JP7720132B2 - Pallet for packing glass plates, glass plate package, and method for manufacturing glass plate package - Google Patents

Description

The present invention relates to a pallet for packaging glass plates, a glass plate package, and a method for manufacturing a glass plate package.

Glass plate packaging pallets are used when storing or transporting various types of glass plates, including glass substrates for flat panel displays such as liquid crystal displays.

The basic structure of this type of pallet comprises a base section on top of which is housed a glass plate laminate, which is made up of multiple glass plates stacked in a vertical position with protective sheets (such as interleaf paper) between them, a back support section that supports the back side of the glass plate laminate, and a bottom support section that supports the bottom side of the glass plate laminate.

For example, Patent Document 1 discloses that the bottom support portion is equipped with a resin sheet material as a cushioning material to prevent the glass plate from being damaged by impact or vibration. The same document also discloses that a low-friction sheet material is placed on top of the resin sheet material as a cover member to improve the sliding properties of the bottom edge of the glass plate.

Japanese Patent Application Laid-Open No. 2017-65726

Patent Document 1 does not disclose the specific arrangement of the resin sheet material as a cushioning material and the low-friction sheet material as a cover member in the direction along the bottom edge of the glass plate. However, if the cushioning material and cover member are each arranged along the entire length of the bottom edge of the glass plate, the following problems may arise.

In other words, the cover member is supported from below by the buffer material at positions corresponding to the corners formed at both ends of the bottom edge of the glass plate. Therefore, when loading glass plates, if the corners of the bottom edge of the glass plate press the cover member downward due to gravity, the cover member is likely to be subjected to a reaction force from the buffer material and bite into the corners of the glass plate. As a result, the corners of the glass plate get caught on the cover member, preventing the glass plate from moving to the correct position, and gaps are likely to form between the glass plates. Such gaps between the glass plates not only reduce the loading efficiency of the glass plates but also pose the risk of damage such as cracking of the glass plates. While Patent Document 1 discloses the use of low-friction sheet material as the cover member, the corners of the glass plate getting caught can be primarily caused by the arrangement of the buffer material and the cover member, i.e., structural issues. Therefore, it is believed that it is difficult to reduce the gaps between the glass plates that occur when the corners of the glass plate get caught using a material approach alone.

The present invention aims to provide a pallet for packaging glass plates, a glass plate package, and a method for manufacturing a glass plate package that can reduce gaps between glass plates when loading the glass plates.

The glass plate packing pallet of the present invention, which was invented to solve the above-mentioned problems, is a glass plate packing pallet comprising a base portion on which a glass plate laminate including glass plates and a protective sheet is stored in a vertical position, a back support portion supporting the back surface of the glass plate laminate, and a bottom support portion supporting the bottom edge of the glass plate laminate. The bottom support portion comprises an intervening member between the base portion and the glass plate laminate, and a cover member arranged above the intervening member, the cover member being arranged over the entire length of the bottom edge of the glass plate, and at least a portion of the intervening member being arranged only in the middle of the bottom edge of the glass plate.

In this way, a space where no intervening member is placed is formed below the cover member at a position corresponding to the corners formed at both ends of the bottom edge of the glass plate. Therefore, even if the corners of the bottom edge of the glass plate press the cover member downward due to gravity, the cover member can deform and retreat downward, utilizing the space where no intervening member is placed. This makes it less likely for the corners to get caught when the glass plates are stacked, reducing the formation of gaps between the glass plates.

In the above configuration, it is preferable that the interposing member is made of a laminate of multiple components, and that at least some of the components are arranged only in the middle of the bottom edge of the glass plate.

In this way, even if the interposing member is made up of a laminate of multiple components, the corners are less likely to get caught when the glass plates are stacked, reducing the formation of gaps between the glass plates.

In the above configuration, the interposing member preferably includes a buffer material and a spacer as its constituent members, and the spacer is preferably positioned only in the middle of the bottom edge of the glass plate.

