Nested tray with improved shelf and conveyor performance

Abstract

A nestable tray with improved shelf and conveyor performance is provided. The nestable tray (100, 200, 300, 400) has a platform (102) for supporting a load and a set of a plurality of hollow struts (106) having an upper opening and an inwardly tapered inner surface (108) for receiving portions of a respective strut of another tray when a plurality of similar trays are stacked. Some of the plurality of hollow struts have a peripheral support arrangement including a lower strut extension (110) projecting horizontally from an inwardly tapered portion of the strut toward an edge (112) of the tray, and an upper strut opening (114) projecting from an inwardly tapered portion of the strut toward the edge (112) of the tray. The upper strut opening (114) is for receiving the lower strut extension of another tray when a plurality of similar trays are stacked.

Description

[0001] Technical field and background technology

[0002] The present invention relates to various pallets and, more particularly, to a nestable pallet having improved racking, stacking and conveyor capabilities.

[0003] Conventional pallets are usually made of wood and have a load-bearing platform 1000 and a plurality of slide members 1002 contacting the ground, such as Figure 1 The plurality of slide members extend to the plurality of ends of the tray.

[0004] It is known that a plurality of trays 1004 ( Figure 2A ) has many advantages, such as being strong and reusable. In order to facilitate compact transportation backhaul, multiple pallets sometimes use multiple hollow tapered support structures 1006 so that they can be closely nested with multiple other similar pallets. In order to facilitate nesting and position the multiple supports within the peripheral wall of the platform, it is necessary to taper inward, which causes the lower part of the support to deviate significantly from the edge of the pallet platform. Figure 2A Indicated by d.

[0005] Nestable pallets are becoming more and more popular because they take up much less volume when empty and stacked together. Typically, a stack of nested pallets can hold about three times as many pallets in the same volume as a conventional (with a base) pallet with the same outer dimensions. However, nestable pallets have a number of limitations or disadvantages due to their geometry. In order to achieve nesting, the multiple nestable pallet struts require a certain draft angle so that they can be nested together and can be easily separated when nested. This means that the pallet struts at the bottom (where they touch the floor or a supporting surface) do not reach the outer dimensions of the pallet top platform and are tilted inwards. Typically, for a pallet of 120 cm in length, this means that the bottom struts are at least 4 cm "d" away from the pallet perimeter at each end, and usually more.

[0006] This position of the plurality of legs being recessed from the edge of the pallet limits the functionality of the pallet in various ways. Firstly, it results in a lower safety margin when stored between two beams, e.g. Figure 2B As shown. The outer distance between the multiple pillars of a traditional (e.g. wooden) pallet is the full length of the pallet, which is 120 cm for a 120 cm*100 cm pallet. The outer dimensions of the multiple pillars at the bottom of a nestable pallet are usually 120 cm-8 cm=112 cm or less. The outer dimensions between the multiple beams of a racking system are fixed, usually about 110 cm. This means that when a traditional pallet is placed on these racks, it has a larger safety margin than a nestable pallet. Figure 2B Shown are the "correct" (solid lines) and "incorrect" (dashed lines) positions of a nestable pallet on multiple beams of a rack.

[0007] Figure 2C Another limitation of conventional nested pallets is shown, involving the inability to "double stack" a nested pallet on open crates. As shown in the figure, the outer legs of the pallet do not reach the walls of the lower crates, causing the upper pallet to be unstable and / or press on the contents of the crates.

[0008] Another problem is related to use on a conveyor. Nestable pallets may be at greater risk of rotation when transported on a conveyor (roller or chain) because the alignment of the pallet on the conveyor is achieved by guides on both sides of the conveyor, at the height of the plurality of legs. For nestable pallets, the width of the plurality of legs anywhere below the bottom or top deck is less than the full width of the pallet on its top deck. This causes the pallet to twist, e.g. Figure 2D This may cause the tray to become caught by objects, etc. Summary of the invention

[0009] The present invention is a nestable pallet with improved rack and conveyor performance.

