GB1593869A

GB1593869A - Open flooring

Info

Publication number: GB1593869A
Application number: GB50250/77A
Authority: GB
Original assignee: Redman Fisher Engineering Ltd
Current assignee: Redman Fisher Engineering Ltd
Priority date: 1977-12-02
Filing date: 1977-12-02
Publication date: 1981-07-22
Also published as: FR2410712A1; WO1978000002A2; WO1978000002A3; FR2410712B1; GB2036149A; GB2036149B; NO783308L

Abstract

The invention relates to open flooring comprising a plurality of longitudinal bars (10) connected together by transverse bars (11) each of which extends across a number of the longitudinal bars. In the gaps between adjacent longitudinal bars there are provided rectilinear intermediate elements (12) which have a smaller cross section than do the longitudinal bars. The upper edges of the transverse bars lie in the same plane as the upper-edges of the longitudinal bars. The intermediate elements are secured beneath the transverse bars. In manufacture of the flooring the longitudinal bars and intermediate elements are supported in the required relative positions and the transverse bars are then secured by forge welding.

Description

(54) IMPROVEMENTS RELATING TO OPEN FLOORING (71) We, REDMAN FISHER ENGINEER ING LIMITED, a British Company, of P. O.

Box. 12, Birmingham New Road, Tipton, West Midlands, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to open flooring comprising a plurality of longitudinal bars which are parallel to each other and are connected together by transverse bars.

There are two kinds of open flooring in common use. The first kind is frequently referred to as diamond pattern flooring and in this kind there lies between each pair of adjacent longitudinal bars a bar which is non-rectilinear and is attached to the longitudinal bars alternatively at successive positions along its length. The second kind is referred to hereinafter as flooring of the kind specified. In flooring of the kind specified the longitudinal bars are connected together by transverse bars each of which extends across more than two longitudinal bars. Usually, in flooring of the kind specified, each transverse bar is rectilinear and parallel to the other transverse bars.

In open flooring of the kind specified, the longitudinal bars are usually intended to bear any imposed downward load, whilst the transverse bars are intended primarily to hold the longitudinal bars in the required relative positions. The transverse bars are spaced further apart from one another than are the longitudinal bars. The longitudinal bars usually have a rectangular cross-section, the longer dimension being vertical in use to provide the required load bearing ability without the use of an excessive quantity of material. In use, the longitudinal bars are directly supported by beams or other suitable supports and the transverse bars are directly supported only by the longitudinal bars.

There is a requirement for open flooring to be constructed with narrow gaps between adjacent bars, in order to reduce the risk of danger to personnel or damage to equipment from objects falling through the flooring, but this requirement conflicts with the requirement to achieve the required load bearing ability with the minimum of material.

According to a first aspect of the present invention, we provide a floor comprising a first set of bars, the bars of the first set being rectilinear, spaced apart and parallel to each other, a second set of bars, each bar of the second set being transverse to the bars of the first set and connecting together more than two bars of the first set, and a plurality of intermediate elements, wherein each intermediate element is elongate, rectilinear and lies between a pair of adjacent bars of the first set, upper edges of the bars of the first set define an upper surface of the floor, all elongate elements which lie between respective pairs of adjacent bars of the first set are arranged with their respective lengths extending in a direction from one bar of the second set to another, each intermediate element is spaced downwardly from said surface and has a cross sectional area in a vertical plane which is smaller than the cross sectional area in a vertical plane of a bar of the first set and each intermediate element lies at least partly below and is attached to a plurality of the bars of the second set.

Preferably, all elongate elements which are disposed between respective pairs of adjacent bars of the first set are directly supported only by the bars of the second set; whereas the bars of the first set are directly supported by supports other than the bars of the second set and the bars of the first set directly support the bars of the second set.

At each position where a bar of the second set is supported by a bar of the first set, the bar of the second set may penetrate into the bar of the first set from the upper edge thereof so that there is a discontinuity in the bar of the first set at the upper surface of the floor; whereas each bar of the second set is continuous along its length at the upper surface of the floor.