Glass plates of various sizes may be loaded onto a pallet for packaging glass plates. In this case, the components of the intervening member, which is placed only in the middle of the base of the glass plate, must be prepared in multiple types depending on the size of the base of the glass plate. However, because cushioning material is expensive, preparing multiple types of cushioning material depending on the size of the base of the glass plate increases costs. In contrast, by placing the spacers only in the middle of the base of the glass plate, as in the above configuration, it is possible to suppress cost increases by simply preparing multiple types of spacers, which are cheaper than cushioning material, depending on the size of the base of the glass plate.

In this case, it is preferable that the spacer consists of a laminate of multiple cardboard sheets.

This method further reduces costs, as cardboard laminates are inexpensive. Furthermore, cardboard laminates are easy to cut, making them suitable for glass sheets of various sizes. Furthermore, cardboard laminates do not impair the function of the cushioning material.

In the above configuration, the cushioning material preferably comprises a foam resin material and a rubber material.

This allows the cushioning material to absorb a variety of shocks and vibrations according to the shock and vibration absorption capabilities of the foam resin material and rubber material, respectively.

In the above configuration, the cover member is preferably made of cardboard.

This makes it less likely to tear than slipsheets, etc. Furthermore, these advantages stabilize the shape of the support surface of the cover member, further reducing the risk of the corners of the glass plate getting caught.

The glass plate package of the present invention, which was devised to solve the above problems, is characterized by packaging a glass plate stack in a glass plate packaging pallet appropriately equipped with the above-mentioned configuration.

By doing this, you can enjoy the same effects as the corresponding configuration described above.

The method for manufacturing a glass plate package according to the present invention, which was invented to solve the above problems, is characterized by the step of stacking multiple glass plates in a vertical position with protective sheets interposed between them on a glass plate packaging pallet appropriately equipped with the above-mentioned configuration.

By doing this, you can enjoy the same effects as the corresponding configuration described above.

The present invention provides a glass plate packaging pallet, a glass plate package, and a method for manufacturing a glass plate package that can reduce gaps between glass plates when loading the glass plates.

1 is a perspective view of a glass plate package according to an embodiment of the present invention. FIG. FIG. 2 is a front view of the glass plate package of FIG. 1 . FIG. 2 is a side view of the glass plate package of FIG. 1 . FIG. 2 is a perspective view showing a state in which a glass plate laminate is fixed in the glass plate package of FIG. 1 .

Embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in Figures 1 to 4, the glass plate package 1 according to this embodiment includes a glass plate laminate 2 and a glass plate packaging pallet (hereinafter simply referred to as the pallet) 3. For ease of explanation, the X direction in the figures is the front-to-rear direction, and the Y direction in the figures is the width direction.

The glass plate laminate 2 is formed by stacking multiple glass plates G and protective sheets P alternately in a vertical position (in this embodiment, in an inclined position). In this embodiment, both the glass plates G and the protective sheets P are rectangular, and the protective sheets P are disposed on the front and rear sides of the glass plate laminate 2.

The number of glass plates G in the glass plate laminate 2 is, for example, 200 to 400. The size of the glass plates G is, for example, 730 mm x 920 mm to 3200 x 3600 mm, and the thickness of the glass plates G is, for example, 300 μm to 1500 μm. The glass plates G are, for example, glass substrates for flat panel displays.

The protective sheet P can be, for example, interleaf paper (pure pulp paper) or a foam resin sheet. The size of the protective sheet P is preferably larger than the glass sheets G so that the glass sheets G do not come into direct contact with each other. In other words, the protective sheet P may extend laterally and/or upward in the width direction of the glass sheets G. However, from the perspective of preventing operational errors in robots such as those used in loading and unloading devices for the glass sheets G, it is preferable that the protective sheet P does not extend below the glass sheets G.

