Abstract:
A large-area protective covering system for installation in a staggered or grid configuration is provided comprised of a plurality of essentially identical large-area panels with honeycomb internal structures which have locking systems on the sides and ends for locking the panels in place. The panels, once locked together, have little movement along their x, y or z axis.

Description:
FIELD OF THE INVENTION 
   The present invention is directed to a product for the creation of temporary, protective surface cover, and the like, and in particular, to the protection of surfaces, such as ice in a hockey arena, artificial turf in a sports arena, and grass or other surfaces in indoor and outdoor venues. 
   BACKGROUND OF THE INVENTION 
   Covers for the protection of surfaces are commonly used to protect the ice surface in a hockey arena, for protection of artificial turf surfaces in indoor or outdoor stadiums, or to provide a modified surface other than, for example, concrete and the like, for both indoor and outdoor environments. 
   The prior art protective covering systems can include simple systems such as, for example, 4 by 8 foot sheets of plywood which are laid on the surface to be protected. A feature of this type of protective covering system is that it can be rapidly installed over a large surface, and thus allow for rapid conversion of, for example, the ice surface in a hockey arena, to allow for seating, for a concert or the like. The protective covering material can also be collected after use, stored, and reused in order to minimize costs. Further, the plywood sheets can be custom cut and saved to fit into areas of restrictive application, such as in the rounded corners of a hockey ice sheet. 
   However, use of simple plywood systems can lead to bending, shifting and buckling of the plywood, particularly if equipment, such as fork lifts or the like, are driven on the plywood surface. This can lead to the formation of small gaps between the plywood sheets which can cause tripping hazards, or which can trap the wheels of dollies or other equipment traveling over the protective covering surface. Use of tongue and groove plywood might overcome some of these problems, but this material would not be suitable for all applications since this system could not be rapidly or easily installed, and the tongue and groove feature could be easily damaged during routine installation or removal. 
   A further problem with this type of system is that it provides little if any significant insulation. This can be an important considerations if the protective surface is installed over an ice surface, or frozen wet ground where it would be desirable to provide a warmer floor temperature for those using the arena or site and provide for reduced cooling costs for maintaining the ice surface temperature under the protective covering. 
   Small-area systems are also known, having panels which are typically less than 5 square feet in surface area. Because of their small size, installation of these systems can take considerable time. Accordingly, it is generally preferred to use “large-area” panels each of which has a surface area of at least 10 sq. ft. 
   In U.S. Pat. No. 3,870,587 (Merrell), an ice rink cover is described having an insulated core, a wooden frame, and a simple “hand holds” to facilitate lifting and movement of the panes. Staten et al., in U.S. Pat. No. 5,820,798 and related U.S. Pat. No. 5,983,584, describe an ice rink cover which is produced by combining two identical plastic panels to form a combined protective covering panel which has an internal support structure consisting of aligned pillars from the upper and lower panel surfaces. 
   Accordingly, while the prior art systems have adequate protective covering properties, it would be advantageous to provide a large-area protective panel which would provide improved protective covering properties, while facilitating installation and removal of the protective covering. 
   SUMMARY OF THE INVENTION 
   Accordingly, it is an advantage of the present invention to provide a large area protective covering which can be used on various surfaces, such as ice sheets, turf, grass, pavement and the like. 
   It is a further advantage of the present invention to provide a large area protective covering system which can be installed and removed rapidly. 
   It is a further advantage of the present invention to provide a large area protective covering system which resists the tendency to bend, buckle or separate. 
   The advantages set out hereinabove, as well as other objects and goals inherent thereto, are at least partially or fully provided by the large-area protective covering system of the present invention, as set out herein below. 
   Accordingly, in one aspect, the present invention provides a large-area protective covering system comprising: a plurality of large-area panels wherein each of the panels comprises: a flat upper surface; a grid-pattern internal structure preferably attached to the upper surface; an optional flat lower surface; a first side having a first side-locking system; a second side having a second side-locking system, for operative engagement with the first side-locking system of an adjacent panel; a first end having an first end-locking system; a second end having a second end-locking system, for operative engagement with the first end-locking system of an adjacent panel. 
   The grid-pattern internal structure provides enhanced weight distribution and strength to the panels and the side-locking and end-locking systems on each of the panels are positioned so as to permit adjacent panels to be locked together. 