[0010] According to the teachings of an embodiment of the present invention, a nestable pallet for supporting a load above a floor is provided, comprising: (a) a platform having an upper surface for supporting the load, the platform having an outer periphery; and (b) a group of multiple hollow pillars rigidly connected to the platform and extending downwardly from the platform to support the platform above the floor, each of the multiple hollow pillars having an upper opening and an inwardly tapering inner surface for receiving a portion of a corresponding pillar of another pallet when multiple similar pallets are stacked, wherein the multiple hollow pillars adjacent to the outer periphery each include a peripheral support configuration, the peripheral support configuration including: (i) a lower pillar extension portion protruding horizontally from an inwardly tapering portion of the pillar toward an edge of the pallet, corresponding to a downwardly protruding portion of the outer periphery, and (ii) an upper pillar opening for receiving the lower pillar extension portion of another pallet when multiple similar pallets are stacked.

[0011] According to further features of an embodiment of the present invention, the lower support pillar extension forms a closed-shaped portion of the lower portion of the support pillar.

[0012] According to further features of an embodiment of the present invention, the inwardly tapered portion of the strut has a taper angle of at least 3 degrees, and wherein the lower strut extension has a draft angle of no more than 2 degrees.

[0013] According to further features of an embodiment of the present invention, the perimeter of the platform is continuous around the platform, and wherein the lower leg extensions are sized to fit within the perimeter when a plurality of similar trays are stacked.

[0014] According to a further feature of an embodiment of the present invention, the inwardly tapered inner surface of each of the multiple hollow struts defines a generally rectangular horizontal cross-sectional shape, and wherein at least one edge of the rectangular horizontal cross-sectional shape is interrupted by the upper strut opening and the lower strut extension, and the lower strut extension extends beyond the rectangular horizontal cross-sectional shape.

[0015] According to further features of an embodiment of the present invention, at least one of the plurality of hollow pillars adjacent to a corner of the platform is formed with two of the peripheral support configurations extending toward two adjacent edges of the tray.

[0016] According to further features of an embodiment of the present invention, the plurality of hollow pillars are integrally formed with the platform.

[0017] According to further features of an embodiment of the present invention, the plurality of hollow struts are mechanically attached to the platform. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention is described by way of example only and with reference to the accompanying drawings, in which:

[0019] Figure 1 , as described above, is a schematic partial side view of a conventional non-nesting pallet;

[0020] Figure 2A , as described above, is a schematic partial side view of a conventional nestable pallet;

[0021] Figures 2B to 2D , as mentioned above, are Figure 2A Schematic diagram of the functional limitations of the pallet during racking, stacking and transportation;

[0022] Figure 3A is an isometric view of a tray constructed and operative in accordance with the teachings of one embodiment of the present invention;

[0023] Figure 3B and 3C They are Figure 3A Magnified views of the regions marked I and II;

[0024] Figure 3D yes Figure 3A A plan view of the tray;

[0025] Figure 3E yes Figure 3A A side view of the tray;

[0026] Figure 3F yes Figure 3A an end view of the tray;

[0027] Figure 3G is along Figure 3D A cross-sectional view taken along line III-III in FIG.

[0028] Figure 3H yes Figure 3A A bottom view of the tray;

[0029] Figure 4A yes Figure 3G An enlarged view of one of the pillars of the tray shown in the area marked IV;

[0030] Figure 4B yes Figure 4A An isometric cross-sectional view of a support column of the pallet taken along plane VV;

[0031] Figure 5A It shows two nested Figure 3A an isometric view of the pallet;

[0032] Figure 5B It is cut along the plane marked VI Figure 5A A cross-sectional view of the nested tray;

[0033] Fig. 6A and Figure 6B The tray is cut along a vertical plane parallel to the length and width of the tray. Figure 3A An isometric cross-sectional view of a corner support of the pallet;

[0034] Fig. 7A is an isometric view of a tray constructed and operative in accordance with the teachings of another embodiment of the present invention;

