AN IMPROVED MECHANICAL BEAM OR GIRDER
Year: 1872

page_text: LETTERS PATENT to Antonio Joaquim Pereira de Carvalho, of
Buckingham Palace Road, in the County of Middlesex, Gentleman,
for the Invention of "AN IMPROVED MECHANICAL BEAM OR GIRDER.”
Sealed the 14th March 1873, and dated the 23rd September 1872.
COMPLETE SPECIFICATION filed by the said Antonio Joaquim Pereira
de Carvalho, at the Office of the Commissioners of Patents, with
his Petition and Declaration, on the 23rd September 1872, pursuant
to the 9th Section of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ANTONIO
JOAQUIM PEREIRA DE CARVALHO, of Buckingham Palace Road, in the
County of Middlesex, Gentleman, send greeting.
WHEREAS ‘I am in possession of an Invention for “AN IMPROVED
MECHANICAL BEAM OR GIRDER," and have petitioned Her Majesty to
grant unto me, my executors, administrators, and assigns, Her Royal
Letters Patent for the same, and have made solemn Declaration that I
am the true and first Inventor thereof.

page_text: NOW KNOW YE, that I, the said Antonio Joaquim Pereira de
Carvalho do hereby declare that the following Complete Specification,
under my hand and seal, fully describes and ascertains the nature
of the said Invention, and in what manner the same is to be performed,
in and by the following statement (that is to say) :-
My Invention consists in the construction and employment of
mechanical beams made of any kind of materials, such as iron, bronze,
wood, or otherwise, which may be found suitable for the nature of the
work required, thus the pieces hereafter described will be made in
conformity with the extension of the construction to which the
mechanical beams are to be applied, combined with the resistance of
the materials to be used in accordance with existing experiments.
I take boards or plates of the length, width, and thickness, which
will be found convenient for the extension and resistance which the
mechanical beams have to bear and attain. Some of these planks or
plates will be rectangular, Fig. 1, and others will be cut diagonally at
their extremities with a tooth, Fig. 3, or plain, Fig. 2. The form of the
tooth may vary; some of these planks or plates will be cut in the
middle in order to have half planks; I make under arms, Fig. 5, b, 11,
and 12, the exterior form of which may vary; the under arms should be
made of iron, for it is on the strength of the under arms that the safety
of the mechanical beams essentially depend. I make iron bars of equal
height with the under arms, Fig. 4; these bars serve for holding or fixing
the planks or plates at the beginning and at the end of the mechanical
beams. These bars will be placed at the top and will have two holes, 2
which are to be made in conformity with two other holes which are to
hold the planks or plates, Figs. 2 and 8; at either of the ends of
mechanical beams I make single washers or studs, Fig. 7, and double
studs, Fig. 8, to be joined between the planks or plates in cavities
which may be opened in the same planks in the interior part of their 3
joints. These cavities must have in depth half of the thickness of the
planks or plates, and for this reason the thickness of the studs must
be equal to the thickness of the planks or plates in which the studs
must be inserted.
In all these planks there must be made two cavities for the single 3
studs, at the quarter of the length of the planks, but not in the middle;
these cavities are to be made in the middle of the width of the planks

page_text: Fig. 1, and as the planks or plates, Figs. 2 or 3, are to be introduced
through the perpendicular openings of the under arms, the cavities
which are to be made in these planks for the single studs must be
made at the same distance of the quarter of the length of the plank,
but higher up.
If preferred the tooth planks may have these cavities or not, in order
to leave to these planks or plates all their natural resistance; besides
these cavities for the single studs, I make in the planks, Fig. 1, cavities
for the double studs at the border edge of these said planks, that is to
say, two cavities in the middle of the planks, and half a cavity in each
of its corners in the way shown in the plank, Fig. 1; these planks will
be introduced in the horizontal openings of the under arms, and the
planks or plates, Fig. 2 and 3, will be introduced in the other
perpendicular openings.
As the mechanical beams or girders made with under arms having
three openings are the most difficult to construct I will give a description
of its construction. The knowledge of the constructions of this kind of
mechanical beams or girders will give clearly the means to construct
easer ones, that is to say, for constructing mechanical beams with the
under arms having one or two openings, I will place at the top one
under arm, Fig. 6, and in its horizontal inferior opening I push through
a plank and half a plank, Fig. 1, with their single and double studs, I
then make the same operation for the horizontal superior opening of
the same under arm; beforehand two parallel openings or slots must
be made in each left end of these two planks and half planks, Fig. 1;
in order to pass through these openings two iron bars, Fig. 4, the space
remaining between these two parallel slot openings must be in the
centre and of the same width as the thickness of the plank and half
plank, Figs. 2, and which are to be passed afterwards with their single
studs through the perpendicular openings of the above mentioned
under arms, and through the middle of the two iron bars placed at the
top untill the two holes of the bars adjust themselves with the two holes
which have been made before in each left end of the plank, and half plank
or plates, Figs. 2 and 3; afterwards two screws are to be passed through
these four pieces and fixed by their screw nuts, having introduced the
filling pieces in the superior and inferior spaces which remained between
the iron bars and the under arms. The filling pieces which are to be.
placed in the superior spaces must be grooved so as to bind themselves.

