MXPA00006691A - Plastic pallet - Google Patents

Abstract

An improved pallet made of a synthetic resin wherein the underside of the upper deck (10) is substantially planar, and the supports (50, 52, 54) which separate the upper and lower decks (10, 40) are integrally formed with and project upwardly from the lower deck (40), and are secured to the underside of the upper deck (10). The upper ends of the supports (50, 52, 54) are received in recesses (14, 16, 18) in the underside of the upper deck (10), and the recesses (14, 16, 18) and the supports (50, 52, 54) preferably have mating elements (20, 62) which snap-actingly engage one another to lock the supports (50, 52, 54) in the recesses (14, 16, 18) when the decks (10, 40) are assembled. Preferably, the supports (50, 52, 54) are tapered, the lower ends of the supports (50, 52, 54) being wider than the upper ends thereof.

Description

PLASTIC PIATAFOR A Field of the Invention The present invention relates to platforms for supporting loads, articles or other materials, and more particularly to a platform made of synthetic resin for use with a load elevator.

Background of the Invention The platforms made of molded plastic material have different advantages over those made of wood or metal. The wooden platforms are heavy; they are subjected to warping, chipping and crevice; they are not uniform in their resistance; and they increase significantly in weight when they get wet. Metal platforms are typically expensive and, in the case of steel, heavy and prone to corrosion. Plastic platforms, although stronger, lighter and more durable than wooden platforms, nevertheless have their own disadvantages. In an effort to minimize molding costs, some plastic platforms have been designed Ref.121420 as modular units which consist of a plurality of identical molded elements which are press fit, fused or otherwise secured together to make a complete platform. Examples of this type of platform are described in U.S. Pat. Nos. 4,051,787; 4,597,338; and 5,197,395. However this is a compromised scheme which usually gives a platform that is made of more material (and therefore heavier and has a stronger material cost) than could be required if the upper and lower portions of the platform they were optimally designed to serve their diverse purposes. Specifically, the upper deck of a platform must have relatively small openings to adequately support the load through the substantially complete upper surface of the platform; it must be sufficiently rigid (usually produced by substantial grooves) to prevent excessive bending, either when resting on the forks of a load elevator, or resting on the supports separating the upper and lower covers; and its upper surface must not have recesses or cracks that could collect water or dirt. The upper covers of the platforms described in the aforementioned patents have these characteristics. By contrast, the lower part of the platform, which is normally proposed to rest on a substantially solid surface, such as a floor, a roof, a shelf, or a frame, does not need to have so much material on its bottom side in contact with the surface of support. Accordingly, the lower cover of a plastic platform may have relatively large openings, and may have exposed ridges, recesses and cracks on its underside, since the design provides adequate support for the loaded platform. An upper deck deck which is inverted to serve as a lower deck could thus have more material than could actually be required to perform the functions of a lower deck. Figures 8-19 of U.S. Pat. No. 4,051,787 show the examples of a platform which has relatively large openings in its lower cover. However, the structure surrounding these openings appears to be very thick and bulky, with a large, closed, lower surface area that could make contact with a supporting surface. The lower cover may look like it contains more material than is actually required. Some platforms which comprise identical molded halves require a plurality of elements of securing separately to secure the halves together. The U.S. Patents Nos. 2,699,912 and 5,197,395 describe examples of these types of platforms. The use of separate securing elements introduces an increased cost and assembly time to the construction of the platform. Efforts to minimize the amount of plastic material used in a platform have led some to contemplate hybrid constructions where discrete reinforcing rods are integrated over the molded platform. An example is described in U.S. Pat. No. 4, 316,419, which uses metal reinforcing rods that are inserted into the channels molded on the platform. The problem with these types of platforms is that they require additional components manufactured separately and additional assembly steps. Another problem with plastic pallets is that their surfaces tend to be slippery. Measures must be taken to prevent the cargo from sliding off the platform; to prevent stacked platforms, whether loaded or not, from slipping into each other, and to prevent the platform from sliding out of the forks of the load elevator. Common anti-slip measures involve the use of anti-slip coatings or rubber inserts, such as as pads or washers, placed in strategic places. The examples are shown in Figures 20-25 of U.S. Pat. No. 4,051,787. A problem with these anti-slip measures is that they require the installation of additional parts or materials. In addition, non-slip coatings can tear, while inserts can loosen during work and fall off completely during use, rendering them ineffective. In the bottled beverage industry, full and capped bottles are placed in packages of bottle boards, which are loaded onto the platforms and moved from here to there using a load elevator. Table packings are typically of a shallow variety, such that the bottles are projected above the upper edges of the packagings of boards. Because the bottles are of uniform weight, it is desirable to apply several pallets loaded one on top of another so that they can be moved from here to collectively by a load elevator, and stored efficiently in a stacked configuration either on a floor or on a shelf or rack. The lower deck of the platform must be designed so that the load of a platform is distributed evenly over the closes the bottles on the underlying platform. Existing platform constructions do not adequately address this need.

