阅读说明：本技术 货盘、货盘堆叠系统和货盘堆叠方法 (Pallet, pallet stacking system and pallet stacking method ) 是由 浅见大辅 伊原智章 重政拓海 于 2021-03-31 设计创作，主要内容包括：本发明涉及货盘、货盘堆叠系统和货盘堆叠方法。根据本公开的第一方面的货盘是能够在上下方向上堆叠的货盘,其中,设置在下层中的货盘的多个支柱的上端部被插入到在设置在上层中的货盘的支柱的下端部中设置的被插入部中。所述支柱中的至少一个支柱的高度高于其它支柱的高度。(The invention relates to a pallet, a pallet stacking system and a pallet stacking method. A pallet according to a first aspect of the present disclosure is a pallet that can be stacked in an up-down direction, wherein upper end portions of a plurality of columns of the pallet provided in a lower layer are inserted into inserted portions provided in lower end portions of columns of the pallet provided in an upper layer. At least one of the pillars has a height higher than that of the other pillars.)

1. A pallet stackable in an up-down direction, wherein upper end portions of a plurality of pillars of the pallet provided in a lower layer are inserted into inserted portions provided in lower end portions of pillars of the pallet provided in an upper layer, wherein a height of at least one of the pillars is higher than a height of the other pillars.

2. The pallet according to claim 1, comprising a guide portion in a lower portion of each of the inserted portions, wherein when the pallet provided in the upper layer is stacked on the pallet provided in the lower layer, the guide portion of the inserted portion of the pallet provided in the upper layer guides the body portion provided above the guide portion of the inserted portion of the pallet provided in the upper layer to upper end portions of the posts of the pallet provided in the lower layer.

3. The pallet according to claim 1 or 2, wherein the depth of the inserted portion of the leg having a height higher than the height of the other leg is deeper than the depth of the inserted portion of the other leg.

4. The pallet according to claim 3, wherein a difference between a depth of the inserted portion of the leg having a height higher than that of the other leg and a depth of the inserted portion of the other leg is equal to a difference between a height of the leg having a height higher than that of the other leg and a height of the other leg.

5. The pallet according to any one of claims 1 to 4, wherein:

the strut has a polygonal shape or a shape with a rotation stopper; and is

An inner peripheral shape of at least a part of the inserted portion is larger than an outer peripheral shape of the pillar, and has a polygonal shape corresponding to the outer peripheral shape of the pillar or a shape with a rotation stopper.

6. A pallet stackable in an up-down direction, wherein upper end portions of a plurality of pillars of a pallet provided in a lower layer are inserted into inserted portions provided in lower end portions of pillars of a pallet provided in an upper layer, the pallet comprising a cup portion provided in at least one of the pillars so as to be slidable in a height direction of the pillars, wherein the cup portion protrudes from a lower end portion of the inserted portion when the pallet is lifted.

7. The pallet according to claim 6, comprising a guide in a lower portion of each of the inserted portions, wherein:

a guide portion of an inserted portion of a pallet provided in the upper deck guides a body portion provided above a guide portion of an inserted portion of a pallet provided in the upper deck to an upper end portion of a pillar of a pallet provided in the lower deck when the pallet provided in the upper deck is stacked on the pallet provided in the lower deck; and is

The cup portion covers a lower end portion of the guide portion when a pallet disposed in the upper layer is lifted.

8. A pallet stacking system comprising:

a pallet according to any one of claims 1 to 7;

a self-propelled mobile body that lifts and lowers the pallet; and

a detection unit provided in the moving body to detect a preset pillar in the pallet.

9. A pallet stacking method that is a method for stacking a pallet, in which upper end portions of a plurality of stays of the pallet provided in a lower deck are inserted into inserted portions provided in lower end portions of the stays of the pallet provided in an upper deck, the pallet stacking method comprising:

disposing the pallet disposed in the upper deck on an upper side of the pallet disposed in the lower deck, wherein at least one of the columns has a height that is higher than the heights of the other columns;

lowering the pallet disposed in the upper deck and inserting the upper end portions of the columns of the pallet disposed in the lower deck, which are higher in height than the other columns, into the inserted portions of the pallet disposed in the upper deck; and

further lowering the pallet disposed in the upper deck, and inserting the upper end portions of the other columns of the pallet disposed in the lower deck into the inserted portions of the pallet disposed in the upper deck.

10. A pallet stacking method that is a method for stacking a pallet, in which upper end portions of a plurality of stays of the pallet provided in a lower deck are inserted into inserted portions provided in lower end portions of the stays of the pallet provided in an upper deck, the pallet stacking method comprising:

lifting a pallet provided in the upper layer and having a cup portion provided in at least one of the support columns so as to be slidable in a height direction of the support column, so that the cup portion protrudes from a lower end portion of the inserted portion;

lowering a pallet disposed in the upper deck and inserting upper ends of pillars of the pallet disposed in the lower deck into cups of the pallet disposed in the upper deck;

rotating a pallet disposed in the upper tier about upper ends of posts of the pallet disposed in the lower tier to align upper ends of the posts of the pallet disposed in the lower tier with inserted portions of the pallet disposed in the upper tier, wherein the upper ends are inserted into cups of the pallet disposed in the upper tier; and

the pallet provided in the upper deck is further lowered, and the upper end portions of the columns of the pallet provided in the lower deck are inserted into the inserted portions of the pallet provided in the upper deck.

Technical Field

The present disclosure relates to a pallet, a pallet stacking system, and a stacking method, and, for example, particularly to a pallet which can be stacked in an up-down direction in which upper end portions of a plurality of pillars of a pallet provided in a lower layer are inserted into inserted portions provided in lower end portions of a pallet provided in an upper layer; to a pallet stacking system; and to a stacking method.

Background

Generally, a pallet has a configuration in which upper end portions of a plurality of columns of the pallet disposed in a lower layer are inserted into an inserted portion provided in a lower end portion of the pallet disposed in an upper layer so that the pallets can be stacked in an up-down direction. At this time, unless the upper end portions of the columns of the pallets disposed in the lower layer and the inserted portions of the pallets disposed in the upper layer are disposed with high accuracy, the pallets cannot be stacked.

In view of this, japanese unexamined patent application publication No. 2018-58679 (JP 2018-58679A) discloses a technique of detecting the inclination and center positions of pallets disposed in a lower layer using a plurality of two-dimensional distance meters provided in a forklift to adjust the stacking position of pallets disposed in an upper layer based on the detection result.