[0035] Figure 7B and 7C They are Fig. 7A Magnified view of regions labeled VII and VIII;

[0036] Fig. 8A It shows two nested Fig. 7A a lower isometric view of the tray;

[0037] Figure 8B yes Fig. 8A The enlarged view of the area marked as IX;

[0038] Fig. 9Ais a schematic vertical cross-sectional partial view of another variant implementation of a pallet according to an embodiment of the present invention taken through the plurality of posts of two nested pallets, wherein a lower post extension diverges outwardly from a generally inwardly tapering profile of the plurality of posts;

[0039] Fig. 9B is a partial isometric view of a pallet support showing Fig. 9A A first alternative embodiment of the bifurcated lower strut extension;

[0040] Fig. 9C is a schematic vertical cross-sectional partial view of a pallet support, showing Fig. 9A A second alternative embodiment of the bifurcated lower strut extension;

[0041] Fig.10 is a schematic partial isometric view of a pallet support column according to another alternative embodiment of the present invention;

[0042] Fig.11A and 11B is a schematic vertical cross-sectional partial view of a tray support according to another embodiment of the present invention, showing a pivotally retractable lower support extension in an extended state and a retracted state, respectively; and

[0043] Fig. 12A and 12B is a schematic vertical cross-sectional partial view of a tray support according to another embodiment of the present invention, showing a slidably retractable lower support extension in an extended state and a retracted state, respectively. DETAILED DESCRIPTION

[0044] The present invention is a nestable pallet with improved rack and conveyor performance.

[0045] The principles and operation of various trays according to the present invention may be better understood with reference to the several drawings and accompanying description.

[0046] Referring now to the accompanying drawings, FIGS. 3-10 illustrate various embodiments of a nestable pallet, generally designated 100, 200, 300, 400, constructed and operative in accordance with the teachings of various embodiments of the present invention for supporting a load above a floor. Generally, the nestable pallet has a platform 102 and an outer periphery 104 that provides an upper surface for supporting the load. A plurality of hollow struts 106 are rigidly coupled to the platform 102 and extend downwardly therefrom to support the platform above the floor. Each hollow strut 106 has an upper opening and an inwardly tapered inner surface 108 for receiving a portion of a corresponding strut of another pallet when a plurality of similar pallets are stacked.

[0047] The plurality of hollow struts, which may be some or all of the plurality of struts adjacent the periphery 104, each have a periphery support configuration including a lower strut extension 110 and an upper strut opening 114, the lower strut extension 110 projecting horizontally from an inwardly tapered portion of the strut toward an edge 112 of the tray defined by a downwardly projecting portion of the periphery 104 (see Figure 4A ), the upper support opening 114 is used to receive the lower support extension of another pallet when multiple similar pallets are stacked.

[0048] The advantages of this strut arrangement are readily understood. On the one hand, the struts maintain the overall preferred geometry of the struts for nestable pallets, which requires a significant inward taper angle, preferably at least 3 degrees, and typically about 4 degrees, to provide compact nestability and strength. The taper angle is determined by the nesting geometry. For a pallet with a platform approximately 145 mm above the floor, a nesting depth of approximately 85 mm, a vertical spacing of approximately 60 mm between consecutive pallets, and a wall thickness of approximately 4 mm, the clearance of the nested struts requires an inverse tangent (4 / 60) angle, which is close to 4 degrees, and is therefore a good choice to ensure adequate clearance and avoid wedging of the nested pallets together. At the same time, by providing a lower strut extension 110 that protrudes toward the edge 112 of the pallet, the ends of the struts are brought closer to the ends of the pallet, thereby improving the above reference. Figures 2B to 2D During nesting of multiple empty pallets, the lower leg extensions 110 are received by the corresponding upper leg openings 114 of a lower pallet, and when multiple similar pallets are stacked, the lower leg extensions are preferably stacked on top of the lower leg extensions of the lower pallet, such as Figure 5A and 5B Thus, the wall of the lower support extension may be vertical, or nearly vertical, depending on the draft angle required during manufacturing to ensure reliable demolding from a mold. A draft angle is preferably less than 2 degrees, and generally about 1 degree is sufficient. Representative values ​​of these angles are shown in FIG. Figure 4A shown.