Brief Description of the Invention Therefore, it is an object of the present invention to provide a durable, rigid plastic platform, which can be manufactured only from one type of material, without using an excessive amount of this material. It is another object of the invention to provide a plastic platform which comprises a minimum number of parts, and which does not require separate fasteners to secure the parts of the platform together, to simplify assembly of the platform. Another object of the invention is to provide a plastic platform which is suitable for use in the bottled beverage industry, allowing a loaded pallet to be stacked on and supported by bottles carried by an underlying pallet. A further object of the invention is to provide a plastic platform that possesses sufficient anti-slip properties in the regions of contact with the load, contact with the forks and support of the lower part, critical, without resorting to the application or fixing of various elements or anti-slip materials. These and other objects are achieved by providing an improved platform made of a synthetic resin wherein the underside of the upper cover is substantially flat, and the supports separating the upper and lower covers are integrally formed with and project upwards from the top. bottom cover, and are secured to the bottom side of the top cover. The upper ends of the supports are preferably received in recesses on the underside of the upper cover, and the recesses and supports preferably have casing elements which are pressed tightly together to fix the supports in the recesses when the covers are assembled. Preferably, the supports are tapered, the lower ends of the supports are wider than the upper ends thereof. The supports are hollow and have internal vertical reinforcement ribs which project inward from the side wall of the support.

In a preferred embodiment, the platform is rectangular and has nine supports, the longest of them located in the center, one located in each corner, and one located in the middle part of each side, to form a four-way platform which It can be coupled by a load elevator from either side. The lower cover comprises a rectangular perimeter base from which the perimeter supports are projected, and an X-shaped central base, formed integrally, from which the central support is projected, the central base that joins the perimeter base at the midpoint of each side thereof. These base portions define four large openings through the lower cover, and are preferably bevelled on their edges. The reinforcement ribs on the underside of the base portions are spaced more closely in the regions below the supports. In another aspect of the invention, an improved synthetic resin platform is provided, wherein the top surface of the top cover, the bottom surface of the bottom cover, and the bottom side of the top cover in the receiving regions of the Forks between the supports, have a rough texture resistant to sliding. Preferably the rough texture comprises a rough multidirectional configuration.

A preferred method for creating such rough configuration is by brushing the surfaces with at least one wire brush in the shape of a cup or cup.

Brief Description of the Drawings A preferred embodiment of the invention is described in detail below and is illustrated in the appended drawings, in which: Figure 1 is a top perspective view of a preferred embodiment of an assembled platform according to the invention; Figure 2 is a bottom perspective view of the platform of Figure 1; Figure 3 is a top plan view of the Figure 1; Figure 4 is a bottom plan view of the platform of Figure 1; Figure 5 is a side elevational view of the platform of Figure 1, all sides are identical; Figure 6 is an exploded view, in top perspective, of the platform of Figure 1, showing the upper and lower covers juxtaposed for assembly; Figure 7 is an exploded view, in perspective below, of the platform of Figure 6; Figure 8 is an exploded view, in lateral elevation, of the platform of Figure 6; Figure 9 is a top perspective view of the upper deck of the platform of Figure 6; Figure 10 is a bottom perspective view of the upper platform of Figure 9; Figure 11 is a top plan view of the upper cover of Figure 9; Figure 12 is a bottom plan view of the top cover of Figure 9; Figure 13 is a top perspective view of the lower cover of the platform of Figure 6; Figure 14 is a bottom perspective view of the lower cover of Figure 13; Figure 15 is a top plan view of the lower cover of Figure 13; Figure 16 is a bottom plan view of the lower cover of Figure 13; Figure 17 is a partial sectional view taken along line 17-17 in Figure 1; Figure 18 is a partial sectional view taken along line 18-18 in Figure 6; Y Figure 19 is a schematic perspective view of a method for roughening the selected surfaces of the platform.

