Improvements in Treads or Coverings for Stairs, Landings, Subways, Sewer Outlets, and the like, applicable also to Top Lights.
Year: 1897

page_text: Date of Application, 11th Dec., 1897-Accepted, 26th Mar., 1898
Improvements in Treads or Coverings for Stairs, Landings, Subways,
Sewer Outlets, and the like, applicable also to Top Lights.
We, JOSEPH THOMAS ANDREWS, Civil Engineer, of Gracechurch Street Buildings,
Gracechurch Street, in the City of London, and GEORGE EDWARD MONTAGNON, Civil
Engineer, of Gracechurch Street Buildings, aforesaid, do hereby declare the nature
of this invention and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement:-
This invention consists of a new or improved construction of treads or coverings for
stairs, landings, subways, sewer outlets, and the like, applicable also to top lights, the
said treads and the like, being very economical in first cost, readily manufactured to
any required size, and of a character which will afford a very secure foothold, when
the invention is applied to treads and like coverings.
We will describe our invention as applied to treads and like coverings from which
its application to top lights will also be understood.
According to our invention we make the support, or foundation (which contains the
material constituting the surface of the tread or covering) of metal plate of such a
character and thinness that it can be embossed between a die and counterpart formed
respectively with projections and recesses which will form in the plate series, or rows,
of square, or other shaped recesses, to contain and hold the material formning the
surface of the tread or covering. Other recesses are also formed deep enough to
constitute strengthening ribs, or girders, these being arranged longitudinally,
transversely, diagonally, or otherwise as desired. We will describe our invention with
reference to the accompanying drawings.
Figure 1 is a plan shewing part of a tread or covering constructed in accordance
with our invention. Figure 2 is a cross section. Figure 3 is a cross section of the
die and counterpart with a plate which has been embossed between them. Figure 4
represents a tread constructed in accordance with our invention when arranged as a
self supporting tread that is to say without other support beneath it than the
brackets upon which its ends rest. Figure 5 shews a tread constructed in
accordance with our invention when supported by stone or wood such as a worn step
beneath it.
The plate forming the support or foundation for the material constituting the
surface of the tread or covering is preferably of wrought steel of a thickness of about
say one sixteenth to one eighth of an inch although we do not limit ourselves to this
material and thickness as they may be varied, provided that the metal and thickness
be such as will allow of the plate being "upset," or embossed, between a die and
counterpart formed respectively with projections and countersinks corresponding to
the recesses to be formed in the plate. The said recesses a are shewn as being square
but they may be of other shape provided they do not extend lengthwise as one
recess, or trough, from end to end, or side to side, of the tread, or covering, as it is
one of the objects of this invention to provide a tread, or covering, which presents a
surface which is not continuous either longitudinally or transversely. At intervals
however we make deep recesses, or troughs, b, which constitute the aforesaid

page_text: strengthening ribs or girders to carry the loal coming upon the tread, or covering.
These deep recesses may be formed by providing the die with a removable piece c
which will first depress the metal into the deep recesses of the counterpart and
afterwards the parts which form the recesses a will come into action. Into the
recesses thus formed the material which is to form the surface of the tread, or
covering, is inserted the said material being in pieces d corresponding to the form of
the recesses in the embossed plate & of a depth such that they project some little
distance above the tops of the parts of the plate around the recesses and leave spaces
or grooves e between the several pieces so projecting and as these spaces or grooves
occur both longitudinally and transversely a very firm foothold is secured. The treads,
or coverings, thus made can be used as shewn in Figure 4 so that they are self
supporting as the deep grooves or recesses constitute supports, or girders, which
give great strength and rigidity to the tread, or covering. When however they
are applied to supporting surfaces such as steps, or the like, grooves may be cut in
the said supporting surfaces as shewn in Figure 5 to receive the said supports or
girders, so that the said grooves so cut net as retainers to keep the tread, or covering,
in place and prevent undue strain on screws, or other securing devices, if such be
used. The tread or covering if applied to a bed of cement, is, owing to the embossed
character of its underside held firmly in place by the cement or other plastic material.
Holes may be punched in the plates as at f so as to turn up flanges to give a more
secure hold for the material placed in the recesses.
If the material forming the surface of the tread or covering be made in pieces to be
placed in the recesses in the embossed plate the recesses may be made somewhat
larger at top than at bottom. Or said material may be run into the recesses whilst in
a molten condition and the longitudinal and transverse grooves be formed in the
casting process or by cutting or planning them out from the material.
In this case
if the embossed plate hasholes through it, it will be placed on a surface which will retain
the molten material in the recesses until set.
It will be evident that if the pieces of material placed in the recesses be
transparent the device will constitute a top light.
Having now particularly described and ascertained the nature of this
invention and in what manner the same is to be performed we declare that what
we claim is :
Treads or coverings for stairs, landings, subways, sewer outlets, top lights and the
like, having the support or foundation made from thin metal plates einbossed between
a die and counterpart so as to form recesses for holding the material constituting the
surface of the thread or covering or for the passage of light and with deeper recesses
which also contain such material and constitute strengtheners supports or girders
substantially as and for the purposes herein before described and illustrated by the
accompanying drawings.
Dated this 11th day of Dreamber 1907
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.