AN IMPROVEMENT OR IMPROVEMENTS IN THE MAKING OR MANU- FACTURING OF AXLETREES
Year: 1833

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, CHARLES
COLLINGE, of Number Twenty-two, Bridge Road, Lambeth, in the County of
Surrey, Engineer, send greeting.
WHEREAS His present Majesty King William the Fourth, by His Letters
Patent under the Great Seal of the United Kingdom of Great Britain and
Ireland, bearing date at Westminster, the Second day of May now last past,
did give and grant unto me, the said Charles Collinge, His especial licence,
full power, sole privilege and authority, that I, the said Charles Collinge, my
éxecutors, administrators, and assigns, and such others as I, the said Charles
Collinge, my executors, administrators, or assigns, should at any time agree
with, and no others, from time to time and at all times thereafter 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, my
Invention of "AN IMPROVEMENT OR IMPROVEMENTS IN THE MAKING OR MANU-
FACTURING OF AXLETREES;" in which said Letters Patent there is contained a
proviso, obliging me, the said Charles Collinge, by an instrument in writing
under my hand and seal, particularly to describe and ascertain the nature of
my said Invention, and in what manner the same is to be performed, and
to cause the same to be inrolled in His said Majesty's High Court of
Chancery within six calendar months next and immediately after the date of
the said recited Letters Patent, as in and by the same, reference being there-
unto had, will more fully appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
Charles Collinge, do hereby declare that: the nature of my said Invention, and
the manner in which the same is to be performed, is described and ascertained
by the Drawing hereunto annexed, and as follows, that is to say :-
In manufacturing cast-iron boxes for axletrees of that kind or description
for which my father, Mr. John Collinge, of Lambeth, some years since
obtained a Patent, and also for mail axletrees, great loss has at all times been
sustained by their cracking when they were heated red hot and plunged into
water to produce great. hardness on the inside surface. This evil, it is well
known, arises partly from the peculiar shape or form of the box, and also from
the peculiar quality of the metal itself, which being cast, and consequently
christallized in cooling, is unfit for such a process. In the annexed Drawing,
Fig. 1 represents a vertical section of an axletree of the kind above referred
to, having a hardened cast-iron box. a, a, a, a, represent a section of a cylin-
drical portion, called the body or box, within which may be seen the arm A,
which is likewise hardened, and very accurately fitted by being first truly
turned and then ground; b, b, shews the head of the box, forming, as may be
seen, one entire piece with the body, and containing a cavity or reservoir to
hold oil, which lubricates the arm A, and also the internal surface of the box
a, a, a, a. It is the unequal dimensions of the head b, b, and the body or
box a, a, a, a, as well as the peculiar quality of the metal, that causes them to
crack when submitted to the process of hardening. If this axletree be care-
fully examined it will be evident that the only part of the box that requires to
be hardened is that contained between the letters a, a, a, a, it being the only
part that is submitted to any considerable wear; but as it is found absolutely
requisite to immerse the whole box in water when it is to be hardened, there
does not appear to be a possibility of avoiding the evil before described, namely,
that of their frequently cracking in the process of hardening.
I shall now explain my improved method of constructing and combining
the parts of the boxes of such axletrees, in which my Invention consists, and
by means of which I completely avoid the evil arising from cracks in the
process of hardening, and also produce much more perfect and harder sur-
faces on the internal parts of the bodies of my boxes than can possibly be
produced when they are constructed of cast iron only, and in one entire piece,
as above described. Fig. 2 represents a plan of one of my improved axletree
boxes complete. a, a, a, a, represents the body, made of wrought iron. Being
a hollow cylinder, it is scrolled and welded in a similar manner to that adopted
in the manufacture of twisted gun barrels, a process known so well to work-
men as to need no further description by me in this place. This wrought-iron