Detailed description The platform consists of two separately molded parts - an upper cover 10 and a lower cover 40 - which are injection molded from a suitable synthetic ream, such as high density polyethylene, polypropylene, or filled polypropylene. In the plan view, the platform is square, with rounded corners, and has a symmetry of four shapes or ways. As explained in more detail below, the two covers are adapted to be easily snapped together to form the finished platform illustrated in Figures 1-5. Figures 6-8 illustrate how the two covers are aligned for assembly. To provide greater rigidity, the covers can be permanently welded together using any known resin welding technique. Figures 9-12 show the upper cover 10. This cover has a solid upper surface 12 interrupted by a series of triangular holes 15, which reduce the weight- of the cover and allow drainage in the event that the platform becomes wet. Referring to Figures 10 and 12, a series of ridges are formed on the underside of the top cover 10. Some of these ridges form a square, central recess 14 with rounded corners. Other ridges form a circular recess 16 in each corner of the cover. Still other ridges form oblong recesses 18 with rounded ends at the midpoint of each side of the cover. As described below, these nine recesses are adapted to receive the upper ends of the nine supports which are integrally molded with the lower cover 40. The areas between the recesses are regions for the reception of the forks which are proposed to rest on the forks of a load elevator that can couple the platform from either side. Other flanges on the underside of the upper cover 10 form an orthogonal configuration which runs parallel and perpendicular to the sides of the cover, while still other flanges form another orthogonal configuration that is set at 45 ° with respect to the first configuration. These ridges collectively form structures similar to a master beam, interconnected, which extend the spaces between the recesses 14, 16 and 18 for receiving the support. As can be seen in Figure 8, the underside of the upper cover 10 is substantially planar, that is, substantially all of the flanges on its underside end in a common plane. In each of the recesses 14, 16, 18 are four dependent snap-fit tabs 20. The details of the snap-fit lugs 20 can be seen in Figures 17 and 18. Each has a flexible leg portion 22 and a tapered tip 24 with a projection 26 which snaps under or a lip of the support of the lower cover 40. Adjacent to each snap-fit lug 20 in the recesses 16 of the circular corner, is a small arcuate slot or hole 28. A similar but rectangular slot or hole 30 lies adjacent to each lug of pressure adjustment 20 in the other recesses 14, 18. The slots 28, 30 facilitate the formation of the press fit tabs during the molding operation, and also allow the insertion of a separation tool which can be used to press Press fit tabs and separate top and bottom covers if desired.

The lower cover 40 has a perimeter which substantially corresponds to the perimeter of the upper cover 10. Referring to Figures 13-16, the lower cover 40 comprises a rectangular perimeter base 42 and an integrally formed X-shaped central base 44. . The bases 42 and 44 have beveled edges 46, and oblong openings 48. Four corner supports 50 project upwardly from the lower cover 40 at the corners thereof. The supports 50 have a circular cross section and a truncated cone shape, with the base being wider than the top. Four middle side supports 52 project upwards from the sides of the perimeter base 42. The side supports 52 are oblong in cross section with rounded ends, and are also tapered, with the widest portion at the bottom. A large central support 54 projects upwardly from the center of the central base 44. The central support 54 has a generally square cross section with rounded corners, and is also tapered with the wider portion at the bottom. The corners of the central support 54 protrude towards the large openings 56 in the lower cover 40 which are defined by the intersecting base portions 42, 44.