Disclosure of Invention

The applicant has found the following problems. The technique described in JP 2018-58679A requires the use of a plurality of two-dimensional distance meters for adjusting the stacking position of the pallet provided in the upper layer, and therefore the cost increases for accurately stacking the pallet.

In view of such problems, the present disclosure realizes a pallet, a pallet stacking system, and a pallet stacking method capable of accurately stacking pallets while suppressing an increase in cost.

A pallet according to an aspect of the present disclosure is a pallet that can be stacked in an up-down direction, in which upper end portions of a plurality of pillars of the pallet disposed in a lower layer are inserted into inserted portions provided in lower end portions of pillars of the pallet disposed in an upper layer. At least one of the pillars has a height higher than the heights of the other pillars. As described above, the pallet has a simple configuration in which the height of at least one of the individual pillars is higher than the height of the other pillars. Therefore, when the pallet is used, the pallet can be stacked with high accuracy while suppressing an increase in cost.

The pallet may include a guide in a lower portion of each of the inserted portions. When the pallet provided in the upper layer is stacked on the pallet provided in the lower layer, the guide portion of the inserted portion of the pallet provided in the upper layer may guide the body portion provided above the guide portion of the inserted portion of the pallet provided in the upper layer to the upper end portions of the columns of the pallet provided in the lower layer. With this configuration, the body portion of the inserted portion of the pallet provided in the upper layer can be easily guided to substantially directly above the support posts of the pallet provided in the lower layer.

In the above pallet, the depth of the inserted portion of the column having a height higher than that of the other columns may be deeper than the depth of the inserted portion of the other columns.

In the above pallet, the difference between the depth of the inserted portion of the leg having a height higher than that of the other leg and the depth of the inserted portion of the other leg may be equal to the difference between the height of the leg having a height higher than that of the other leg and the height of the other leg. As a result, the pallet provided in the upper layer can be stacked on the upper side of the pallet provided in the lower layer while suppressing inclination of the pallet provided in the upper layer with respect to the pallet provided in the lower layer.

In the above-described pallet, the support column may have a polygonal shape or a shape with a rotation stopper. The inner peripheral shape of at least a part of the inserted portion may be larger than the outer peripheral shape of the stay, and may have a polygonal shape corresponding to the outer peripheral shape of the stay, or a shape with a rotation stopper. Here, it is desirable that the polygonal shape has two orthogonal sides. As a result, when the upper end portions of the pillars of the pallet disposed in the lower deck are inserted into the inserted portions of the pallet disposed in the upper deck, for example, both edges of the inserted portions of the pallet disposed in the upper deck contact both edges of the upper end portions of the pillars of the pallet disposed in the lower deck, and therefore, the rotation angle and position of the pallet disposed in the upper deck with respect to the pallet disposed in the lower deck can be accurately defined.

A pallet according to another aspect of the present disclosure is a pallet that can be stacked in an up-down direction, in which upper end portions of a plurality of columns of the pallet disposed in a lower layer are inserted into inserted portions provided in lower end portions of columns of the pallet disposed in an upper layer. The pallet includes a cup portion provided in at least one of the pillars so as to be slidable in a height direction of the pillar. When the pallet is lifted, the cup portion protrudes from the lower end portion of the inserted portion. As mentioned above, the pallet has a simple configuration in which, among the posts, at least one of the posts is provided with a slidable cup portion. Therefore, when the pallet is used, the pallet can be stacked with high accuracy while suppressing an increase in cost.

The pallet may include a guide in a lower portion of each of the inserted portions. When the pallet provided in the upper layer is stacked on the pallet provided in the lower layer, the guide portion of the inserted portion of the pallet provided in the upper layer may guide the body portion provided above the guide portion of the inserted portion of the pallet provided in the upper layer to the upper end portions of the columns of the pallet provided in the lower layer. The cup portion may cover a lower end portion of the guide portion when the pallet disposed in the upper layer is lifted. With this configuration, the body portion of the inserted portion of the pallet provided in the upper layer can be easily guided to substantially directly above the support posts of the pallet provided in the lower layer.

A pallet stacking system according to another aspect of the present disclosure includes: the above pallet; a self-propelled moving body that lifts and lowers a pallet; and a detection unit provided in the moving body to detect the preset pillars in the pallet. Since the above-described pallet having a simple configuration is used, the pallet can be stacked with high accuracy while suppressing an increase in cost.

A pallet stacking method according to another aspect of the present disclosure is a method for stacking pallets, in which upper end portions of a plurality of pillars of a pallet disposed in a lower deck are inserted into inserted portions provided in lower end portions of pillars of a pallet disposed in an upper deck. The pallet stacking method includes: arranging the pallet arranged in the upper deck on an upper side of the pallet arranged in the lower deck, wherein the height of at least one of the pillars is higher than the height of the other pillars; lowering the pallet disposed in the upper deck and inserting the upper end portions of the pillars of the pallet disposed in the lower deck, which are higher in height than the other pillars, into the inserted portions of the pallet disposed in the upper deck; and further lowering the pallet disposed in the upper layer, and inserting the upper end portions of the other columns of the pallet disposed in the lower layer into the inserted portions of the pallet disposed in the upper layer. As described above, since the pallet having a simple configuration in which the height of at least one of the pillars is higher than the heights of the other pillars is used, the pallet can be stacked with high accuracy while suppressing an increase in cost.

A pallet stacking method according to another aspect of the present disclosure is a method for stacking pallets, in which upper end portions of a plurality of pillars of a pallet disposed in a lower deck are inserted into inserted portions provided in lower end portions of pillars of a pallet disposed in an upper deck. The pallet stacking method includes: lifting a pallet provided in the upper layer and having a cup portion provided in at least one of the pillars so as to be slidable in a height direction of the pillar, to protrude the cup portion from a lower end portion of the inserted portion; lowering the pallet disposed in the upper tier and inserting the upper ends of the posts of the pallet disposed in the lower tier into the cups of the pallet disposed in the upper tier; rotating the pallet disposed in the upper layer about upper ends of the posts of the pallet disposed in the lower layer to align the upper ends of the posts of the pallet disposed in the lower layer with the inserted portions of the pallet disposed in the upper layer, wherein the upper ends are inserted into the cups of the pallet disposed in the upper layer; and further lowering the pallet disposed in the upper layer, and inserting the upper end portions of the pillars of the pallet disposed in the lower layer into the inserted portions of the pallet disposed in the upper layer. As described above, since the pallet having a simple configuration in which the cup portions are slidably provided in at least one of the stays is used, the pallet can be stacked with high accuracy while suppressing an increase in cost.