According to a second aspect of the invention, we provide flooring of the kind specified wherein the longitudinal bars and the transverse bars are rectilinear and have substantially coplanar edges which collectively define one surface of the flooring. there is provided a plurality of intermediate elements, each intermediate element is elongate, rectilinear and lies between a respective pair of adjacent longitudinal bars, each intermediate element has a cross sectional area in a plane perpendicular to its length which is smaller than the cross sectional area of a longitudinal bar in a plane perpendicular to its length, all elongate elements which lie between respective pairs of adjacent longitudinal bars are arranged with their respective lengths extending in a direction from one transverse bar to another, each intermediate element is attached to a plurality of the transverse bars and each intermediate element is spaced from said surface of the flooring by a distance not exceeding the thickness of the transverse bars.

By the thickness of the transverse bars, we mean that dimension which extends in a direction perpendicular to said surface of the flooring.

Preferably, all elongate elements of the flooring which are disposed between respective longitudinal bars are directly supported only by the transverse bars.

Each transverse bar is preferably continuous along its length at said surface of the flooring, in which case there are discontinuities in the longitudinal bars at said surface of the flooring where the transverse bars cross the longitudinal bars.

According to a third aspect of the invention, we provide a method of producing flooring according to the second aspect wherein a plurality of longitudinal bars are arranged parallel to each other and spaced apart by gaps each containing an elongate element which is parallel to the longitudinal bars, a plurality of transverse bars are brought into contact with the longitudinal bars and secured thereto and the transverse bars are secured to the elongate elements either before or concurrently with securing of the transverse bars to the longitudinal bars.

The transverse bars may be secured to the elongate elements before either of these is brought into the positional relation to the longitudinal bars which subsists in the completed flooring. Thus, there may be applied to the longitudinal bars a grid comprising the elongate elements and transverse bars.

The invention will now be described, by way of example, with reference to the accompanying drawings wherein: FIGURE 1 shows a plan view of flooring in accordance with the invention, FIGURE 2 shows a cross-section of the flooring. and FIGURE 3 illustrates one method of producing the flooring of Figure 1.

Panels of open flooring are normally prefabricated and then transported to the site at which the flooring is to be erected, where the panels are laid side by side on suitable supports. The exptession "open flooring" as used herein refers both to individual panels and to an assembly of such panels which constitutes a complete floor.

The panels are usually rectangular, although panels of different shapes may be fabricated to fit around members which are to extend through the flooring. A part of a panel is shown in Figure 1. This panel includes a plurality of longitudinal bars 10 which are connected together by transverse bars 11. The longitudinal bars are rectilinear and have a rectangular cross-section, the longer dimension of which extends vertically when the panel is horizontal. When the flooring is in use, end portions of the longitudinal bars rest on supports, for example, beams supported by pillars or by walls of a building in which the flooring is provided.

Further supports for the longitudinal bars may be provided between the end portions thereof.

Each of the transverse bars 11 extends across all of the longitudinal bars 10 of the panel and lies in corresponding notches formed in upper edges of the longitudinal bars. The transverse bars are secured to the longitudinal bars by fusion. The transverse bars are directly supported only by the longitudinal bars.

Any downward load which is applied to a transverse bar in use is transmitted to a support through the intermediary of the longitudinal bars 10.

The panel shown in Figure 1 further comprises a plurality of elongate intermedite elements 12 which lie between the longitudinal bars 10, are arranged with their lengths extending from one transverse bar 11 to another and are secured to the transverse bars.

When the flooring is in use, the edges of the longitudinal bars 10 which are adjacent to the transverse bars 11 are the uppermost edges of the longitudinal bars and the intermediate elements 12 lie below the transverse bars 11 and therefore below the uppermost edges of the longitudinal bars. It will be noted that the cross-sectional area of each intermediate element 12 is a plurality of times less than the cross-sectional area of each longitudinal bar 10. Typically, the longitudinal bars have a width of 5mum and a depth of 30mm and the intermediate elements 12 are formed of round wire having a diameter of approximately 7mm. In the particular example of flooring illustrated in the accompanying drawings, the pitch of the longitudinal bars 10 is 30mm and the gaps between the elongate elements and adjacent longitudinal bars are approximately 9mm wide.

