JP3518623B2 - Integrated molding pallet made of synthetic resin and molding method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin pallet which is most suitable for transporting and storing various articles using a forklift, a pallet truck and the like, and a molding method thereof.

[0002]

BACKGROUND ART Synthetic resin pallets for which pallet trucks can be used have been conventionally known, but most of them are formed by separately molding the upper half and the lower half of the pallet and heat-welding them in a subsequent process, or It is joined with bolts and nuts. By dividing the upper and lower sides of these pallets, it is easy to set the lower half to the optimum shape for using the pallet truck.

However, a pallet in which the upper half and the lower half are separately molded and bonded together requires a molding process for two pallets and a bonding process, resulting in poor productivity. For example, in the case of fusion molding, it takes about 6 minutes / sheet to weld after molding the upper and lower parts. Further, the welding type pallet requires a work for removing burrs generated at the welding portion at the time of welding, which is more troublesome. Moreover, it is difficult to catch the burr that has been caught on the deck boards or the like. Personnel and equipment must be required to process this burr. If the burrs are not sufficiently removed, there is a risk that the burrs may enter as foreign matter when the pallet is placed on the conveyor of the production line for other products. In addition, the welded type pallet has a disadvantage that the upper and lower welded portions are inevitably misaligned, so that the company name or the like cannot be printed on the entire side surface. On the other hand, when joining the upper and lower parts with bolts and nuts, the joints are inferior in strength, and since the bolts and nuts are metal, they rust during use and the strength decreases. There is.

There is also a synthetic resin pallet which is integrally molded by a fixed mold and a movable mold, but the back side deck board portion along the fork insertion hole is not flat and has a groove. , The wheels attached to the forks get caught, especially when loading and unloading the pallet truck,
Furthermore, since at least a part of the front side deck board part corresponding to the part other than the opening part of the back side deck board is a plate body having a relatively wide opening part, heavy load is concentrated there. There is a problem that it will cause damage etc. There are pallets containing 10 to 30% of inorganic filler such as talc and calcium carbonate to increase the strength, but the weight of the pallet becomes heavy, the impact strength decreases, and the workability is poor. There is a drawback of.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a synthetic resin integrally molded pallet which is excellent in bending strength, has no inconvenience when using a pallet truck, and has excellent productivity, at a low cost.

[0006]

As a result of intensive studies, the inventors of the present invention have found that a synthetic resin pallet obtained by the integral molding method solves the problems of the prior art and has reached the present invention. .

That is, according to the present invention, the edge of the rectangular opening formed on the back side deck board along the lower edge of the fork insertion opening and the fork insertion hole is perpendicular to the fork insertion direction. In a two-way or four-way synthetic resin integrally-molded pallet that is approximately inclined,
The back side deck board of the fork insertion hole is a plate body across the mouth portion, and the front side deck board of the fork insertion hole is formed with a grid-like plate body over the entire length. The present invention relates to a synthetic resin integrally molded pallet.

According to the present invention, in the above pallet, the four
Back side of the insertion hole A lattice-shaped rib is provided on the back side of the plate body of the deck board, and / or a through hole is provided in the plane portion of the plate body, which is made of synthetic resin. The present invention relates to a molding pallet.

According to the present invention, in the above pallet, both ends of the upper and lower back side deck boards which do not correspond to the fork insertion holes do not overlap vertically between the front and back side deck boards in the middle and corner portions. U open in position
The present invention relates to a synthetic resin integrally molded pallet, characterized in that a crosspiece having a groove is formed.

Further, according to the present invention, the front side deck board is formed by the slide core which is inserted from the side of the fork insertion hole and the fixed mold, and the back side deck board is inserted from the side of the fork insertion hole. The present invention also relates to a molding method of the synthetic resin pallet, which is characterized in that molding is performed by a slide core, a movable mold, and an inclined block incorporated in the movable mold.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. 1 is a plan view showing an example of a two-way synthetic resin pallet according to the present invention, FIG. 2 is a bottom view of the synthetic resin pallet shown in FIG. 1, and FIG. 3 is a synthetic resin pallet shown in FIG. 1 is a front view, FIG. 4 is a side view of the synthetic resin pallet shown in FIG. 1, FIG. 5 is a sectional view taken along line AA in FIG. 1, and FIG. 6 is a sectional view taken along line BB in FIG. Explanatory view showing a state in which the fork of the pallet truck is inserted into the
9 is a sectional view showing a state where the synthetic resin pallet shown in FIG. 1 is being molded. 10 is a schematic plan view showing a 4-way synthetic resin pallet, and FIG. 11 is FIG.
0 is a schematic bottom view of the synthetic resin pallet shown in FIG. 0, FIG. 12 is a schematic sectional view taken along the line AA in FIG. 10, and FIG. 13 is a schematic sectional view taken along the line BB in FIG. 14 is a schematic side view of the synthetic resin pallet shown in FIG. 10 and FIG.
5 is a schematic view of a slide core portion in a mold for molding a 4-way insertion pallet. 5 corresponds to a sectional view taken along the line AA in FIG. 10 in the case of a four-way pallet, and FIG. 6 is taken along the line BB in FIG. 10 in the case of a four-way pallet. Corresponds to a cross-sectional view.