Each support 50, 52, 54 is hollow, and has internal vertical reinforcement ribs 60, which project inwardly from the side wall of the support. The upper end of each support is rotated inward to form a horizontal peripheral lip or edge 62. Referring to Figures 17 and 18, when the upper and lower covers are pressed together during assembly, the inclined portion 24 of each tab for the Press fit 20 travels past the lip or lip 62, causing the press fit tab to bend inward. When the projection 26 clears or frees the lip or edge 62, the press-fit tab snaps or jumps outwardly to be captured under the lip or edge 62. As can be seen in Figures 14 and 16, the bottom side of the lower cover 40 has several series of reinforcing beads which provide structural rigidity to the base portions 42, 44 and appropriately distribute the load carried by the upper cover 10 and the supports 50, 52, 54. In the regions which underlie on the supports, the grooving is spaced more closely than anywhere in the base portions. This arrangement distributes the load better from the top of the platform, and also makes the platform more suitable for use in the industry. bottled beverages, where a loaded platform can be placed directly on the top of the closures of the bottle, bottles carried by another platform. All spaces between the ridges on the underside of the lower cover 40 are sized to prevent the smaller bottle closures (approximately 28 mm) from being adjusted or snapping between the flanges. The synthetic resin used to form the platform typically has a rather slippery surface finish when the platform is new. This is undesirable in certain critical areas, namely, the upper part of the upper cover 10, the lower side of the lower platform 40, and the underside of the upper cover 10 in the regions between the supports, which rests on the forks of a load elevator. According to the invention (see Figure 19), these critical areas are subjected to a non-slip treatment which comprises brushing with a wire brush of the surfaces S, preferably with at least one wire brush B in the shape of a cup or cup, rotating, to produce a rough surface that has a multidirectional roughness configuration. This is done before the upper and lower covers are joined together. The anti-slip characteristics of this surface - ^^^ - Rough does not appear to degrade over time because the normal use and handling of the platform seems to subject the surfaces to an additional roughness treatment when the platform is loaded, unloaded, and moved from here to there. The advantages of the platform according to the invention will be readily apparent to those skilled in the art. The symmetrical two-piece injection molded plastic construction produces a substantially durable and durable assembly, simple construction, and easy handling. The snap-fit lugs 20 are protected from damage prior to assembly because they are recessed in the top cover. A substantial amount of the open area strategically placed within the structure minimizes the amount of material required, without understanding the structural rigidity. The tapered shape of the supports allows for easy mounting, and good dispersion of the load from the top cover to the bottom cover. The supports have rounded, smooth outer sides to prevent damage from the forks of a load elevator. The upper cover completely covers the supports, preventing debris from being collected in the hollow areas. The platform is easy to keep clean and washed because all the flanges of exposed support are on the underside of both covers, and there are no cracks that collect dirt or water. The bottom part of the bottom cover is designed to transfer the load evenly to the bottle closures when the pallets loaded with the bottles for the beverage are stacked together. In particular, the critical load areas under the supports are strongly reinforced with a maximum surface area to uniformly load the bottle layer on the bottom platform. Finally, the treatment of the surface to give it roughness, to give an anti-slip effect, is a simple, long-lasting and reliable solution to the problem of sliding of the covers and the surfaces that make contact with the forks. Although a square platform has been illustrated and described in the preferred embodiment, other forms, for example, rectangular, could be possible as long as they still take shape in the features of the invention. The cross-sectional shapes of the supports 50, 52, 54 may also vary somewhat from those shown. Other modifications will be apparent to those skilled in the art without departing from the spirit and scope of the invention, which is limited only by the appended claims.

It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it relates.

Having described the invention as above, property is claimed as contained in the following

Claims (20)

1. In an improved synthetic resin platform, for use with a load elevator, comprising separately molded upper and lower covers, spaced apart by a plurality of supports to define between them the hairpin receiving regions under the upper cover, the improvement is characterized in that a bottom side of the top cover is substantially planar, and the supports are integrally formed with, and project up from, the bottom cover and are secured to the underside of the top cover, wherein each one of the supports is tapered and includes a lower end and an upper end, the lower end of each support is wider than the upper end thereof.

2. A platform according to claim 1, characterized in that the upper ends of the supports are received in the recesses on the underside of the upper cover.

3. A platform according to claim 2, characterized in that the recesses and the Supports have integrally formed casing elements which engage with each other in a pressurized closed manner to fix the supports in the recesses when the upper and lower covers are assembled.

4. A platform according to claim 1, characterized in that one of the supports is located substantially in the center of the platform, and the other supports are located substantially on the periphery of the platform, the central support is the largest support.