   Preferably, the first and second sides of the panel have a plurality of locking systems. Preferably each panel has at least 2 locking systems, more preferably between 2 and 5 locking systems, and most preferably, between 2 and 4 locking systems. 
   In a still further aspect, the present invention also provides a method for protecting a surface comprising installing a plurality of essentially identical large area panels each of which large-area panels are as hereinabove described. Preferably, however, the method for protecting a surface comprises installation of a plurality of essentially identical large area panels, each of which large area panels has an essentially flat upper surface; a grid-pattern internal structure; an optional essentially flat lower surface; a first side having a first side-locking system; a second side having a second side-locking system; a first end having an first end-locking system; and a second end having a second, end locking system. 
   The installation comprises: a) placing a first panel on a surface to be protected; b) installing a second panel with the first, end locking system of one panel in operative contact with the second, end locking system of the second panel, and sliding the second panel until the ends of the two panels are in contiguous contact with each other and the sides of the panels are essentially in alignment with one another; c) repeating step b) as often as required to establish an end-to-end row of large area panels which are in end-to-end alignment with each other; d) installing a further panel by placing the first, side locking system of the further panel in operative contact with the side locking system of the panels of the end-to-end row of large area panels, wherein the further panel is in side-to-side alignment with the end of any of the panels of the adjacent end-to-end row of large area panels; e) installing an additional panel by repeating step d) and by placing the first, end locking system in operative contact with the second, end locking system of the further panel; f) repeating step e) as often as required to establish a second end-to-end row of large area panels adjacent to the first end-to-end row of large area panels; and g) repeating steps d) to f) in order to establish a series of end-to-end rows of large area panels, wherein each of the rows is operatively connected an adjacent end-to-end row of large area panels. 
   In the present application, the term “protective cover” refers to covering materials which are preferably used for covering and protecting a surface such as artificial turf, ice, concrete flooring, grass, or the like. 
   Further, the present application is primarily directed to the use of protective coverings. However, the skilled artisan will be aware that covering system of the present invention might also be used in a wide variety of applications. For example, the skilled artisan would be aware that the present application is equally applicable in other non-protective covering applications. As such, the protective covering may be used to minimize damage to the protected surface, or may simply be used to provide an alternative surface appearance or texture. For example, a softer plastic floor material or a panel covered with carpet material might be preferable to a concrete floor, even in situations where the concrete floor has little risk of being damaged. 
   With respect to the use of the panels, preferably, the edges (e.g. the sides and ends) of the panels, and/or the sides of the end-to-end rows of large area panels when installed as a complete protective covering, are in essentially contiguous contact with each other. As such, there are no significant gaps between panels, and the protective covering provides essentially complete coverage of the surface to be protected. 
   The term “large area” is used to describe panels having a surface area coverage of at least 10 square feet, more preferably greater than 20 sq. ft., and most preferably greater than 30 sq. ft. The panel can be any suitable shape including square, rectangular, or the like, provided that the sides and ends of the panels are adapted for contiguous alignment with adjacent panels, as described hereinbelow. A preferred size and shape for the large-area panels is a rectangle which measures about 4 ft. (1.2 m) by about 8 ft. (2.4 m). Another preferred size and shape is a rectangle which measures about 5 ft. (1.5 m) by about 10 ft. (3.1 m). 
   In a typical installation, a number of panels would be used, and this number might exceed 50, 75 or even 100 panels which are essentially identical in size, shape and configuration. Having identical panels allows the user to easily replace any damaged standard panels, and facilitates installation since any standard panel could be placed anywhere in the protective covering. It should be noted, however, that special sized or shaped panels could be separately kept in order to address any specific installation issues, such as, for example, the rounded corners of an ice hockey rink. 
   It is a feature of the present invention that the panels may be installed in both a staggered configuration or as a grid pattern where the sides and the ends of the panels are both in alignment with adjacent panels. The staggered configuration includes staggering either at the sides, at the ends or both. 