The pallet 3 includes a base 4 on which the glass sheet laminate 2 is stored, a back support 5 that flatly supports the back surface of the glass sheet laminate 2, and a bottom support 6 that flatly supports the bottom surface of the glass sheet laminate 2.

The base 4 is constructed from a metal frame made of, for example, stainless steel, carbon steel, or aluminum alloy.

The rear support section 5 includes a rear section 7 that stands upright from the rear side of the base section 4, and a rear cushioning material 8 that is provided on the front surface of the rear section 7. In this embodiment, the rear cushioning material 8 is configured to support the entire rear surface of the glass plate G included in the glass plate laminate 2. Note that the protruding portion of the protective sheet P that protrudes from the glass plate G may or may not be supported by the rear cushioning material 8.

The back portion 7 is made of a metal frame such as stainless steel, carbon steel, or aluminum alloy.

The rear cushioning material 8 can be, for example, a rubber plate, a foamed resin plate, or a laminate of these. The foamed resin plate can be made primarily of, for example, foamed polypropylene, foamed urethane, foamed styrene, or foamed melamine. In this embodiment, the rear cushioning material 8 is a foamed polypropylene plate.

The bottom support portion 6 includes an interposition member 9 between the base portion 4 and the glass plate laminate 2, and a cover member 10 positioned above the interposition member 9.

The cover member 10 is positioned along the entire length of the bottom edge of the glass plate G and is in direct contact with the bottom edge of the glass plate G.

The cover member 10 can be made of, for example, cardboard, plastic corrugated cardboard, glass interleaf paper, or foam resin sheet. In this embodiment, it is made of cardboard. The cardboard that makes up the cover member 10 is made of cardboard such as chipboard, and also includes corrugated cardboard with a multi-layered paperboard structure. Making the cover member 10 out of cardboard in this way has the advantage of being tear-resistant. In this embodiment, the cover member 10 is a single plate material that is continuous in the width direction of the glass plate laminate 2. The thickness of the cover member 10 is preferably, for example, 0.5 mm to 2 mm. The cover member 10 may be reused, but in this embodiment, it is discarded after being used once for transportation.

The interposing member 9 is composed of a laminate of multiple components, at least some of which are arranged only in the middle of the bottom edge of the glass sheet G, excluding both ends of the bottom edge. In other words, a space S where no interposing member 9 is arranged is formed below both widthwise ends of the cover member 10, which supports the corners formed at both ends of the bottom edge of the glass sheet G. In this way, even if the corners of the bottom edge of the glass sheet G press downward on the cover member 10 due to gravity, the cover member 10 uses the space S where no interposing member 9 is arranged to bend slightly downward, preventing the corners of the bottom edge of the glass sheet G from digging into the cover member 10. Therefore, when the glass sheets G are stacked, the corners of the bottom edge of the glass sheets G are less likely to get caught, reducing the formation of gaps between the glass sheets G.

As shown in Figure 2, the width dimension W of the space S where the intervening member 9 is not arranged (or the portion of the cover member 10 that protrudes from the intervening member 9) can be changed as appropriate depending on the dimensions of the glass plate G, but can be set to, for example, 50 mm to 300 mm, and preferably 100 to 200 mm. Furthermore, the height dimension H of the space S where the intervening member 9 is not arranged (or the thickness of the spacer 12, described below) can be changed as appropriate depending on the dimensions of the glass plate G, but can be set to, for example, 2 mm to 20 mm, and preferably 3 to 5 mm.

It is possible to position the cover member 10 only in the middle of the bottom edge of the glass sheet G, but in this case, the corners of the glass sheet G would be free and the resistance to movement of the glass sheet G would be too small. As a result, the glass sheet G would move on the cover member 10 during transport, which could cause damage to the glass sheet G or the cover member 10, or cause dirt due to dust to adhere to the glass sheet G. Therefore, to prevent such problems from occurring, the cover member 10 is positioned along the entire length of the bottom edge of the glass sheet G, as described above.

