AU2004235640B2

AU2004235640B2 - Improvements in tray flooring

Info

Publication number: AU2004235640B2
Application number: AU2004235640A
Authority: AU
Inventors: Alan Harry Newman
Original assignee: Individual
Current assignee: Individual
Priority date: 2003-12-12
Filing date: 2004-12-06
Publication date: 2007-08-16
Anticipated expiration: 2024-12-06
Also published as: AU2004235640A1

Description

4 01 ci o IMPROVEMENTS IN TRAY FLOORING INC This invention relates to an improvement in high strength steel tray flooring to be used as part of a composite Sfloor slab with concrete as the upper layer.

ci o My New Zealand Registered Design No. 400950 shows a floor Ci tray with indentations formed into the upright web portions. Those indentations are intended to bind to the concrete poured into the tray so that there is no creep between the concrete and the tray so that the whole structure acts as a single unit. The steel tray, of course, is under tension in a non-cantilevered situation and the concrete slab could include internal reinforcing to ensure that it held together in the event of a fire destroying the load-carrying capacity of the steel tray component. A composite slab has a greater fire rating than would the tray if exposed alone because of the heat conducted away by the concrete.

With my previous design, the indentations protruded equally on either side of the upright web. This meant that the webs of adjacent trays had to be nested together so that the protrusions and indentations meshed together.

While this worked perfectly satisfactorily it did require extra care in the cutting of each floor pan so that intermeshing of the indentations and protrusions could occur and also involved care to ensure that in the installation of adjacent floor pans appropriate meshing was achieved.

It was therefore an object of the present invention to devise a floor pan which did not have the above-mentioned Mdisadvantages, or at least which provided the public with a useful choice.

The present invention consists in a method of making a floor pan having a plurality of webs where, during the rolling process, an inwards facing bulge is rolled into each web and the bulge is subsequently crushed by means of spur gears or similar, or pressed so that the indentations and protrusions lie substantially wholly in the inward facing sides of each web.

The invention also relates to a product which is manufactured by the above method.

Referring to Figure 1, my New Zealand Registered Design No.

400950 shows a cross section (between indentations and protrusions) in a high strength steel floor pan having Supstanding webs 2 and 3. It can be seen that the protrusions such as 4 or 5 extend on both sides of a web 0such as 2. The resultant product is illustrated by the Va operspective view shown in Figure 2 where the sectioning oacross the tray has been done at the intersection of an indentation and protrusion. Thus, looking at the web 3, en c-i one sees a protrusion 6 and indentation 7, a protrusion 8 o and so on along the length of the web viewed from the ci outside.

The improvement is illustrated in Figures 3 and 4 where Figure 3 shows a cross section through a high strength steel floor pan after the first rolling stage and Figure 4 shows a cross sectional view after inwardly facing protrusions have been formed in the webs by suitable means.

Thus, in the manufacture of a high strength steel floor pan 9 the improvement consists firstly in the formation during the rolling process of inwardly facing elongated bulges 10, 11 in respective webs 12, 13. The object is to gain the maximum amount of inward protrusion consistent without splitting the steel during a subsequent crushing process, using pairs of mating spur gears (not shown), or a press, for instance on either side of each web.

ci o The teeth of each inside spur gear press the bulges 10,11 0back to the alignment of the remainder of the web 12 or

VO

O 13, while the teeth of the outside spur gears maintain the obulges projecting inwardly of the web. Thus there are Va O formed a series of inward projections such as 14, 15 at en Ci about 25mm intervals having a depth of about 3mm or more.

oWith 0.75mm or 0.95mm 550Mpa steel I actually can achieve ci a depth of 5.5mm or more.

One strives for the maximum depth consistent with retaining the integrity of the floor pan. Because there are no protrusions to the outside of the webs 12, 13, interlocking pans can be snap-locked together without undue care needing to be taken about their longitudinal alignment. This simplifies the cutting of the floor pans and the installation of them.

The method of forming the protrusions also provides a bond with the concrete which is probably superior to that achieved with the construction of my aforementioned New Zealand Design registration.

Claims

2. A method as claimed in claim 1 wherein the crushing is effected by means of spur gears.
3. A method as claimed in claim 1 wherein the crushing is effected by pressing.
4. A method of making a floor pan substantially as herein described with reference to Figures 3 and 4. A floor pan when made by the method as claimed in any one of claims 1 to 4.