GB2451867A

GB2451867A - Non-slip open flooring

Info

Publication number: GB2451867A
Application number: GB0715902A
Authority: GB
Inventors: Alan Williamson
Original assignee: Redman Fisher Engineering Ltd
Current assignee: Redman Fisher Engineering Ltd
Priority date: 2007-08-15
Filing date: 2007-08-15
Publication date: 2009-02-18
Anticipated expiration: 2027-08-15
Also published as: GB2451867B; WO2009022160A1; GB0715902D0

Abstract

Flooring (10) comprising a plurality of elongate load bearing elements (12) joined by a plurality of transverse connecting elements (14), the load bearing elements having an uppermost surface (12a) provided with a tread comprising a plurality of topographical formations. These may be a series of parallel ridges extending perpendicular to the longitudinal axis of the load bearing element. These ridges may be a plurality of peaks and may be distributed evenly over the uppermost surface of the load bearing element. Alternatively, they may be arranged in clusters which may be separated by a groove. The tread has a height of between 600 - 1000 microns and preferably has a spacing between the peaks of between 500 - 3000 microns. Preferably the flooring may be metal with cylindrical rods as the connecting elements. The invention also relates to a method of manufacturing the flooring which may include forming the ridges through knurling. In use, the invention provides an anti-slip flooring for users of both traditional cleated sole and new style smooth soled safety footwear without causing damage to soles.

Description

Title: Flooring DescriDtion of Invention The present invention relates to flooring, particularly open metallic flooring for use in industrial, construction, commercial, retail and architectural applications.

Where non-slip flooring is required for industrial, construction, commercial, retail and architectural sites, it is known to use open flooring comprising a grid of metal bars. Such flooring typically includes a plurality of load bearing bars joined by a plurality of transverse bars. The load bearing bars are made from rolled or slit metal strips and each is arranged with its major surfaces extending perpendicular to the plane of the floor so that one of its longitudinal edges, hereinafter referred to as the bearing edge, provides a bearing surface on which a user walks.

In order to provide the flooring with the required degree of slip resistance to comply with British Standard 4592:PtO-2006, for example, it is known to provide the bearing edge with a tread in the form of a plurality of serrations with a peak to valley height of the order of 3mm. The serrations are of such as * *.

*... 20 size that they can lock into a typical tread used in industrial safety footwear, and thus provide the desired high static coefficient of friction between shoe and the flooring.

** S...

* S Traditionally virtually all industrial and safety footwear had cleated soles, but developments in footwear to achieve better anti-slip properties has resulted in a myriad of new types of industrial or safety footwear many of which do not have cleated soles. Testing of industrial flooring to establish whether it has the required degree of slip resistance to comply with BS4592:PtO-2006 is therefore carried out using smooth soled footwear. Thus, to achieve the required degree of slip resistance to meet the relevant standards, further increase in friction is required, and this has been achieved by increasing the sharpness of the peak of each serration. This can result in damage to the sole of a shoe in contact with the floor, thus increasing wear of footwear, and even increase the risk of injury through lacerations on falling. Moreover, when such flooring is used by a wearer of footwear with cleated soles, the friction between the footwear and the flooring can be so high that walking on the flooring causes the user excessive fatigue.

According to a first aspect of the invention we provide a flooring comprising a plurality of elongate load bearing elements joined by a plurality of transverse connecting elements the load bearing elements having an uppermost surface, the uppermost surface being provided with a tread comprising a plurality of topographical formations, the height of which is between 600pm and 1000pm.

The topographical formations are preferably a series of generally parallel ridges, in which case, the ridges preferably extend generally perpendicular to the longitudinal axis of the load bearing element. The topographical formations may alternatively be a plurality of peaks.

The topographical formations may be distributed generally evenly over substantially the entire extent of the uppermost surface of the load bearing elements, or may be arranged in clusters over a proportion of the surface area of the uppermost surface. In the latter case, adjacent clusters of topographical formations may be separated by a groove having a depth which is significantly *.....

* : greater than the height of the topographical formations.

*.S*.* * * The separation of the highest points of adjacent topographical formations is : preferably between 500pm and 3000pm.

*****. * *

The material ratio of the bearing surface is between 5/25mm and 11/25mm measured to 600pm depth.

Advantageously, the load bearing elements are made from metal strips and each is arranged with its major surfaces extending perpendicular to the plane of the floor so that one of its longitudinal edges forms the uppermost surface.

The connecting elements may be generally cylindrical rods, or may be formed from a twisted square cross-section rod.

