Improvements in the Construction of Floors, Arches, and the like, and in Centres therefor.
Year: 1899

page_text: Date of Application, 15th Aug., 1899-Accepted, 14th Oct., 1899
COMPLETE SPECIFICATION.
Improvements in the Construction of Floors, Arches, and the like,
and in Centres therefor.
I, ALBERT HENRY BROMLEY, Junior, of 2425, Kimball Street, in the City and
County of Philadelphia, and State of Pennsylvania, United States of America,
Engineer, 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:-
My invention relates to a class of devices employed in the builders' art, and
termed centres" in the nature of arciform bodies designed to be placed upon
the piers or between the girders or other foundations upon which an arch or
cognate superstructure is to rest, and to serve to support the arch during the
process of construction until it becomes self-supporting.
My invention is of especial utility, although not restricted to such use,―in
the construction of the floorings of fire proof buildings in which masses of cement
are employed to fill in the spaces between the girders.
Heretofore centres have been built up of wood, formed of wire cloth, or of wire
cloth covered with cementaceous material, or of various other woven or manually
formed constructions, which have involved considerable expenditures of time and
money.
It is the object of my invention to provide a centre, which shall be strong,
inexpensive, and easily made and handled.
Generally stated, my invention resides in the provision of a centre formed of
a plastic or kindred material, which, without dies or presses may be easily shaped
to the required form, and which, when shaped, will readily set or harden into
condition for immediate use.
A desirable type of a plastic quick-setting material from which the centres
may be made, is plaster of Paris combined if necessary with a suitable binder such
for instance, as papier mache, hair, excelsior, or burlap.
It will, however, be understood that my invention is not restricted to a plastic
quick-setting material formed of these materials but that it includes other suitable
materials.
c
The form to which the centre is shaped, as well as the especial application of
it when made, may vary widely.
In the drawings I show several distinct forms alike embodying my invention.
Figure 1 is a sectional elevation of a typical floor.
Figure 2 is a view in perspective of the centre employed in the construction
of the floor of Figure 1.
Figure 3 is a sectional elevation of a typical floor.
Figure 4 is a view in perspective of the modified form of centre employed in
the construction of the floor of Figure 3.
Figure 5 is a sectional elevation of a typical floor illustrating the employment
of still another modified form of my improved centre.
Figures 6 and 7 are views in perspective of additional forms of modified
centres.

page_text: Similar letters of reference indicate corresponding parts.
In Figures 1, 3, and 5, of the drawings, A represent girders or I-beams, B the
floor joists laid upon the same, C the flooring boards, and 1) the cement filling
all of any ordinary character.
In the use of centres in the construction of fire proof flooring, the centres, as
is well known, are first put in place with their respective side-edges resting upon
the opposing lower flanges of adjacent girders, and the cement or other material
is laid upon them in such quantity as may be desired, and usually until it is
approximately level with the upper surfaces of the I-beams.
As is also well-known, the cement will harden, set, and become self-supporting,
after it has been placed in position, and the centre may thereupon, if desired, be
removed by cutting it through the middle with a saw or breaking it out with a
hammer or other implement.
When, however, the centres are made of plaster, or kindred material, in accord-
ance with my invention, they afford a very convenient surface for ornamentation,
and their lower faces may be formed or provided with any desired surface to
form a permanent ornamental ceiling for the apartment below, or said lower faces
may be employed as such ceiling without ornamentation.
The centre E shown in Figures 1 and 2, is a long strip in the form of a segment
of a cylinder, that is to say, straight from end to end, but curved or arched from
edge to edge.
The centre F shown in Figures 3 and 4, is in the form (in plan) of a square, is
arched upward on all sides, and is of a breadth equal to the distance between the
lower flanges of the adjacent I-beams in connection with which it is to be used,―
a series of these centres being disposed in succession from end to end of the
beams.
The centre G shown in Figure 5, corresponds to that of Figures 1 and 2, with
the addition of a flat horizontal web g preferably of the same material as the
arched web g, which extends from edge to edge of said arched web, and is
arranged to be approximately flush with the lower faces of the I-beams, so that
upon covering being applied to the lower faces of the I-beams, a uniform flat
horizontal ceiling will be formed for the apartment below.
The centres may, of course, be in section, of forms other than that of an arch,
as illustrated by the modified forms H shown in Figures 6 and 7, the essence of
my invention consisting not in any particular form of centre, but in the employ-
ment in the construction of centres of various forms whether arched as in
Figures 1 to 5, or quasi-arched as in Figures 6 and 7, of plastic quick-setting
material.
My improved centres of the form shown in Figure 1 may be quickly and easily
formed by supplying a sufficient quantity of the selected plastic material within
an open-topped trough-like receptacle the bottom of which has the form it is
desired to impart to the lower face of the centre, and the wall of which is of height
corresponding to the thickness it is desired that the centre shall possess,-by
then resting a straight edge upon the end walls of the trough and moving the
same transversely from edge to edge of said trough, thus levelling off the upper
surface of the plastic material flush with the upper edge of the wall of the
trough, and by finally removing any excess of the material.
My improved centre formed of a quickly-molded and set mass of plastic material
constitutes a very great improvement over existing devices of the same class
which are built up of several parts and require much labor in their formation
and erection and the use of quite expensive materials.
The materials of which my improved centre is made are inexpensive, the time
required for its production is very short, and the apparatus required very
simple.
When finished the centre is very easily handled and transported, and where
any fitting to adjust it to its supports is required, it may be very quickly and
easily cut with a saw or otherwise.

page_text: The essence of my invention may be stated to consist in the formation of
centres and similar devices from plastic quick-setting material, such centres
being molded or formed in advance of being placed in position in the structure
in which they are used.
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:
1. As an article of manufacture, a centre completed in advance of being placed
in position, formed of plastic quick setting material, and adapted to support an
overlying mass of building material, substantially as set forth.
2. A centre formed of plaster of Paris and papier mache, substantially as set
forth.
3. As an article of manufacture, a centre, completed in advance of being placed
in position, formed of plaster of Paris, or equivalent substance, and adapted to
support an overlying mass of building material, substantially as set forth.
4. As an article of manufacture, a centre completed in advance of being placed
in position, formed of plastic quick-setting material combined with a suitable
binding material, and adapted to support an overlying mass of building material,
substantially as set forth.
5. As an article of manufacture, a centre completed in advance of being placed
in position, formed of plaster of Paris combined with a suitable binder, and
adapted to support an overlying mass of building material, substantially as set
forth.
6. A flooring structure composed of I-beams, centres formed in advance of
being placed.in position, of plaster of Paris or similar quick setting material
combined with a suitable binder, resting on said beams and forming the ceiling
of an apartment below, and a cement filling in the space above said centres and
extending from I-bean to I-beam, substantially as set forth.
ALBERT HENRY BROMLEY, JUNIOR.
Witnesses:
This day of July A.D. 10.
FREDERIC NORMAN DIXON.
THOMAS KEYS LANCASTER.