According to the present disclosure, it is possible to realize a pallet, a pallet stacking system, and a pallet stacking method capable of accurately stacking pallets while suppressing an increase in cost.

Drawings

Features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described below with reference to the accompanying drawings, in which like reference numerals represent like elements, and wherein:

fig. 1 is a perspective view showing a pallet according to a first embodiment;

fig. 2 is a schematic view showing a relationship between the height of the upper end portion of the pillar of the pallet provided in the lower layer and the depth of the inserted portion of the pallet provided in the upper layer;

fig. 3A is a schematic diagram showing how pallets are stacked according to the first embodiment;

fig. 3B is a schematic diagram showing how pallets are stacked according to the first embodiment;

fig. 3C is a schematic diagram showing how pallets are stacked according to the first embodiment;

fig. 4A is a schematic view showing how the upper end portions of the pillars of the pallet provided in the lower layer are inserted into the inserted portions of the pallet provided in the upper layer;

fig. 4B is a schematic view showing how the upper end portions of the pillars of the pallet provided in the lower layer are inserted into the inserted portions of the pallet provided in the upper layer;

fig. 4C is a schematic view showing how the upper end portions of the columns of the pallet disposed in the lower layer are inserted into the inserted portions of the pallet disposed in the upper layer;

fig. 4D is a schematic view showing how the upper end portions of the columns of the pallet disposed in the lower layer are inserted into the inserted portions of the pallet disposed in the upper layer;

fig. 5 is a schematic view showing a relationship between a body portion of an inserted portion of a pallet provided in an upper layer and an upper end portion of a stay of the pallet provided in a lower layer;

fig. 6 is a side view showing how the detection unit provided in the moving body detects the upper end portion of the support column in the pallet stacking system according to the second embodiment;

fig. 7 is a plan view showing how the detection unit provided in the moving body detects the upper end portion of the support column in the pallet stacking system according to the second embodiment;

fig. 8 is a block diagram showing a control system of a moving body in the pallet stacking system according to the second embodiment;

FIG. 9 is a schematic view for illustrating the position of the center of gravity of the upper end portion of the stay;

fig. 10A is a schematic diagram showing how pallets are stacked according to a third embodiment;

fig. 10B is a schematic view showing how pallets are stacked according to the third embodiment;

fig. 10C is a schematic view showing how pallets are stacked according to the third embodiment;

fig. 10D is a schematic diagram showing how pallets are stacked according to the third embodiment;

fig. 11A is a schematic view showing how the upper end portions of the pillars of the pallet provided in the lower layer are inserted into the inserted portions of the pallet provided in the upper layer;

fig. 11B is a schematic view showing how the upper end portions of the pillars of the pallet provided in the lower layer are inserted into the inserted portions of the pallet provided in the upper layer;

fig. 11C is a schematic view showing how the upper end portions of the pillars of the pallet provided in the lower layer are inserted into the inserted portions of the pallet provided in the upper layer; and is

Fig. 11D is a schematic view showing how the upper end portions of the pillars of the pallet provided in the lower layer are inserted into the inserted portions of the pallet provided in the upper layer.

Detailed Description

Hereinafter, specific embodiments to which the present disclosure is applied will be described in detail with reference to the accompanying drawings. However, the present disclosure is not limited to the following embodiments. The following description and drawings are simplified as appropriate for the sake of clarity.

First embodiment

First, the configuration of the pallet according to the present embodiment will be described. The following description is based on a state in which the pallet is placed on a horizontal surface. In addition, the following description is made based on the up-down direction, the front-back direction, and the left-right direction shown in fig. 1, but the front-back direction and the left-right direction may be appropriately replaced with each other depending on the arrangement of the pallet.

Fig. 1 is a perspective view showing a pallet according to the present embodiment. Fig. 2 is a schematic view showing a relationship between the height of the upper end portion of the pillar of the pallet provided in the lower layer and the depth of the inserted portion provided in the lower end portion of the pillar of the pallet provided in the upper layer.

For example, the pallet 1 of the present embodiment is suitable for stacking and arranging workpieces in facilities such as warehouses. The pallet 1 has a configuration in which the upper end portions of the columns 2 of the pallet (hereinafter may be referred to as a second pallet 12) disposed in the lower deck are inserted into the inserted portions 4 provided in the lower end portions of the columns 2 of the pallet (hereinafter may be referred to as a first pallet 11) disposed in the upper deck, so that the pallets 1 can be stacked in the up-down direction (see fig. 3C).

Specifically, as shown in fig. 1, the pallet 1 includes columns 2, beams 3, and inserted portions 4, and the pallet 1 is assembled into a rectangular frame structure, for example, when viewed from the up-down direction. However, the shape of the pallet 1 is not limited to a rectangular shape when viewed in the up-down direction, and may be a circular shape, an elliptical shape, or a polygonal shape.

The pillars 2 extend in the up-down direction, and are provided at the corners of the pallet 1 when viewed in the up-down direction. Among the pillars 2, at least one pillar 2 (hereinafter may be referred to as a first pillar 21) has a height higher than that of the other pillars 2 (hereinafter may be referred to as a second pillar 22). Accordingly, the first leg 21 protrudes further upward by a height H1 relative to the second leg 22.

Height H1 is preferably set in the range of 1% to 20% of the diagonal length L1 of pallet 1. Specifically, for example, when the diagonal length L1 of the pallet 1 is 1000mm (millimeters), the height H1 is preferably set in the range of 10mm to 200 mm. The reason for setting the height H1 within the above range will be described later.

The first strut 21 is preferably a rectangular strut with two adjacent sides generally orthogonal to each other. Preferably, one pair of opposite sides of the first stay 21 extend substantially in the left-right direction, and the other pair of opposite sides of the first stay 21 extend substantially in the front-rear direction. Further, as shown in fig. 2, the upper end portion of the first stay 21 is preferably provided with a tapered portion 2a that narrows toward the upper side of the first stay 21.