According to a second aspect of the invention we provide a method of making a load bearing element for a flooring comprising a plurality of elongate load bearing elements joined by a plurality of transverse connecting elements, the load bearing elements having an uppermost surface, the method including forming in the uppermost surface a plurality of topographical formations, the height of which is between 600pm and 1000pm.

Preferably the load bearing element is metallic, and the method includes the steps of rolling the load bearing element into an elongate strip, and forming the topographical formations on one of the longitudinal minor surfaces of the strip.

Advantageously the topographical formations comprise a plurality of ridges and the method includes the step of forming the ridges by rolling of a knurled roller along the bearing edge of the load bearing element.

Embodiments of the invention will now be described with reference to the * ** following drawings of which: * *.

FIGURE 1 is an illustration of a section of flooring according to the first aspect of the invention; II.... *

20 FIGURE 2 is an illustration of detail of a load bearing bar of the flooring shown in Figure 1, FIGURE 3 is an illustration of an alternative configuration of load bearing bar to that shown in Figure 2, and FIGURE 4 is an illustration of the profile of the topographical formations applied to the bearing edge of the load bearing bars shown in Figures 2 and 3.

Referring now to Figure 1, there is shown a section of flooring 10 comprising a grid formed from a plurality of parallel load bearing bars 12, and a plurality of transverse bars 14 joining the load bearing bars 12. The load bearing bars 12 are formed from strips of a metallic material and are each arranged with its major surfaces extending generally perpendicular to the plane of the floor, so that one of the longitudinal edges of each bar 12 provides a surface on which a user may walk, hereinafter referred to as the bearing edge 12a.

In this example, each transverse bar 14 is formed from a rod with a generally circular transverse cross-section, and extends with its longitudinal axis generally perpendicular to the longitudinal axes of the load bearing bars 12.

The transverse bars 14 are mounted in a plurality of appropriately spaced slots in the bars 12 and welded to the load bearing bars 12 in a manner which is conventional in the production of such flooring. The transverse bars 14 may alternatively be made from a twisted rod with a generally square cross-section, and may be secured to the load bearing bars 12 by placing the transverse bars 14 on the bearing surfaces 12a of the load bearing bars 12 and forge welding the transverse bars 14 in place.

* Referring now to Figure 2, in which the bearing edge 12a of load bearing bar 12 is shown in more detail, the bearing edge 12a is, on a macroscopic scale, ***. * *

generally flat, but is provided with a tread in the form of a plurality of ridges which extend generally perpendicular to the longitudinal axis of the bearing edge 12a. In this example, the ridges are around 800pm in height (Rz as defined in BS1 134), with a mean peak-to-peak spacing (S as defined in BS1134) of around 2000pm. To avoid excessive wear of a user's footwear, the ridges are shaped such that the material ratio is of the order of llmm/25mm at a depth of 600pm. The material ratio (Mr as defined in BS1134) is defined as the length of flooring in contact with a flat sole penetrated by the peaks to a depth of 600pm over a specified length of flooring i.e. (xi + x2 +x3 + x + x5/pm), as illustrated in Figure 4.

It should be appreciated that, to achieve the desired slip-resistance, the surface roughness profile need not be exactly as illustrated in Figure 4 -the mean ridge height may be between 600pm and 1000pm, and the mean peak-to-peak spacing may be between l500pm and 3000pm, or may even be as low as 500pm.

The surface roughness profile may comprise a plurality of conical, pyramidal, or approximately conical or pyramidal peaks rather than ridges, and or could be applied to a bearing edge 12a which is not generally flat on a macroscopic scale, as illustrated in Figure 3. In this embodiment of the invention, the bearing edge I 2a is provided with a plurality of macroscopic serrations, of comparable size to the serrations used in prior art flooring, i.e. around 3mm in height, and around 20mm peak-to-peak spacing. The top portion, around 10mm in length, of each serration is provided with the surface roughness profile similar to that described above, i.e. with a plurality of ridges having a height of around 800pm and a peak-to-peak separation of around 2000pm. In other words, the ridges are provided in clusters of around five ridges, adjacent clusters being separated by a groove of around 3mm in depth. The material ratio Mr of this embodiment of the invention is around 5mm/25mm at 600pm **1*** depth. * ** **** * *

Unlike in the prior art flooring, flooring according to the invention does not rely on the cleated soles of industrial flooring locking into serrations on the bearing edges of the flooring to achieve the desired slip-resistance. The ridges of the surface roughness profile applied to flooring according to the invention are too small and closely spaced for this to occur. Instead, the desired slip resistance is achieved by virtue of elastic deformation of the sole of a user's footwear around the ridges. Use of a surface roughness profile having the parameters set out above has been found to produce a flooring with the desired slip resistance which does not cause significant damage to a user's footwear.

