Title:
DUCKBOARD FATIGUE RELIEF MAT
United States Patent 3846945
Abstract:
A duckboard mat designed to give fatigue relief when supported on an existing floor has floor engaging ribs on its underside and an upper wearing surface with openings therein. A plurality of tongues extending laterally from one side of the mat have projections thereon and a plurality of staggered tongues extending laterally from the other side have recesses therein, whereby interlocking connections may be made with like mats.
US Patent References:
/1288409.html
Hayden - December 1918 - 1288409
Mat
Hendry - April 1942 - 2279944
Plastic floor coverings
Schnee - January 1954 - 2680698
Vehicle rainshield with suction cup attaching strip
Soucy - March 1957 - 2785001
Sheet metal airfield deck mat
Areulich - March 1958 - 2826970
/1288409.html
Hayden - December 1918 - 1288409
Mat
Hendry - April 1942 - 2279944
Plastic floor coverings
Schnee - January 1954 - 2680698
Vehicle rainshield with suction cup attaching strip
Soucy - March 1957 - 2785001
Sheet metal airfield deck mat
Areulich - March 1958 - 2826970
Application Number:
05/294212
Publication Date:
11/12/1974
Filing Date:
10/02/1972
View Patent Images:
Export Citation:
Assignee:
Rubbermaid Commercial Products Inc. (Wooster, OH)
Primary Class:
Other Classes:
52/581, 404/36, 52/592.100, 404/44
International Classes:
E04F15/10; E04C1/10
Field of Search:
104/34-36,41-43 52/581,588,590,591,177,180 248/26R 15/239,240,215
US Patent References:
| 2876628 | Rapid sinking articulated revetment | March 1959 | Dixon | |
| 2999431 | Resilient mat construction | September 1961 | Mitchell | |
| 3046852 | Gratings | July 1962 | Graham | |
| 3158003 | Sectional pier | November 1964 | Dally | |
| 3438312 | GROUND COVERING CAPABLE FOR USE IN PLAYING TENNIS IN THE OPEN AIR OR UNDER COVER | April 1969 | Becker | |
| 3451169 | EDGE PROTECTOR | June 1969 | Arnold | |
| 3676971 | TILE STRUCTURE WITH CRUCIFORM SHAPED FOUNDATION SUPPORTING TILES | July 1972 | Dombroski |
Primary Examiner:
Abbott, Frank L.
Assistant Examiner:
Raduazo, Henry R.
Attorney, Agent or Firm:
Hamilton, Renner & Kenner
Claims:
I claim
1. A resilient duckboard fatigue relief mat module having a network of intersecting longitudinal and lateral major floor-engaging ribs on its underside, an upper wearing surface having openings therein, and a plurality of tongues projecting laterally from opposite sides and each having downwardly inclined top walls and floor-engaging side walls, said side walls having projections and recesses for interlocking connection with projections and recesses on the side walls of like tongues of adjoining like modules, and skid resistant strips attached to certain of said major ribs.
2. A duckboard mat as set forth in claim 1, wherein each of said skid resistant strips has a body portion and a base portion and said body portion has a longitudinally extending groove to receive said major rib.
3. A duckboard mat as set forth in claim 1, wherin said groove has barbs which frictionally engage said major rib.
1. A resilient duckboard fatigue relief mat module having a network of intersecting longitudinal and lateral major floor-engaging ribs on its underside, an upper wearing surface having openings therein, and a plurality of tongues projecting laterally from opposite sides and each having downwardly inclined top walls and floor-engaging side walls, said side walls having projections and recesses for interlocking connection with projections and recesses on the side walls of like tongues of adjoining like modules, and skid resistant strips attached to certain of said major ribs.
2. A duckboard mat as set forth in claim 1, wherein each of said skid resistant strips has a body portion and a base portion and said body portion has a longitudinally extending groove to receive said major rib.
3. A duckboard mat as set forth in claim 1, wherin said groove has barbs which frictionally engage said major rib.
Description:
BACKGROUND OF THE INVENTION
The present invention relates to duckboard fatigue relief mats. More specifically, the invention relates to a duckboard having reinforcing webs, skid resistant strips attached to the reinforcing webs and interlocking connecting members.