However, although a detailed function will be described later, the outer peripheral shape of the upper end portion of the first stay 21 is preferably a polygonal shape or a shape with a rotation stopper. The outer circumferential shape of the second support columns 22 is not limited, but if they are the same as the outer circumferential shape of the first support columns 21, the pallet 1 may be manufactured using the same members as the first support columns 21. In order to reduce weight, the pillar 2 preferably has a hollow structure. Here, the "rotation stopper" refers to a portion provided to restrict rotation of the first pallet 11 when the upper end portion of the first support column 21 of the second pallet 12 is inserted into the inserted portion 4 of the first support column 21 of the first pallet 11, which will be described later.

The cross beam 3 connects the lower portions of the adjacent pillars 2. In this case, in order to be able to insert the forks 5a of the forklift 5 between the crossmember 3 and the facility floor (see fig. 3A), the height between the lower end portion of the crossmember 3 and the lower end portion of the pallet 1 is set to be higher than the height of the forks 5a of the forklift 5.

An inserted portion 4 is provided at a lower end portion of each of the columns 2, and when the first pallet 11 is stacked on an upper side of the second pallet 12, an upper end portion of the column 2 of the second pallet 12 is inserted into the inserted portion 4 of the first pallet 11. As shown in fig. 2, the inserted portion 4 has a tubular shape having a bottom portion 4a at an upper end portion of the inserted portion 4, and an inner peripheral shape of the inserted portion 4 corresponds to an outer peripheral shape of an upper end portion of the stay 2.

For example, the inner peripheral shape of at least a part of the inserted portion 4 provided in the first support column 21 is preferably a rectangular shape slightly larger than the outer peripheral shape of the upper end portion of the first support column 21. The inner peripheral shape of the inserted portion 4 provided in the second pillar 22 is preferably slightly larger than the outer peripheral shape of the upper end portion of the second pillar 22.

The depth of the inserted portion 4 provided in the first support column 21 is deeper than the depth of the inserted portion 4 provided in the lower end portion of the second support column 22 by a height H1. That is, the depth of the inserted portion 4 of the first support column 21 is deeper than the depth of the inserted portion 4 of the second support column 22 by a height H1, and this height H1 is a height at which the first support column 21 protrudes further upward with respect to the second support column 22.

As shown in fig. 2, it is preferable that the guide portion 4b is provided in a lower portion of the inserted portion 4. The guide 4b guides the body portion 4c provided above the guide 4b in the inserted portion 4 of the first pallet 11 to the upper end portion of the pillar 2 of the second pallet 12.

The inner peripheral shape of the guide portion 4b is an inverted bowl-like shape that narrows toward the upper side of the guide portion 4b, and the upper end portion of the inner peripheral surface of the guide portion 4b is substantially continuous with the lower end portion of the inner peripheral surface of the body portion 4 c. That is, the inserted portion 4 of the present embodiment includes a guide portion 4b having an inverted bowl-shaped inner peripheral surface, and a body portion 4c provided above the guide portion 4b and having a rectangular inner peripheral surface.

Here, as shown in fig. 2, the relationship between the length L2 of one side of the stay 2 and the length L3 of one side of the lower opening of the guide portion 4b (for example, the short-axis direction length of the inner peripheral edge of the lower end in the lower opening of the guide portion 4 b) preferably satisfies < equation 1 >.

< equation 1>1.2 × L2< L3<5 × L2

Further, it is preferable that the height H1 and the height of the guide 4b be set to a height at which the upper end of the second support column 22 of the second pallet 12 is inserted into the guide 4b of the inserted portion 4 provided in the second support column 22 of the first pallet 11 when the upper end of the first support column 21 of the second pallet 12 is inserted into the body portion 4c of the inserted portion 4 provided on the first support column 21 of the first pallet 11 by about 10mm or more.

Next, the flow of stacking the pallet 1 will be described using the pallet 1 of the present embodiment. Here, in the present embodiment, it is assumed that the operator operates the forklift 5 to stack the pallet 1. Fig. 3A to 3C are schematic views showing how pallets according to the present embodiment are stacked. In fig. 3B and 3C, the forklift is omitted for clarity of movement of the pallet.

First, as shown in fig. 3A, the forks 5a of the forklift 5 are inserted between the floor and the cross beams 3 of the first pallet 11 placed on the facility floor, and the first pallet 11 is lifted by the forklift 5. At this time, the first pallet 11 is lifted in a state where the position of the first support column 21 of the first pallet 11 is aligned with the position of the first support column 21 of the second pallet 12 placed on the facility floor in advance (the front right side in fig. 3B).

The forklift 5 then places the first pallet 11 on the upper side of the second pallet 12. At this time, the first pallet 11 is placed on the second pallet 12 such that the first support column 21 of the second pallet 12 is disposed substantially directly below the first support column 21 of the first pallet 11 and the second support column 22 of the second pallet 12 is disposed substantially directly below the second support column 22 of the first pallet 11.

Next, as shown in fig. 3B, the forklift 5 lowers the first pallet 11, and inserts the upper end portion of the first pillar 21 of the second pallet 12 into the inserted portion 4 provided in the first pillar 21 of the first pallet 11.

Fig. 4A to 4D are schematic views showing how the upper end portion of the first support column of the second pallet is inserted into the inserted portion provided in the first support column of the first pallet. Specifically, as shown in fig. 4A, the first pallet 11 is lowered so that the upper end portion of the first support column 21 of the second pallet 12 is inserted into the guide portion 4b of the inserted portion 4 provided in the first support column 21 of the first pallet 11.

Then, as shown in fig. 4B, the upper end portion of the first support column 21 of the second pallet 12 is inserted into the guide portion 4B of the inserted portion 4 provided in the first support column 21 of the first pallet 11. At this time, the guide 4b of the first pallet 11 has an inverted bowl shape.

Accordingly, the position of the first pallet 11 relative to the second pallet 12 is corrected so that the body portion 4c of the inserted portion 4 provided in the first support column 21 of the first pallet 11 is provided substantially directly above the first support column 21 of the second pallet 12 while the inner peripheral surface of the guide portion 4b of the first pallet 11 contacts the upper end portion of the first support column 21 of the second pallet 12.

Here, when the relationship between the length L2 of one side of the pillar 2 and the length L3 of one side of the lower opening of the guide 4b is L3 ≦ 1.2 × L2, it is difficult to insert the upper end portion of the first pillar 21 of the second pallet 12 into the guide 4b of the inserted portion 4 provided in the first pillar 21 of the first pallet 11, and when the relationship between L2 and L3 is L3 ≧ 5 × L2, the ability to correct the position of the first pallet 11 is reduced.