Moreover, by appropriate combination of R, S, Mr and footwear excessive user fatigue may be reduced or avoided.

The load bearing bars 12 are preferably fabricated by hot rolling, and if this is the case, the surface roughness profile described above is provided by applying a knurled roller, with a surface profile which is generally the inverse of the desired surface roughness profile, to the bearing edge of each bar as a continuous part of the hot rolling process, during the later stages of the process. The surface profile of the knurled roller may vary slightly from the precise inverse of the desired surface profile, to allow for the fact that the bar material may not completely fill the valleys in the surface profile of the knurled roller during rolling if application of the pressure required to achieve complete matching of the profiles would cause unwanted macroscopic deformation of the bar.

The hot rolling process is substantially the same as the process of hot rolling the load bearing bars for conventional metallic flooring, except that at stand 8 of the rolling process, the side of the bar adjacent the bearing edge are tapered inwards to produce a truncated triangular portion in transverse cross-section. This is done to provide space for excess material to flow into during subsequent rolling operation without any unwanted bulges being formed in the cross-section of the bar. At stand 9 of the rolling process, the thickness of the bar is reduced, the surface roughness profile is applied at stand 10, and the * *.

***..* 20 thickness of the bar is reduced to its final value at stand 11. *S..

The bars may alternatively be produced by taking a rolled plate of the desired thickness, and cutting it into a plurality of strips of the desired depth. In this case, the surface roughness profile is applied in a separate cold rolling process after the slitting operation. * * *

A final alternative fabrication method is to cast the bars, in which case the surface roughness profile is incorporated into the mold shape.

The load bearing bars 12 may be galvanised once formed to the desired shape.

When used in this specification and claims, the terms "comprises" and "comprising" and variations thereof mean that the specified features, steps or integers are included. The terms are not to be interpreted to exclude the presence of other features, steps or components.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof. * S. * * . * S S. * . S.'.

*55... * S

S

*S*... * * *S * * * S..

S

*SSS.. * .

Claims

Claims 1. Flooring comprising a plurality of elongate load bearing elements joined by a plurality of transverse connecting elements the load bearing elements having an uppermost surface, the uppermost surface being provided with a tread comprising a plurality of topographical formations, the height of which is between 600pm and 1000pm.
2. Flooring according to claim I wherein the topographical formations are a series of generally parallel ridges.
3. Flooring according to claim 2 wherein the ridges extend generally perpendicular to the longitudinal axis of the load bearing element.
4. Flooring according to claim 1 wherein the topographical formations are a plurality of peaks.
5. Flooring according to any preceding claim wherein the topographical formations are distributed generally evenly over substantially the entire extent of the uppermost surface of the load bearing elements. * **
6. Flooring according to any one of claims I to 4 wherein the ***. * *

topographical formations are arranged in clusters over a proportion of the surface area of the uppermost surface.
7. Flooring according to claim 6 wherein adjacent clusters of topographical :. 20 formations are separated by a groove having a depth which is significantly *..**: greater than the height of the topographical formations.
8. Flooring according to any preceding claim wherein the separation of the highest points of adjacent topographical formations is preferably between 500pm and 3000pm.
9. Flooring according to any preceding claim wherein the load bearing elements are made from metal strips and each is arranged with its major surfaces extending perpendicular to the plane of the floor so that one of its longitudinal edges forms the uppermost surface.
10. Flooring according to any preceding claim wherein the connecting elements are generally cylindrical rods.
11. A method of making a load bearing element for a flooring comprising a plurality of elongate load bearing elements joined by a plurality of transverse connecting elements, the load bearing elements having an uppermost surface, the method including the forming in the uppermost surface a plurality of topographical formations, the height of which is between 600pm and 1000pm.
12. A method according to claim 11 wherein the load bearing element is metallic, and the method includes the steps of rolling the load bearing element into an elongate strip, and forming the topographical formations on one of the longitudinal minor surfaces of the strip.
13. A method according to claim 11 or 12 wherein the topographical * .. formations comprise a plurality of ridges and the method includes the step of forming the ridges by rolling of a knurled roller along the bearing edge of the load bearing element.

S.....

* 20
14. A flooring substantially as hereinbefore described with reference to and *....

* as shown in the accompanying drawings. *.
15. A method of making a flooring substantially as hereinbefore described ****..

* with reference to the accompanying drawings.
16. Any novel feature or novel combination of features described herein and/or in the accompanying drawings.