Duckboard flooring for restaurants, bars and other food handling places of employment requiring personnel to stand have been made of wood, rubberized materials and metal. The wood and rubberized materials have greater resiliency but absorb moisture and odors, and attempts to make the metal duckboards more resilient have resulted in complicated and costly structures.
Certain plastic floor mats have been proposed having slotted constructions but these interlock in one direction only to form strips, and in some cases require interlocking clips. Moreover, the amount of fatigue relief afforded by these mats is dependent upon the inherent resiliency of the plastic materials, and the slotted construction provides a supporting surface which becomes uncomfortable during extended periods of use.
Another prior mat utilizes a first set of parallel elongated rectangular rubber strips which have a plurality of longitudinal spaced-apart apertures as well as pairs of notches on opposed strip surfaces, with the notches disposed between the apertures. A second set of similar strips exists in transverse alignment with the first strips and matingly engages the first strips with the notches of the second strips residing in the apertures of the first strips. Such a construction, however, is costly as well as unyielding or rigid, and thus is also uncomfortable during extended periods of use.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provde a duckboard fatigue relief mat which has openings in the wear surface.
It is another object of the present invention to provide a duckboard mat, as above, in which tongue portions interlock with the tongue portions of other duckboard modules.
It is a further object of the present invention to provide a duckboard mat, as above, which is skid resistant.
It is yet another object of the present invention to provide a duckboard mat, as above, which is resilient and shock absorbent.
It is yet a further object of the present invention to provide a duckboard mat, as above, which has reinforced webbing.
It is still another object of the present invention to provide a duckboard mat, as above, which is designed to permit good circulation of air to abate mold, mildew and odors.
These and other objects of the present invention, together with the advantages thereof over existing and prior art forms, are accomplished by the improvements hereinafter described and claimed.
In general, the improved duckboard mat is made of a resilient material and has a plurality of tongues extending therefrom. The tongues have projecting members and receiving members which engage receiving and projecting members on adjoining like modules, thereby interlocking the modules to each other.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of a duckboard mat interlocked with other mats.
FIG. 2 is a bottom plan view of a single duckboard mat showing reinforcing webbing and skid resistant strips.
FIG. 3 is a side elevation taken on line 3--3 of FIG. 1.
FIG. 4 is an end elevation taken on line 4--4 of FIG. 1.
FIG. 5 is a sectional view taken on line 5--5 of FIG. 1 showing the end connection between two adjoining duckboard mats.
FIG. 6 is a sectional view taken on line 6--6 of FIG. 1 showing the tongue connection members between two side-adjoining mats.
FIG. 7 is a sectional view taken on line 7--7 of FIG. 5 showing the shape of an end projection interlocked in an aperture.
FIG. 8 is a sectional view taken on line 8--8 of FIG. 2 showing a skid resistant strip attached to a major reinforcing web.
FIG. 9 is a sectional view taken on line 9--9 of FIG. 8 showing the engagement between the strip and the web.
FIG. 10 is a sectional view taken on line 10--10 of FIG. 8 similar to FIG. 9 but showing a recess in the major web.
FIG. 11 is a perspective view of the skid resistant strip.
FIG. 12 is a top plan view of a duckboard border.
FIG. 13 is a side elevation of a duckboard border taken on line 13--13 of FIG. 12.
FIG. 14 is a partial top plan view of a corner portion of a duckboard mat interlocked with a border.
FIG. 15 is a sectional view taken on line 15--15 of FIG. 14 showing one manner of interlocking the border and the duckboard.
FIG. 16 is a sectional view taken on line 16--16 of FIG. 14 showing another manner of interlocking the border and the duckboard.
FIG. 17 is a sectional view taken on line 17--17 of FIG. 2 showing a portion of the reinforcing webbing.