page_text: on the superior and inferior part of the planks or plates introduced
through the perpendicular openings of the under arms, in a manner that
the grooved filling pieces may serve as supports for the planks, Fig. 1,
introduced through the horizontal openings of the under arms.
The grooved filling pieces which are to be placed in the inferior spaces
must bind themselves in the inferior part of the same planks or plates,
Fig. 2. The form of these said filling pieces is indifferent provided they
fill the essential condition of binding themselves upon the vertical
planks or plates and between the horizontal ones. The beginning of
these three sections of planks being introduced through the three
openings of the under arms, cach section shows the half of a plank or
plate uncovered; in the cavities of the uncovered halves of these planks
or plates I insert the single and double studs, and after that I place
similar planks to those serving to construct their first section; at the
same time in each empty space a piece of filling up is to be introduced,
then an under arm, and so on until the other extremity of the mechanical
beam or girder is to be constructed. When one section of planks has
been began with half a plank this section must end by a whole plank,
and vice versa, when one section of planks or plates has been begun
with a whole plank or plate this section must finish with a half one, the
length of the different sections of planks or plates of which one desires to
compose the mechanical beam remains in this way equal in the whole of
their length. The mechanical beams formed of the different pieces
which compose them having attained the desired length, I introduce
the last under arm, after that the last filling pieces are introduced; then!
there will be passed at the top as in the beginning two iron bars
through the slot openings which ought to have been made beforehand in
the last planks and half planks or plates introduced by the horizontal
openings of the under arms, having also made before two holes in the
right end of the last plank and half plank or plates introduced through
the perpendicular openings of the under arms, I pass two screws fixed by
their screw nuts through these holes. It is essential that the cut of the
planks or plates, Fig. 2 and 3, be diagonal, and as the said planks are to
be introduced through the perpendicular openings of the under arms in
the arrangement of the planks the diagonal cut of the right side of
the plank or plate that precedes may serve as supports to the diagonal cut
of the left side of the following plank; each plank or plate is to be
embraced at least by four under arms at distances well regulated by the

page_text: length of the filling pieces, and the greater the number of under arms
introduced in the planks or plates, the shorter the length of the filling.
pieces, the greater will be the strength of the mechanical beams.
The above description applies only to the construction of mechanical
beams or girders in a straight line; if it be wished to give them a curve
this may be done by the alteration in the diagonal cut of the planks or
plates which are to be introduced through the perpendicular openings of
the under arms, and this alteration of the cut may be made according to
the rules known in architecture. I construct also mechanical beams by
fitting inside of them iron beams like those which are actually made by
Mather, Ledward, & Co., of Liverpool, and other manufacturers, with ribs
and top flanges, Fig. 9, or with ribs, tops, and bottom flanges, Fig. 10,
then I use under arms with one general opening, that is to say, Fig. 11
for the iron beams, Fig. 9, and Fig. 12 for the iron beams, Fig. 10. The
flanges of these iron beams have the same effect as one section of planks,
Fig. 1; at the outside part of these flanges must be made the cavities
above described and which are seen in the planks, Fig. 1; in order to
introduce in these cavities half of the thickness of the single and double
studs when the other section of planks, Fig. 1, will be fitted in these
iron beams must have a diagonal cut as the planks, Fig. 2 and 3; if the
out of these iron beams is rectilinear I would open in the extremities of
their ribs a half circle, and as by the junction of two iron beams the two
half circles would form a whole circle, I introduce in these circles a
rundle of iron of equal thickness with the ribs; in the ribs of each iron
beam there will be opened two holes corresponding with the two cavities
described, and which are seen in the planks, Fig. 2 and 3, in order to
introduce in these holes the single studs which in this case must be
augmented in thickness in order to be just as thick as the rib in which
they are to be fitted, so that the studs may be introduced in the same
holes and the ends of the same studs introduced in the cavities of the
planks or plates, Figs. 2 and 3, which are to fit on each side of the iron
beams. The planks and half planks or plates with which I would begin
the mechanical beams must have a rectilinear cut at their left ends, and
the planks and half planks or plates with which I finish the mechanical
beam must also have a rectilinear cut at their right ends; when plates of
any kind of metal are to be used there are not to be any simple or double
studs, and for this reason, there are not to be any cavities in the planks
or plates; in that case the planks, Fig. 1, will be substituted by the

page_text: planks or plates, Fig. 13, which being placed longitudinally insert
themselves one within the other, and these insertions will be embraced
and held together by the under arms; I also make single under arms as in
Fig. 14, and introduce them in the planks or plates jointed by their
extremities as before described.
I make in like manner mechanical beams in right lines, but these
beams bend themselves lateraly because they have not the adjunction of
flanges, that is to say, the planks which make the single or double T ;
one, two, or more sections of planks or plates can be placed side by side
within the under arms, Fig. 14; in placing these mechanical beams in
the manner that the opening of the under arms, Fig. 14, be horizontal
against two walls or piles they will become curved. After that I will
fill in the spaces between the under arms with materials, but the filling
pieces placed upon the extremities of these mechanical beams must be
attached to them by screws with their nuts.
I claim as my Invention the joining of planks or plates longitudinally
together end to end, and side to side, by means of locking studs and
teeth, the said planks and teeth pieces being introduced through pieces
which I call under arms, which are to hold together and firmly maintain
the general construction of the mechanical beams in the manner above
set forth and described.
In witness whereof, I, the said Antonio Joaquim Percira de
Carvalho have hereunto set my hand and scal, this Seventeenth
day of September in the year of our Lord One thousand eight
hundred and seventy-two.
A. J. PEREIRA DE CARVALHO. (L.S.)