WO2011125071A1

WO2011125071A1 - A pallet for carrying load

Info

Publication number: WO2011125071A1
Application number: PCT/IN2011/000233
Authority: WO
Inventors: Ashok Syal
Original assignee: Ashok Syal
Priority date: 2010-04-08
Filing date: 2011-04-05
Publication date: 2011-10-13

Abstract

This invention relates to a pallet, comprising a number of parallel legs (1) and a deck (2). The deck (2) comprises a deck sheet (200) and on the underside thereof parallel, projecting beam members (202, 203), arranged to join the deck with the legs (1). The beam members have a height (x) which is substantially less than the vertical extent (h) of the legs (1) and a cross- section having a horizontal span which increases from a position close to the deck sheet (200) down towards a lifting surface (204). The leg (1), is substantially hollow, having a polygon shaped cross-section with inclined side walls (100, 121), preferably a triangle, extending up to a point at least essentially in level with the underside of the deck sheet (201). The top portion of each leg (1) has key holes (103) presenting a cross-section matching outer profile of the beam members (202, 203). The lower surface (204) of the beam members (202, 203) forms a lifting surface for lifting devices, such as lifting forks. Further, at least one of the legs (1) is thermally formed and arranged to provide predefined cross-sections presenting equal strength properties along the entire length of the leg (1).

Description

A PALLET FOR CARRYING LOAD

TECHNICAL FIELD

This invention relates in general to containers used in transport and/or handling of goods, and, in particular, to the field of pallets. More specifically, but without restriction to the particular embodiments hereinafter described, this invention relates to a modular pallet, wherein transportation of pallets is easy and economical, and can be assembled without any tools at the location for intended use.

BACKGROUND

Pallets have been in use for long for transporting and/or storing goods. Since the early days wooden pallets are being used due to easy availability of wood for manufacturing the pallets. However, these pallets pose numerous problems as well. The foremost concern is the impact on environment due to cutting of trees for making the pallets. Further, the wooden pallets being vulnerable to moisture, insects and dirt pose a challenge to use them for long in many^■ industries where sanitary working environment is a basic requirement. They need periodic fumigation and cleaning, increasing the operational costs. Also, load carrying capacity of the wooden pallets is fairly low in comparison to their own weight, when compared to the metal or plastic pallets. Another problem associated with wooden pallets is that they often break down and it is expensive to repair them. Also, it is not possible to reuse the material once the pallet is broken. Wooden pallets occupy considerable space of the ware house when not in use as they can not be disassembled conveniently. Metal pallets are durable but their weight is a concern. Also, manufacturing of the metallic pallet is an expensive affair.

Pallets made of non-wooden material, e.g. plastic, cardboard, paper and/or paperboard have previously been proposed with the primary aim of offering a cheaper and less heavy alternative in place of conventional pallets made of wood. However, these pallets have not gained general acceptance in all different fields. The reasons for this may have many different reasons, e.g. too poor a load-bearing capacity, difficulty of handling with lifting forks, too high a price in relation to the technical qualities of the pallet, prohibitive costs for transport from producer to user, difficulties in recovering the material, etc.

From EP 0787098 there is known a pallet, comprising a number of non-wooden parallel legs and a deck, said deck comprising a deck sheet and on the underside thereof parallel, projecting beam members, arranged to join the deck with the legs, said leg , in cross section has the shape of a polygon with inclined side walls, preferably a triangle, extending up to a point at least essentially in level with the underside of the deck sheet, the top portion of each leg having through recesses presenting a cross-section matching said beam members, and the projections form a lifting surface for the lifting forks. This pallet is made from web material, which is folded and thereafter assembled. It has successfully been able to meet many of the needs within different fields, but within some fields it has not met up to the required needs. One of the problems is that fiber based web material, e.g. paper board, may differ in quality from batch to batch, which in turn leads to differences in properties. In some fields such possible differences may not be accepted. Another disadvantage with pallets made from fiber based web material, is that they may have problems in maintaining required properties in humid environments.