FIG. 18 is a sectional view taken on line 18--18 of FIG. 2 showing yet another portion of the reinforcing webbing.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In general, a duckboard fatigue relief mat according to the concept of the present invention is generally indicated by the numeral 10. As shown in FIG. 1, the top or wear surface of the duckboard, generally indicated by the numeral 11, has openings 12 and grip ridges 13. Preferably, the top surface is arranged in a checkerboard pattern with alternate squares having openings 12 and ridges 13 in the longitudinal and lateral or transverse directions. The openings 12, which may comprise two rectangular apertures per square with a separating rib 14, may furthermore alternate in alignment by being longitudinally aligned in one longitudinal row 12A and by being transversely aligned in adjacent longitudinal rows 12B. Similarly, the ridges may have alternating longitudinal rows of longitudinally and transversely aligned ridges, as shown in FIG. 1. Of course, other layouts as well as other patterns may be used to form any of a large number of designs so long as sufficient ridges exist in an area to provide gripping surfaces and, generally, sufficient openings exist to permit air circulation which abates mold and mildew. The duckboard preferably is made by injection molding and preferred plastics are polyvinyl chloride and polyethylene.
Each side of duckboard 10 contains a plurality of tongues 15 which extend laterally outwardly. As best seen in FIG. 2, the tongues may be aligned with every other square on one side of the duckboard and, on the opposite side, aligned with alternating squares which are located between the tongues of the initial side. Such an arrangement of tongues, of course, permits a particular duckboard module to engage or mesh with adjacent modules. As seen in FIG. 4, the top walls of the tongues have inclined outer portions 16 to permit a smooth transition from top surface 11 to a floor and similarly the side portions of the duckboard between the tongues have inclined portions 16'.
Adjacent modules are secured to one another by interlocking tongue connectors, generally indicated by the numeral 17. In the preferred embodiment shown, the tongue connectors comprise projecting members 18 on various tongues preferably located on one side of the module and receiving members 19 located preferably in all of the tongues on the other side. The projections 18 preferably are laterally extending studs in the tongue side walls which may be U-shaped (FIG. 7) and engage the receiving members 19 in another module which may be in the shape of keyhole apertures in the tongue side walls (FIG. 4). Such projections and apertures are arranged so that they matingly engage the apertures and projections of an adjacent side module as shown in FIG. 6.
In order to secure the ends of adjacent duckboard modules to each other, an end connector member, generally indicated by the numeral 21, is utilized. The end connector may be similar to the tongue connector in that it may comprise a U-shaped projection 22 having a flange 23 and a keyhole-shaped aperture 24, both of which are located in end wall 25 and matingly engage, respectively, a keyhole-shaped aperture and a projection located in the end wall of an adjacent module. Preferably, each duckboard module has at least two end connectors so positioned that they may matingly engage adjacent end modules and securely interlock the modules to each other.
Referring now to FIGS. 12 through 16, if a particular duckboard end wall 25 is not connected to another duckboard module, it preferably is connected to a border member, generally indicated by the numeral 31. Preferably, the border has an inclined surface 32 which merges into a top surface 33 at a height substantially equal to the duckboard surface 11 so that a smooth transition is made from a floor to a duckboard end portion. Since the duckboard tongues are inclined at their outermost sides, a border is not needed in this area. Hence, carts, dollies and other equipment can better be rolled onto and off the duckboard ends or sides. In the particular duckboard embodiment shown in FIG. 2, each end has an extending tongue on one side, whereas the tongue on the opposite side is staggered or longitudinally offset. Therefore, border member 31 may be L-shaped as shown in FIG. 12. Since duckboard end wall 25 already has a projection 22 and an aperture 24, borders 31 may conveniently be provided with a matingly engageable, similarly aligned projection 34 and keyhole aperture 35. Thus, as seen in FIG. 15, border projection 34 extends through end wall aperture 35 with projection flange 36 engaging end wall 25 to maintain a secure and rigid alignment. Similarly, as seen in FIG. 16, projection 22 engages border aperture 35 and end projection flange 23 engages border leg wall 37 to effect a snug interlock.