Then, the first pallet 11 is further lowered in a state where the main body portion 4c of the inserted portion 4 provided in the first support column 21 of the first pallet 11 is provided substantially directly above the first support column 21 of the second pallet 12. Therefore, as shown in fig. 4C, the upper end portion of the first support column 21 of the second pallet 12 is inserted into the body portion 4C of the inserted portion 4 provided in the first support column 21 of the first pallet 11.

At this time, when the first support column 21 of the second pallet 12 is a rectangular support column, and the inner peripheral shape of the body portion 4c of the inserted portion 4 provided in the first support column 21 of the first pallet 11 is a rectangular shape, the rotation angle and position of the first pallet 11 are defined. Fig. 5 is a schematic view showing a relationship between a body portion of an inserted portion provided in a first pillar of a first pallet and an upper end portion of the first pillar of a second pallet.

Specifically, in the case where the first support column 21 of the second pallet 12 is a rectangular support column and the inner peripheral shape of the body portion 4c of the inserted portion 4 provided in the first support column 21 of the first pallet 11 is a rectangular shape, as shown in fig. 5, when the upper end portion of the first support column 21 of the second pallet 12 is inserted into the body portion 4c of the inserted portion 4 provided in the first support column 21 of the first pallet 11, two adjacent sides of the body portion 4c of the inserted portion 4 of the first pallet 11 come into contact with two adjacent sides of the upper end portion of the first support column 21 of the second pallet 12, thereby defining the rotation angle and position of the first pallet 11 with respect to the second pallet 12.

That is, the front-rear direction and the left-right direction of the first pallet 11 with respect to the second pallet 12 are defined. As a result, even if the rotation angle and position of the first pallet 11 with respect to the second pallet 12 are slightly deviated, the inserted portion 4 provided in the second support column 22 of the first pallet 11 can be accurately provided substantially directly above the second support column 22 of the second pallet 12.

Here, when the height H1 is less than 1% of the diagonal length L1 of the pallet 1, the ability to define the rotation angle and position of the first pallet 11 is poor. The height H1 need not be greater than 20% of the diagonal length L1 of the pallet 1, in view of the ability to define the angle of rotation and the position of the first pallet 11.

Subsequently, in a state where the inserted portion 4 of the first pallet 11 is disposed substantially directly above the support posts 2 of the second pallet 12, as shown in fig. 3C, the first pallet 11 is further lowered. As a result, the upper end portions of the posts 2 of the second pallet 12 are inserted into the inserted portions 4 of the first pallet 11.

Here, in the case where the height H1 and the height of the guide 4b are set to such heights (where the upper end of the second support column 22 of the second pallet 12 is inserted into the guide 4b of the inserted portion 4 provided in the second support column 22 of the first pallet 11 when the upper end of the first support column 21 of the first pallet 11 is inserted into the body portion 4c of the inserted portion 4 provided in the first support column 21 of the second pallet 12 by about 10mm or more), the inserted portion 4 provided in the second support column 22 of the first pallet 11 can be accurately provided substantially directly above the second support column 22 of the second pallet 12, and then the upper end of the support column 2 of the second pallet 12 can be inserted into the inserted portion 4 of the first pallet 11.

Subsequently, the first pallet 11 is further lowered, and as shown in fig. 4D, the upper end portion of the first support column 21 of the second pallet 12 is brought into contact with the bottom portion 4a of the inserted portion 4 provided in the first support column 21 of the first pallet 11. Similarly, the upper end portion of the second support column 22 of the second pallet 12 is brought into contact with the bottom portion 4a of the inserted portion 4 provided in the second support column 22 of the first pallet 11. As a result, the first pallet 11 is stacked on the upper side of the columns 2 of the second pallet 12.

At this time, as described above, since the inserted portion 4 of the first pallet 11 is accurately disposed substantially directly above the support column 2 of the second pallet 12, the upper end portion of the second support column 22 of the second pallet 12 can be easily inserted into the inserted portion 4 provided in the second support column 22 of the first pallet 11 only by lowering the first pallet 11, and further, the first pallet 11 can be accurately stacked on the upper side of the second pallet 12.

Further, since the depth of the inserted portion 4 provided in the lower end portion of the first support column 21 is deeper than the depth of the inserted portion 4 provided in the lower end portion of the second support column 22 by the height H1, the first pallet 11 can be stacked on the upper side of the second pallet 12 while suppressing the inclination of the first pallet 11 with respect to the second pallet 12.

As described above, the pallet 1 of the present embodiment has a simple configuration in which, of the pillars 2, the height of at least one of the pillars 2 is higher than the heights of the other pillars 2. Therefore, when the pallet 1 of the present embodiment is used, the pallet 1 can be stacked with high accuracy while suppressing an increase in cost.

Here, when the outer peripheral shape of the upper end portion of the first support column 21 and the inner peripheral shape of the body portion 4c of the inserted portion 4 provided in the first support column 21 are not rectangular shapes as described above, for example, by rotating the first pallet 11 around the upper end portion of the first support column 21 of the second pallet 12, the inserted portion 4 provided in the second support column 22 of the first pallet 11 can be easily provided substantially directly above the second support column 22 of the second pallet 12.

Moreover, since the guide portion 4b is provided in the lower portion of the inserted portion 4, the body portion 4c of the inserted portion 4 of the first pallet 11 can be easily guided to substantially directly above the support posts 2 of the second pallet 12.

Further, when the outer peripheral shape of the upper end portion of the first support column 21 and the inner peripheral shape of the body portion 4c of the inserted portion 4 provided in the first support column 21 are rectangular shapes, by inserting the upper end portion of the first support column 21 of the second pallet 12 into the body portion 4c of the inserted portion 4 provided in the first support column 21 of the first pallet 11, the inserted portion 4 provided in the second support column 22 of the first pallet 11 can be accurately provided substantially directly above the second support column 22 of the second pallet 12.

Therefore, the upper end portion of the second support column 22 of the second pallet 12 can be easily inserted into the inserted portion 4 provided in the second support column 22 of the first pallet 11, and further, the first pallet 11 can be accurately stacked on the upper side of the second pallet 12.