page_text: body is carefully prepared by being truly bored, and in that state the inside or
working surface is submitted to the process of carbonization (technically called
case hardening), and when tempered or hardened by being immersed in
water, it is then finally fitted to the arm or axletree by grinding in the usual
manner. b, b, represents the head of the box, which is formed of cast iron,
and which it is not necessary to submit to the process of hardening, conse-
quently there is not the least chance or liability to the evil of cracking; but
as the method of combining or uniting this head with the body firmly and
immoveably is a subject of the greatest importance, I shall now describe the
method that I adopt and prefer, although the union of the two parts may be
effected by a variety of ways well known to those acquainted with the working
of iron. One end of the wrought-iron body is turned down smaller, as shewn
by the dotted. lines at c, c, d, d, having a flat shoulder at d, d. This will be
more plainly seen in Fig. 3, which represents a vertical section of the same
parts combined. The internal parts of the cast-iron head, and more particu-
larly the projecting portion shewn at. e, e, are submitted to the process of
decarbonization, which renders it very soft, and thereby peculiarly applicable to
effect the purpose now to be described.. In turning down the smaller part of
the body of the box, care should be taken to leave the part near d,:d, rather
smaller than c, c, forming thereby a portion of a very acute cone, and if the
cast-iron head be turned out where it has been decarbonized at f, leaving the
part at frather the smallest, it will be found that if they are united or com-
bined by the process of contraction or shrinking, the reverse position of the
conical parts will completely prevent them from separating. when they are
both cold. In order to unite the two parts in the most perfect manner, the
smallest portion of the hollow conical part of the cast-iron head seen near d
should be of such a diameter as barely to pass over the largest portion of
the conical part of the body at c, c, and when so formed or constructed
the cast-iron head must be heated, so as to make it expand, and then it
must be placed upon the reduced part of the neck, bearing on the shoulder
formed near d, d, and; when cold it will be found to have contracted so
much as to be almost inseparably united, and as secure for all the purposes
required as if the two parts were one entire piece. Before the heated, cast-
iron head is placed upon the turned part of the body of the box it should be set
upright, the lower end being previously stopped tight by a cap or any other
convenient means, and in that state the body must be filled with cold water,
which will keep the inside surface of the body cool, and effectually prevent i
from being softened by the heat contained in the cast-iron head, a precaution
of the utmost importance in this particular manufacture. By decarbonizing the

page_text: portion of the cast-iron head that is to be united to the wrought-iron body,
the metal is rendered so soft and pliant as to be capable of being squeezed by
the contraction of the metal in cooling into the most perfect contact with the
reduced part of the body, and thereby effecting the most perfect union between
the two parts. By thus constructing the body of wrought iron the internal
surface. may be case-hardened and finished in the most perfect manner, and by
uniting thereto a cast-iron bead in the manner and way I have described, every
other requisite will be obtained without the least chance or possibility of loss
from cracking in the process of tempering. It may be necessary to state that
after the head is united to the body, in the way above described, the internal
shoulder of the head and other parts must be turned and finished by the usual
means applied for such purposes. Fig. 4 represents a plan of the cast-iron
head and wrought-iron body separated, in order to shew the form of each part
more clearly. Fig. 5 represents a vertical section of a cast-iron head and a
wrought-iron body, united by screwing the two parts together; there is no
other variation in these Figures if they are compared with the three last
described. These screws may be immoveably fixed by a solution of sal
animoniae being placed between them, which, forming an oxyde of iron, will
swell, so as to cement them, and thereby render them as solid as if they were
formed of one entire piece, or they may, when screwed, be fixed by contraction
produced in the way before described. Where soft and strong cast-iron can
be obtained, it may be used without being decarbonized on the internal parts,
as above described; but in all cases where perfection is required, decarboniza-
tion will be found the most effectual. The principle here adopted, namely,
that of constructing the box in two distinct parts, and uniting them together
in the way I have described, is equally applicable to the boxes used for mail
coaches, and which are usually called mail axletrees, the risk attending the
manufacture of such boxes being equally great with those above described.
And I hereby declare that my Invention consists in constructing the boxes of
axletrees (of the peculiar kinds herein described) of two distinct parts, instead
of casting or forming them of one entire piece only; and also in uniting and
combining them by the peculiar methods herein described, by which means
more perfect boxes for axletrees may be made, and the great loss that has
been experienced in hardening them, when made entirely of cast-iron, will be
completely avoided.
In witness whereof, I, the said Charles Collinge, have hereunto set my
hand and seal, this Eighth day of October, in the year of our Lord
One thousand eight hundred and thirty-three.
(L.S.) CHAS COLLINGE. -*

page_text: AND BE IT REMEMBERED, that on the same Eighth day of October, in
the year above mentioned, the aforesaid Charles Collinge came before our Lord
the King in His Chancery, and acknowledged the Specification aforesaid,
and all and every thing therein contained, in form above written. And also
the Specification aforesaid was stamped according to the tenor of the Statute
in that case made and provided.
Inrolled the Twenty-third day of October, in the year above written.