The entire duckboard 10 is supported by a plurality of longitudinally aligned transverse skid resistant strips, generally indicated by the numeral 41, which are preferably located in the central portion of the duckboard, FIG. 2. Strips 41 have a body portion 42 and a base portion 43. The body portion has a downwardly extending groove 44 which preferably engages a major transverse web. Downwardly directed barbs 45 extend into the groove and are compressed when the transverse web loads the strip causing the barbs to frictionally engage the duckboard web. The base portion of the strips extends laterally of body portion 42 to provide stability and has a plurality of bottom ridges 46 which provide gripping surfaces to prevent duckboard movement. Since the body portion and the base portion perform different functions, they are preferably made out of different materials. The body portion of the strip which supports the weight of the duckboard, as well as persons and articles, is generally made of semirigid plastic such as a high density polyethylene, whereas the base portion which grips various surfaces is generally made of a flexible plastic such as a resilient low density polyethylene.
Considering now duckboard 10, it has a network of major reinforcing webs which extend downwardly from top surface 11 and engage a floor or other substrate. Generally, the major webs are located in the vicinity of the surface openings and since a large number of top surface layouts may exist, the number of possible layouts of the major webs are also large. In the embodiment shown in FIG. 2, a plurality of major longitudinal webs 51 extend between end walls 25 and a plurality of major transverse webs 61 extend the width of the duckboard. Preferably, the longitudinal webs extend or run between the longitudinally orientated apertures 12A and the transverse webs extend or run between the transversely orientated apertures 12B, and thus provide a reinforcement for separating rib 14. Additionally, as shown in FIG. 2, tongue 15, including inclined tongue portions 16 as well as inclined side portions 16' of the duckboard are provided with longitudinally reinforcing ribs 52 and also transversely reinforcing ribs 62 which extend to the same depth as the major webs.
Although the major longitudinal and transverse webs provide adequate reinforcement for most uses, they do not provide sufficient support for localized stresses or weight concentrations such as the heel of a shoe or the wheel of a cart in portions of the duckboard located between the major webs. It is, therefore, desirable to have secondary reinforcing ribs to provide adequate support through the duckboard module. As with the major webs, any of a large number of layouts may be utilized. In the present embodiment, a longitudinal secondary web 55 is located laterally of or on both sides of the longitudinally orientated apertures 12A and extends the full length of the duckboard module. Likewise, secondary transverse webs 65 are located laterally of or on both sides of the transversely orientated apertures 12B and, as shown in FIG. 2, extend between the outermost major longitudinal webs 51.
In order to permit skid resistant strips 41 to be attached to the major transverse webs, a central recess 71 exists in the medial or central major longitudinal web at its intersection with each major transverse web and at the end walls 25. Since base portion 43 of strips 41 lies beneath major transverse web 61, thereby elevating the bottom of the center portion of the duckboard module above a floor, water and other fluids are free to flow through the central vicinity of the duckboard. Side recesses 72 are provided at the intersections of major transverse webs 61 and the outermost longitudinal webs 51 to enable positioning of additional strips at the sides if desired. Side recesses 72 may generally be of any shape as long as they provide adequate passage. For example, FIG. 17 discloses a rectangular recess in the longitudinal web 51 and the recess in transverse web 61 is similarly shaped, although it is not shown. In FIG. 18, the longitudinal recess is U-shaped, whereas the transverse recess (not shown) is rectangularly shaped as are the recesses shown in FIG. 17. Furthermore, a tongue recess 73 may be located at various intersections with longitudinal ribs 52 and transverse ribs 62.
A duckboard reinforced as shown in FIG. 2 has been found to support heavy localized load concentrations and yet give fatigue relief to a person's feet. Additionally, the various recesses in the major webs and the ribs along with the elevated central portion permit fluid to flow through the duckboard in any direction. Surface openings 12 permit water and other fluids to drain through the duckboard surface and allow air to circulate beneath the duckboard through the recesses, thereby preventing mold and mildew buildup. Because of the inclined tongues and inclined borders, no abrupt changes exist from a floor to duckboard surface 11. Since the modules interlock at the tongue portions as well as at the end portions, a multitude of various floor layouts can be prepared.
It should thus be evident that a duckboard fatigue relief mat constructed according to the concepts of the present invention has been shown and described in sufficient detail to enable one skilled in the art to practice the invention. Since various modifications in the construction, interlocking and reinforcement of the duckboard are within the spirit of the invention herein disclosed and described, the scope of the invention is limited solely by the scope of the claims.
The present invention relates to duckboard fatigue relief mats. More specifically, the invention relates to a duckboard having reinforcing webs, skid resistant strips attached to the reinforcing webs and interlocking connecting members.
