Year: 1886

page_text: We, HEINRICH STOLLWERCK, and LUDWIG STOLLWERCK, of the firmn of Gebruder
Stollwerck, of Cologne-on-the-Rhine, in the Empire of Germany, Manufacturers do
hereby declare the nature of our invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
Our invention relates to staircases and has for its object to obviate the dis-
advantages and constructional difficulties heretofore exists in fireproof and other
staircases of various and well-known kinds.
Our said invention therefore consists in providing an improved staircase com-
posed essentially of supports or beams of suitable section with an intervening
filling of concrete, all as hereinafter described.
Our improved staircase possesses the advantages of great durability, of affording
sufficient safety against fire for all practical purposes, and of being easy of ascent,
inasmuch as no obstacles are presented to the feot of the person or persons
ascending the same.
The invention is illustrated in the accompanying drawing, in which
Figure 1 is a side view of part of the improved staircase.
Figure 2 is a side view of part of a staircase of a somewhat modified construction.
Figure 3 is a transverse section on the line x, x, Figuro 1.
Figure 4 is a side view illustrating the manner in which the improved staircase
is constructed.
The improved staircase is made of beams constructed either of rolled iron, or
other suitable material such as pressed paper or wood pulp; the said supports
or beams being connected in a peculiar manner by means of cement concrete.
This concrete is filled into the spaces between the said supports or beams while in a
soft state, so as to cover or embed the latter fully on one side and partly on the
other side, and to firmly connect the said supports or benins after the intervening
mass of concrete becomes dry, hard and solid, and thus to hold them in position.
Referring to the accompanying drawing, the intermediate bodies a of concrete
forming the stepping surfaces, are carried or held by the supports or beams b, the
latter admitting of any suitable sectional shape such, for instance, as shewn in
Figures 14, 1b or 1° and forming, on their part, the vertical surfaces of each step
or stair.

page_text: When the staircase is to be built between two walls, the supports or beams b are
sunk into such walls, the latter serving as the carriages of the staircase.
Preparatory to filling in with concrete, a bottom u, Figure 4, of boards is pro-
vided below the supports b, in such a manner as to support the mass of concrete
which is filled in from above. The filling with concrete may be commenced either
from the foot of the staircase or from the head. As soon as the several bodies a of
concrete have become sufficiently hardened, so as to form, with the intervening
supports or beams b, one coherent solid mass (which generally requires but a few
days time), the board bottom is taken away and the staircase remains as shewn in
Figure 1.
In cases where the position of the staircase does not admit of using the walls of
the building as side supports or carriages, and it becomes necessary to provide
special carriages e for the staircase, angular pieces d, Figure 2, of iron are mounted
on the said carriages e, thus serving as seats or bearings for the supports or beams b.
In every other respect the construction is the same as already described.
The surface of the concrete of the several stairs may be smoothened, ornamented,
coated or covered with wood, india-rubber or other desirable material in the well-
known manner.
The advantages of the improved staircase above described, as compared with
staircases of other constructions, are evident, especially since the concrete used in
its construction improves in hardness and solidity from day to day, thus securing
additional durability and carrying capacity, and offering every possible safety in
case of fire. Another material advantage in the improved staircase is to be found
in the fact that the projecting part m of each stair forms a hollow space below it,
sufficiently large to prevent the feet of persons ascending the stairs from forcibly
striking against the vertical portion n.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is :-
First A staircase composed essentially of supports or beams having the section
shown in Figures 1ª, 1 or 1°, or any other suitable section, and of cement concrete
substantially as described,
Second: In a staircase, the combination, with the supports or beams b forming
the vertical faces of each stair, of an intervening mass or filling a of concrete in
which the said supports or beams are more or less embedded, and by which they
are rigidly held together, the upper surface of said mass forming the horizontal
stepping surface of the step or stair, substantially as described.
Dated this 20th day of August 1886