IMPROVEMENTS IN THE MANUFACTURE OF SCREWS AND SCREW KEYS, AND THE CONSTRUCTION OF BRIDGES, APPLICABLE TO FLOORINGS, ROOPINGS, AND PAVING
Year: 1852

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JAMES
WARREN, of Montague Terrace, Mile End Road, and BERNARD PEARD
WALKER, of North Street, Wolverhampton, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Royal Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Eighteenth day of
September, One thousand eight hundred and fifty-two, in the sixteenth year
of Her reign, did, for Herself, Her heirs and successors, give and grant unto
us, the said James Warren and Bernard Peard Walker, our exors, adiñiors,
and assigns, Her especial licence, full power, sole privilege and authority, that
we, the said James Warren and Bernard Peard Walker, our exors, adñiors,
and assigns, or such others as we, the said James Warren and Bernard
Peard Walker, our exors, admors, or assigns, should at any time agree with,
and no others, from time to time and at all times during the term of years
therein expressed, should and lawfully might make, use, exercise, and vend,
within England, Wales, and the Town of Berwick-upon-Tweed, our Inven-
tion of "IMPROVEMENTS IN THE MANUFACTURE OF SCREWS AND SCREW KEYS, AND
THE CONSTRUCTION OF BRIDGES, APPLICABLE TO FLOORINGS, ROOPINGS, AND
PAVING;" in which said Letters Patent is contained a proviso that we, the
said James Warren and Bernard Peard Walker, or one of us, should cause a
particular description of the nature of our said Invention, and in what
manner the same is to be performed, by an instrument in writing under
our hands and seals, or under the hand and seal of one of us, to be

page_text: enrolled in Her said Majesty's High Court of Chancery within six calendar
months next and immediately after the date of the said in part recited Letters
Patent, as in and by the same, reference being thereunto had, will more fully
and at large appear.
NOW KNOW YE, that in compliance with the said proviso, we, the said
Jaines Warren and Bernard Peard Walker, do hereby declare that the nature
of our said Invention, and the manner in which the same is to be performed,
are fully described and ascertained in and by the following statement thereof,
reference being had to the Drawings hereunto annexed, and to the figures and
letters marked thereon, that is to say:-
Our Invention consists of certain arrangements by means of which the
manufacture. of cast screws is much improved and economised, and the
machines used in the manufacture are rendered-more effective.
The first of these improvements consists in the use of guide screws of a finer
pitch than that of the patterns from which the screws are cast, the deficiency in
the pitch being made up for by causing the screwed guide plate, which in the
machine formerly patented by the said James Warren is kept at a stated
distance from the bottom plate, to approach the latter. In order to accom-
plish this, we make use of four screws which we call regulating screws.
These screws are driven simultaneously with the guide screws by any suitable
means. They are shewn in the Drawing with cranks attached, but in
practice either cranks or wheels may be used. The lower portion of each
regulating screw projects through the screwed guide plate, and is cut with a
screw of the pitch requisite to make up the difference between the pitches of
the guide screws and the pattern screws. It works through a nut made fast
to the lower plate, and therefore every turn of these screws diminishes the
distance between the screwed guide plate and the bottom plate the exact
distance necessary to compensate for the difference between the pitch of the
guide screws and the patterns. The regulating screws and their nuts being
moveable, pattern screws of different pitches of thread may be used in the
same machine. These arrangements are more clearly shewn by the Drawings
to be hereafter referred to. The heads of the screws are moulded by means
of a head plate, shewn on the Drawings with splays formed thereon.
The nicks are formed in the following manner:-An iron plate is drilled
with holes of a conical form at proper distances to correspond with the patterns
in the machine. These holes are made a little larger than the heads of the
screws about to be cast, the narrower end being at the surface in contact with
the face of the sand box. In each of these holes a plug is formed by
ramming firebrick earth, mixed in proper proportions with ground brick, on

page_text: cach side of a piece of steel which projects beyond the surface of the plate
sufficiently far to mould the nicks of the screws. These plugs, therefore,
form a fireclay surface for the melted metal to flow against. By the use of
this plate the necessity of using two moulding boxes is obviated. After the
screws are cast, we smooth the countersinks and shanks of the screws by
forcing them into a hard steel die by means of a fly or screw press, the bolt of
which has a hammer face of hard steel, the screw having been previously
annealed when of malleable cast iron. The heads are ground and brightened
by placing the screw to be operated on in contact with the surfaces of two
rollers revolving in opposite directions, having their axes parallel to one
another, and at such a distance apart as to allow of the cast screw being
placed between the rollers. The screw is placed and retained in this position
by the means shewn on the Drawings, and being kept in rapid rotation by the
rollers with which it is in contact, the head is subjected to the action of the
grinder or polisher. The grinder or revolving bob is mounted on a spindlo
driven by suitable means, and at the same time that it revolves on its axis a
rapid endlong or pumping motion is given to it by any one of the well-known
ordinary methods by which means every part of the circumference is brought
in contact with the screw head. In the case of hemispherical headed screws,.
this pumping motion will not be needed. The several parts of the machine
for forming the screw moulds herein described are separately old, and with the
exception of the mode of using the screws a, a, have been combined and
patented by the said James Warren; and the making the screwed guide
plate to descend by means of regulating screws, so as to compensate for the
difference between the pitch of the threads of the patterns and the guide
screws, is new and an improvement on the method heretofore used. The
method of forming the moulds for the heads is also old. The method used
for smoothing the shanks and countersinks of the screws has been before
applied to other purposes, but the adaptation and application to the manufac-
ture of cast screws are new. The several parts of the machine for brightening
and grinding the heads of the screws have also been in use for other purposes
before, but the adaptation and application to the manufacture of cast screws
are new. The peculiarity in the improved screw key or wrench is the
arrangement by which its strength to resist the expansion of the jaws
when turning round a screw or nut is rendered independent of the accuracy
of the fitting of the sliding jaw upon the other or stationary jaw. The
upper jaw rests upon, but is quite detached from a compression bar which
slides up and down on the stem of the lower jaw by means of a milled nut
acting on the thread of a screw cut in the stem of the lower jaw. To the