Duckboard flooring for restaurants, bars and other food handling places of employment requiring personnel to stand have been made of wood, rubberized materials and metal. The wood and rubberized materials have greater resiliency but absorb moisture and odors, and attempts to make the metal duckboards more resilient have resulted in complicated and costly structures.
Certain plastic floor mats have been proposed having slotted constructions but these interlock in one direction only to form strips, and in some cases require interlocking clips. Moreover, the amount of fatigue relief afforded by these mats is dependent upon the inherent resiliency of the plastic materials, and the slotted construction provides a supporting surface which becomes uncomfortable during extended periods of use.
Another prior mat utilizes a first set of parallel elongated rectangular rubber strips which have a plurality of longitudinal spaced-apart apertures as well as pairs of notches on opposed strip surfaces, with the notches disposed between the apertures. A second set of similar strips exists in transverse alignment with the first strips and matingly engages the first strips with the notches of the second strips residing in the apertures of the first strips. Such a construction, however, is costly as well as unyielding or rigid, and thus is also uncomfortable during extended periods of use.
SUMMARY OF THE INVENTION
It is, therefore, an object of the present invention to provde a duckboard fatigue relief mat which has openings in the wear surface.
It is another object of the present invention to provide a duckboard mat, as above, in which tongue portions interlock with the tongue portions of other duckboard modules.
It is a further object of the present invention to provide a duckboard mat, as above, which is skid resistant.
It is yet another object of the present invention to provide a duckboard mat, as above, which is resilient and shock absorbent.
It is yet a further object of the present invention to provide a duckboard mat, as above, which has reinforced webbing.
It is still another object of the present invention to provide a duckboard mat, as above, which is designed to permit good circulation of air to abate mold, mildew and odors.
These and other objects of the present invention, together with the advantages thereof over existing and prior art forms, are accomplished by the improvements hereinafter described and claimed.
In general, the improved duckboard mat is made of a resilient material and has a plurality of tongues extending therefrom. The tongues have projecting members and receiving members which engage receiving and projecting members on adjoining like modules, thereby interlocking the modules to each other.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of a duckboard mat interlocked with other mats.
FIG. 2 is a bottom plan view of a single duckboard mat showing reinforcing webbing and skid resistant strips.
FIG. 3 is a side elevation taken on line 3--3 of FIG. 1.
FIG. 4 is an end elevation taken on line 4--4 of FIG. 1.
FIG. 5 is a sectional view taken on line 5--5 of FIG. 1 showing the end connection between two adjoining duckboard mats.
FIG. 6 is a sectional view taken on line 6--6 of FIG. 1 showing the tongue connection members between two side-adjoining mats.
FIG. 7 is a sectional view taken on line 7--7 of FIG. 5 showing the shape of an end projection interlocked in an aperture.
FIG. 8 is a sectional view taken on line 8--8 of FIG. 2 showing a skid resistant strip attached to a major reinforcing web.
FIG. 9 is a sectional view taken on line 9--9 of FIG. 8 showing the engagement between the strip and the web.
FIG. 10 is a sectional view taken on line 10--10 of FIG. 8 similar to FIG. 9 but showing a recess in the major web.
FIG. 11 is a perspective view of the skid resistant strip.
FIG. 12 is a top plan view of a duckboard border.
FIG. 13 is a side elevation of a duckboard border taken on line 13--13 of FIG. 12.
FIG. 14 is a partial top plan view of a corner portion of a duckboard mat interlocked with a border.
FIG. 15 is a sectional view taken on line 15--15 of FIG. 14 showing one manner of interlocking the border and the duckboard.
FIG. 16 is a sectional view taken on line 16--16 of FIG. 14 showing another manner of interlocking the border and the duckboard.
FIG. 17 is a sectional view taken on line 17--17 of FIG. 2 showing a portion of the reinforcing webbing.
