JPH0581027U - Pallet for loading - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a lightweight, highly rigid and durable pallet for loading. [Structure] A pallet 10 having a deck board 11 for loading articles, a hollow girder 20 formed on the back side of the deck board 11, and an in-girder rib 46 and an inter-girder rib 43 on the back surface of the deck board 11. Further, an intra-girder communication rib 44 and an inter-girder communication rib 41, which communicate with each other via the side wall of the girder 20, are provided to relieve stress concentration of the rib.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 INDUSTRIAL APPLICABILITY The present invention relates to a loading pallet, and can be used as a resin pallet for a forklift used when transporting, moving, and storing articles.

[0002]

[Background technology]

 2. Description of the Related Art Conventionally, when carrying various items, a method of loading the items on a pallet and carrying them has been used. Forklifts, cranes, etc. are used as transporting machines, but many pallets are equipped with a fork slot for transporting by forklift. Wood, metal, etc. are also used as materials for such pallets, but recently synthetic resins have been used for reasons such as lighter weight and easier handling, or simplification of the manufacturing process to reduce costs. Many manufactured products are used.

There are two types of forklift resin pallets depending on the installation position of the fork insertion port, and there are two-sided and one-sided types depending on the arrangement of the deck board on which articles are loaded. Depending on the manufacturing method, it can be divided into upper and lower halves, integrated type, square board and rectangular type depending on the shape of the deck board, and injection molding type and press molding type depending on the molding method.

5 to 8 show general examples of conventional resin pallets for forklifts. In FIG. 5, the pallet 10 is an upper and lower split type four-way insertion square resin pallet, and the half-shaped portions 10A and 10B are joined to each other vertically. Then, these half-divided parts 10A and 10B are vertically symmetrical, that is, the pallet 10 is formed by joining substantially the same parts upside down. These half-divided parts 10A and 10B are hollow cylindrical tubes provided on the back surface of each deck board 11 for connecting the deck board 11 forming the loading surface and the upper and lower deck boards 11 respectively. A fork insertion part 30 for inserting a forklift fork is formed between the girders 20. In addition, on the back surface of the deck board 11, a back surface rib 90 is provided inside the girder 20 and in the fork insertion portion 30 which is between the girders 20. Such a pallet 10 is formed by being injection-molded into a vertically divided half-split state, and then welded and joined at the welded portions 13 of the end faces of the upper and lower girders 20.

FIG. 6 shows the basic structure of the inside of the pallet 10 (the back surface in a half-split state). In the figure, the girder 20 is composed of nine girders, four corner girders 21, four inter-angle girders 22 and one central girder 23. The fork insertion portion 30, which is a transportation jig insertion portion, is composed of an inter-girder portion 31 and an inter-girder intersection portion 32. The back surface rib 90 is composed of an inter-girder rib 93 and an in-girder rib 96 (see FIG. 8).

In such a four-sided square pallet 10, each of the four divided blocks is vertically and horizontally symmetrical, and the basic structure of the back rib 90 is also vertically and horizontally symmetrically. ing. FIG. 7 shows a detailed structure of the back ribs 90 of the pallet 10, and FIG. 8 shows a schematic view thereof. In FIG. 7, the back ribs 90 relating to the division of details are partially omitted. Has been.

In the structure of the back rib 90 of the conventional example, the girder part 31 is divided into five parts by the girder ribs 93, and the corner part girders 21 are arranged in a lattice by the girder ribs 96, as seen schematically. The girders 22 are divided into 3 × 4 by the ribs 96 in the girder, and the center girders are divided into 4 × 4 in a grid by the ribs 96 in the girder. Further, the arrangement of the back ribs 90 inside the girders 20 and the fork insertion portions 30 that come between the girders 20, that is, the ribs 96 inside the girders and the ribs 93 between girders are arranged by arbitrary divisions. The ribs 93 between the girders and the ribs 96 inside the girders are not arranged so as to communicate with each other with the side wall of the girder 20 interposed therebetween.

By the way, in such a conventional example, the bending rigidity required for the deck board 11 can be obtained by installing the back rib 90, and when carrying or moving an article by a forklift or the like. The bending of the pallet 10 does not cause inconvenience such as load collapse.

There is also an example such as Japanese Utility Model Publication No. 57-2285 in which a special reinforcing plate 81 is provided in the girder 20 to improve the bending strength of the pallet. In FIG. 9, the reinforcing plate 81 has its both side edges connected to the side walls of the corner girder 21 which are orthogonal to each other, and at the connecting position, the reinforcing ribs 82 between the girders 20 are connected to the side walls of the corner girder 21. It matches the position (position K in the figure), which improves the bending strength of the pallet.