With the constant research going on in the field of plastic, it has been possible to develop plastic pallets weighing lighter than wooden pallets yet much stronger. Further, plastic pallets have a longer service life and are resistant to moisture, insects, dirt and various possible contaminations. The fact that the plastic pallets can be recycled increases their charm.

However, owing to the higher cost of production it becomes economically painful to change the entire pallet in case of a minor damage to any part of it. Further, it is difficult to transport the plastic pallets in huge numbers as they have a fixed stiff shape.

SUMMARY OF THE INVENTION

It is an object of the invention to eliminate or at least minimize the above mentioned problems which is achieved by means of a modular pallet assembly in accordance with the appended claims.

A pallet in accordance with the invention which presents a high load to weight capability and also relatively longer operational life resulting in low life cycle costs. Thanks to the use of the innovative design higher ability to withstand loads can be attained. Further, the modular structure allows transportation of greater number of pallets for the same volume and easy assembly at the place of use without using any tools. Moreover, a single module or piece of the entire pallet assembly needs to be replaced in event of damage or breakage resulting in cost savings.

One aspect of the present invention provides a pallet for carrying load, wherein said pallet comprises a number of parallel legs (1) and a deck (2), said deck (2) comprising a deck sheet (200) and on the underside thereof parallel, projecting beam members (202, 203), said beam members (202, 203) having a height (x) which is substantially less than the vertical extent (h) of the legs (1) and a cross-section having a horizontal span which increases from a position close to the deck sheet (200) down towards a lifting surface (204), each of said legs (1) is substantially hollow, has a polygon shaped cross section with inclined side walls (100, 121), extending up to a point at least essentially in level with the underside of the deck sheet (201) and the top portion of each of said legs (1) has keyholes (103) presenting a cross-section matching said beam members (202, 203), wherein said beam members (202, 203) have a lower surface (204) forming a lifting surface for lifting devices, characterized in that said deck (2) is arranged to join with said legs (1) by inserting said beam members (202, 203) in said keyholes (103) to form said pallet.

Further advantages and aspects of the invention will be presented in the following part of the description.

BRIEF DESCRIPTION OF THE DRAWINGS

The following invention will be described more in detail with reference to the enclosed figures, wherein:

Fig. 1 shows a perspective view of an assembled pallet, in accordance with an embodiment of the present invention;

Fig. 2 shows a side view of the assembled pallet, in accordance with an embodiment of the present invention:

Fig. 3a shows a side view of a support, in accordance with the invention;

Fig. 3b shows an enlarged view of a section shown circled in Fig. 3a;

Fig. 4 shows another side view of the support, in accordance with an embodiment of the present invention;

Fig. 5 shows a perspective bottom view of a deck element, in accordance with the invention ; Fig 6 shows a side view of the deck Element, in accordance with the invention. DETAILED DESCRIPTION

The present invention provides a pallet for carrying load which is manufactured using an engineering material. The pallet is easy to assemble and disassemble, hence it is easy to store or transport. In case damage takes place to a particular part of the pallet it is not mandatory to replace the whole pallet, only the damaged portion can be replaced.

One embodiment of the present invention provides a pallet for carrying load, wherein said pallet comprises a number of parallel legs (1) and a deck (2), said deck (2) comprising a deck sheet (200) and on the underside thereof parallel, projecting beam members (202, 203), said beam members (202, 203) having a height (x) which is substantially less than the vertical extent (h) of the legs (1) and a cross-section having a horizontal span which increases from a position close to the deck sheet (200) down towards a lifting surface (204), each of said legs

(1) is substantially hollow, has a polygon shaped cross section with inclined side walls (100, 121), extending up to a point at least essentially in level with the underside of the deck sheet (201) and the top portion of each of said legs (1) has keyholes (1 3) presenting a cross-section matching said beam members (202, 203), wherein said beam members (202, 203) have a lower surface (204) forming a lifting surface for lifting devices, characterized in that said deck

(2) is arranged to join with said legs (1) by inserting said beam members (202, 203) in . said keyholes (103) to form said pallet.