[0049] As a matter of terminology, a taper, angle, or slope is referred to herein as "inward" or "converging," which refers to a slope toward the center of the post, such that as you move from the platform toward the bottom of the post, the surface gets closer to the center. Similarly, "outward" refers to a slope that gradually moves away from the center of the post from the platform toward the bottom of the post. Thus, the major interior surfaces 108 of all pallet posts described herein (except for the lower post extension area) are referred to as tapering inwardly.

[0050] The plurality of struts 106 are depicted as being rigidly coupled to the platform 102. In a first set of preferred embodiments, the plurality of struts and platform are integrally formed in a single injection molding manufacturing process. This option provides the greatest strength-to-weight ratio and reduced manufacturing costs, but limits the options for repairing a damaged pallet. In certain alternative preferred embodiments (not shown), the plurality of strut structures may be manufactured separately and then attached using any suitable form of attachment. Advantageously, the plurality of struts are attached using a reversible form of attachment, such as an arrangement of a plurality of threaded fasteners (a plurality of screws or a plurality of bolts), thereby facilitating replacement and alteration of any damaged struts.

[0051] exist Figures 3A to 9B In a preferred but non-limiting embodiment, the perimeter 104 of the platform is continuous (uninterrupted) around the platform 102, thereby optimally increasing the rigidity and strength of the pallet. Therefore, the dimensions of the lower leg extensions 110 are designed so that they fit within the perimeter when multiple similar pallets are stacked. Therefore, the span between the relatively protruding lower leg extensions 110 at opposite ends of the pallet is typically at least about 6 mm (3 mm at each edge) less than the outer dimension of the platform to accommodate the wall thickness of the perimeter of the platform outside the upper leg openings (which may optionally be locally thinned compared to the wall thickness used around the rest of the perimeter of the platform). The inset of the multiple lower leg extensions 110 relative to the edge 112 of the tray is preferably between 6 mm and 20 mm, and most preferably in the range of 7 to 10 mm. By placing the ends of the multiple legs within 2 cm of the edge of the tray, and in some cases within 1 cm of the edge, the above referenced Figures 2B to 2D Most of the limitations of conventional nestable pallets are eliminated, thereby enabling the plurality of pallets to be used with similar functionality as non-nestable pallets.

[0052] In the embodiment of the tray 100, the lower leg extension is formed as an outward undulation of the leg wall, thereby forming a closed shaped portion of the lower portion of the leg. Figure 4BThe support strut 106 is best seen in a view cut in a horizontal plane as shown. As seen there, the inwardly tapering inner surface 108 of the hollow strut 106 defines a generally rectangular horizontal cross-sectional shape, and at least one edge of the rectangular horizontal cross-sectional shape is interrupted by the upper strut opening and the lower strut extension, wherein the lower strut extension extends beyond the rectangular horizontal cross-sectional shape. The "generally rectangular" shape is generally a rounded rectangle, and the radii of the multiple rounded corners may vary along the height of the strut because the horizontal dimension and geometry are changed by the taper angle. Most of the strength of the molded polymer struts is provided by these corner portions, so the lower strut extension and upper strut opening are preferably implemented as modifications of multiple flat areas of the multiple strut walls while leaving the multiple corner areas intact along the entire height of the strut. A set of strengthening ribs 116 are generally provided on the lower portion of the hollow strut, which is common in the art and provides additional rigidity and provides a surface against which the feet of a tray can be rested when nested, such as Figure 5B As shown, over-insertion and wedging of the multiple trays are prevented. Figure 4B A slot 118 can also be seen in the figure, and the slot 118 is optionally provided to insert a radio frequency identification (RFID) to support various pallet tracking functions.