In this embodiment, the interposition member 9 is composed of a laminate including a bottom cushioning material 11 and a spacer 12 disposed above the bottom cushioning material 11. The bottom cushioning material 11 is disposed along the entire length of the bottom edge of the glass sheet G, and the spacer 12 is disposed only in the middle of the bottom edge of the glass sheet G. The components of the interposition member 9 disposed only in the middle of the bottom edge of the glass sheet G must be prepared in various sizes depending on the dimensions of the bottom edge of the glass sheet G. However, when the bottom cushioning material 11 is disposed only in the middle of the bottom edge of the glass sheet G, the bottom cushioning material 11 is expensive, so preparing multiple types of bottom cushioning material 11 according to the dimensions of the bottom edge of the glass sheet G increases costs. In contrast, when the spacer 12 is disposed only in the middle of the bottom edge of the glass sheet G, the spacer 12 is less expensive than the bottom cushioning material 11, so preparing multiple types of spacer 12 according to the dimensions of the bottom edge of the glass sheet G does not increase costs. Therefore, from a cost perspective, it is preferable to place only the spacers 12, out of the bottom cushioning material 11 and the spacers 12, only in the middle of the bottom side of the glass sheet G. However, if cost is not an issue, both the bottom cushioning material 11 and the spacers 12 may be placed only in the middle of the bottom side of the glass sheet G, or the bottom cushioning material 11 may be placed only in the middle of the bottom side of the glass sheet G, and the spacers 12 may be placed along the entire length of the bottom side of the glass sheet G.

The bottom cushioning material 11 is not particularly limited, but in this embodiment it comprises a foam resin plate (foam resin material) 13 and a rubber plate (rubber material) 14 placed on the upper surface of the foam resin plate 13. In this embodiment, the foam resin plate 13 and the rubber plate 14 are each a single plate material that is continuous in the width direction of the glass plate laminate 2. The bottom cushioning material 11 (particularly the foam resin plate 13) may be discarded after a single use in transportation, but in this embodiment it is used multiple times in transportation and replaced when its cushioning performance (such as thickness recovery) deteriorates.

The foam resin plate 13 can be made primarily of, for example, foamed polypropylene, foamed urethane, foamed styrene, or foamed melamine. In this embodiment, the foam resin plate 13 is a foamed polypropylene plate. The thickness of the foam resin plate 13 is preferably, for example, 10 mm to 30 mm.

The expansion ratio of the foamed resin plate 13 is preferably 10 to 40 times. This allows for both adequate cushioning for the glass sheet G and good thickness recovery. In other words, if the expansion ratio of the foamed resin plate 13 is less than 10 times, the foamed resin plate 13 tends to be too hard, which may result in the desired cushioning not being achieved. On the other hand, if the expansion ratio of the foamed resin plate 13 is more than 40 times, the foamed resin plate 13 tends to be too soft, which may cause the glass sheet G to bounce during loading operations, making it difficult to handle, or may result in poor thickness recovery, making it difficult to reuse. Therefore, to avoid such problems, it is preferable that the expansion ratio of the foamed resin plate 13 be within the above numerical range.

The rubber plate 14 is preferably made of natural rubber, for example, and has a Type A durometer hardness of 50 to 70. The thickness of the rubber plate 14 is preferably 2 mm to 10 mm, for example. By including the foam resin plate 13 and the rubber plate 14 in this way, the base cushioning material 11 can absorb a wide range of shocks and vibrations according to the shock and vibration absorption performance of each. The rubber plate 14 is also expected to have the effect of reducing compressive deformation of the foam resin plate 13. From the perspective of efficiently absorbing shocks and vibrations, it is preferable that the thickness of the rubber plate 14 be smaller than the thickness of the foam resin plate 13. The rubber plate 14 may be omitted.