   The upper surface of the panel is preferably made of a plastic material, but can be made of any suitable material having the strength properties necessary for the intended application. Preferably, the panel is made primarily of polyethylene, polypropylene or the like, or made be fabricated from recycled plastic material. Blends of these materials, or these types of materials, are also possible. The overall upper structure of the upper surface is preferably flat, but might contain some texturizing structures for appearance or for functionality, such as to reduce the slipperiness of a smooth plastic panel. The upper surface might also be covered by additional material, such as, for example, carpeting, vinyl or wood veneers, or the like, to give the panel a desired appearance when installed. 
   The optional lower surface of the panel is also preferably made of plastic, and preferably is made of the same material as the upper surface. However, additional support materials might be added to the lower surface of the panel in order to strengthen the sides or ends of the panels. These support materials might also be made of plastic, but can be made of a ferrous or non-ferrous metal such as steel or aluminum. The lower surface is also preferably essentially flat so as to rest completely flat on the surface to be protected. 
   The panel also comprises an internal structure, preferably attached to the upper surface and separating it from the optional lower surface, when present. Preferably, this internal structure comprises a “honeycomb” structure of, for example, 2″ to 4″ squares, with a depth of 1″ to 2″. Rather than squares, the pattern could be made up of circles, triangles, pentagons, hexagons or other shapes, or a mixture thereof, that serve to increase the weight bearing capabilities of the upper surface, distribute the weight of any load that might be applied to the panels and increases the structural strength of the panels. Any such pattern is herein defined as a grid-pattern. The internal structure is also preferably made of plastic, and preferably made of the same plastic as the upper or lower surface. In one embodiment, the internal structure can be formed as part of, and in combination with, the lower, or more preferably, with the upper surface. 
   The internal structure preferably has grid-pattern in order to provide the necessary support between the upper and optional lower surface, while still reducing the overall weight of the panel. Further, the gap within each honeycomb of the grid-pattern can be filled with insulating material in order that the panel will have some insulating properties. Preferably, the panel contains sufficient insulation to provide an insulation “R-factor” of more than 1, preferably more than 2, and most preferably, more than 4. The insulation might be a foamed material such as polyurethane which is foamed in place in the honeycomb structure, or might be a solid or rigid Styrofoam™ type material which is pressed into place within the honeycomb. Such an insulated internal structure is particularly beneficial for ice surface or frozen ground/turf applications. 
   The insulative ability of the panel will be dependent, inter alia, on the type of insulation chosen, and the depth of the honeycomb structure. 
   The locking system on each side and end of the panels is preferably a locking mechanism which can act as a slidable locking mechanism, and preferably comprises a system where each panel has a groove and a projection which corresponds with, and operatively engages a corresponding projection and groove, respectively, on an adjacent panel. 
   For ease of reference, the sides of the panels are orientated in the “x” axis, by definition. The ends of the panel are orientated in the ‘y’ axis. Up or down movement of the panels, would therefore be in the “z” axis. 
   By providing a slidable locking mechanism, the ends of the panels can be temporary connected, and the panel then slid into end-to-end alignment by sliding one panel with respect to the other. Once the ends are connected, one panel can be moved in the y axis with respect to the other. Once the sides of the panels are jointed, the panels are restricted in their x, y or z movement, provided that the panels are kept flat (e.g. not tilted). 
   Accordingly, through the use of the locking system, a protective covering system is provided wherein movement of any of the panels in the x, y or z axis is made difficult. As such, each panel is locked into place, and any tendency of the system for bend, buckle or separate, is reduced. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     An embodiment of this invention will now be described by way of example only in association with the accompanying drawings in which: 
       FIG. 1  is a perspective, cut-away view of one corner of a large area panel in accordance with the present invention disclosing the optional lower surface and internal structure; 
       FIG. 2  is a rear view of a complete panel; 
       FIG. 3  is a top view of a complete panel; 
       FIG. 4  is a side view of a locking system; and 
       FIG. 5  is a top view of a protective covering system fabricated in a grid pattern using a plurality of panels. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The novel features which are believed to be characteristic of the present invention, as to its structure, organization, use and method of operation, together with further objectives and advantages thereof, will be better understood from the following drawings in which a presently preferred embodiment of the invention will now be illustrated by way of example only. In the drawings, like reference numerals depict like elements. 
   It is expressly understood, however, that the drawings are for the purpose of illustration and description only and are not intended as a definition of the limits of the invention. 