One embodiment of the present invention provides a pallet, wherein said polygon shaped cross-section comprises an internal support structure (109) integrated with the side walls (100, 101 , 121).

One embodiment of the present invention provides a pallet, wherein said internal support structure (109) is arranged to form a mesh like structure.

One embodiment of the present invention provides a pallet, wherein said internal support structure (109) has top surface (112) arranged to be in level with or below a bottom support surface (104) of key holes (103), wherein said top surface (1 12) provides extra support to said lower surface (204) of the beam members (202, 203).

One embodiment of the present invention provides a pallet, wherein said deck (2) is formed by a number of parallel deck elements (2) presenting the same cross-sectional form.

One embodiment of the present invention provides a pallet, wherein said legs (1) have a triangular cross-section.

One embodiment of the present invention provides a pallet, wherein at least one of the said deck elements (2) is thermally formed presenting substantially hollow beam members (202, 203). One embodiment of the present invention provides a pallet, wherein cross-section of said beam members (202, 203) comprises an internal support structure (207, 208)) that is integrated with the side walls (205, 206) of said beam members (202, 203).

One embodiment of the present invention provides a pallet, wherein said deck sheet (200) comprises a grooved upper surface (21 1).

One embodiment of the present invention provides a pallet, wherein said deck elements (2) comprise overlapped portions (213, 216) on either side, wherein said overlapped portions (213, 216) facilitate overlapping among said deck elements (2) to form a continuous deck sheet (2), and wherein thickness of said overlapped portions (213, 216) is less than the thickness of the thickest portion of said deck sheet (2).

One embodiment of the present invention provides a pallet, wherein said side walls (205, 206) comprise keymembers (209, 210) and said keyholes (103) comprise recesses (107, 108) presenting matching cross-section to said keymemebers (209, 210), wherein keymembers (209, 210) slide in said recesses (107, 108) presenting a frictional fit in a dovetailing manner.

One embodiment of the present invention provides a pallet, wherein said leg comprises one or more than one blocks fitted to form a single leg.

One embodiment of the present invention provides a pallet, wherein said deck sheet comprises one or more than one deck elements arranged to form a single deck sheet.

One embodiment of the present invention provides a pallet, wherein said pallet is customizable according to the requisite size.

One embodiment of the present invention provides a pallet, wherein each said deck sheet (200) has provision of one or more holes in order to lock the deck sheet with the help of a locking means to prevent the sliding of the deck structure.

One embodiment of the present invention provides a pallet, wherein each said leg (2) has provision of one or more holes in order to fix the leg with the help of a fixing means to stabilize the deck structure.

Figures 1 and 2 show different views of an assembled modular pallet, in accordance with an embodiment of the invention. In Fig. 1 a perspective view of the assembled pallet is shown from the top, disclosing distinct parts of the assembled body pallet, namely three legs 1 and a deck. The deck is built using five deck elements (2). Each deck element (2) comprises two identical beam members (202, 203). The beam members (202, 203) are inserted in the keyholes (103) in each leg 1, as shown in fig. 2, interconnecting the deck element (2) with the legs 1.

In an embodiment, deck elements are configured in such a manner that it maximizes the load surface making a uniform layer having no gaps on the surface and hence increasing load carrying capacity of the pallet. The deck is manufactured using an antiskid element or atleast the upper surface is manufactured using antiskid element. To achieve this object, the upper surface of the pallet is atleast partially provided with friction-enhancing material.

