacing of about 1 cm to 30 c
m, preferably 5 cm to 10 cm, and the length is approximately 5 cm to the width of the pallet or the depth of the pallet, preferably 20 cm to 1 of the width of the pallet.
/ 2 or less.

In the pallet of the present invention, the above-mentioned convex strips may be arranged in a direction parallel and / or orthogonal to the fork insertion direction. Such a pallet can effectively prevent slipping of a load due to bending of the pallet when carrying a load by a fork.

In the pallet of the present invention, the convex strips may not be present on the center line of the top plate or the bottom plate, but may be arranged asymmetrically with the center line of the top plate or the bottom plate sandwiched therebetween. Since it is possible to prevent the ridges from overlapping each other when stacking such pallets, it is easy to stack the pallets with the end portions of the pallets aligned.

In the pallet of the present invention, the ridges may be provided on the top plate or the entire top plate and bottom plate. The provision of the ridges on the top plate or the entire surface of the top plate and the bottom plate means, for example, a pallet as shown in FIG. FIG.
FIG. 4 is a top view showing an example of the pallet of the present invention in which the ridges are arranged on the top plate or the entire surface of the top plate and the bottom plate.

FIG. 1 is a (a) top view, (b) front view, and (c) side view of a pallet according to an embodiment of the present invention. As shown in FIG. 1, the pallet 1 is a two-way flat pallet and is made of a thermoplastic resin. Pallet 1 is
It has a flat and substantially rectangular parallelepiped shape including the top plate 2 and the bottom plate 3, the width direction side plates 4 and 4, and the depth direction side plates 5 and 5, and both the top plate 2 and the bottom plate 3 can be used. There is.

At predetermined positions of the width direction side plates 4 and 4, insertion ports 6 and 6 into which forks (not shown) such as a forklift truck used when moving the pallet 1 are inserted are provided. There is. The above-mentioned insertion ports 6 and 6 are provided in parallel from one widthwise side plate 4 toward the other widthwise side plate 4, that is, so as to penetrate the main body of the pallet 1. A plurality of ridges 7 are integrally provided on the top plate 2 and the bottom plate 3 in the direction parallel to and perpendicular to the fork insertion direction. Moreover, the A section enlarged view which expanded the ridge 7 in FIG. 1 is shown. The ridge 7 is tapered so that it can be easily removed from the mold.

The above-mentioned ridges are not arranged on the center lines 8 passing through the surfaces of the top plate 2 and the bottom plate 3, but are arranged asymmetrically with the center lines interposed therebetween. The ridge arrangement on the bottom plate 3 is the same as the ridge arrangement on the top plate 2, or the arrangement of the top plate 2 is rotated by 180 degrees.

In the pallet of the present invention, a slip preventing member made of a material having a coefficient of friction larger than that of the material forming the top plate or the bottom plate is attached between the convex stripes to further prevent the slip. Can be increased. Examples of the material having a large friction coefficient include rubber, ethylene-vinyl acetate copolymer, and thermoplastic elastomer. Further, the above-mentioned anti-slip member may be arranged in a strip shape, a string shape, a grommet, or the like continuously or discontinuously. Further, by appropriately selecting the positions and intervals of the ridges, the ridges can be used for positioning the anti-slip member. Further, since the anti-slip member is arranged between the ridges, there is no risk of the anti-slip member peeling off or falling off even when the load is caught on the anti-slip member. FIG. 2 is a top view showing an example of the pallet of the present invention in which the slip prevention member 9 is attached between the ridges.

The method of manufacturing the pallet of the present invention is not particularly limited except that a mold provided with a concave groove is used, and for example, a usual method such as injection molding, injection compression molding, injection press molding or the like is used. A molding method may be mentioned. Examples of the method of disposing the anti-slip member include a method of post-bonding the anti-slip member to a pallet, a method of previously disposing the anti-slip member in a mold during pallet molding, and the like.

[0024]

Hereinafter, the present invention will be described based on examples.
The present invention is not limited to these examples. Next, the evaluation methods performed in Examples and Comparative Examples will be shown. (1) Sliding test of load As shown in FIG. 3, a 25 kg resin bag was loaded on a pallet. The pallet was set in a mold reversing machine, and the state where the resin bag started to slide by tilting the mold reversing machine up to 45 degrees was evaluated as follows. ◎ ... very slippery. ○: Slippery. Δ: Slightly slips. X: Very slippery. (2) Sliding test between pallets As shown in FIG. 4, pallets were stacked. The pallet was set in a mold reversing machine, and the state where the upper pallet started to slide by tilting the mold reversing machine up to 45 degrees was evaluated as follows. ◎ ... very slippery. ○: Slippery. Δ: Slightly slips. X: Very slippery. (3) Productivity ⊙ ... Manufacturing is very easy and manufacturing cost is also low. ◯ ... Easy to manufacture and inexpensive. Δ: The production is rather complicated and the production cost is high.

Example 1 Using a polypropylene resin as a synthetic resin, a pallet as shown in FIG. 1 was manufactured by an injection press molding method. The aperture ratios of the top plate and the bottom plate were 0% each. The size of the pallet is 1100 mm wide and 1100 m deep.
m, height 144 mm, top plate 3 mm, and bottom plate 3 mm. A plurality of ridges were integrally arranged on both surfaces of the top plate and the bottom plate in parallel with and in a direction orthogonal to the fork insertion direction. The height of the ridge is 1 mm, the width is 2 mm, and the distance between the ridges provided parallel to the fork insertion direction is 8 cm.
The interval between the ridges provided in the direction orthogonal to the fork insertion direction was 5 cm. The length of the ridges provided in parallel with the fork insertion direction was 40 cm, and the length of the ridges provided in the direction orthogonal to the fork insertion direction was 50 cm. Table 1 shows the evaluation results.

