This invention claims the benefit under 35 U.S.C. § 119 of Mexican Application No. PA/a/2004/000921 filed Jan. 28, 2004, which is herein incorporated by reference in its entirety.
The present invention relates to stackable containers and more specifically to stackable trays for storing or transporting articles or products with different dimensions, which trays may be oriented and safely placed on top of each other in accordance with the dimensions of the product or article to be stored or transported.
It is known that one of the principal problems that currently exist in warehouses or transport vehicles is that of the space required to store or transport the largest possible quantity of articles or products without damaging them. Accordingly, users have developed, or have asked companies that are experts in the field to design, receptacles or containers that, depending on their needs, will allow them to store or transport their products or articles safely.
It is widely known in the field of packaging, storage, and transportation that space is saved when receptacles or containers are stowed or stacked. However, in order for stowing or stacking to be performed, consideration must be given to the subsequent handling of the receptacles or containers and to the type of articles or products that will be stored or transported in them, as well as to the subsequent storage and transport of the empty containers or receptacles. Some of the many factors that have been considered in the design of such receptacles or containers include the height of the articles or products to be stored, transported, or distributed; the weight of the product that the receptacle or container must bear; the characteristics of the place or places in which the articles or products will be stored, transported, or distributed; the conditions under which they will be handled by the operator or seller; the conditions of the road over which they will be transported; and their subsequent stacking after they have been emptied, including cleaning and washing, etc. One of the principal techniques that have been used for the stacking of receptacles or containers is the so-called “nesting” technique, which consists of stacking the receptacles or containers at different angles so as to achieve a minimum height and a maximum height (see, for example, U.S. Pat. No. 3,780,905, of Ralph H. Herotzer; U.S. Pat. No. 3,934,724, of Lewis T. Johnson; U.S. Pat. No. 4,577,759, Pinckney Molded Plastics, Inc.; and U.S. Pat. No. 4,320,837, of James C. Carrol et al.).
U.S. Pat. No. 4,936,458, of Tabler et al., describes a tray that can be nested at 90°, or stacked at 0° or 180°, through the use of feet and rails, and also describes a possible so-called “blind” stacking through the cooperation of insertion elements. It also describes the use of trays of different heights for stacking; however, it does not address the crosswise nesting of trays of different heights.
U.S. Pat. No. 6,394,274, of Pinckney Molded Plastics, Inc. (Howell, Mich.), describes a bread tray that can be stacked on an identical tray that provides three levels of storage, which are obtained by rotating the trays to a given angle, depending on whether they are to be nested or stacked. This patent does address crosswise stacking. However, this patent has the disadvantage that when sudden movements occur due to handling by the operator, the upper trays are easily separated from the lower trays, thereby causing damage to the product and rendering it unacceptable to the purchaser. Moreover, the trays have a very short sliding groove, which does not allow rapid alignment during the sliding operation, and also causes the trays easily to become separated. The trays include handholds that can injure the operators or that simply are not convenient for the operators in terms of proper handling of the trays, and that are not designed to withstand rough handling by the operators or the conditions that are present in trucks when they encounter potholes, earthfills, winding roads, etc. The result is that their useful lifetime is reduced significantly, and that the trays become separated while being transported by such trucks, which can cause damage to, and rejection of, the transported products. The marks that the trays may contain in order to indicate to the operator the angle at which they are stacked tend to disappear rapidly as a result of the daily use and frequent cleaning that the tray must undergo, especially when the tray is used to transport food products that demand minimum levels of hygiene, thereby causing the operator to spend additional time determining whether a tray is stacked or nested. All of the above-mentioned trays have slots or small openings in the sides in which small amounts of the product can become lodged and can decompose, and sometimes these slots or openings can even lead to substandard cleaning of the tray. It should be noted that because of its design, it may not be possible for such a tray to be handled by an individual who has a disability or handicap. The stop elements that are used when the tray is placed in the crosswise position are not sufficient to prevent the tray from departing from its so-called “stable” position, with the result that some products are damaged when they fall off the tray. Furthermore, this tray does not have a male-female socket which, in the stacked position, allows the upper tray to be affixed securely to the lower tray. Yet furthermore, the design of this tray does not allow a tray of a different width to be stacked on top of a lower tray, and does not contemplate the combination or alternation of trays of different widths during stacking.