Fig.3a shows a side view of the leg 1 in accordance with the invention. The height of the support is maintained such that it allows easy accessibility to fork lifters, as will be explained more in detail below. As per an embodiment, there are ten keyholes (103) in the leg 1. Fig. 3b shows an enlarged view of one of the keyholes (103). Each keyhole (103) has a generally triangular shape with the converging sides (105, 106) having a radius of curvature in a manner to present convexly effacing sides (105, 106). Further, each keyhole (103) is symmetric in relation to an imaginary vertical center line passing through a bottom support surface (104) and an opening (120) at the top surface (102) of the leg 1. Furthermore, each of the converging sides (105, 106) is connected to a form of circular holes (107) by means of a narrow slit (108), as shown in fig. 3b. Also, the height of each keyhole (103) is about 20 - 40 percent of the height (h) of the leg 1. The leg 1 can be manufactured as a single piece. Alternatively, it is possible to manufacture a single leg in more than one piece. Two or more pieces of a leg can be manufactured in a tapered design in such a way that they can be fitted with each other to make a single leg. Alternatively, male and female recesses can be made in leg parts in such a way that when connected they can be fixed in a snap fit position by rotating. Alternatively, different pieces of a leg can be joined by passing a single solid rod or a hollow rod through all the pieces of the leg and the terminals of the rod can be locked with snap fitted cap. Manufacturing a leg in pieces is useful as it helps in manufacturing a small pallet as per requirement using one or two deck elements. Alternatively it is also possible to make a large modular pallet by joining more leg pieces. One can cut holes in the legs at their ends to lock them against the deck sheet in an assembled position. It will prevent the legs from slipping when a pallet is lifted in an assembled position. In another embodiment a solid rod or a hollow rod can be inserted in the holes which can be locked on the ends and hence prevent displacement of the legs from their position. Fig. 4 shows another side view of the leg 1 along the short end. As shown, the leg 1 has a triangular cross section, being symmetric in relation to the imaginary vertical center line. Further, the triangular cross section is isosceles, i.e. lengths of the sides (100, 121) are same. The bottom side (101) of the triangular cross section has smaller length than the sides (101 , 121). However, thickness ( t_j ) of all three sides (100, 101, 121) is same throughout, except near the vertices. In one embodiment, length of the bottom side of the triangular cross section is greater than the other two sides. Thickness of the bottom side (101) can be reduced as per requirements.

Within the hollow space created by the sides (100, 101, 120) of the support there is arranged an integrally formed support structure (109).The support structure (109) is formed by a number of parallel extending vertical support foils (1 10) and a number of parallel horizontal support foils (1 1 1). The support foils (110, 111) are integrated and form a mesh like support structure (109) by crossing and interconnecting vertical and horizontal support foils, as shown in fig. 4. The horizontal support foils (111) extend from one side (121) to the other (100) of the outer walls of the triangular cross section. The vertical support foils (1 10) extend from the bottom side (101) to the top most horizontal support foil (111), as shown in fig. 4. As a result, the support structure (109) remains in the lower part of the leg 1 and leaves an open space adjacent to the top (102) of the leg 1. This open space is defined by the upper surface (112) of the top most horizontal support foil (1 1 1).

Each of the support foils (1 10, 1 1 1) have the same thickness (t₂ ), which is less than the thickness (/, ) of the three sides (100, 101, 1 12) of the leg 1, as per an embodiment. In another embodiment, t, is at least two times larger thant₂ . In yet another embodiment, the following relationship: t₂≤ t, < 4 x t₂ can be used. Based on this, the design of the leg 1 can be optimized from a view point of strength and weight. The design of the present invention is suited for production using different raw materials, such as plastic, metal, etc. Similarly, corresponding to the raw material being used, various manufacturing processes, such as extrusion, injection molding, etc., can be used. Further, as shown in fig. 4, the top (102) surface of the leg 1 is a flat horizontal surface, perpendicular to the plane of the triangular cross section, which will form the support surface in contact with each deck member (2), as shown in fig. 1.

Further, in an embodiment, the support structure (109) can have the top surface (1 12) of the horizontal support foils (1 1 1) arranged to be in level with the bottom support surface (104) of each key hole (103). Thus, the top surface (112) can provide extra support to the lower surface (204) of the beam members (202, 203).

