JPH021009B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing synthetic resin pallets used for cargo handling or storage of articles.

The current thinking has been to mold a resin pallet as a series of integral parts, or to mold a semi-finished product that is divided into two parts vertically and weld the two halves together. The mold has a large area, and the investment cost required to manufacture it is enormous. Furthermore, if multiple types of pallets with different sizes were to be manufactured based on the same concept, the investment cost for molds and, by extension, the investment cost for the entire manufacturing equipment would be enormous.
This has a large impact on the pallet unit price. Therefore, although resin pallets are recognized for their excellent performance and durability, due to the cost mentioned above, they are economically viable only in a certain large quantity, and this makes them less attractive than wooden pallets. This is the root cause of the low penetration rate.

The purpose of the present invention is to solve these problems.

The approach taken by the present invention to solve this problem is as follows. That is, first, a "pallet construction board" corresponding to a plurality of divided resin pallets to be finally created is created. They are joined together to create a resin pallet.

something like.

It can be said that the division is roughly equal. Although the number of divisions is not particularly limited, it is not preferable to have too many divisions. Industrially, it is useful to divide it into four parts at most. In other words, generally it is divided into 2, 3
It is divided into four parts.

When divided into two, the two palette configuration boards (hereinafter simply referred to as "composition boards") are congruent. This is the first
Let me explain using Figure 2.

As shown in FIG. 1, the pallet construction board a consists of a rectangular main body 1 and a joining margin 2 integrally connected to one side edge of the rectangular main body 1, and is entirely made of synthetic resin. The longitudinal dimension X and the lateral dimension Y of the rectangular main body 1 are set to constant values, and the protruding dimension Z of the joining margin 2 is adjusted to an arbitrary value within an appropriate range. The length L of the joint allowance portion 2 is set to a constant value. 2X≦Y
Generally, the range is ≦3X, 0<Z≦X/5.

As shown in FIG. 2, two of these pallet constituent plates a are brought into contact with each other at their joint margins 2, 2, and then they are joined together to form a resin pallet A.

FIG. 3 shows the conceptual structure of the molding die K of the construction board a in FIG. 1. 21 is a mold body, and dimensions X and Y are equal to those of component board a. A movable mold frame 22 is located in a groove portion of the mold body 21 that communicates with the cavity 23, and closes the cavity. By displacing this movable formwork 22 in the P and Q directions,
This is to adjust the expected protrusion dimension Z of the joint allowance portion 2. By displacing the movable formwork 22, a plurality of types of construction boards a having the same dimensions X and Y but different dimensions Z are created. And among them, the same kind of things are
It is joined as shown in the figure, and by this, the total width Y
A plurality of types of resin pallets A having the same overall length M and different total lengths M are made. These pallet groups have the same shape and pattern, except that the dimensions of the joining margins 2, 2 are different.

Let us explain the case of three divisions with reference to FIGS. 4 to 6. The mold K is provided with a movable mold frame 22 on opposite sides. When making both ends of the component board a, one movable formwork 22 is moved to a position where no joining margin is created, as shown by the imaginary line. When making the central component board a, the two movable formworks 22 are displaced so that the dimensions Z are equal.

The case of four divisions will be explained with reference to FIGS. 7 and 8. The mold K is provided with movable mold frames 22 on two orthogonally adjacent sides. In this case, the dimension Z of the vertical side and the dimension Z of the horizontal side may be equal or different.

Figure 9 shows the conceptual configuration of a general-purpose mold K.
An example of the configuration board a created by this is shown in the 10th
As shown in the figure. The mold K is provided with movable mold frames 22 on four sides.

The mold shown in FIG. 9 has the functions of the mold shown in FIG. 3, the mold shown in FIG. 4, and the mold shown in FIG. The mold shown in FIG. 7 and the mold shown in FIG. 4 each have the function of the mold shown in FIG. 3.

As can be seen from what has been seen above, the measures taken by the present invention can be described as follows. That is, the method for producing synthetic resin pallets includes the following steps.