An additional disadvantage of the tray in U.S. Pat. No. 6,394,274 is that it runs the risk that the groove or sliding guide for the feet, as well as the sides and handholds, may become deformed or break within a short period of time, because of rough handling by the operator or even because of the weight of the product plus the weight of each stacked tray.
Another disadvantage of the trays in the prior art is that there is a risk that the trays will be overturned if, for example, an operator accidentally leans against the trays, because there is no balancing support on one side of the trays. Moreover, the height of the space between one tray and the next changes when the trays are rotated in order to shift from a nested position to the stacked position.
The present invention is intended to solve the above-mentioned problems. Thus, one goal of the invention is to provide a receptacle or container, specifically, a stackable or nestable tray, for the storage or transport of the tray itself or of products to be stored or transported on the tray, that has a long useful lifetime even under harsh working or handling conditions, which is achieved through a combination of structural elements, such as a sliding guide or groove, corners, male-female sockets, and chamfered corners, which combination avoids the concentration of stresses under a normal load or overload. In order to achieve this combination, consideration was given to the working conditions to which the trays would be subjected, such as dragging force, overload, the type of transport to be utilized, and the roads over which the trays would be transported, as well as careful or careless handling by various operators, including operators who may have a disability or handicap.
Another goal of the invention is to provide a receptacle or container or tray with handholds that are ergonomically (anatomically) designed, in order to provide greater comfort and safety for the operator, so that the product located on the tray receives better treatment during the handling of the tray. The design of these handholds includes a series of protective strips or ridges, which make the handholds more resistant to damage caused by dragging, thereby considerably increasing the useful lifetime of the trays.
Another goal of the present invention is to provide trays with differentiated handholds that allow the operator to identify, rapidly and easily, the proper side for stacking, stowing, or nesting the trays, as desired, including doing so simply by touch.
Yet another goal of the present invention is to provide the trays with a dual guide or groove in the base of the feet, similar to a so-called “shoe” or skate”, to provide better fitting and securing of the trays, thereby preventing them from becoming separated during rough or sudden movements while they are being stored or transported. The dual guide or groove is located along the length of the sides of the trays, so as to allow the feet to be displaced with greater safety, by preventing the trays from becoming separated or departing from their position during transport or handling, and also by preventing the feet of the tray from exerting a force that would deform the guide or groove, or even break it, because of the weight or overweight of the products that are received, held, transported, or lodged on the trays.
Yet another goal of the present invention is to provide a stackable or nestable tray that can be positioned crosswise on another tray and that can be handled by a person with a disability or handicap. This goal is achieved through the novel design of the tray, as described below.
Yet another goal of the present invention is to provide trays that are narrower (but without their narrowness being a limiting factor), that can be stacked on top of other trays that are wider, and that can also be combined or interleaved, in order to store products with smaller dimensions or different capacities.
With reference now to the figures,
As also shown in
These vertical ribs and reinforcements (6) significantly increase the mechanical strength of the cross-section of the handholds, thereby preventing the handhold from being deformed or even broken if the trays are pulled by a hook, either individually or in the form of towers, which is an extremely common practice in working yards. The approximate weight that can be supported by the tray according to the present invention, when located at the bottom of a tower of trays, before it is deformed or breaks, is approximately 410 to 420 kg.
The handholds (5) are differentiated from each other by their lower silhouette (7) (this is the surface that faces the flat surface on which the products are loaded; see
It should be noted that all of the internal lines (8) where the floor joins the sides and the corners are slightly rounded (
The structural elements (9) are designed to strengthen the tray and to conserve the amount of material used in the construction of the tray. It should be understood that multiple configurations of the structural elements (9) are possible.
The tray (1) has four handholds, one at each end of each side of greater height (3) (the trays available on the market have none). Two of them are approximately vertical (11) and are located very close to the edge, thereby allowing the user to identify, by touch, the side of the tray (that is, whether the tray is oriented in position to be stowed or stacked), and also to grasp the tray safely, comfortably, and easily, particularly when the tray must be lifted above the head of the user or operator, while the other two handholds are angled (12).
Because of their angle of attack, these inclined handholds (12) help the operator to differentiate and distinguish the orientation of the tray with respect to the tray immediately below it on which it will be placed, thus making it possible to determine whether in this direction the tray (1) should be stowed or else nested on top of a lower tray (see
Because of their angle, the inclined handholds (12) provide better support for the tray and its contents, help provide an appropriate lever arm when the trays are stowed or nested above the operator's eye level; allow sufficient force to be applied; and support the tray in cantilevered form during a maneuver in which a tray must be held by its ends and simultaneously aligned with another tray. This design of the handholds is also useful when trays must be handled in areas other than work yards or factory facilities (because trays often need to be loaded into, and repositioned inside, transport vehicles) and in areas that customarily have a limited amount of working room, which further complicates the tasks of stowing and nesting the trays (for example, inside a freight truck or a mini-van).