[0010]

[Problems to be solved by the device]

 However, in the example of the pallet 10 shown in FIG. 5 to FIG. 8 described above, since the inter-girder ribs 93 of the inter-girder portion 31 are connected to the side wall of the girder 20 in a T-shape, the connecting position (in FIG. 7). The structure is such that stress tends to concentrate at the position of P), and as a result, there is a problem that the relevant part is easily broken during loading.

Further, in the example of Japanese Utility Model Publication No. 57-2285, which is provided with a special reinforcing plate 81, the reinforcing plate 81 connects both side edges to the side walls of the corner girder 21 which are orthogonal to each other, and the bending strength of the pallet is increased. However, since the reinforcing plate 81 must be installed diagonally to the side wall of the corner girder 21, there is a problem that the grid layout, which is the conventional basic structure, must be changed. was there.

An object of the present invention is to provide a loading pallet that is lightweight, highly rigid, and excellent in durability.

[0013]

[Means for Solving the Problems]

 The present invention has a deck board for loading articles, a hollow girder formed on the back side of the deck board, and ribs formed in the girder inner part and the girder part on the back surface of the deck board. At least one rib between the girders is continuously formed on substantially the same line as the rib inside the girder. Here, the thickness of the rib formed between the girders is thicker than the rib between the other girders, and the thickness of the rib formed between the girders is continuous with the rib between the girders. It is desirable that the rib be thicker than or equal to the rib in the girder. Further, it is desirable that the ribs between the girders and / or the ribs in the girders that are continuously formed with each other have a hollow structure.

[0014]

[Action]

 In the present invention, since the ribs inside the girders and the ribs between the girders are communicated with each other on at least one location on the substantially same line through the side walls of the girders, the ribs and the side walls of the girders are not easily connected to each other when the article is transported. The stress concentration at the connection portion of is relaxed.

Further, by connecting the ribs in the girders with the ribs between the girders as described above, it is possible to provide rigidity without using an extra material, which enables weight reduction and cost reduction. By these, the above-mentioned object is achieved.

[0016]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. The pallet 10 of the present embodiment is an upper / lower split type four-sided square resin pallet, and its basic structure is substantially the same as that of the conventional example shown in FIG. 5, but the structure of the back rib 40 is different. Therefore, the description of the common part is omitted for simplification, and only the structure of the back rib 40, which is a different part, will be described below.

The structure of the back rib 40 of this embodiment is schematically shown in FIG. 1 (a part of the back rib 40 relating to the division of details is omitted), and the girder 20 The arrangement and the number of divisions of the back ribs 40 in the inside are the same as the arrangement and the division number of the back ribs 90 of the conventional example shown in FIG. Further, the arrangement of the back ribs 40 between the beams 20 is different from that of the conventional example shown in FIG. 8, but the number of divisions is the same. In FIGS. 1 and 2, an in-girder communication rib 44, which is an in-girder rib 46, is provided in the girder 20, and an inter-girder rib 43 is provided in the inter-girder portion 31, which is between the girders 20. The inter-girder rib 43 is composed of an inter-girder communication rib 41 and an inter-girder communication rib 42. The in-girder communication ribs 44, the inter-girder communication ribs 41, and the inter-girder communication ribs 42 constitute a back surface rib 40.

The intra-girder communication ribs 44 and the inter-girder communication ribs 41 are connected at a position S in FIG. 2 like one continuous rib sandwiching the girder 20. Further, the in-girder communication ribs 44 and the inter-girder communication ribs 41 have a hollow structure as shown in FIG. 3, and FIG. 4 (A) shows the cross-sectional shape of the inter-girder communication ribs 41 and FIG. 4 (B). Shows the cross-sectional shape of the intra-girder communication rib 44. Both of these cross-sectional shapes have trapezoidal portions of substantially the same shape and size, and the height HA of the trapezoidal portion of the inter-girder communication rib 41 and the height HB of the trapezoidal portion of the intra-girder communication rib 44 are The trapezoidal portions have the same thickness DA and DB. Further, a part of the communication rib 44 in the girder is provided with a rib portion (the height combined with the height of the trapezoid portion is L) that is thinner than the thickness DB of the trapezoid portion at the tip of the trapezoid portion, and the tip of the rib is The welded portion 13 is a vertically split type. Further, the thickness DA of the inter-digit communication rib 41 is thicker than that of the inter-digit communication rib 42.

According to this embodiment as described above, the in-girder communication ribs 44 and the inter-girder communication ribs 41 are connected at the position S in FIG. 2 like a single continuous rib sandwiching the girder 20. Therefore, the stress concentration at the relevant portion when the article is transported can be relaxed as compared with the case of the conventional T-shaped connection (position P in FIG. 7). Therefore, the durability is improved, and the disadvantage that the pallet 10 is damaged can be eliminated.