In the particular example of flooring illustrated, the longitudinal bars 10, transverse bars 11 and intermediate elements 12 are all rectilinear, the intermediate elements are parallel to the longitudinal bars and lie centrally in the gaps between adjacent longitudinal bars and the transverse bars are perpendicular to the longitudinal bars and elongate elements. The transverse bars may have a substantially square cross-section but be twisted about their respective longitudinal axes.

One method of producing the flooring is illustrated in Figure 3. In this method, the required number of longitudinal bars 10 and intermediate elements 12 are supported in the required relative positions by a support 13. The support is in the form of a platform having in its upwardly presented face recesses 14 for the longitudinal bars 10 and recesses 15 for the intermediate elements 12.

The depth of each of the recesses 14 is less than the depth of the longitudinal bars by an amount approximately equal to the depth of the transverse bars 11 so that the longitudinal bars project upwardly from the support. The depth of each of the recesses 15 is a small amount less, typically 10% less, than the thickness of the intermediate elements 12 so that these elements project only slightly from the support. The support 13 extends along only a part of the lengths of the longitudinal bars and intermediate elements, typically for a distance between one and two times the pitch of the transverse bars Il.

The apparatus for producing the flooring further comprises a pair of electrodes 16 and 17 which are disposed above the support 13 and each has a length approximately equal to the length of the support so that the electrodes extend across the entire width of the flooring to be produced. The electrodes are spaced apart apart in a direction along the lengths of the longitudinal bars 10 so that respective longitudinal centre lines of the electrodes are spaced apart by a distance equal to the pitch of the transverse bars I I.

The electrodes are mounted by means not shown for reciprocation towards and away from the support 13.

With the electrodes 16 and 17 raised clear of the longitudinal bars 10 and intermediate elements 12 supported by the platform 13, two transverse bars 11 are laid across the exposed edges of the longitudinal bars at positions directly below respective ones of the electrodes. The electrodes are then lowered into contact with respective ones of the transverse bars and an electric current is passed from the electrode 16 through the corresponding transverse bar, through the longitudinal bars 10 and the other transverse bar to the electrode 17. This causes resistance heating of the longitudinal bars at the positions where these are crossed by the transverse bars. The transverse bars are forced downwardly by the electrodes to form notches in the upper edges of the longitudinal bars. As the depth of these notches approaches the depth of the transverse bars, the latter come into contact with the intermediate elements 12 and electric current is then conducted by the intermediate elements also so that heating occurs at the positions where the transverse bars cross the intermediate elements. In this manner, the transverse bars are welded to both the longitudinal bars and the intermediate elements with each transverse bar being continuous along its length at the upper surface of the flooring; whereas the longitudinal bars are effectively notched where each transverse bar crosses over them.

Downward movement of the transverse bars is terminated before these engage the support 13.

When one pair of transverse bars have been united with the longitudinal bars and the intermediate elements, the electrodes 16 and 17 are withdrawn upwardly, the longitudinal bars and intermediate elements are advanced by a distance equal to twice the pitch of the transverse bars and a further pair of transverse bars is applied to the longitudinal bars.

In an alternative method of producing the flooring, a grid comprising the transverse bars 11 and the intermediate elements 12 is formed. The transverse bars and the intermediate elements are arranged in the relative positions required in the finished flooring, in particular, the intermediate elements are arranged at a pitch equal to the pitch which is to be established for the longitudinal bars.

The intermediate elements are then secured to the transverse bars by welding. An array of parallel longitudinal bars is then brought into contact with the grid and the relative positions required in the finished flooring is established. The transverse bars are then secured to the longitudinal bars by welding similar to that described with reference to figure 3.

In either of the methods described, the flooring panel may be completed by the provision of additional bars connecting together the free ends of the longitudinal bars.