   Referring to  FIG. 1 , the underneath or lower surface section of one corner of a large area panel  10  of the present invention is shown wherein part of the panel has been cut away to show details of construction. Panel  10  has a plastic top surface  12 , a honeycomb of plastic material as an internal structure  14 , a lower plastic surface  16 , and aluminum reinforcement braces  18 . Also, panel  10  has end, locking systems  20  and side, locking systems  24 . 
   Top surface  12  is seen only through the holes  13  in internal structure  14  at the lower edge of panel  10  (as drawn), and top surface  12  and internal structure  14  are formed together as one piece as part of a plastic injection moulding operation. All plastic parts in panel  10  are formed from plastic combined with polyethylene to provide adequate strength. 
   During construction of panel  10 , all of the holes  13  of panel  10  are filled with Styrofoam™ type rigid insulating material  15 . As such, insulating material  15  is flush with the edge surface of internal structure  14 . The presence of the insulating material  15  provides an increased in the insulation R-factor of the panel  10 . Other insulating materials could be used, depending on the desired R-factor. 
   Lower surface  16  is placed over the internal structure to effectively seal panel  10 . Aluminum braces  18  are placed along the lower edges of panel  10  in order to provide additional support for the edges of panel  10 . 
   The side and end locking systems are better seen in  FIGS. 2 and 3  which show the top (or front) surface  12  of panel  10 , in  FIG. 2 , and the lower (or rear) surface  16  of panel  10 , in  FIG. 3 . 
   In  FIG. 2 , the top surface  12  of panel  10  is shown. End, locking system  20  is designed to engage corresponding end, locking system  22 .  FIG. 3  shows the lower surface  16 . 
   In  FIG. 4 , details of the locking systems  20 ,  22  and  24 ,  25  are shown wherein the grooves  42  and a projection  43  in a series of panels  100 A and  100 B are shown with a rounded “U-shaped” configuration. Other configurations are possible. 
   Panels  100 A and  100 B, which are identical in construction to each other, are shown separate from one another. Panel  100 B is also shown, in dashed lines, in alignment for locking in place with panel  100 A. To lock panels  100 A and  100 B together, panel  100 B is raised to an approximate angle of 45° to panel  100 A. The locking systems  20 ,  22  or  24 ,  25  are engaged with each other. Panel  100 B is then lowered to the surface to be protected and projection  43  will seat into groove  42 . As part of the U-shaped groove and projection, projection  42 A of panel  100 A will be inserted into “groove”  43 B of panel  100 B. 
   Once the locking mechanisms shown in  FIG. 4  are put in place, movement of the two panels in the x, y or straight up in the z axis is not possible. To disengage the panels, one edge of panel  100 B must be raised to establish the 45° angle, and locking systems  20 ,  22  or  24 ,  25  disengaged. 
     FIG. 5  shows panels  10  with locking systems  20 ,  22   a - c  and  24 ,  25   a - c  operatively engaged with each other. A staggered arrangement could be achieved by engaging  20   b  with  22   a  and  20   c  with  22   b , etc. or  24   a  with  25   b  and  24   b  with  25   c , etc. Various staggered configurations are possible depending on the number and location of the locking systems. 
   Thus, it is apparent that there has been provided, in accordance with the present invention, a protective covering system which fully satisfies the goals, objects, and advantages set forth hereinbefore. Therefore, having described specific embodiments of the present invention, it will be understood that alternatives, modifications and variations thereof may be suggested to those skilled in the art, and that it is intended that the present specification embrace all such alternatives, modifications and variations as fall within the scope of the appended claims. 
   Additionally, for clarity and unless otherwise stated, the word “comprise” and variations of the word such as “comprising” and “comprises”, when used in the description and claims of the present specification, is not intended to exclude other additives, components, integers or steps. 
   Further, while this discussion has addressed prior art known to the inventor, it is not an admission that all art discussed is citable against the present application. 
   Moreover, the words “substantially” or “essentially”, when used with an adjective or adverb is intended to enhance the scope of the particular characteristic; e.g., substantially planar is intended to mean planar, nearly planar and/or exhibiting characteristics associated with a planar element. 
   Moreover, use of the terms “he”, “him”, or “his”, is not intended to be specifically directed to persons of the masculine gender, and could easily be read as “she”, “her”, or “hers”, respectively.