The synthetic resin pallet according to the present invention is integrally molded using a thermoplastic resin such as polyethylene, polypropylene or ABS resin. The two-way synthetic resin pallet has a front deck board 1 and a back deck board 2, and a tubular girder 3 and an intermediate portion at the corners that reach from the front deck board 1 to the back deck board 2 And a fork insertion hole 5 is provided between the cylindrical girder 3 at the corner and the cylindrical girder 4 at the middle portion, and the rear side deck board 2 below the fork insertion hole 5 is formed. Is opening 6
Are formed two by two. In the case of a 4-way pallet, two fork insertion holes 5 are formed in each of the vertical direction and the horizontal direction of the pallet, and the front side deck board 1
A tubular girder 3 at the corner and a tubular girder 4 at the middle are formed from the bottom to the back side deck board 2, and a fork is inserted between the tubular girder 3 at the corner and the tubular girder 4 at the middle. A hole 5 is provided.

In the two-way pallet according to the present invention, the front side deck board 1 above the fork insertion hole 5 is provided with the grid-like plate bodies 7 continuous vertically and horizontally over the entire length of the synthetic resin pallet. As a result, sufficient strength can be imparted to the synthetic resin pallet. On the back side deck board 2 below the fork insertion hole 5, a plate body 9 at the end and a plate body 1 at the middle portion having a flat surface portion 8 along the fork insertion hole 5 are provided.
0 is provided so as to sandwich the opening 6. Similarly, in the case of a four-way insertion pallet, a grid-like plate that is continuous in the vertical and horizontal directions is formed over the entire length on the front side deck board 1 above the fork insertion hole 5, and the back side below the fork insertion hole 5 is formed. The deck board 2 is provided with a plate body 9 at an end and a plate body 10 at an intermediate portion having a flat surface portion along the fork insertion hole 5 with the opening 6 interposed therebetween. In such a pallet of the present invention, a conventional pallet in which the surface side deck board above the fork insertion hole does not have a lattice shape has a deflection of 12.6 mm under a load of 1000 kg, but a deflection of 9.
It is as small as 5 mm and has excellent strength.

At the ends of the plate 9 at the end and the plate 10 at the middle of the two-way pallet on the side of the opening 6, that is, at the edge of the opening 6 perpendicular to the fork insertion direction. The inclined surface 11 is formed. Further, the lower edge portion of the fork insertion opening formed on the side surface portion of the pallet is inclined outward so that the pallet track can be easily inserted. Is formed. The inclination of the inclined surfaces 11 and 12 is not particularly limited as long as it is an angle that allows the pallet truck to easily move in and out, but is preferably about 20 to 40 °. As a result, the fork 13 of the pallet truck can be extremely smoothly inserted into the synthetic resin pallet without being caught by the inclined surfaces of the fork insertion opening and the opening 6 of the back side deck board 2. Lattice-shaped ribs 14 are provided on the lower surfaces of the plate 9 at the end and the plate 10 at the middle.
Is formed, whereby the end plate 9 and the intermediate plate 10 can be strengthened. A through hole 15 for draining water is provided in the plate body 9 at the end and the plate body 10 at the middle part. Further, in the case of a 4-way pallet, the opening 6 which is perpendicular to the fork insertion direction of the back side deck board 2 is formed.
The same inclined surface 6 as that of the two-way insertion is formed on all of the edge portions of the rear side deck board 2 along the fork insertion hole, and the plate body 9 at the end and the plate body 10 at the middle portion are for draining water. The grid-like ribs 14 are formed on the through holes 15 and their lower surfaces in the same manner as the two-way insertion pallet.