WHAT WE CLAIM IS:- 1. A floor comprising a first set of bars, the bars of the first set being rectilinear, spaced apart and parallel to each other, a second set of bars, each bar of the second set being transverse to the bars of the first set

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. diameter of approximately 7mm. In the particular example of flooring illustrated in the accompanying drawings, the pitch of the longitudinal bars 10 is 30mm and the gaps between the elongate elements and adjacent longitudinal bars are approximately 9mm wide. In the particular example of flooring illustrated, the longitudinal bars 10, transverse bars 11 and intermediate elements 12 are all rectilinear, the intermediate elements are parallel to the longitudinal bars and lie centrally in the gaps between adjacent longitudinal bars and the transverse bars are perpendicular to the longitudinal bars and elongate elements. The transverse bars may have a substantially square cross-section but be twisted about their respective longitudinal axes. One method of producing the flooring is illustrated in Figure 3. In this method, the required number of longitudinal bars 10 and intermediate elements 12 are supported in the required relative positions by a support 13. The support is in the form of a platform having in its upwardly presented face recesses 14 for the longitudinal bars 10 and recesses 15 for the intermediate elements 12. The depth of each of the recesses 14 is less than the depth of the longitudinal bars by an amount approximately equal to the depth of the transverse bars 11 so that the longitudinal bars project upwardly from the support. The depth of each of the recesses 15 is a small amount less, typically 10% less, than the thickness of the intermediate elements 12 so that these elements project only slightly from the support. The support 13 extends along only a part of the lengths of the longitudinal bars and intermediate elements, typically for a distance between one and two times the pitch of the transverse bars Il. The apparatus for producing the flooring further comprises a pair of electrodes 16 and 17 which are disposed above the support 13 and each has a length approximately equal to the length of the support so that the electrodes extend across the entire width of the flooring to be produced. The electrodes are spaced apart apart in a direction along the lengths of the longitudinal bars 10 so that respective longitudinal centre lines of the electrodes are spaced apart by a distance equal to the pitch of the transverse bars I I. The electrodes are mounted by means not shown for reciprocation towards and away from the support 13. With the electrodes 16 and 17 raised clear of the longitudinal bars 10 and intermediate elements 12 supported by the platform 13, two transverse bars 11 are laid across the exposed edges of the longitudinal bars at positions directly below respective ones of the electrodes. The electrodes are then lowered into contact with respective ones of the transverse bars and an electric current is passed from the electrode 16 through the corresponding transverse bar, through the longitudinal bars 10 and the other transverse bar to the electrode 17. This causes resistance heating of the longitudinal bars at the positions where these are crossed by the transverse bars. The transverse bars are forced downwardly by the electrodes to form notches in the upper edges of the longitudinal bars. As the depth of these notches approaches the depth of the transverse bars, the latter come into contact with the intermediate elements 12 and electric current is then conducted by the intermediate elements also so that heating occurs at the positions where the transverse bars cross the intermediate elements. In this manner, the transverse bars are welded to both the longitudinal bars and the intermediate elements with each transverse bar being continuous along its length at the upper surface of the flooring; whereas the longitudinal bars are effectively notched where each transverse bar crosses over them. Downward movement of the transverse bars is terminated before these engage the support 13. When one pair of transverse bars have been united with the longitudinal bars and the intermediate elements, the electrodes 16 and 17 are withdrawn upwardly, the longitudinal bars and intermediate elements are advanced by a distance equal to twice the pitch of the transverse bars and a further pair of transverse bars is applied to the longitudinal bars. In an alternative method of producing the flooring, a grid comprising the transverse bars 11 and the intermediate elements 12 is formed. The transverse bars and the intermediate elements are arranged in the relative positions required in the finished flooring, in particular, the intermediate elements are arranged at a pitch equal to the pitch which is to be established for the longitudinal bars. The intermediate elements are then secured to the transverse bars by welding. An array of parallel longitudinal bars is then brought into contact with the grid and the relative positions required in the finished flooring is established. The transverse bars are then secured to the longitudinal bars by welding similar to that described with reference to figure 3. In either of the methods described, the flooring panel may be completed by the provision of additional bars connecting together the free ends of the longitudinal bars. WHAT WE CLAIM IS:-