5. A platform according to claim 4, characterized in that the platform is generally rectangular with nine supports between the covers, a support is located in each corner of the platform, and a support that is located in the middle part of each side of the platform , the supports define two regions for the reception of the forks, so that the forks are introduced from each side of the platform.

6. A platform according to claim 5, characterized in that the lower cover comprises a generally rectangular perimeter base from which the peripheral supports are projected, and an integrally formed X-shaped central base, from which the central support is projected, the central base that joins with the base of the perimeter in the middle part of each side of the same.

7. A platform according to claim 6, characterized in that the base of the perimeter and the central base define four large openings through the lower cover.

8. A platform according to claim 1, characterized in that each of the supports is hollow, has a side wall, and has inside it vertical reinforcing ridges which project inwards from the side wall.

9. In an improved synthetic resin platform, for use with a load elevator, comprising separately molded upper and lower covers, spaced apart by a plurality of supports to define between them the regions for receiving the forks under the upper cover , the improvement is characterized in that one underside of the upper platform is substantially flat, and the supports are formed integrally with, and project upward from, the lower cover and are secured to the underside of the upper cover, the supports have lower ends and upper ends, the upper ends of the supports are received in the recesses in the On the underside of the upper cover, where the supports are tapered, the lower ends of the supports are wider than the upper ends thereof.

10. A platform according to claim 9, characterized in that each of the supports is hollow, has a side wall, and has inside it vertical reinforcing ridges which project inwards from the side wall.

11. In an improved synthetic resin platform, for use with a load elevator, comprising separately molded upper and lower covers, spaced apart by a plurality of nine supports to define between them the regions for reception of the forks under the cover superior, the improvement is characterized in that the bottom side of the upper platform is substantially flat, and the supports are formed integrally with, and project upward from the lower cover and are secured to the underside of the upper cover, one of the supports is located substantially in the center of the platform, and the other supports are located substantially on the periphery of the platform, the central support is the largest support, where the platform is generally rectangular, a support is located at each corner of the platform, and a support is located at the midpoint of each side of the platform, the supports define two of the regions for the receiving the forks, so that the forks are introduced from each side of the platform, the lower platform includes a rectangular perimeter base from which the peripheral supports are projected, and a central X-shaped base formed integrally from the which is projected the central support, the central base joins the base of the perimeter at the midpoint of each side of it, the base of the perimeter and the central base define four large openings through the lower cover, and wherein the portions of the central support protrude towards the large openings.

12. A platform according to claim 11, characterized in that the underside of the base of the perimeter and the underside of the central base have reinforcement ribs, some of the reinforcement ribs lie beneath the supports, the reinforcement ribs under the supports are more closely spaced than anywhere in the base of the base. perimeter and the central base.

13. A platform according to claim 11, characterized in that the corner supports are of circular cross section, the intermediate side supports are oblong in cross section with rounded ends in the areas adjacent to the fork reception regions, and the Central support is rectangular in its cross section with rounded corners.

14. A platform according to claim 13, characterized in that the supports are tapered, the lower ends of the supports are wider than the upper ends thereof.

15. A platform according to claim 14, characterized in that the upper part of the base of the perimeter and the upper part of the central base have beveled edges.

16. A platform according to claim 14, characterized in that each of the supports is hollow, has a side wall, and has internal reinforcement ribs projecting inwardly from the side wall.

17. A platform according to claim 13, characterized in that the upper part of the base of the perimeter and the upper part of the central base have beveled edges.

18. A platform of synthetic resin, for use with a load elevator, having upper and lower covers spaced apart by a plurality of supports to define between the same regions for reception of the forks under the upper cover, the platform is characterized because it is done by means of a method comprising: (a) molding the upper and lower covers separately from synthetic resin; (b) mechanically roughening a top surface of the top cover, a bottom surface of the bottom cover, and a bottom side of the top cover in the regions for reception of the forks, to create a rough texture resistant to sliding; and (c) assembling the covers to form a text platform.

19. A platform according to claim 18, characterized in that the step of providing roughness by mechanical means comprises roughening the surfaces to create a rough multidirectional configuration.

20. A platform according to claim 19, characterized by the step of providing roughness by mechanical means comprises brushing the surfaces with at least one wire brush in the shape of a cup or cup.