Further, since the thickness DA of the girder communication rib 41 is thicker than that of the girder non-communication rib 42, it is possible to reduce the weight because rigidity is given only to necessary portions without using an extra material. And it is possible to reduce the cost. Since a part of the communication rib 44 in the girder has a rib portion thinner than the trapezoidal portion thickness DB at the tip of the trapezoidal portion, it is possible to secure the necessary upper and lower split type welded portions 13. Can be kept.

Further, since the intra-girder communication ribs 44 and the inter-girder communication ribs 41 have a hollow structure, the weight can be reduced while maintaining the rigidity. Then, these hollow portions can be easily formed by, for example, a molding method using a gas injection method (see Japanese Patent Application No. 03-166344, etc.), and the pallet 10 can be manufactured easily.

Further, the ribs 46 in the girder need not be arranged obliquely with respect to the side wall of the girder 20 unlike the reinforcing plate 81 in FIG. Since it can be easily realized only by changing the arrangement of the division of the inter-girder rib 43 and / or the in-girder rib 46 in, a large design change can be dispensed with.

By the way, in order to confirm the effect of the present invention, the following experiment was conducted. The composition of the five loading pallets used in the experiment is as follows. The experimental example 1 of the embodiment is a pallet of a split type and a double-sided type, which is the same as the embodiment shown in FIGS. 1 to 4 except that the rib has no hollow portion. The inter-digit communication rib 41 is present at 31. (The number of ribs 43 between girders and ribs 46 within a girder is the same as in Comparative Example 1)

The experimental example 2 of the example is the same as the experimental example 1 of the example, except that it is a one-sided one-use type. The width of the inter-girder communication rib 41 is 5 mm, the width of the intra-girder communication rib 44 is 5 mm, and the width of the inter-girder non-communication rib 42 is 3 mm.

The experimental example 3 of the embodiment is an upper and lower split type double-sided type pallet, which is the same as the above-described embodiment shown in FIGS. 1 to 4, and the inter-girder portion 31 has an inter-girder communication rib 41. Exists, and the girder communication rib 41 and the girder communication rib 44 have a hollow structure. The dimensions of the inter-girder communication rib 41 and the intra-girder communication rib 44 are HA = HB = 27 mm, DA = 10 mm, L = 74.5 mm in FIG.

Comparative Example 1 is an upper and lower split type double-sided type pallet, which is the same as the conventional example shown in FIGS. 5 to 8, and there is no communication rib in the inter-beam portion 31. (The number of ribs 43 between girders and the number of ribs 46 within a girder are the same as in Experimental Example 1 of the embodiment.) Comparative Example 2 is the same as Comparative Example 1 except that it is an integrated single-sided type.

The material of the loading pallets in the above five examples is all polypropylene (PP), and in any case, the outer diameter is a square of 1100 mm × 1100 mm, which is a four-way fork type, injection molding (injection molding) Is.

A bending strength test was performed on these five examples based on JISZ0602, and the maximum amount of deflection was measured. In addition, a trial calculation was performed using a finite element method structural analysis simulation program to investigate the stress distribution. The above results are shown in Table 1.

[0029]

[Table 1]

According to the table, stress concentration is observed in a part of the rib in Comparative Examples 1 and 2, but this is not observed in Experimental Examples 1, 2, and 3 of the example, and there is no defective portion as a whole. In addition, the weight of the pallet does not differ between the case with the communication rib structure and the case without the communication rib structure, and the maximum deflection amount is also smaller with the communication rib structure, so the effect of the present invention is remarkable.

It should be noted that the present invention is not limited to the above-mentioned embodiment, and the following modifications and the like are also included in the present invention. For example, in the above-described embodiment, the in-girder rib 46 is composed of only the in-girder communication rib 44. However, like the inter-girder rib 43, the in-girder communication rib 45 is provided, and the in-girder communication rib 44 and the in-girder communication rib 44 are provided. The in-girder rib 46 may be configured by the communication rib 45.

Further, regarding the number of divisions of the girder 20 and the fork insertion portion 30, in the above-described embodiment, the inter-girder portion 31 is divided into five by the inter-girder rib 43 in a schematic view, and the corner portion girder 21, the inter-girder girder 22, The central girder 43 is divided into 3 × 3 divisions, 3 × 4 divisions, and 4 × 4 divisions in a grid pattern by the ribs 46 inside the girders, but any number of divisions may be used, that is, through each side wall of the girder 20. At least one pair of the intra-girder communication ribs 44 and the inter-girder communication ribs 41 may be provided.

