Patent Publication Number: US-5830299-A

Title: Method for manufacturing loading platforms with replaceable feet, and platform manufactured with said procedure

Description:
This invention is related to a method for manufacturing loading platforms fitted with replaceable feet, although the method is likewise applicable to platforms fitted with fixed feet. This invention also relates to a platform manufactured with the use of said method. 
     BACKGROUND OF THE INVENTION 
     Patent No. ES-9500892 and addendum No. ES-9502178 (corresponding to patent PTC/ES96/00100) refer to a loading platform comprising one or more mutually bonded layers, advantageously made of cardboard and provided with evenly distributed openings, the openings in each layer corresponding to those of the remaining layers, on which layers feet are dismountably assembled, advantageously in the shape of a truncated cone and provided with a peripheral lug optionally fitted with an interruption having two opposite slanting edges in the form of a ramp to facilitate the insertion in and removal from an internal space located between two layers which configure the cardboard or similar material platform through a notch provided in the openings of the layer located on the platform of the lower side, through which the lug of the corresponding foot may be inserted or removed. The intermediate layer openings are larger than the openings in the upper and lower layers, although similar, thus enabling the formation of the above-mentioned internal space. 
     The manufacture of this type of platform has normally been implemented by the use artisan, low-profit methods, one of the main drawbacks consisting in the manual assembly of each platform foot after forming the mutually bonded layer structure, which results in excessive platform production times. 
     DESCRIPTION OF THE INVENTION 
     In order to overcome these drawbacks, a manufacturing method has been devised which is the object of the present application. 
     The method of the invention is characterized in that at least one first layer, the openings of which have already been die cut, is arranged on a work bench acting as a supporting block provided with cavities which coincide with the layer openings in the intended platform and having a width and depth that allows the insertion of the platform feet, the peripheral lugs of which act as an abutment means against the first layer upon inserting the feet. At least a second layer is then bonded onto the first layer, its openings coinciding with those of the first layer. The contour of the second layer openings is equivalent to that of the radial lugs in the feet. At least a third layer is then bonded onto the second layer, its openings coinciding with those of the previous layers. The openings of this third layer are equivalent to those of the first layer. The assembly is then placed under a press that consolidates the adhesion between the various layers, whereby the peripheral lugs in the feet end up at the height of an intermediate layer, e.g. the second layer, thus trapped between the adjacent upper and lower layers. 
     By virtue of the method of the invention, platforms can be produced with a considerably lower time consumption than that employed by artisan means. This is mainly due to the fact that the feet are installed immediately after placing the first layer on the work bench and before bonding the second layer over said first layer, thereby avoiding the subsequent manual installation of the feet. 
     It has foreseen the possibility of manufacture several piled-up platforms simultaneously. Thus, once the layers are overlaid and bonded, with the feet incorporated in the corresponding openings which constitute a platform, the same method is repeated by piling up successive groups of layers and their corresponding feet which are then inserted in the feet of the platform immediately below, the whole assembly then being submitted to the action of a press which consolidates the adhesion of the bonded layers in each platform. 
     In order to facilitate voluntary removal of the feet from the platform, after installing them in the course of the manufacturing process, the interruption in the peripheral lug is made to coincide with the notch in the corresponding opening in the lower layer. 
     The loading platform manufactured by the method of the invention is characterized in that each foot comprises on its side surface a plurality of reinforcement nerves formed as from said side surface. 
     According to a first preferred embodiment, the feet are elliptic in cross-section, with a plurality of undulations being provided which define the reinforcement nerves. 
     According to a second preferred embodiment, the feet are oblong in cross-section, said shape being defined by two semi-circumferences linked by two respective straight portions, with a plurality of undulations being provided which define the reinforcement nerves. 
     Advantageously, the feet comprise a radial lug with a U-shaped contour, the smaller side of the lug being bevelled and the opposite side of the lug being interrupted by a ramp formed on the end thereof. The bevelled smaller side of the lug makes easier the introduction of the foot. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In order to better understand the description contained in this specification, drawings are attached which, merely by way of example, reflect a practical case of an embodiment of said method and platform. 
     In said drawings, FIG. 1 is a perspective view showing a work bench or supporting block and three separate layers designated in the description as the first, second and third layers, according to the order in which they are placed on the work bench; this same figure shows the platform feet located between the first and second layers; furthermore, this figure shows an enlarged detail of a corner of the first layer and a foot; 
     FIGS. 2-6 show longitudinal section views of subsequent platform manufacturing stages; 
     FIG. 7 is a view similar to the previous views, showing two platforms piled on the work bench; 
     FIG. 8 is a perspective view of a first alternative embodiment of the feet, wherein the various holes in the layers forming the platforms are also shown; and 
     FIGS. 9 and 10 are perspective views of a second and third alternative embodiments of the feet. 
    