[0053] The choice of positioning of the peripheral support arrangement depends on the intended application. For example, for racking, it may be sufficient to provide the peripheral support arrangement on the plurality of pillars at both ends of the short sides of the pallet. However, in order to obtain maximum application flexibility, it is generally preferred to provide peripheral support arrangements along all four sides of the pallet. To this end, the plurality of hollow pillars adjacent to the plurality of corners of the platform are preferably provided with two peripheral support arrangements extending to two adjacent edges of the pallet, e.g. Figure 3B and 3C In certain applications, such as in the pallet conveyor system, a central pallet stop is used to align the pallet before changing direction, and preferably a peripheral support arrangement is also provided on an intermediate support column adjacent to the long side of the pallet to ensure that the pallet stop is always aligned with the pallet.

[0054] Now turn to reference Figures 7A to 8B, a nestable pallet constructed and operative in accordance with another embodiment of the present invention is shown, the pallet 200 being substantially similar to the above-described pallet 100, with a plurality of equivalent features similarly labeled. The pallet 200 differs from the pallet 100 primarily in that the plurality of posts 216 of the pallet 200 replace the plurality of generally rectangular posts 116 of the pallet 100 with openings of reduced size, thereby providing greater continuity (a plurality of smaller openings) on the upper surface of the platform 102. As a non-limiting example, the cross-sectional shape of the plurality of posts shown here is similar to the cross-sectional shape disclosed in U.S. Patent No. 11,820,551, wherein each post has a horizontal cross-sectional shape consisting of a plurality of relatively long and thin shapes intersecting to form a plurality of posts in a generally T- or H-shaped shape. These shapes are modified by the addition of the above-described peripheral support configurations (including a plurality of lower post extensions 110 and a plurality of upper post openings 114). In all other respects, the pallet 200 is structurally and functionally similar to the pallet 100, and will be clearly understood by analogy with the plurality of structures and functions described and illustrated above.

[0055] Now turn to reference Figures 9A to 9C Although the above-described embodiments show multiple lower leg extensions 110 as being vertical or having a slightly inwardly angled draft angle, an alternative embodiment of a tray 300 may provide a lower leg extension 110 that is angled outwardly toward the base of the leg to ensure that the closest point of contact with an underlying surface is the point at which the leg is closest to the end of the tray. Fig. 9A This is schematically illustrated in Figure 1, where the lower leg extension is shown as a thickened portion of the leg wall. For example, this thickened portion may be provided by attaching an extension component (e.g. by adhesive, heat welding or by any other suitable form of mechanical attachment). Alternatively, the lower leg extension may be formed as part of the main injection molding process of the pallet manufacturing using a suitable mold. Fig. 9B One possible implementation of injection molding is shown, requiring a lateral movement of the core to form an external rib structure to support the extension. Fig. 9C An alternative approach is shown in which a mould is designed to form an outwardly sloping wall portion of normal wall thickness to provide the lower strut extension 110. This can be achieved by using a lower mould portion that extends upwardly into the interior volume of the strut in the area of ​​the lower strut extension and a complementary upper mould portion that extends downwardly through the upper strut opening 114 to define the outer surface of the lower strut extension. Designing a mould to produce Fig. 9B and 9C Various design considerations for the embodiments of the present invention will be apparent to those of ordinary skill in the art.

[0056] Now turn to reference Fig.10 , while the above-described embodiments all maintain a continuous perimeter 104 around the platform 102, certain alternative embodiments of a pallet 400 utilize an upper leg opening 114 that extends to the periphery of the pallet, thereby forming a gap in the perimeter 104. While this may reduce the overall stiffness of the pallet, it allows the lower leg extensions to extend to the ends of the pallet, thereby more closely simulating the function of a non-nested pallet. Pallet rigidity may be maintained through the use of reinforcing beams 120 (shown here during insertion), which are typically formed of metal or a variety of reinforced polymer materials and are inserted along corresponding channels 122 along the length of the pallet 400. As an aside, such reinforcing beams and channels may also be advantageously used in the previously described embodiments, such as Figure 3A , 3F , 6B, 7A and 9B as shown in the non-limiting examples.