[1] The first step is to adjust the planned protrusion dimension of the joint allowance based on the displacement of the movable formwork.

[2] Inject molten resin into the molding cavity,
The second step is to produce a pallet construction board in which a joining margin is connected to the side edge of a rectangular main body.

[3] The third step is to integrally join the prepared multiple pallet configuration boards together by welding or the like at each joining margin.

This is based on the following viewpoints.

By creating multiple types of pallet configuration boards with different protruding dimensions of the joint margins, and integrating similar or different types of pallets, it is possible to create multiple types of resin pallets with different deck areas. The idea is to create.

In this case, in the molding die of the pallet construction board, the part of the mold corresponding to the joining margin is made into a movable formwork that changes its position along the direction in which the joining margin extends from the rectangular main body. The vertical and horizontal dimensions, molding profile, etc. of the mold portion corresponding to the rectangular body that occupies most of the pallet configuration board are determined.
The structure and shape of the movable formwork itself and the structure of the moving mechanism for the movable formwork can be relatively simple.

In other words, in order to make multiple types of pallet configuration boards with different protruding dimensions of the joint allowance, it is sufficient to prepare one molding die equipped with a movable formwork (this means that the manufacturing equipment (This does not mean that the mold is limited to a single mold.) Therefore, the investment cost of the molding die and, by extension, the investment cost of the entire manufacturing equipment can be significantly reduced, and as a result, the unit price of the pallet can be significantly reduced.

In other words, the present invention is based on a drastic reduction in unit costs.
This is extremely useful in promoting the popularization of synthetic resin pallets with excellent performance and durability.

This concludes the gist of the present invention.

Next, let's explain an application example.

FIG. 11 shows a case where the pallet configuration board a of FIG. 1 is made by integrating two deck boards 4 with girders 3 by welding the girders 3 and 3 together. Of course, the entire pallet component board a may be molded at once.

The one in FIG. 12 is the same as that in FIG. 11 except that the protruding dimension W of the girder 3 is different. As a result, the height H also differs. The protrusion dimension W of the girder 3 can also be easily adjusted by changing the position of the movable formwork in one molding die.

A specific example of a combination of the configurations shown in FIGS. 2 and 11 is shown in FIGS. 13 to 16. FIG. 13 shows only one of the four equal parts divided by lines B and C in FIG. FIG. 14 is a front view thereof. 5 is a rib-like piece that constitutes the deck surface, 6 is a through hole, and 7 and 8 are reinforcing bones, which are preferably made of steel pipes. bones 7,8
is encapsulated in resin. Numeral 9 is anti-slip rubber for the article to be placed, 10 and 11 are anti-slip rubber for forks, and 12 is a fork insertion port.

[Brief explanation of drawings]

1 to 12 are structural principle diagrams, respectively. Figures 1, 5, and 10 are plan views of the configuration board, Figures 2, 6, and 8 are plan views of the palette, respectively, and Figures 3, 4, 7, and 8 are plan views of the pallets, respectively. FIG. 9 is a plan view of the mold, and FIGS. 11 and 12 are front views of the pallet. Figure 13 is a plan view of a concrete pallet, showing 1/4 of the whole. FIG. 14 is a front view thereof, FIG. 15 is a sectional view taken along line E--E in FIG. 13, and FIG. 16 is a sectional view of the anti-slip rubber portion. a... Palette configuration board, 1... Rectangular body, 2
. . . Joint allowance, 22 . . . Movable formwork, 23 . . . Molding cavity.

Claims (1)

[Claims] 1. Adjust the planned protrusion dimension Z of the joint allowance 2 based on the displacement of the movable formwork 22, and then
By injecting molten resin into 3, a pallet construction board a in which a joining margin 2 is continuously provided on the side edge of a rectangular main body 1 is produced, and a plurality of pallet construction boards a thus produced are each joined. A method for producing a synthetic resin pallet that is integrally joined at a substitute part 2. 2. The method for producing synthetic resin pallets according to claim 1, wherein the integral joining is performed by thermal welding.