In the tubular girders 3 at the corners and the tubular girders 4 in the middle of the two-way pallet, the front side deck board 1 extends in the same direction as the fork insertion holes 5 and is opened inward. A U-shaped groove 1 having a groove 16 formed therein and extending in the same direction as the fork insertion hole 5 is formed on the back side deck board 2 and opened inward.
7 is formed at a position that does not vertically overlap the U-shaped groove 16.
The U-shaped groove 16 and the U-shaped groove 17 are located in opposite directions, and are connected to each other by reinforcing plates extending inward from their respective side edges to form a crosspiece 18. Also, the tubular girders 3 at the corners
At each end of the tubular girder 4 in the middle portion, the front side deck board 1 is formed with an inwardly opening U-shaped groove 19 extending in a direction perpendicular to the fork insertion hole 5, and the back side deck is formed. A U-shaped groove 20 that extends in a direction perpendicular to the fork insertion hole 5 and opens inward is formed in the board 2 at a position where it does not vertically overlap. These U-shaped grooves are connected to each other by a reinforcing plate to form a crosspiece 18. In the case of a four-way pallet, the fork insertion holes are formed on all sides of the pallet, so that the fork insertion is based on either the vertical or horizontal direction of the fork insertion, similar to the two-way pallet. A crosspiece 18 having a U-shaped groove is formed in each tubular girder.

In the two-way synthetic resin pallet according to the present invention, the cylindrical girders 3 at the corners and the middle part having the crosspieces 18 each having a U-shaped groove are provided so as to have the above-mentioned structure. The cylindrical girder 4 is fixed to the fixed mold 21 and the movable mold 2.
2, the grid plate 7 of the front deck board 1 above the fork insertion hole 5 is molded by the slide core 23 and the fixed mold 21 forming the fork insertion hole 5,
Further, the plate body 9 at the end portion having the grid-like ribs 14 and the plate body 10 at the intermediate portion of the back side deck board 2 below the fork insertion hole 5 are molded by the slide core 23 and the movable mold 22, and the back side. The inclined surface 11 of the opening 6 of the deck board is formed by the movable mold 22 and the inclined block 24 incorporated in the movable mold 22. Regarding the side surface of the pallet, one side on the fork insertion hole side is the slide core 23.
And the fixed die 21, the other surface on the fork insertion hole side is different from the slide core 23 and the fixed die 2
1, and the side surface on the non-fork insertion hole side is molded by a slide core different from the slide core 23 and the movable die 22, respectively.

That is, as shown in FIG.
Slide core 23, movable mold 22, and movable mold 2
The synthetic resin is injected into the cavity in a state where the inclined block 24 incorporated in 2 is closed. Next, as shown in FIG. 8, the slide core 23 and the movable mold 22 are opened. After that, as shown in FIG. 9, the inclined block 24 may be removed from the molded synthetic resin pallet. When the movable mold 22, the tilt block 24, the slide core 23, etc. are closed, the movable mold 22, the tilt block 24, the slide core 23, etc. may be moved in the opposite manner to the above.

In the case of the four-way pallet of the present invention,
Although it can be molded in the same manner as a two-way pallet, for example, a slide core 23 having a shape as shown in FIG. 15 is used, and an inclined block 24 incorporated in a movable mold is provided in the opening 6 of the back side deck board 2. Four pieces are required to form four sides. The slide core 23 in this case is shown in FIG.
As shown in Fig. 5, the slide core parts of a, b, c and d are inserted from four sides, and the side surface of the pallet and the side wall of the fork insertion hole are formed by the combination with the fixed mold and the movable mold. become.

[0019]

The synthetic resin pallet according to the present invention is
A grid-like plate that extends vertically and horizontally on the front deck board above the fork insertion hole is formed over the entire length of the synthetic resin pallet, so it is necessary to carry and store various items. Bending strength is obtained.

Further, in the synthetic resin pallet according to the present invention, the pallet track can be optimally used by providing the inclined surface at the opening of the back side deck board. Furthermore, since the synthetic resin pallet according to the present invention can be integrally molded, it can be provided at a lower cost than a bonded pallet having the same performance.

[Brief description of drawings]

FIG. 1 is a plan view showing an example of a two-way synthetic resin pallet according to the present invention.

FIG. 2 is a bottom view of the synthetic resin pallet shown in FIG.