FIG. 18 is a sectional view taken on line 18--18 of FIG. 2 showing yet another portion of the reinforcing webbing.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In general, a duckboard fatigue relief mat according to the concept of the present invention is generally indicated by the numeral 10. As shown in FIG. 1, the top or wear surface of the duckboard, generally indicated by the numeral 11, has openings 12 and grip ridges 13. Preferably, the top surface is arranged in a checkerboard pattern with alternate squares having openings 12 and ridges 13 in the longitudinal and lateral or transverse directions. The openings 12, which may comprise two rectangular apertures per square with a separating rib 14, may furthermore alternate in alignment by being longitudinally aligned in one longitudinal row 12A and by being transversely aligned in adjacent longitudinal rows 12B. Similarly, the ridges may have alternating longitudinal rows of longitudinally and transversely aligned ridges, as shown in FIG. 1. Of course, other layouts as well as other patterns may be used to form any of a large number of designs so long as sufficient ridges exist in an area to provide gripping surfaces and, generally, sufficient openings exist to permit air circulation which abates mold and mildew. The duckboard preferably is made by injection molding and preferred plastics are polyvinyl chloride and polyethylene.
Each side of duckboard 10 contains a plurality of tongues 15 which extend laterally outwardly. As best seen in FIG. 2, the tongues may be aligned with every other square on one side of the duckboard and, on the opposite side, aligned with alternating squares which are located between the tongues of the initial side. Such an arrangement of tongues, of course, permits a particular duckboard module to engage or mesh with adjacent modules. As seen in FIG. 4, the top walls of the tongues have inclined outer portions 16 to permit a smooth transition from top surface 11 to a floor and similarly the side portions of the duckboard between the tongues have inclined portions 16'.
Adjacent modules are secured to one another by interlocking tongue connectors, generally indicated by the numeral 17. In the preferred embodiment shown, the tongue connectors comprise projecting members 18 on various tongues preferably located on one side of the module and receiving members 19 located preferably in all of the tongues on the other side. The projections 18 preferably are laterally extending studs in the tongue side walls which may be U-shaped (FIG. 7) and engage the receiving members 19 in another module which may be in the shape of keyhole apertures in the tongue side walls (FIG. 4). Such projections and apertures are arranged so that they matingly engage the apertures and projections of an adjacent side module as shown in FIG. 6.
In order to secure the ends of adjacent duckboard modules to each other, an end connector member, generally indicated by the numeral 21, is utilized. The end connector may be similar to the tongue connector in that it may comprise a U-shaped projection 22 having a flange 23 and a keyhole-shaped aperture 24, both of which are located in end wall 25 and matingly engage, respectively, a keyhole-shaped aperture and a projection located in the end wall of an adjacent module. Preferably, each duckboard module has at least two end connectors so positioned that they may matingly engage adjacent end modules and securely interlock the modules to each other.
Referring now to FIGS. 12 through 16, if a particular duckboard end wall 25 is not connected to another duckboard module, it preferably is connected to a border member, generally indicated by the numeral 31. Preferably, the border has an inclined surface 32 which merges into a top surface 33 at a height substantially equal to the duckboard surface 11 so that a smooth transition is made from a floor to a duckboard end portion. Since the duckboard tongues are inclined at their outermost sides, a border is not needed in this area. Hence, carts, dollies and other equipment can better be rolled onto and off the duckboard ends or sides. In the particular duckboard embodiment shown in FIG. 2, each end has an extending tongue on one side, whereas the tongue on the opposite side is staggered or longitudinally offset. Therefore, border member 31 may be L-shaped as shown in FIG. 12. Since duckboard end wall 25 already has a projection 22 and an aperture 24, borders 31 may conveniently be provided with a matingly engageable, similarly aligned projection 34 and keyhole aperture 35. Thus, as seen in FIG. 15, border projection 34 extends through end wall aperture 35 with projection flange 36 engaging end wall 25 to maintain a secure and rigid alignment. Similarly, as seen in FIG. 16, projection 22 engages border aperture 35 and end projection flange 23 engages border leg wall 37 to effect a snug interlock.
