IMPROVED APPARATUS FOR HEATING KNIVES FOR REAPING AND MOWING MACHINES IN ORDER TO THE PARTIAL HARDENING OF SUCH KNIVES
Year: 1870

page_text: LETTERS PATENT to Samuel Osborn and William Henry Fawcett,
both of Sheffield, in the County of York, Steel Manufacturers, for
the Invention of "IMPROVED APPARATUS FOR HEATING KNIVES FOR
REAPING AND MOWING MACHINES IN ORDER TO THE PARTIAL HARDENING OF
SUCH KNIVES."
Sealed the 16th August 1870, and dated the 21st February 1870.
PROVISIONAL SPECIFICATION left by the said Samuel Osborn and
William Henry Fawcett at the Office of the Commissioners of
Patents, with their Petition, on the 21st February 1870.
We, SAMUEL OSBORN and WILLIAM HENRY FAWCETT, both of
Sheffield, in the County of York, Steel Manufacturers, do hereby declare
the nature of the said Invention for "IMPROVED APPARATUS FOR HEATING
KNIVES FOR REAPING AND MOWING MACHINES IN ORDER TO THE PARTIAL HARDENING
OF SUCH KNIVES," to be as follows, that is to say :-
This Invention relates to the partial hardening of knives for reaping
and mowing machines, the object of such partial hardening being to

page_text: combine hard cutting edges with tough middle and back parts, and the
process being effected by partially heating the knives and subsequently
dipping them into a liquid.
The Invention consists in constructing the furnace for heating the
knives and the appliances for holding them in the furnace in an
improved manner as follows:-The improved furnace is a structure
of brickwork by preference enclosed and bound by iron plates and of a
rectangular or other convenient shape in horizontal section. It is fitted
with grate bars for the fuel, with access for air beneath. The fire
chamber above the bars is fitted with a closing door for introducing the
-fuel,-but-is-closed-with-the-exception-of-the-outlet-flue-and-of-a¯narrow-
horizontal slit at the longer side for the introduction of the knives, the
bottom of the slit opening serving as the rest for the appliances in which
the knives are held. Each holding appliance is like a cross in flat side
view and a fork in edge side view. The shank is a long flat bar serving
as a handle. The cross bar is formed with a groove closed at the ends
to receive the back of the knife, and from the middle of the cross bar
portions (corresponding to fork prongs) extend on each side towards the
point of the knife to cover its middle part. When a knife is placed in
the holder only the slant cutting edges are exposed to the heat, so that
only those parts become heated. Each holder may be constructed to
hold one, two, or more knives at a time.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Samuel Osborn and William Henry Fawcett in
the Great Seal Patent Office on the 20th August 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME we, SAMUEL
OSBORN and WILLIAM HENRY FAWCETT, both of Sheffield, in the
County of York, Steel Manufacturers, send greeting.
-
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-first day of February, in the
year of our Lord One thousand eight hundred and seventy, in the
thirty-third year of Her reign, did, for Herself, Her heirs and successors,
give and grant unto us, the said Samuel Osborn and William Henry
2

page_text: Fawcett, Her special licence that we, the said Samuel Osborn and
William Henry Fawcett, our executors, administrators, and assigns, or
such others as we, the said Samuel Osborn and William Henry Fawcett,
our executors, administrators, and assigns, should at any time agree with,
and no others, from time to time and at all times thereafter during the
term therein expressed, should and lawfully might make, use, exercise,
and vend, within the United Kingdom of Great Britain and Ireland, the
Channel Islands, and Isle of Man, an Invention for "IMPROVED APPARATUS
POR HEATING KNIVES FOR REAPING AND MOWING MACHINES IN ORDER TO THE
PARTIAL HARDENING OF SUCH KNIVES," upon the condition (amongst others)
that we, the said Samuel Osborn and William Henry Fawcett, our
executors or administrators, by an instrument in writing under our, or
their, or one of their hands and seals, should particularly describe and
ascertain the nature of the said Invention, and in what manner the same
was to be performed, and cause the same to be filed in the Great Seal
Patent Office within six calendar months next and immediately after
the date of the said Letters Patent.
NOW KNOW YE, that we, the said Samuel Osborn and William
Henry Fawcett, do hereby declare the nature of our said Invention, and
in what manner the same is to be performed, to be particularly described
and ascertained in and by the following statement in writing, reference
being had to the accompanying Drawings, that is to say :—
Our said Invention relates to the partial hardening of knives for
reaping and mowing machines, the object of such partial hardening
being to combine hard cutting edges with tough middle and back parts,
and the process being effected by partially heating the knives and
subsequently dipping them into a liquid.
Our Invention consists in constructing the furnace for heating the
knives and the appliances for holding them in the furnace in an improved
manner.
And in order that the same may be properly understood and carried
into practical effect, we have hereunto appended a Sheet of explanatory
Drawings to be herein-after referred to, and representing our improved
furnace and holders.
Figure 1 is a side elevation of the furnace; Figure 2, an end eleva-
tion; Figure 3, a transverse vertical section; and Figure 4, a horizontal
section.

page_text: Our improved furnace is a structure of brickwork 1, which is by
preference enclosed and bound by iron plates 2, and is of a rectangular or
other convenient shape in horizontal section. It is fitted with grate
bars 3for the fuel, with access for air beneath. The fire chamber 4
above the bars is fitted with a closing door 5 for introducing the fuel,
but is closed with the exception of the outlet flue 6 and of a narrow
horizontal slit 7 at one of the longer sides for the introduction of the
knives, the bottom of the slit opening serving as the rest for the
appliances in which the knives are held.
Figures 5 and 6 are views at right angles to each other of our improved
holding appliance_as_made_to_receive_one_knife_at_a_time,_and_Figure-7
shows the holder as made to receive two knives. It will be observed
that the holder is shaped like a cross in flat side view, Figure 5, whilst
it resembles a fork in edge side view, Figures 6 and 7. The shank 8 is
a long flat bar serving as a handle, and to counterbalance the other end
when the holder is placed in the furnace slit 7, as shown in Figure 4.
The cross bar 9 is formed with a groove closed at the ends, as indicated
by dotted lines, to receive the back of the knife, and from the middles of
the sides of the cross bar 9 portions 10 (corresponding to fork prongs)
extend on each side towards the point of the knife to cover its middle
part. In Figure 4 a number of holders with knives in them are shown
as in position for being heated, and it will be observed that when a knife
is placed in the holder only the slant cutting edges (colored blue) arc
exposed to the fire, so that only those parts become sufficiently heated
for the hardening process, the other parts being covered and protected
by the holders. The holders are by preference made of malleable iron
and each may be constructed to hold one, two, or more knives at a
time.
.
Having thus particularly described our said Invention, and the
manner in which the same is to be performed, we have to state that
we do not restrict ourselves to the precise details herein described or
delineated; but that what we believe to be novel and original, and claim
as the Invention secured to us by the herein-before in part recited Letters
Patent is,―
1. The constructing of furnaces for heating knives for reaping and
mowing machines in the improved manner substantially as herein-before

page_text: And, 2. The applying of holders substantially such as are hercin
described and delineated for obtaining the partial heating and consequent
partial hardening of knives for reaping and mowing machines.
In witness whereof, I, the said William Henry Fawcett, on behalf
of the said Samuel Osborn and myself, have hereunto set my hand
and scal, this Nineteenth day of August, in the year of our
Lord One thousand eight hundred and seventy.
WILLIAM HENRY FAWCETT. (L.S.)