Year: 1886

page_text: Date of Application, 20th Aug., 1886.
Complete Left, 2nd Mar., 1887.
Complete Accepted, 5th Apr., 1887.
I, EDMUND EDWARDS, of the firm of Edwards and Co., Patent Agents and
Engineers, of 35, Southampton Buildings, Chancery Lane, in the County of
Middlesex, do hereby declare the nature of this invention to be as follows:-
In iron girders having T-iron flanges, as ordinarily used for the floors of buildings,
it is impossible to nail the flooring boards directly upon the girders, and the
present invention has for its object a novel method of making such girders so
that the boards may be nailed directly and easily upon them.
The improved girder consists of a central plate or web, having rolled upon it
if required one or more central lateral flanges for supporting intermediate beams or
boards, and a double lower flange, a short distance above which may also be made
small lateral ribs between which and the lower flange the edge of the ceiling boards
fit, or which may assist in supporting masonry arches or vaulting of the usual
kind when used between the girders.
The upper edge of the girder is provided with a lateral flange of the usual kind
upon one side, whilst upon the other side a similar flange is also provided but at
a somewhat lower level than the opposite one, a supplementary rib or strip of
cast or wrought iron being fitted upon this lower flange, to which it is bolted
or rivetted.
The upper surface of this supplementary rib is level with the opposite flange, but its
inner edge is situated at a short distance from the body of the girder, the longitudinal
space thus formed being continued round under the inner edge of the strip and thence
up for a sufficient distance into the body of the latter.
It will be seen that if planks or flooring boards are laid over the upper edge of
the girder, nails can be driven through them the points of which enter the narrow

page_text: longitudinal space described, and as they are driven in are deflected round and
up into the body of the longitudinal strip so as to be firmly held.
Instead of the longitudinal space between the inner edge of the strip being
continuous it may be divided into a number of contiguous vertical grooves or
channels separated by narrow intermediate ribs which come in contact with the
main girder.
The lower of the flanges described at the upper edge of the girder may have
its outer edge bent up and over so as to form an inner groove or recess into which the
outer edge of the strip or rib (which is made of corresponding shape) is forced when
the nails are driven in between it and the girder, and in this way no bolts or
rivets are necessary.
Or the strip or rib may be bolted or rivetted to the depressed flange as first
described, but may have its outer edge formed of a similar shape to its inner
edge to receive the points of nails, so that either edge may be used as desired.
The lower flange of the girder may be formed and provided with a supplementary
strip or rib in the same way as the upper flange.
Instead of the rib or strip described being supported by and attached to a depressed
flange as described, the latter may be omitted altogether, and the rib or strip may be
bolted or rivetted to the central body or web of the girder.
The upper edge of the longitudinal space between the girder and the rib or
strip is preferably widened or countersunk, in order that the points of the nails
may more readily enter it.
725
1

page_text: In figure 6 a modification is represented in which the supplementary rib J is fixed
directly by means of rivets or screw bolts to the centre rib N, the corresponding half
of the upper flange being omitted.
Having now particularly described and ascertained the nature of my said Invention,
and in what manner the same is to be performed, I declare that what I claim is :-
--
A combined trussed girder of rolled iron with its channelled supplementary rib of
rolled or cast iron, which is fixed upon one half of the upper flange and upon which
the boards rest directly, and the modifications of this arrangement as herein described
and shewn in the drawings.