The entire duckboard 10 is supported by a plurality of longitudinally aligned transverse skid resistant strips, generally indicated by the numeral 41, which are preferably located in the central portion of the duckboard, FIG. 2. Strips 41 have a body portion 42 and a base portion 43. The body portion has a downwardly extending groove 44 which preferably engages a major transverse web. Downwardly directed barbs 45 extend into the groove and are compressed when the transverse web loads the strip causing the barbs to frictionally engage the duckboard web. The base portion of the strips extends laterally of body portion 42 to provide stability and has a plurality of bottom ridges 46 which provide gripping surfaces to prevent duckboard movement. Since the body portion and the base portion perform different functions, they are preferably made out of different materials. The body portion of the strip which supports the weight of the duckboard, as well as persons and articles, is generally made of semirigid plastic such as a high density polyethylene, whereas the base portion which grips various surfaces is generally made of a flexible plastic such as a resilient low density polyethylene.
Considering now duckboard 10, it has a network of major reinforcing webs which extend downwardly from top surface 11 and engage a floor or other substrate. Generally, the major webs are located in the vicinity of the surface openings and since a large number of top surface layouts may exist, the number of possible layouts of the major webs are also large. In the embodiment shown in FIG. 2, a plurality of major longitudinal webs 51 extend between end walls 25 and a plurality of major transverse webs 61 extend the width of the duckboard. Preferably, the longitudinal webs extend or run between the longitudinally orientated apertures 12A and the transverse webs extend or run between the transversely orientated apertures 12B, and thus provide a reinforcement for separating rib 14. Additionally, as shown in FIG. 2, tongue 15, including inclined tongue portions 16 as well as inclined side portions 16' of the duckboard are provided with longitudinally reinforcing ribs 52 and also transversely reinforcing ribs 62 which extend to the same depth as the major webs.
Although the major longitudinal and transverse webs provide adequate reinforcement for most uses, they do not provide sufficient support for localized stresses or weight concentrations such as the heel of a shoe or the wheel of a cart in portions of the duckboard located between the major webs. It is, therefore, desirable to have secondary reinforcing ribs to provide adequate support through the duckboard module. As with the major webs, any of a large number of layouts may be utilized. In the present embodiment, a longitudinal secondary web 55 is located laterally of or on both sides of the longitudinally orientated apertures 12A and extends the full length of the duckboard module. Likewise, secondary transverse webs 65 are located laterally of or on both sides of the transversely orientated apertures 12B and, as shown in FIG. 2, extend between the outermost major longitudinal webs 51.
In order to permit skid resistant strips 41 to be attached to the major transverse webs, a central recess 71 exists in the medial or central major longitudinal web at its intersection with each major transverse web and at the end walls 25. Since base portion 43 of strips 41 lies beneath major transverse web 61, thereby elevating the bottom of the center portion of the duckboard module above a floor, water and other fluids are free to flow through the central vicinity of the duckboard. Side recesses 72 are provided at the intersections of major transverse webs 61 and the outermost longitudinal webs 51 to enable positioning of additional strips at the sides if desired. Side recesses 72 may generally be of any shape as long as they provide adequate passage. For example, FIG. 17 discloses a rectangular recess in the longitudinal web 51 and the recess in transverse web 61 is similarly shaped, although it is not shown. In FIG. 18, the longitudinal recess is U-shaped, whereas the transverse recess (not shown) is rectangularly shaped as are the recesses shown in FIG. 17. Furthermore, a tongue recess 73 may be located at various intersections with longitudinal ribs 52 and transverse ribs 62.
A duckboard reinforced as shown in FIG. 2 has been found to support heavy localized load concentrations and yet give fatigue relief to a person's feet. Additionally, the various recesses in the major webs and the ribs along with the elevated central portion permit fluid to flow through the duckboard in any direction. Surface openings 12 permit water and other fluids to drain through the duckboard surface and allow air to circulate beneath the duckboard through the recesses, thereby preventing mold and mildew buildup. Because of the inclined tongues and inclined borders, no abrupt changes exist from a floor to duckboard surface 11. Since the modules interlock at the tongue portions as well as at the end portions, a multitude of various floor layouts can be prepared.
It should thus be evident that a duckboard fatigue relief mat constructed according to the concepts of the present invention has been shown and described in sufficient detail to enable one skilled in the art to practice the invention. Since various modifications in the construction, interlocking and reinforcement of the duckboard are within the spirit of the invention herein disclosed and described, the scope of the invention is limited solely by the scope of the claims.