Second embodiment

In the first embodiment, the operator operates the forklift 5 to stack the pallet 1, but the pallet 1 may be stacked using a self-propelled moving body. First, the configuration of the stacking system 31 of the pallet 1 according to the present embodiment will be described.

Fig. 6 is a side view showing how the detection unit provided in the moving body detects the upper end portion of the first support column in the pallet stacking system according to the present embodiment. Fig. 7 is a plan view showing how the detection unit provided in the moving body detects the upper end portion of the first support column in the pallet stacking system according to the present embodiment. Fig. 8 is a block diagram showing a control system of a moving body in the pallet stacking system according to the present embodiment. Note that, in fig. 6 and 7, the laser beam emitted from the detection unit is shown by a long double short dashed line. Further, in fig. 7, a hatched portion indicates the detection range of the detection unit.

In the present embodiment, as shown in fig. 6 and 7, the stacking system 31 is constituted by the pallet 1 and the moving body 41 of the first embodiment. The moving body 41 is a self-propelled forklift. Specifically, as shown in fig. 6 and 7, the moving body 41 includes a chassis 42, a mast 43 provided in front of the chassis 42, forks 44 that can be raised and lowered in the up-down direction along the mast 43, drive wheels 45 and steering wheels 46 provided in the chassis 42, a detection unit 47, and a control unit 48.

The detection unit 47 detects the first support column 21 as the preset support column 2 of the pallet 1. The detection unit 47 includes, for example, a laser ranging sensor, and is fixed to the moving body 41 so as to detect the upper end portion of the first support column 21 of the pallet 1 placed on the facility floor, and not to detect the upper end portion of the second support column 22, as shown in fig. 6 to 8. The detection unit 47 is not limited to the laser distance sensor, and may be a general photosensor.

Here, as shown in fig. 7, the detection unit 47 of the present embodiment has a detection area so that all the columns 2 of the pallet 1 can be substantially covered within the detection area when the pallet 1 is viewed in the up-down direction. However, the detection unit 47 only needs to have a detection area capable of covering at least one of the columns 2 of the pallet 1 within the detection area.

The control unit 48 controls a motor 49, a motor 50, and a motor 51, while referring to the detection result of the detection unit 47, wherein the motor 49 is used to raise and lower the fork 44 shown in fig. 7, the motor 50 is used to drive the driving wheels 45, and the motor 51 is used to manipulate the steering wheels 46, so that the moving body 41 moves along the preset path and stacks the pallet 1.

Further, the control unit 48 calculates, for example, coordinates of the center of gravity position in the front-rear direction and the left-right direction of the first support column 21 with the preset position of the moving body 41 serving as the origin, and the rotation angle of the pallet 1 around the axis passing through the center of gravity position of the first support column 21 and extending in the up-down direction, based on the detection result of the detection unit 47. The coordinates of the first support column 21 and the rotation angle of the pallet 1 in the horizontal plane are preferably calculated as the position of the first support column 21. Further, the origin may be a point other than the center of gravity as long as it can be calculated from the position of the first pillar 21, and may be any one point of, for example, four corners of the pillar.

Here, it is preferable that the control unit 48 is constituted by a computer including a Central Processing Unit (CPU), and the control unit 48 executes a program to realize a stacking process of the pallet 1 described later.

The above-described program is stored using various types of non-transitory computer-readable media, and may be provided to a computer (a computer including an information notification apparatus). Non-transitory computer readable media include various types of tangible storage media. Examples of non-transitory computer readable media include magnetic recording media (e.g., floppy disks, magnetic tapes, hard disk drives) and magneto-optical recording media (e.g., magneto-optical disks). Further, examples include Compact Disk (CD) Read Only Memory (ROM), CD-R, and CD-R/W. Further, examples include semiconductor memories (e.g., mask ROM, PROM, EPROM, flash ROM, RAM). The program may be supplied to the computer through various types of transitory computer-readable media. Examples of transitory computer readable media include electrical signals, optical signals, and electromagnetic waves. The transitory computer-readable medium may supply the program to the computer via a wired communication path such as an electric wire and an optical fiber or a wireless communication path.

Next, a flow of stacking the pallet 1 using the stacking system 31 of the present embodiment will be described. First, the control unit 48 of the moving body 41 controls the motors 50 and 51 to cause the moving body 41 to travel on the facility floor so that the moving body 41 is disposed in front of the first pallet 11 placed on the facility floor.

Next, the control unit 48 of the moving body 41 calculates the coordinates of the upper end portions of the first supports 21 of the first pallet 11 and the rotation angle of the first pallet 11 based on the detection result of the detection unit 47. Here, as shown in fig. 9, when the first support column 21 is a rectangular support column and the pallet 1 is rotated, there is a case where the adjacent corner portions of the first support column 21 cannot be detected by the detection unit 47, and therefore the coordinates of the upper end portion of the first support column 21 cannot be accurately calculated.

At this time, when the first stay 21 is a rectangular stay and a position at half of the length L2 along one side of the first stay 21 from the detected corner of the first stay 21 is defined as a point P1, the position G of the center of gravity of the first stay 21 is provided at a position at half of the length L2 from the point P1 in the normal direction with respect to the one side.

Therefore, the control unit 48 may calculate the coordinates of the first support column 21 based on the coordinates of the corner detected in the first support column 21, the preset length L2 of the side of the first support column 21, and the rotation angle of the first pallet 11.

In this way, even if the first pallet 11 is rotated and placed with respect to the moving body 41, the coordinates of the first support column 21 can be accurately calculated. The rotation angle of the first pallet 11 can be calculated based on the inclination of the one side of the first pillar 21 with respect to the axis extending in the left-right direction.

Next, the control unit 48 of the moving body 41 controls the motors 49, 50, and 51 so that the moving body 41 approaches the first pallet 11 and lifts the first pallet 11 with the forks 44. At this time, the moving body 41 stores the coordinates of the upper end portion of the first pillar 21 of the first pallet 11 and the rotation angle of the first pallet 11 immediately before lifting the first pallet 11. Then, in a state where the first pallet 11 is lifted, the control unit 48 controls the motors 50 and 51 so that the moving body 41 is disposed in front of the second pallet 12 previously placed on the facility floor.