The spacer 12 can be made of, for example, cardboard, plastic corrugated cardboard, glass interleaving paper, or foam resin sheet. In this embodiment, the spacer 12 is composed of a stack of multiple cardboard sheets. Each cardboard sheet that makes up the spacer 12 is a single sheet of material that is continuous in the width direction of the glass plate laminate 2. The thickness of each cardboard sheet that makes up the spacer 12 can be, for example, 0.3 to 3 mm, and preferably 0.5 to 1.5 mm. The number of cardboard sheets that make up the spacer 12 can be, for example, 1 to 10 sheets (3 sheets in the illustrated example), and preferably 3 to 5 sheets. The cardboard sheets that make up the spacer 12 preferably have the same thickness as the cardboard sheet that makes up the cover member 10. In this way, the original cardboard can be shared between the spacer 12 and the cover member 10 by simply changing the cut size.

As shown in Figure 3, the top surface of the bottom support part 6, i.e., the top surface of the cover member 10, is inclined at a predetermined angle θ1 (e.g., 5° to 25°) with respect to the horizontal, in a direction that transitions upward as it moves away from the back support part 5. Furthermore, the front surface of the back support part 5, i.e., the front surface of the back cushioning material 8, is inclined at a predetermined angle θ2 (e.g., 5° to 25°) with respect to the vertical, in a direction that transitions rearward as it moves away from the bottom support part 6. In this case, the front surface of the back support part 5 is, for example, approximately perpendicular to the top surface of the bottom support part 6.

The glass sheet package 1 configured as described above is shipped (transported) with the glass sheet laminate 2 secured to the pallet 3 by, for example, a predetermined securing means. The securing means is not particularly limited, but may include, as shown in FIG. 4, a belt 15 for restraining the glass sheet laminate 2, a presser member 16 disposed between the belt 15 and the front of the glass sheet laminate 2, and a side stopper 17 disposed between the belt 15 and the side of the glass sheet laminate 2. As shown in FIG. 1, for example, with the glass sheet laminate 2 stored in a vertical position in a predetermined position on the pallet 3, both longitudinal ends of the belt 15 are hooked onto hooks 18 provided on the rear support portion 5, and are fastened in a doubled state to the front of the presser member 16 by a ratchet or the like (not shown). This secures the glass sheet laminate 2 to the pallet 3 with its movement in the front-to-back and left-to-right directions restricted.

At this time, as shown in Figure 4, a frame plate 19 may be placed on the front side of the glass plate laminate 2, and this frame plate 19, the glass plate laminate 2, and the pressing member 16 may be pressed against the rear support part 5 by a belt 15. Furthermore, to prevent dust from adhering to the glass plate laminate 2, the glass plate laminate 2 may be covered with a protective bag or wrapped with a protective film.

The glass plate package 1 configured as described above is manufactured through a manufacturing process that includes stacking glass plates G and protective sheets P alternately in a vertical position on an empty pallet 3. A robot, for example, is used to load the glass plates G and protective sheets P onto the pallet 3.

The present invention is not limited to the configuration of the above-described embodiment, nor is it limited to the effects described above. Various modifications are possible to the present invention without departing from the spirit and scope of the present invention.

In the above embodiment, the intervening member 9 is described as being composed of a laminate of multiple components. However, the intervening member 9 may be composed of a single member. In this embodiment, some or all of the intervening member 9 is disposed only in the middle of the bottom edge of the glass sheet G. More specifically, when all of the intervening member 9 is disposed only in the middle of the bottom edge of the glass sheet G, for example, no intervening member 9 is disposed at both ends of the bottom edge of the glass sheet G. Furthermore, when some of the intervening member 9 is disposed only in the middle of the bottom edge of the glass sheet G, for example, the thickness of the intervening member 9 at both ends of the bottom edge of the glass sheet G is thinner than the thickness of the intervening member 9 at the middle of the bottom edge of the glass sheet G. Alternatively, the intervening member 9 has a gap in the middle of its thickness at both ends of the bottom edge of the glass sheet G. The intervening member 9 may be formed, for example, from a foam resin plate or a rubber plate.