Fig. 5 shows a perspective bottom view of a deck element (2), in accordance with the invention. As already mentioned, each pallet will be formed by the use of a number of deck elements (2) interconnected by means of its beam members (202, 203) with a number of legs 1. As evident, pallets of different sizes and load-carrying capacity can easily be produced by means of varying the number of deck elements and/or their length, in combination with varying number of legs 1 and/or their length. The deck elements (2) are produced by means of extrusion, as per an embodiment. As per another embodiment the deck elements (2) are produced by means of injection molding. As is evident for the skilled person production of deck elements (2) can be achieved using various other manufacturing processes known in the art. Fig 6 shows a side view of the deck Element (2), in accordance with the invention. As is evident each beam member (202, 203) has similar cross sectional shape. Further, each beam member (202, 203) has a cross sectional outer configuration that is adapted to the keyholes (103) and allows the beam members (202, 203) to slide in and provide frictional fit with the keyholes (102). ^' Hence the beam members (202, 203) comprise a triangularly shaped body having flat bottom parts (204) and concave side walls (205, 206). Perpendicularly protruding in relation to each side wall (205, 206), there are keymembers (209, 210), as per an embodiment. The keymembers (209, 210) are adapted to fit into the corresponding recesses (107, 108) in the legs 1. The keymembers comprise an inner part (210), in the form of a horizontally extending wall part with a U shaped outer member (209) at the end. The keymembers (209, 210) have a dimension allowing them to slide in and frictional fit with the recesses (107, 108). A skilled person can notice that the use of the key members (209, 210) is provided in an embodiment for locking the deck members (2) with the leg 1 and the same can be achieved with other means, fulfilling the basic principles of the invention and without the use of these key members (209, 210) and the corresponding keyholes (107, 108). The deck sheet (200) attached to each deck element (2) includes an upper surface (211) with grooves formed in it. More specifically, the upper surface (211) of the deck is manufactured of an antiskid surface. The surface is manufactured using a friction enhancing material.

This unique structure provides a lesser slippery deck surface of the pallet ensuring added safety of the object placed over the deck surface. Along each side end of each deck element (2) overlapped portions (216, 213) have been provided. These overlapped portions (213, 216) facilitate overlapping with other deck elements (2) when the deck elements are fit together to form a continuous deck sheet.

To facilitate an overlap at the edges, the thickness (t₃ ) of these portions (213, 216) is less compared to the thickness (t₄ ) of the thickest portion of the deck sheet (200). As per an embodiment, the thickness ( t₃ ) of the edge portions is half of the thickness ( t₄ ) of the thickest portion of the deck sheet (200). Accordingly, at one side there will be formed a transition edge (214) between the underside (201) and a downwardly directed surface of a first overlapped portion (213). A similar transition edge (217) will form on the second overlapped portion (216). As is evident the outer edge (212) of the first overlapped portion (213) will be positioned adjacent the transition edge (217) of the second overlapped portion (216) when fit together.

The material used for manufacturing of a pallet is not necessarily required to be of a particular type. Any material having a desired strength to support the weight of the load and characteristic to maintain the shape of the pallet is acceptable. For example, general corrugated fiberboard, honeycomb structure materials made from paper, cardboard, Kraft paper, plastic or any suitable engineering material may be used. The material used for manufacturing of the pallet may be laminated or fiber reinforced to provide additional strength. The deck elements and the leg members may also be manufactured using different types of materials.