Example 2 A pallet as shown in FIG. 2 was manufactured by the injection press molding method. The material and size of the pallet were the same as in Example 1. A ridge was formed on both the top plate and the bottom plate. Also,
A band-shaped slip preventing member made of a thermoplastic elastomer (TPE) sheet was stuck between the ridges. The TPE sheet had a thickness of 2 mm and a width of 25 mm. The distance between the ridges was 8 cm, but the distance was adjusted to the width of the band-shaped anti-slip member only at the position where the band-shaped anti-slip member was attached. Table 1 shows the evaluation results.

Comparative Example 1 A pallet similar to the pallet of Example 1 was manufactured except that no convex strip was provided on the top plate surface and the bottom plate surface.
Table 1 shows the evaluation results.

Comparative Example 2 An ethylene-vinyl acetate copolymer (E) was used as a non-slip member on the top and bottom plates of a pallet obtained in the same manner as in Comparative Example 1.
Five sheets each made of VA) were attached. The EVA sheet had a thickness of 2 mm, a width of 20 mm, and a length that was the same as the pallet width, and the sheets were laminated in the pallet width direction so that the respective sheet intervals were uniform. Table 1 shows the evaluation results.

Comparative Example 3 An ethylene-vinyl acetate copolymer (EVA) sheet was laminated as an anti-slip member on the entire surfaces of the top plate and bottom plate of the pallet obtained in the same manner as in Comparative Example 1. The EVA sheet had a thickness of 2 mm. Table 1 shows the evaluation results.

Comparative Example 4 A pallet having a top plate and a bottom plate having an opening ratio of about 50% and composed of a U-shaped rib connecting the top plate and the bottom plate was used. The size of this pallet was 1400 mm in width, 1100 mm in depth, and 150 mm in height. This pallet had a plurality of ridges having a length of 55 mm, a width of 5 mm, and a height of 0.8 mm, all around the outer peripheral edge of both surfaces of the top plate and the bottom plate. Table 1 shows the evaluation results.

[0031]

[Table 1] ─────────────────────────────────── Comparative Examples 1 2 1 2 3 4 4 ─ ───────────────────────────────── Loading slip ○ ◎ × △ ◎ △ Sliding between pallets ◎ ◎ × △ ○ ◎ Productivity ◎ ○ ◎ ○ △ ○ ───────────────────────────────────

[0032]

As described above in detail, the pallet of the present invention can reduce the slip between the pallet and the load and between the pallet and the pallet at low cost. In addition, the pallet of the present invention has a top plate or a top plate and a bottom plate having an aperture ratio of 20 respectively.
%, The ridges can be freely arranged at necessary places. Further, in the pallet of the present invention, when a plurality of pallets are stacked, the ridges can be used for positioning, and the ends can be aligned and stacked easily.

Further, in the pallet of the present invention, by using a slip preventing member made of a material different from that of the pallet body, the slip between the pallet and the load can be further improved.

Further, in the pallet of the present invention, when a separate anti-slip member is attached to the surface of the pallet, it can be attached between the ridges, and the ridges can be slipped by appropriately selecting the position and interval thereof. It can be used to position the prevention member attachment. Further, since the anti-slip member is arranged between the ridges, there is no risk of the anti-slip member peeling off or falling off from the pallet body even when the load is caught by the anti-slip member.

[Brief description of the drawings]

FIG. 1A is a top view, FIG. 1B is a front view, and FIG. 1C is a side view of a pallet according to an embodiment of the invention.

FIG. 2 is a top view of a pallet according to an embodiment (Embodiment 2) of the present invention.

FIG. 3 is a diagram showing a sliding test method between a pallet and a load (resin bag).

FIG. 4 is a view showing a pallet-pallet slip test method.

FIG. 5 is a top view showing an example of the pallet of the present invention.

[Explanation of symbols]

 1 Pallet 2 Top plate 3 Bottom plate 4 Width side plate 5 Depth direction side plate 6 Fork insertion slot 7 Convex strip 8 Pallet center line 9 Anti-slip member

Front Page Continuation (72) Inventor Shinichi Nagaoka 1-5 Anezaki Kaigan, Ichihara, Chiba Sumitomo Chemical Co., Ltd.

Claims (5)

[Claims] 1. A top plate and a bottom plate made of a resin or a material including a filler therein, and a plurality of ribs are provided so as to connect the top plate and the bottom plate, and one of the ribs is provided. A pallet made of synthetic resin in which a fork for inserting a fork is provided in the part, and the same material as the material forming the top plate or the top plate and the bottom plate on the surface of the top plate or the top plate and the bottom plate. Plural ridges made of material are arranged integrally,
Moreover, a synthetic resin pallet characterized in that the top plate on which the ridges are arranged or the opening ratio of the top plate and the bottom plate is 20% or less. 2. The synthetic resin pallet according to claim 1, wherein the ridges are arranged parallel and / or orthogonal to the fork insertion direction. 3. The synthetic resin according to claim 1, wherein the ridges do not exist on the center line of the top plate or the bottom plate, and are arranged asymmetrically with the center line of the top plate or the bottom plate interposed therebetween. palette. 4. The synthetic resin pallet according to claim 1, wherein the ridges are provided on the top plate or the entire surface of the top plate and the bottom plate. 5. A slip prevention member made of a material having a coefficient of friction larger than that of a material forming the top plate and the bottom plate is arranged between the ridges. The synthetic resin pallet described.