When the trays are “nested”, these vertical structural elements serve as a basic guide that, in addition to anchoring and positioning both of the trays (see
Operation of the Dual-Guide or Dual-Groove System
Four feet (in groups of two) are located on the sides of reduced height of the tray. These feet are different from each other in that two of them, which are located directly below the vertical groove of a side, serve as guide, support, and retaining elements. They form a set of dual and parallel shoes or skates, which, when they slide along the guides, serve first as a guide for maintaining the proper direction of the displacement of the upper tray when this tray is placed on top of a lower tray in order to be “stowed”.
These shoes or skates thus serve as buttresses, and take the load of the weight of the tray that is sliding on top of the tray immediately below it. The same thing also occurs with the single shoes or skates of the other two feet.
These dual shoes or skates also serve as limiting retention elements that prevent the deformation of the sides of the trays by “anchoring” and supporting them, and also prevent any unintended displacement, through a locking effect between the external shoe or skate and the internal rail. The foregoing mechanism is supplemented by the dual guide, which consists of two long and parallel elements, between and on which the above-mentioned shoes or skates act and interact.
Located along the length of the hollow formed by the rails are small “unidirectional lugs” (not shown on the drawings) which allow displacement only in one direction, thereby locking the feet in position once they have reached the end of their travel path.
The rear feet (i.e., the two that are located directly below the inclined handholds) play a role that is similar and complementary to that of the front feet, except that these feet are single instead of dual, inasmuch as, by being seated in their respective housings, they indicate when the trays are properly nested.
The heights and depths with which all of these elements have been designed are such as to ensure their stability, because they cannot be loosened or “bounced” out of their channels as the result of an undesired jolt, such as one caused by a pothole in a road or by rough-surfaced highways.
A further aim of the above-mentioned design is to ensure that the operator will be able to position the delivery, easily and rapidly, and ensure the smooth, continuous, and safe displacement of the parts of the tray that he is placing, in relation to the lower one, and also to ensure that it will be very difficult for multiple trays to be bounced apart or loosened, thereby causing breakage and loss of the product.
The design of the receptacles or containers or trays allows uniform working distances to be maintained when the receptacles or containers or trays are oriented differently in relation to one another. Thus, when the layout of the trays in relation to each other is changed, the separation between the trays does not affect or change the useful storage space that must be provided, which always remains the same. The foregoing observation is important because it enables confident planning of the arrangement and distribution of objects or products to be transported and stored, because when the useful available space is guaranteed, and when it is known that this space will not change, the planning for the distribution and storage of the products can be done beforehand.
Another important characteristic of the tray according to the present invention is the increased load capacity, which is achieved through the proper reinforcement and distribution of the ribs that form part of the structure of the four sides. The sides greater in height are the ones whose function is to bear the weight of the towers of trays full of products, and therefore have been designed such that, thanks to a system of ribs, they form a solid and rigid block that can support loads of up to 450 kg.
Regarding the form and design of the four corners, the sides of reduced height have been joined to the sides of greater height, thereby forming individual angles and joints that allow the corners to support loads of up to 250 kg, as well as the pulling loads applied during dragging, of up to 450 kg.
As mentioned above, the tray includes sides of reduced height that are modified by a broad curve that forms a wide window between the trays, when they are stacked or stowed, thereby allowing the contents of each tray to be viewed easily, with no need to raise them or lift them apart from each other in order to look inside them.
Although all of the fundamental characteristics and features of the present invention have been described here, with reference to specific embodiments of the invention, a degree of latitude in terms of other modifications, changes, and substitutions may be made in the foregoing description, and it will be apparent that on certain occasions, some of the characteristics of the invention will be employed without the corresponding use of other characteristics, without thereby departing from the scope of the invention as established. It should be understood that any such substitutions, modifications, or variations may be made by those skilled in the art without departing from the spirit or scope of the invention. Consequently, all modifications and variations are included within the scope of the invention, as defined by the following claims.
Number | Date | Country | Kind |
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PA/A/2004/000921 | Jan 2004 | MX | national |