Another advantage offered by these pallets is that they can be manufactured according to more specific and adapted shapes and the material usage can be reduced. Lower weight pallets ensure convenience of handling and shipping. Moreover, a single module or piece of the entire pallet assembly needs to be replaced in event of damage or breakage resulting in cost savings. Also, there is no requirement of using tools to assemble the deck and legs to manufacture pallet of a desired size at the location intended for use. The invention is not limited by what has been described above but may be varied in the scope of the independent claims in various manners as is evident to a skilled person. For instance, in an embodiment there may be no need for the key members (209, 210), while in another embodiment a greater number of key members (209, 210) can be used, depending upon specific requirements. Further it is evident that the cross sectional design of the beam members may be varied but still providing the basic functionality in accordance with the desired presented above. However, an important advantage by the use of triangularly shaped keyholes (103) is that the legs 1 can also be used in connection with a deck that is formed from a web shaped material, whereby the corresponding beam portions are formed by pressing a corresponding part of the web into the keyhole. Furthermore it is evident that the exact design of the deck elements (2) may be varied, for e.g. each deck element (2) merely comprising one beam portion or including three or four beam portions.

Claims

I/We Claim:

1. A pallet for carrying load, wherein said pallet comprises a number of parallel legs (1) and a deck (2),

- said deck (2) comprising a deck sheet (200) and on the underside thereof parallel, projecting beam members (202, 203),

- said beam members (202, 203) having a height (x) which is substantially less than the vertical extent (h) of the legs (1) and a cross-section having a horizontal span which increases from a position close to the deck sheet (200) down towards a lifting surface (204),

- each of said legs (1) is substantially hollow, has a polygon shaped cross section with inclined side walls (100, 121), extending up to a point at least essentially in level with the underside of the deck sheet (201) and the top portion of each of said legs (1) has keyholes (103) presenting a cross-section matching said beam members (202, 203),

- wherein said beam members (202, 203) have a lower surface (204) forming a lifting surface for lifting devices,

characterized in that said deck (2) is arranged to join with said legs (1) by inserting said beam members (202, 203) in said keyholes (103) to form said pallet.

2. The pallet as claimed in claim 1, wherein said polygon shaped cross-section comprises an internal support structure (109) integrated with the side walls (100, 101 , 121).

3. The pallet as claimed in claim 2, wherein said internal support structure (109) is arranged to form a mesh like structure.

4. The pallet as claimed in claim 2, wherein said internal support structure (109) has top surface (112) arranged to be in level with or below a bottom support surface (104) of key holes (103), wherein said top surface (1 12) provides extra support to said lower surface (204) of the beam members (202, 203).

5. The pallet as claimed in claim 1, wherein said deck (2) is formed by a number of parallel deck elements (2) presenting the same cross-sectional form.

6. The pallet as claimed in claim 1, wherein said legs (1) have a triangular cross-section.

7. The pallet as claimed in claim 5, wherein at least one of the said deck elements (2) is thermally formed presenting substantially hollow beam members (202, 203).

8. The pallet as claimed in claim 7, wherein cross-section of said beam members (202, 203) comprises an internal support structure (207, 208)) that is integrated with the side walls (205, 206) of said beam members (202, 203).

9. The pallet as claimed in claim 1 , wherein said deck sheet (200) comprises a grooved upper surface (21 1).

10. The pallet as claimed in claim 5, wherein said deck elements (2) comprise overlapped portions (213, 216) on either side, wherein said overlapped portions (213, 216) facilitate overlapping among said deck elements (2) to form a continuous deck sheet (2), and wherein thickness of said overlapped portions (213, 216) is less than the thickness of the thickest portion of said deck sheet (2).

1 1. The pallet as claimed in claim 8, wherein said side walls (205, 206) comprise keymembers (209, 210) and said keyholes (103) comprise recesses (107, 108) presenting matching cross-section to said keymemebers (209, 210), wherein keymembers (209, 210) slide in said recesses (107, 108) presenting a factional fit in a dovetailing manner.

12. The pallet as claimed in claim 1, wherein said leg comprises one or more than one blocks fitted to form a single leg.

13. The pallet as claimed in claim 1 , wherein said deck sheet comprises one or more than one deck elements arranged to form a single deck sheet.

14. The pallet as claimed in claim 1, wherein said pallet is customizable according to the requisite size.

15. The pallet as claimed in claim 1 , wherein each said deck sheet (200) has provision of one or more holes in order to lock the deck sheet with the help of a locking means to prevent the sliding of the deck structure.