[0057] like Fig.10 As shown, during the nesting of the pallets, the portion of the struts 106 below the vertical overlap region is preferably formed into a closed shape (in the horizontal plane) to maintain most of the strength and rigidity of the strut structure.

[0058] Final Reference Figures 11A to 12B As an alternative to the plurality of rigid lower support extensions of the above-described embodiments, according to the teachings of certain embodiments of the present invention, trays 500 and 600 employ a displaceable lower support extension 510 or 610 to provide an extension ( Fig.11A and 12A ) and it retracts to nest the tray ( Fig. 11B and 12B ). In these cases, the upper strut opening of the previous embodiments is not required because the strut extension can be retracted to allow nesting. When the strut extension is retracted, it is contained within the internal volume of the strut, and a lower strut opening is required to allow the strut extension to protrude outward when deployed.

[0059] For tray 500, lower leg extension 510 is pivotally mounted on a pivot 512 and is spring-biased by spring 514 toward Fig.11A The lower leg extension 510 may be manually retracted for nesting, for example, by being held in its retracted state by a capture mechanism (not shown) that is released when nesting with an underlying tray so as to automatically deploy when the trays are separated. Alternatively, the shape of the extension and the corresponding surfaces of the leg may be such that the lower leg extension is mechanically displaced by the interaction of the two trays during the nesting process so as to be retracted without manual intervention.

[0060] For tray 600, lower leg extension 610 is slidably displaceable along a channel 612 defined by the tray legs under the bias of a spring 614. As with tray 500, the same options of manual retraction (with or without a catch mechanism) or retraction due to mechanical interaction between the trays during nesting are possible embodiments.

[0061] It should be understood that the above description is by way of example only and that many other embodiments are possible within the scope of the invention as defined by the appended claims.

Claims

1. A nestable pallet for supporting a load above a floor, characterized in that: The nestable pallet comprises: (a) a platform having an upper surface for supporting the load, the platform having an outer periphery; and (b) a plurality of hollow struts rigidly coupled to the platform and extending downwardly from the platform, to support the platform above the floor, each of the plurality of hollow posts having an upper opening and an inwardly tapering inner surface for receiving a portion of a corresponding post of another pallet when a plurality of similar pallets are stacked, wherein each of the plurality of hollow posts adjacent the periphery comprises a peripheral support arrangement, the peripheral support arrangement comprising: (i) a lower support extension projecting horizontally from an inwardly tapered portion of the support toward an edge of the tray corresponding to a downwardly projecting portion of the periphery, and (ii) an upper leg opening for receiving said lower leg extension of another pallet when a plurality of similar pallets are stacked.

2. The nestable pallet according to claim 1, characterized in that: The lower support column extension forms a closed-shaped portion of the lower portion of the support column.

3. The nestable pallet according to claim 1, characterized in that: The inwardly tapered portion of the strut has a taper angle of at least 3 degrees, and wherein the lower strut extension has a draft angle of no more than 2 degrees.

4. The nestable pallet according to claim 1, characterized in that: The perimeter of the platform is continuous around the platform, and wherein the lower leg extensions are sized to fit within the perimeter when a plurality of similar trays are stacked.

5. The nestable pallet according to claim 1, characterized in that: The inwardly tapered inner surface of each of the plurality of hollow struts defines a generally rectangular horizontal cross-sectional shape, and wherein at least one edge of the rectangular horizontal cross-sectional shape is interrupted by the upper strut opening and the lower strut extension, the lower strut extension extending beyond the rectangular horizontal cross-sectional shape.

6. The nestable pallet according to claim 1, wherein: At least one of the plurality of hollow pillars adjacent a corner of the platform is formed with two of the peripheral support arrangements extending toward two adjacent edges of the tray.

7. The nestable pallet according to claim 1, wherein: The plurality of hollow pillars are integrally formed with the platform.

8. The nestable pallet according to claim 1, wherein: The plurality of hollow struts are mechanically attached to the platform.

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