Although the hollow ribs of the intra-girder communication ribs 44 and the inter-girder communication ribs 41 have a trapezoidal shape, any shape can be used as long as the hollow section can be formed and the required rigidity can be secured. It may have a shape. Then, these hollow portions are formed by the gas injection method, but other methods may be used and the shape of the hollow portions is arbitrary. Further, these hollow portions may be provided only in one of the intra-girder communication ribs 44 or the inter-girder communication ribs 41 or not in both if the overall weight of the pallet 10 does not become too heavy. ..

Further, the pallet 10 of the above embodiment is an upper and lower split type four-way insertion square resin pallet, but depending on the installation position of the fork insertion opening, two-way insertion and four-way insertion, depending on the arrangement of the deck board for loading the articles. There are various specifications such as double-sided use type and single-sided use type, upper and lower split type and integrated type depending on the manufacturing method, square type and rectangular type depending on the shape of the deck board, injection molding type and press molding type depending on the molding method. The structure of the back rib 40 of the present invention can also be applied to objects.

Further, although the pallet 10 of the above embodiment is a pallet for a forklift, it is not limited to a forklift and may be for a crane or other transportation means. A transportation jig insertion portion such as the fork insertion portion 30 may be formed between the two.

Further, in the above embodiment, the trapezoidal portion of the inter-girder communication rib 41 has the same thickness DA and the trapezoidal portion of the intra-girder communication rib 44 has the same thickness DB. By making the thickness DA larger than the thickness DB of the trapezoidal portion of the intra-girder communication rib 44, the rigidity of the pallet 10 can be further increased and the deck board 11 can be prevented from bending. At this time, since the communication ribs 44 in the girder are located inside the girder 20, even if the thickness DB of the trapezoidal portion is reduced to the extent that the communication effect is not lost, that is, the stress concentration is not accompanied, the pallet 10 can be formed. The rigidity does not decrease and the weight can be reduced. Further, the height HA of the trapezoidal portion of the inter-girder communication rib 41 and the height HB of the trapezoidal portion of the intra-girder communication rib 44 are the same, but different heights are provided unless an extremely different stress is concentrated. May be Since the thickness of the girder discontinuity rib 42 is usually 3 to 4 mm, it is appropriate that the trapezoidal part thickness DA of the girder communication rib 41 and the trapezoidal part thickness DB of the intragirder communication rib 44 be about 5 to 7 mm. However, these dimensions are not absolute.

Further, the pallet 10 of the above-described embodiment is a resin pallet, and polypropylene (PP), high density polyethylene (HDPE), other resin, etc. are applied, but not limited to resin, metal material or An inorganic material such as ceramics may be used, and any material may be used as long as the structure of the back rib 40 can be adopted.

[0038]

[Effect of the device]

 As described above, according to the present invention, the ribs inside the girders and the ribs between the girders communicate with each other on at least one location on the substantially same line via the side walls of the girders. Stress concentration at the connecting portion between the rib and the side wall of the girder can be relaxed, and durability can be improved.

[Brief description of drawings]

FIG. 1 is a schematic view showing a back rib structure according to an embodiment of the present invention.

FIG. 2 is an enlarged view showing a main part of the embodiment.

FIG. 3 is a perspective view showing a main part of the embodiment.

FIG. 4 is a cross-sectional view of the communication rib of the above embodiment.

FIG. 5 is a perspective view showing a conventional example.

FIG. 6 is a schematic view showing a back surface structure of the conventional example.

FIG. 7 is an enlarged view showing a main part of the conventional example.

FIG. 8 is a schematic diagram showing a back rib structure of the conventional example.

FIG. 9 is an enlarged view showing a main part of another conventional example.

[Explanation of symbols]

 10 Pallet 11 Deck board 13 Welding part 20 Digit 21 Corner girder 22 Inter-girder girder 23 Center girder 30 Fork insertion part which is a jig insertion part for transportation 31 Inter-girder part 32 Inter-girder cross part 40 Back rib 41 Girder communication rib 42 Girder communication rib 43 Girder rib 44 Girder communication rib 45 Girder communication rib 46 Girder rib

Claims (3)

[Scope of utility model registration request] 1. A deck board for loading articles,
There is a hollow girder formed on the back side of this deck board, and ribs formed in the girder inner part and inter-girder part on the back surface of the deck board, and at least one rib between the girders is in the girder. The loading pallet, which is continuously formed substantially on the same line as the rib. 2. The load pallet according to claim 1, wherein a thickness of ribs between the continuously formed girders is thicker than ribs between other girders, and the continuously formed girders. The thickness of the rib between the ribs is equal to or larger than the rib in the girder continuous with the rib between the girders. 3. The load pallet according to claim 1 or 2, wherein the ribs between the girders and / or the ribs inside the girders that are continuously formed with each other have a hollow structure. A pallet for loads that is characterized by.