Next, the control unit 48 of the moving body 41 calculates the coordinates of the upper end portion of the first support column 21 of the second pallet 12 and the rotation angle of the second pallet 12 based on the detection result of the detection unit 47. Then, the control unit 48 compares the coordinates of the first support column 21 of the first pallet 11 and the rotation angle of the first pallet 11 with the coordinates of the first support column 21 of the second pallet 12 and the rotation angle of the second pallet 12, and controls the motors 50 and 51 so as to approximately match each other. As a result, the inserted portion 4 of the first pallet 11 is disposed substantially directly above the support posts 2 of the second pallet 12.

Subsequently, the control unit 48 of the moving body 41 controls the motor 49 to lower the first pallet 11 by the forks 44 of the moving body 41 so that the upper end portion of the first support column 21 of the second pallet 12 is inserted into the inserted portion 4 provided in the first support column 21 of the first pallet 11.

Therefore, the upper end portion of the first support column 21 of the second pallet 12 is inserted into the inserted portion 4 provided in the first support column 21 of the first pallet 11, and the first pallet 11 is accurately provided on the upper side of the second pallet 12 as described in the first embodiment.

Subsequently, the control unit 48 of the moving body 41 controls the motor 49 to lower the first pallet 11 by the forks 44 of the moving body 41. Therefore, the upper end portion of the second support column 22 of the second pallet 12 is inserted into the inserted portion 4 provided in the second support column 22 of the first pallet 11, and the first pallet 11 is stacked on the upper side of the second pallet 12.

As described above, also in the present embodiment, since the pallet 1 having a simple configuration in which the height of at least one of the pillars 2 is higher than the height of the other pillars 2 is used, the pallet 1 can be stacked with high accuracy while suppressing an increase in cost. Also, it is not necessary to provide a plurality of detection units to calculate the coordinates of the support columns 2 and the rotation angle of the pallet 1, and therefore the pallet 1 can be stacked with high accuracy while suppressing an increase in cost.

Here, the moving body 41 is preferably provided with a detection unit for detecting that the pallet 1 is placed on the forks 44. In this way, the control unit 48 can accurately recognize that the first pallet 11 is stacked on the second pallet 12.

Third embodiment

Fig. 10A to 10D are schematic views showing how pallets according to the present embodiment are stacked. Fig. 11A to 11D are schematic views showing how the upper end portions of the pillars of the second pallet are inserted into the inserted portions of the first pallet.

The pallet 6 in the present embodiment also has a configuration in which the upper end portions of the columns 7 of the pallet (hereinafter may be referred to as a second pallet 62) provided in the lower layer as shown in fig. 10D or the like are inserted into the inserted portions 9 provided in the lower end portions of the columns 7 of the pallet (hereinafter may be referred to as a first pallet 61) provided in the upper layer, so that the pallets 6 can be stacked in the up-down direction.

Specifically, as shown in fig. 10A and the like, the pallet 6 includes the pillars 7, the beams 8, the inserted portions 9, and the cup portions 10, and for example, the pallet 6 is assembled into a rectangular frame structure when viewed in the up-down direction. However, the shape of the pallet 6 is not limited to a rectangular shape when viewed in the up-down direction, and may be a circular shape, an elliptical shape, or a polygonal shape.

The pillars 7 extend in the up-down direction, and are provided such that the upper end portions of the pillars 7 are positioned substantially at the same height. For example, all the struts 7 are struts having substantially the same length. Further, as shown in fig. 11A and the like, the upper end portion of the stay 7 is preferably provided with a tapered portion 7a that narrows toward the upper side of the stay 7. For weight saving, the stay 7 preferably has a hollow structure.

The cross beam 8 connects the lower portions of the adjacent pillars 7. In this case, in order to be able to insert the forks of the forklift between the crossmember 8 and the facility floor, the height between the lower end portion of the crossmember 8 and the lower end portion of the pallet 6 is set to be higher than the height of the forks of the forklift.

An inserted portion 9 is provided at a lower end portion of each of the support columns 7, and when the first pallet 61 is stacked on the upper side of the second pallet 62, an upper end portion of the support column 7 of the second pallet 62 is inserted into the inserted portion 9 of the first pallet 61.

As shown in fig. 11A and the like, the inserted portion 9 has a tubular shape having a bottom portion 9a at an upper end portion of the inserted portion 9, and an inner peripheral shape of the inserted portion 9 corresponds to an outer peripheral shape of an upper end portion of the stay 7. For example, the inner peripheral shape of the inserted portion 9 is preferably slightly larger than the outer peripheral shape of the upper end portion of the stay 7. The depth of each inserted portion 9 is substantially the same.

Here, as shown in fig. 11A and the like, it is preferable that the guide portion 9b is provided in a lower portion of the inserted portion 9. The guide portion 9b guides the main body portion 9c provided above the guide portion 9b in the inserted portion 9 of the first pallet 61 to the upper end portion of the support column 7 of the second pallet 62.

The inner peripheral shape of the guide portion 9b is an inverted bowl-like shape that narrows toward the upper side of the guide portion 9b, and the upper end portion of the inner peripheral surface of the guide portion 9b is substantially continuous with the lower end portion of the inner peripheral surface of the main body portion 9c of the inserted portion 9. That is, the inserted portion 9 of the present embodiment includes a guide portion 9b having an inner peripheral surface of an inverted bowl shape, and a body portion 9c provided above the guide portion 9b and having an inner peripheral surface corresponding to an outer peripheral surface of an upper end portion of the stay 7.

The cup portion 10 is provided in at least one of these support posts 7 so as to be slidable in the up-down direction with respect to the support post 7. The cup portion 10 has an inverted bowl-like shape having an opening 10a at an upper end of the cup portion 10, and the body portion 9c of the inserted portion 9 passes through the inside of the opening 10 a.

As shown in fig. 10A, when the pallet 6 is placed on the facility floor, the cup 10 slides upward along the body portion 9c of the inserted portion 9 so that the lower end portion of the inserted portion 9 and the lower end portion of the cup 10 are disposed at substantially the same height.

As shown in fig. 10B, when the pallet 6 is lifted, the cup 10 slides to the lower side along the body portion 9c of the inserted portion 9, and the lower portion of the cup 10 protrudes from the lower end portion of the inserted portion 9 in a state where the peripheral edge of the opening 10a of the cup 10 is hooked on the guide portion 9B of the inserted portion 9. At this time, the cup 10 covers the inserted portion 9. Here, the inner peripheral surface of the cup 10 and the lower end portion of the guide portion 9b of the inserted portion 9 are preferably provided to be substantially continuous.

