IMPROVEMENT IN THE METHOD OF FORMING OR PREPARING STEEL FOR THE MANUFACTURE OF SPRINGS FOR CARRIAGES, BUT PRINCIPALLY APPLICABLE TO ALL THOSE USUALLY DENOMINATED COACH SPRINGS
Year: 1822

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JOHN
THOMPSON, of Regent Street, Westminster, and of the London Steelworks,
Thames Bank, Chelsea, send greeting.
WHEREAS His present most Excellent Majesty King George the Fourth
did, by His Royal Letters Patent under the Great Seal of the United
Kingdom of Great Britain and Ireland, bearing date at Westminster, the
Second day of March, in the third year of His reign, give and grant unto
me, the said John Thompson, my executors, administrators, and assigns, His
especial licence, full power, sole privilege and authority, that I, the said
John Thompson, my executors, administrators, and assigns, during the term
of years therein expressed, should and lawfully might make, use, exercise,
and vend my "IMPROVEMENT IN THE METHOD OF FORMING OR PREPARING STEEL
FOR THE MANUFACTURE OF SPRINGS FOR CARRIAGES, BUT PRINCIPALLY APPLICABLE TO
ALL THOSE USUALLY DENOMINATED COACH SPRINGS," within England, Wales, and
the Town of Berwick-upon-Tweed, in such manner as to me, the said John
Thompson, my executors, administrators, and assigns, should in our discretion
seem meet; in which said Letters Patent is contained a proviso that if I,
the said John Thompson, should not particularly describe and ascertain the
nature of my said Invention, and in what manner the same is to be per-
formed, by an instrument in writing under my hand and seal, and cause the
same to be inrolled in His Majesty's High Court of Chancery within two
calendar months next and immediately after the date of the said Letters
Patent, that then the said Letters Patent, and all liberties and advantages
whatsoever thereby granted, should utterly cease, determine, and become void,

page_text: as in and by the said recited Letters Patent, relation being thereunto had,
may more fully and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Thompson, do hereby declare that the nature of my said Invention, and
in what manner the same is to be performed, are particularly described and
ascertained in the Drawing hereunto annexed, and the following description
thereof, and references thereto (that is to say):-
My said Invention consists of an improved method of rolling and preparing
steel for the manufacture of carriage springs, but more especially for coach
springs, by which method not only a considerable portion of labor is saved, but
the quality of the steel is much improved, thereby producing a better and
cheaper spring than has hitherto been made. Notwithstanding the great
variety of form in which carriage and coach springs have been made to
assume, yet their component parts have been generally composed of bars or
plates of the shape of a wedge (or double wedge) in thickness. The steel
prepared for the springmakers have almost generally been parallel bars, both
in width and thickness, and have been invariably brought into their proper
shape and form by the agency of the hammer. This operation has been
attended with considerable labor, expense, and uncertainty, which my method
completely obviates and removes. Therefore, instead of preparing and
forming bars of steel by the hammer into the form of a wedge in its thick-
ness, I produce this formation of bar to any required dimensions with facility
and intirely by my new method of rolling, which I shall hereafter describe.
Fig. 1 represents a view of a set of my pointing rollers, and which rollers
must be made with any convenient number of flat places on their exterior
surface. The flat parts of each roller must be placed opposite to each other;
the curved or compressing parts of these rollers must also stand opposite to
each other. The object to be produced by these rollers is to reduce the point
of the bars of steel to be used for springs that they may be readily introduced
between the tapering rollers, and which is effected by the curved or com-
pressing parts of the rollers, in their peripheral line, being not more than two
inches in length, the point of the bar being thus reduced in its thickness,
and one of each of the flat parts of the rollers being placed opposite to each
other. The bar of steel is thus enabled to be withdrawn from the rollers
after it has been reduced in thickness.
Fig. 2 exhibits a set of tapering rollers, which rollers must be formed of
such capacity of circumference as shall be not only equal to the length of any
required bar that is to be tapered for any spring, but also of a flat or dormant
part of roller as to pressure, which will allow the bar to be withdrawn or

page_text: discharged from between the rollers, as may be found necessary when any bar
or plate is tapered sufficiently long. C, C, is a collar with any convenient
number of grooves suited to the dimensions of the bars or plates, both in
width and thickness, that may be required to be made for any particular.
carriage spring. B, B, are the necks of the rollers; A, A, is a plain cylin-
drical roller; D, D, the standards for carrying the rollers; E, E, are the
pushing or binding screws for keeping or pressing the rollers together to
regulate the thickness of any taper, bar, or plate, but not the proportion of
the taper in substance nor in length. These are determined intirely by the
character and extent of the dimensions of the grooves in the roller C, C.
F, F, are the cog wheels which communicate the motion given to the
roller C, C, to the upper roller A, A; G is the coupling box which connects
the roller C, C, to the first moving power. This grooved roller may either be
placed above or below a plain cylindrical roller with cog wheels to put these
rollers in motion from any first power, or by two grooved rollers as shewn in
Fig. 3.
With either pair of rollers thus formed as Figs. 2 and 3, and put
into a proper frame, I then introduce them one of my pointed bars or plates
in the required groove, and at that part of the groove which is most distant
from the centre of the roller, or at the flat part of the roller. The rollers
in their motion will, by this eccentric or unequal groove in depth, form a bar
or plate varying in thickness, but suited to the eccentricity of the groove by
forming it taper or wedge-like. The bars or plates for springs must be rolled
red hot, after the manner in which ordinary steel bars are generally rolled;
yet I find it highly beneficial afterwards to roll my bars or plates when cold,
by which they are hardened, and the surface made smoother by disengaging
what workmen call the scales on the surface.
My Invention and improved method also extends to the use of plain rollers,
the extreme surface of which are eccentric to their pivots or necks, only
observing that the parts of each roller which is most distant from its centre
must be placed immediately opposite each other, and that the rollers be made
of equal diameters, and that the rotation of these rollers must be so directed
as to make their surfaces recede equally from each other when they start from
the nearest point of contact or approximation till they arrive at the greatest
distance from each other. It is obvious that this disposition of the rollers will
necessarily roll the bars or plates of steel of a taper or wedge-like form, and
which forming of taper, wedge, or double-wedge bars of steel for carriage or
coach springs by the means of rollers constitutes my Invention. The using of
these rollers will require considerable care and dexterity in the workman to
introduce the steel between them at such parts of the rollers as will come

page_text: nearest together. Any workman conversant with rolling of iron or steel will
soon obtain expertness in the rolling of taper bars by the use of the rollers
described; and it will readily appear to him that, by bringing the rollers
closer together, that he will be enabled to take what nip he pleases on any
bar, and can pass it as frequently through any one groove, or as many separate
grooves or plain rollers, as he pleases, or as now is usually done with ordinary
bar or plate rollers. I am enabled by my plan of rolling taper plates or bars
to form my grooves in such a manner as shall not only taper any particular
part of any bar or plates, leaving the rest of the bar perfectly parallel, or I
can taper the bar or plate from the middle to each end, or I can leave any
part of the middle parallel as occasion may require.
My Invention does not consist in any of the abstract or united and com-
bined parts of the machinery described, but in applying such machinery to
effect the fabrication of taper bars, wedge or double-wedge plates of steel for
the formation of carriage or coach springs by means of rollers instead of
hammers.
In witness whereof, I, the said John Thompson, have hereunto set my
hand and seal, this Second day of May, in the year of our Lord One
thousand eight hundred and twenty-two.