In the above embodiment, the components of the rear support portion 5 and/or bottom support portion 6 may simply be placed separably on top of each other without an adhesive layer between them. In this way, no adhesive is used in the rear support portion 5 and/or bottom support portion 6, which reliably prevents the glass plate G from being contaminated by adhesive. Here, since the bottom support portion 6 is prone to adhesive-related contamination due to vibrations, impacts, etc., it is preferable to adopt a configuration in which no adhesive is used in the bottom support portion 6. Of course, the components of the rear support portion 5 and/or bottom support portion 6 may also be fixed together using adhesive, etc.

In the above embodiment, a rubber plate 14 is placed on the upper surface of a foam resin plate 13 as the bottom cushioning material 11. However, the rubber plate 14 may be placed only on the lower surface of the foam resin plate 13, or on both the upper and lower surfaces of the foam resin plate 13. When rubber plates 14 are placed on both the upper and lower surfaces of the foam resin plate 13, the rubber plate 14 placed on the upper surface of the foam resin plate 13 and the rubber plate 14 placed on the lower surface of the foam resin plate 13 may be of different thicknesses or materials.

In the above embodiment, the foam resin plate 13 is described as being composed of a single foam resin plate 13, but the foam resin plate 13 may also be a laminate of multiple foam resin plates. In this case, the multiple foam resin plates 13 may be stacked directly or with a rubber material interposed between them.

In the above embodiment, the cover member 10 and the interposition member 9 are each constructed from a single plate material that is continuous in the width direction of the glass plate laminate 2. However, if the size of the glass plate G is large, these members may be divided into multiple pieces in the width direction of the glass plate laminate 2.

REFERENCE SIGNS LIST 1 Glass plate package 2 Glass plate stack 3 Glass plate packaging pallet 4 Base 5 Rear support portion 6 Bottom support portion 7 Rear portion 8 Rear cushioning material 9 Interposition member 10 Cover member 11 Bottom cushioning material 12 Spacer 13 Foam resin plate 14 Rubber plate G Glass plate P Protective sheet S Space

Claims (8)

A glass plate packaging pallet including: a base portion on which a glass plate laminate including a glass plate and a protective sheet extending laterally in the width direction of the glass plate is accommodated in a vertical position; a back support portion supporting a back surface of the glass plate laminate; and a bottom support portion supporting a bottom surface of the glass plate laminate,
the bottom support portion includes an interposition member between the base portion and the glass plate laminate, and a cover member disposed above the interposition member;
The cover member is disposed along the entire length of the bottom side of the glass plate,
A pallet for packing glass plates, characterized in that at least a portion of the intervening member is positioned only in the middle of the bottom edge of the glass plate, and a space where the intervening member is not positioned is formed below the cover member at a position corresponding to the corners formed at both ends of the bottom edge of the glass plate. the interposing member is formed of a laminate of a plurality of constituent members,
2. The glass plate packaging pallet according to claim 1, wherein at least a part of the component members is disposed only at the middle of the bottom side of the glass plate. the intervening member includes a buffer material and a spacer as the constituent members,
3. The glass plate packaging pallet according to claim 2, wherein the spacers are disposed only at the middle portions of the bottom sides of the glass plates. A glass sheet packaging pallet as described in claim 3, wherein the spacer is made of a laminate of multiple cardboard sheets. A pallet for packaging glass plates according to claim 3 or 4, wherein the cushioning material comprises a foam resin material and a rubber material. A glass plate packaging pallet according to any one of claims 1 to 5, wherein the cover member is made of cardboard. A glass plate package obtained by packaging the glass plate laminate in the glass plate packaging pallet described in any one of claims 1 to 6. A method for manufacturing a glass plate package, comprising stacking a plurality of glass plates in a vertical position with the protective sheet interposed between them on the glass plate packaging pallet described in any one of claims 1 to 6.