Next, a flow of stacking the pallet 6 using the pallet 6 of the present embodiment will be described. Here, in the present embodiment, it is assumed that the operator operates the forklift to stack the pallet 6.

First, from a state in which the first pallet 61 is placed on the facility floor (as shown in fig. 10A), the forks of the forklift are inserted between the crossbeams 8 of the first pallet 61 and the floor, and the first pallet 61 is lifted by the forklift, as shown in fig. 10B.

Therefore, the cup 10 slides to the lower side along the body portion 9c of the inserted portion 9, and the lower portion of the cup 10 protrudes from the lower end portion of the inserted portion 9 in a state where the peripheral edge of the opening 10a of the cup 10 is hooked on the guide portion 9b of the inserted portion 9.

The forklift then places the first pallet 61 on the upper side of the second pallet 62. At this time, the first pallet 61 is placed on the second pallet 62 such that the columns 7 of the second pallet 62 are disposed substantially directly below the columns 7 of the first pallet 61.

Next, as shown in fig. 10C, the forklift lowers the first pallet 61 and inserts the upper end portions of the support columns 7 of the second pallet 62 into the cup 10, the inserted portion 9 of the first pallet 61 passing through the cup 10.

Specifically, as shown in fig. 11A, the first pallet 61 is lowered so that the upper end portions of the pillars 7 of the second pallet 62 are inserted into the cup 10, and the inserted portion 9 of the first pallet 61 passes through the cup 10.

Then, as shown in fig. 11B, the forklift further lowers the first pallet 61. In this way, the position of the first pallet 61 relative to the second pallet 62 is corrected such that the guide portions 9b of the inserted portions 9 of the first pallet 61 are disposed substantially directly above the posts 7 of the second pallet 62 while the inner peripheral surface of the cup portions 10 of the first pallet 61 through which the inserted portions 9 pass contacts the upper end portions of the posts 7 of the second pallet 62.

Then, the position of the first pallet 61 is adjusted using a forklift so that the guide portions 9b of the remaining inserted portions 9 of the first pallet 61 are disposed substantially directly above the posts 7 of the second pallet 62 in a state where the guide portions 9b provided in the inserted portions 9 of the first pallet 61 are disposed substantially directly above the posts 7 of the second pallet 62.

At this time, when the first pallet 61 is rotated around the upper end portions of the pillars 7 of the second pallet 62 inserted into the cups 10 of the first pallet 61, the position of the first pallet 61 can be adjusted with relatively high accuracy.

The first pallet 61 is further lowered to insert the columns 7 of the second pallet 62 into the guides 9b of the inserted portions 9 of the first pallet 61. At this time, the guide portion 9b of the first pallet 61 has an inverted bowl shape.

Accordingly, the position of the first pallet 61 relative to the second pallet 62 is corrected such that the body portion 9c of the inserted portion 9 of the first pallet 61 is disposed substantially directly above the support posts 7 of the second pallet 62 while the inner peripheral surface of the guide portion 9b of the first pallet 61 contacts the upper end portions of the support posts 7 of the second pallet 62. Here, when the inner peripheral surface of the cup 10 and the lower end portion of the guide portion 9b of the inserted portion 9 are provided to be substantially continuous, the position of the first pallet 61 can be smoothly corrected.

Next, in a state where the main body portion 9C of the inserted portion 9 of the first pallet 61 is disposed substantially directly above the support posts 7 of the second pallet 62, the first pallet 61 is further lowered, and as shown in fig. 11C, the upper end portions of the support posts 7 of the second pallet 12 are inserted into the main body portion 9C of the inserted portion 9 of the first pallet 61.

In this case, although not shown, when a part of the cup 10 protrudes from the inserted portion 9, as shown in fig. 11C and the like, the cup 10 may slide upward when the stays 7 of the second pallet 12 are inserted into the body portion 9C of the inserted portion 9 of the first pallet 61.

Subsequently, as shown in fig. 10D and 11D, the first pallet 61 is further lowered, and the upper end portions of the columns 7 of the second pallet 62 are brought into contact with the bottom portions 9a of the inserted portions 9 of the first pallet 61. As a result, the first pallet 61 is stacked on the upper side of the columns 7 of the second pallet 62.

As described above, the pallet 6 of the present embodiment has a simple configuration in which, among the stays 7, at least one of the stays 7 is provided with the slidable cup portion 10. Therefore, when the pallet 6 of the present embodiment is used, the pallet 6 can be stacked with high accuracy while suppressing an increase in cost.

In the present embodiment, the operator operates the forklift to stack the pallets 6, but the pallets 6 may be stacked using the self-propelled moving body as in the second embodiment. At this time, the detection unit of the moving body preferably detects, for example, the position of the support post 7 on the right front side of the pallet 6 (as the preset support post 7 of the pallet 6 placed on the facility floor), and then the moving body preferably performs the flow of stacking the pallet 6 of the third embodiment. The detection unit only needs to detect the position of at least one of these pillars 7.

The present disclosure is not limited to the above-described embodiments, and may be modified as appropriate without departing from the spirit thereof.

For example, in the case where the pillars 2 of the first and second embodiments are configured to have a cylindrical shape, when the height of at least two pillars 2 is configured to be higher than the height of the other pillars 2, when the first pallet 11 is stacked on the upper side of the second pallet 12, the position of the first pallet 11 with respect to the second pallet 12 can be corrected.

Further, in the case where the pillars 2 of the first and second embodiments are configured to have an oval shape, as in the first and second embodiments, when the height of at least one pillar 2 is configured to be higher than the height of the other pillars 2, when the first pallet 11 is stacked on the upper side of the second pallet 12, the position of the first pallet 11 with respect to the second pallet 12 can be corrected.

For example, in the first and second embodiments, the configuration is such that the difference between the depth of the inserted portion 4 provided in the first support column 21 and the depth of the inserted portion 4 provided in the second support column 22 in the pallet 1 is substantially equal to the difference H1 between the height of the first support column 21 and the height of the second support column 22. However, it is only necessary to suppress the inclination of the first pallet 11 while the first pallet 11 can be stacked on the upper side of the second pallet 12, and the configuration may be such that a stopper or the like is provided inside the inserted portion 4 provided in the first support column 21 so that the upper end portion of the first support column 21 of the second pallet 12 is inserted by no more than a preset depth.