page_text: upper jaw the cheeks of the tension bar are attached by a pin or stirrup
passing over, or in any manner by which a certain play can be obtained.
This tension bar is bent at right angles to its lower end, so as to allow the
lower screwed end of the stem of the lower jaw to pass through it, in order
that any force employed to force open the jaws of the screw wrench, which
would tend to raise this bar by making it slide on the stem of the lower
jaw, may be borne by the nut; in like manner any force, tending to make the
compression bar descend, would be also borne by the nut. By this arrange-
ment the force applied during the application of the instrument to turn round
a screw nut is from the circumstance of the upper jaw being free to turn on
its centre pin, converted into direct tension on the tension bar and direct
compression on the compression bar. If thought desirable, these two bars
may be made in one piece. The jaws and screw, and other parts of this
instrument, having been in familiar use, are not claimed as our Invention, but.
the construction of screw keys in such a manner as that the force applied to
force open the jaws shall be converted into direct pressure and tension by
making one of the jaws to turn upon a pin or stirrup is new, and a great
improvement on the ordinary modes of construction. The form may be varied
provided this principle is kept in view.
Our improved mode of constructing bridges and flooring is, by forming them
of surface plates of metal, wood, or other material, which may be grooved or
tongued together at their edges, and be of any suitable form, having supports
attached to the under sides tied together by iron rods. Another method is, by
making the flooring or bridge of wrought-iron plates of a square form, bent
at right angles across the diagonal. Two of these plates are then bolted
together, and the triangular piece hanging down is connected to similar pairs of
plates by iron tension rods. By the use of this flooring girders may be
dispensed with, and where metal only is used a fireproof construction is
obtained at a moderate cost.
DESCRIPTION OF DRAWINGS.
Figure 1 is a view of the screw-moulding machine, having the improve-
ments applied thereto. b, c, b, c, are the ordinary cranked guide screws with
the patterns d, d, attached. a, a, are two of the four regulating screws
working in the nuts f, f, and driven, as shewn on the Drawing, by a cranked
axle, similar to those of the guide screws to which it is attached.
3, s, is the
screwed guide plate, which by the action of the regulating screws a, a, is
made to approach the lower plate e, e, at a rate exactly compensating for the

page_text: heads of the screws.
patterns. Figure 2 is a section; Figure 3, a plan of the plate used instead
of the top box to produce the nicks in the heads of the screws. a, a, is a
cast-iron plate with conical holes drilled or cast therein. c, c, are the plugs of
fireclay rammed round steel plates, by which the nicks are formed. b, b, is
an upper plate screwed on to the lower plate to keep the plugs in their places.
Figure 4 is a plan; Figure 5 is a side view of the head moulding and
spraying plate. a, a, is the plate. b, b, are the spray moulds. d, d, are the
head moulds. Figure 6 is a view of the machine used to smooth the shanks
and countersinks of the screws. a is the bolt of a fly press, having a hard
steel hammer face g attached. e is a die formed of hard steel, into which the
screw is forced at f, by the action of the bolt a, on the return of which the
screw is forced out by the pin c, which is attached to the bolt by means of the
cross bar 6 and the links h, h. Figure 7 is a side view; Figure 8, a front
view; and Figure 9, a plan of the machine used to brighten and grind the
a, a, are two rollers revolving in opposite directions, the
upper roller having proper gearing to move it so as to increase or diminish
the distance between it and the lower roller. e, c, is a plate moving on the
table by means of the handle d. A space is left in this plate to admit of a
screw lying on the table by the action of the handle d. The screw is then
brought between the rollers a, a, and, being in close surface contact with of
them, it is thus caused to revolve rapidly while the grinder or polisher b, made
steel, grindstone, emery, bob, or other suitable material, is brought in contact
with it until the head is ground and polished sufficiently. Figures 10 and 11
are two views of the improved screw wrench or key. a, a, is the lower jaw,
the shank of which at its lower extremity has a screw thread cut on it. e, e,
is the upper jaw attached to the tension bar 9 by means of the pin p, the
other end resting on the end of the compression bar c, c, by means of the
screw d, which is received into a hollow in the end of the bar c, c. b is a nut
for altering the distance between the jaws to accommodate various sized screw
nuts. The jaw a, a, is grooved to fit the cheeks of the tension bar g, g. The
screw d is for the purpose of keeping the end of e, c, in close contact with the
jaw e, e, but is not tapped into it, merely resting in a small cavity formed in
its upper end. Figure 12 is a side view; Figure 13, a plan of the improved
flooring or bridge. a, a, are studs or supports of iron attached to the plates
d, d. b, b, are connecting rods which bind the whole system of plates
together. a', a', are supports at the corners instead of or in connection
with those in the centre of the plates d, d, in which case the connecting rods
61, 6, 6, 6, are used. Figure 14 is a plan; Figure 15, a side view of a
inodification of the flooring, &c., formed of wrought-iron plates bent across the