    
     DESCRIPTION OF A PREFERRED EMBODIMENT 
     The manufacturing method of the loading platform fitted with replaceable feet consists--according to the example shown in the drawings--in the use of a work bench or supporting block 1 provided with several evenly distributed cavities 2, on which bench is deposited a first known layer 3 made of cardboard, &#34;tablex&#34; or some similar material having a some stiffness and provided with openings 4 of a diameter equivalent to that of the cavities 2 in bench 1, with which they are required to coincide. These openings 4 present respective notches 4a, the object of which is described further on. Advantageously, the lower side of layer 3 is impervious to water (FIGS. 2 and 3). 
     Truncated cone-shaped, hollow feet 5 are then inserted through the openings 4 in plate 3, in such a way that they lodge mainly within the cavities 2 in the bench 1. Said feet 5 are fitted with an open upper base 5b having an adjacent peripheral lug 6 with an interruption or notch 6a, the ends thereof forming ramps or bevels the original position of which coincides with that of notch 4a. 
     Thus, once the platform is obtained, the feet 5 are suitably positioned for removal at will, as described in patent PCT/ES/9600100. 
     Lug 6 has a diameter that is greater than that of opening 4, thereby providing a stop over layer 3 and limiting the insertion of foot 5 in cavity 2 (FIGS. 3 and 4). 
     The following stage of the method involves depositing a second layer 7, of a nature equal or similar to that of layer 3, both faces of which are covered with glue or adhesive. This second layer is provided with openings 8 of a diameter equivalent to that of the peripheral lug 6 of feet 5, the lug being thus surrounded by the corresponding opening 8. The upper base 5b in each foot projects slightly respect to layer 7 (FIGS. 4 and 5). 
     Over layer 7 is deposited a third layer 9 that is equal or similar to the first layer 3, is fitted with openings 10 having the same diameter as that of openings 4--although devoid of a notch, its upper face being impervious to water--and has a contour that is equivalent to that of base 5b of feet 5, so that said base is flush or coplanar in respect to layer 9 (FIGS. 5 and 6). The loading platform manufacturing method ends with the pressing of the layer assembly 3, 7, 9 with a conventional press 11 (FIG. 6) designed to bond the layers to one another, the lugs 6 of feet 5 remaining trapped between plates 3, 9 and the feet being thus incorporated to the bonded layer assembly which constitutes a platform 12. 
     The number of layers forming each platform may vary; however, the manufacturing procedure is basically as described. 
     Using this same process, and by repeating the stages described, groups of platforms 12 can be manufactured by superimposing the layers in the described order and intercalating the feet 5 between corresponding layers, so that the feet in each layer are inserted in those of the lower layer, then proceeding to the final pressing of a group of platforms 12, the example illustrated in FIG. 2 of the drawings showing only two, although their number could be increased. 
     FIG. 8 shows a first alternative embodiment of the feet 110, which is not object of the present invention. This embodiment is included in patent PCT/ES/9600100 and is described in this application to indicate that alternative feet exist other than those shown in FIGS. 1-7, which may be inserted in the holes in a different way, as explained in said patent, said insertion being made only when one of the feet has to be replaced, in view that, according to the method of the invention, feet 5, 110, 210, 310 are installed before bonding the second layer 7 onto the first layer 3. 
     The feet 110 are fitted with a radial lug 111 having a U-shaped contour which surrounds the two larger sides and one of the smaller sides in the foot of the upper base. The edge in the lug of the smaller side has a beveled edge 113 designed to facilitate the entry in space 109 of the notches 108. The lug is interrupted in its opposite side, its ends forming a ramp or skid 113a which facilitates removal of the lug in the event of having to replace the foot. 
     FIGS. 9 and 10 show alternative embodiments of feet 210, 310, their side surfaces comprising a plurality of reinforcement nerves 210a, 310a formed on said lateral surface. Said feet 210, 310 have an elliptic shape with a plurality of undulations which define the reinforcement nerves 210a, 310a. 
     Feet 210, 310 are fitted with a radial lug 211, 311 having a U-shaped contour which surrounds the two larger sides and one of the smaller sides in the foot&#39;s upper base. The edge in the lug of the smaller side is a beveled edge 213, 313, the lug being interrupted in its opposite side and its ends forming a ramp or skid 213a, 313a which facilitates removal of the lug in the event of having to replace the foot, as in the case of the feet previously described. The bevelled smaller side of the lug makes easier the introduction of the foot. 
     The system for inserting the feet 210, 310 in this second alternative embodiment is the same as that for feet 110 in the first alternative embodiment, as described in detail in patent PCT/ES/9600100. 
     The materials comprised in the various platform layers and the number of layers involved in each platform are independent from the essential object of the invention. The number and distribution of the platform feet may also be varied. Likewise, the method of the invention may be conducted in an automated manner, using layer supplying mechanisms for sequentially depositing the layers on the work bench 1 and for intercalating feet 5, 110, 210, 310 at the precise moment, namely before bonding the second layer 7 onto the first layer 3, ending with the final pressing of one or more layer groups.