FIG. 3 is a front view of the synthetic resin pallet shown in FIG.

FIG. 4 is a side view of the synthetic resin pallet shown in FIG.

5 is a cross-sectional view taken along the line AA in FIG.

6 is an explanatory diagram showing a state in which a fork of a pallet truck is inserted in a cross section taken along the line BB in FIG.

FIG. 7 is a cross-sectional view showing a state where the synthetic resin pallet shown in FIG. 1 is being molded.

FIG. 8 is a cross-sectional view showing a state where the synthetic resin pallet shown in FIG. 1 is being molded.

9 is a cross-sectional view showing a state where the synthetic resin pallet shown in FIG. 1 is being molded.

FIG. 10 is a schematic plan view showing an example of a four-way synthetic resin pallet according to the present invention.

11 is a schematic bottom view of the synthetic resin pallet shown in FIG.

12 is a schematic cross-sectional view taken along the line AA in FIG.

13 is a schematic cross-sectional view taken along the line BB in FIG.

14 is a schematic side view of the synthetic resin pallet shown in FIG.

15 is a schematic view of a slide core portion in a mold for molding the synthetic resin pallet shown in FIG.

[Explanation of symbols]

1 Front side deck board 2 Back side deck board 3 Corner tubular girder 4 Intermediate tubular girder 5 Fork insertion hole 6 Opening 7 Lattice plate 8 Plane 9 Plate 10 at the end Plate 11 Sloping surface 12 Sloping surface 14 Lattice rib 15 Through hole 16 U-shaped groove 17 U-shaped groove 18 Crosspiece 19 U-shaped groove 20 U-shaped groove 21 Fixed mold 22 Movable mold 23 Slide core 24 Slant block

Front page continuation (58) Fields surveyed (Int.Cl. ⁷ , DB name) B65D 19/24 B29C 33/42 B29C 45/33 B65D 19/38 B29L 24:00

Claims (7)

(57) [Claims] 1. A lower edge portion of a fork insertion opening and a rectangular opening formed on a back side deck board along a fork insertion hole, a side edge portion of which is perpendicular to a fork insertion direction is inclined outwardly. In the synthetic resin integrally molded pallet, the back side deck board below the fork insertion hole is
A plate body at an end portion and a plate body at an intermediate portion having a flat portion along the fork insertion hole are provided with the opening portion sandwiched therebetween, and a lattice-shaped plate body is provided on the front side deck board of the fork insertion hole. Is formed over its entire length, and is a synthetic resin integrally molded pallet. Wherein said fork insertion holes said back side deck board synthetic resin integrally molded pallet of claim 1, wherein the grid-like ribs on the back side of the plate body is provided in the. Wherein said fork insertion holes said back side deck board said plate member of synthetic resin integrally molded pallet of claim 1 or claim 2, wherein a through hole is provided in the flat portion of the. 4. A between the surface deck board and the back side deck board of the intermediate portion and the corner portion of the pallet which does not correspond to the fork insertion holes, the U-shaped groove open inwardly in a position that does not cover the top and bottom on both ends The synthetic resin integrally-formed pallet according to any one of claims 1 to 3, wherein the crosspieces are formed. 5. A synthetic resin molded pallet according to any one of claims 1 to 4, characterized in that a 2-way entry. 6. The synthetic resin integrally-formed pallet according to claim 1, wherein the pallet is a four-way insert. 7. The synthetic resin integrally-molded powder according to claim 1.
Molding method for synthetic resin pallets that integrally molds pallets
Method, the tubular girders at the corners that do not correspond to the fork insertion holes and
The inside of the tubular girder is molded by a fixed mold and a movable mold, and the deck board on the front side above the fork insertion hole is fixed to the flap.
A slide core for forming a fork insertion hole and the fixed mold
Molded by, 該Fu the back surface side deck board below the fork insertion holes
A slide core that forms a fork insertion hole and the movable mold
Molded by an inclined block incorporated in the movable mold, the opening of the back side deck board is movable with the movable mold.
Synthesis formed by the inclined block incorporated in the mold
A method for integrally molding a resin pallet, comprising: the fixed mold, the slide core, the movable mold,
Closed state of the tilt block incorporated in the movable mold
Inject the synthetic resin into the cavity with
Docoa, the movable mold, and the tilt incorporated in the movable mold
Open the slant block and then move the slant block to the movable
Synthetic resin pallet characterized by being moved from the mold
Integrated molding method.