1. A floor comprising a first set of bars, the bars of the first set being rectilinear, spaced apart and parallel to each other, a second set of bars, each bar of the second set being transverse to the bars of the first set

and connecting together more than two bars of the first set, and a plurality ofintermediate elements, wherein each intermediate element is elongate, rectilinear and lies between a pair of adjacent bars of the first set, upper edges of the bars of the first set define an upper surface of the floor, all elongate elements which lie between respective pairs of adjacent bars of the first set are arranted with their respective lengths extending in a direction from one bar of the second set to another, each intermediate element is spaced downwardly from said surface and has a cross sectional area in a vertical plane which is smaller than the cross sectional area in a vertical plane of a bar of the first set and each intermediate element lies at least partly below and is attached to a plurality of bars of the second set.

2. Flooring of the kind specified wherein the longitudinal bars and the transverse bars are rectilinear and have substantially coplanar edges which collectively define one surface of the flooring, there is provided a plurality of intermediate elements, each intermediate element is elongate, rectilinear and lies between a respective pair of adjacent longitudinal bars, each intermediate element has a cross sectional area in a plane perpendicular to its length which is smaller than the cross sectional area of a longitudinal bar in a plane perpendicular to its length, all elongate elements which lie between respective pairs of adjacent longitudinal bars arranged with their respective lengths extending in a direction from one transverse bar to another, each intermediate element is attached to a plurality of the transverse bars and each intermediate element is spaced from said surface of the flooring by a distance not exceeding the thickness of the transverse bars.

3. A floor according to claim 1 wherein the intermediate elements are directly supported only by the bars of the second set.

4. Flooring according to claim 2 wherein the intermediate elements are directly supported only by the transverse bars.

5. A floor according to claim 1 or flooring according to claim 2 wherein the intermediate elements are formed of wire having a substantially circular cross section.

6. A floor according to claim 3 or flooring according to claim 4 wherein each intermediate element lies centrally between said pair of adjacent bars.

7. A floor according to claim I wherein all elongate elements which are disposed between respective bars of the first set are directly supported only by bars of the second set.

8. Flooring according to claim 2 wherein all elongate elements which are disposed between respective longitudinal bars are directly supported only by the transverse bårs.

9. A floor according to any one of claims 1, 3, 5, 6 or 7 wherein each bar of the second set is continuous along its length at the upper surface of the floor.

10. Flooring according to any one of claims 2, 4, 5, 6, or 7 wherein each transverse bar is continuous along its length at said surface of the flooring.

I I. A method of producing flooring as claimed in claim 2 wherein a plurality of longitudinal bars are arranged parallel to each other and spaced apart by gaps each containing an elongate element which is parallel to the longitudinal bars, a plurality of transverse bars is brought into contact with the longitudinal bars and secured thereto and the transverse bars are secured to the elongate elements either before or concurrently with securing of the transverse bars to longitudinal bars.

12. A method according to claim 11 wherein the longitudinal bars are supported with corresponding edges in a plane, the elongate elements are supported in respective positions spaced from said plane, the transverse bars are applied to said corresponding edges of the longitudinal bars and are then moved relative to the longitudinal bars in a direction towards the elongate elements to deform the longitudinal bars and establish contact between the transverse bars and the elongate elements.

13. A method according to claim 11 comprising the step of making a grid by arranging the transverse bars parallel to each other and each crossing the elongate elements and securing each transverse bar to each of the elongate elements and then bringing the longitudinal bars into contact with the transverse bars and securing the longitudinal bars to the transverse bars where such contact is established.

14. Open flooring substantially as herein described with reference to and as shown in the accompanying drawings.

15. A method of producing flooring according to claim I substantially as herein described with reference to Figure 3.