IMPROVEMENTS IN KNIVES AND KNIFE BARS FOR REAPING AND MOWING MACHINES."
Year: 1869

page_text: LETTERS PATENT to Samuel Osborn, of Sheffield, in the County of
York, Steel Manufacturer, for the Invention of "IMPROVEMENTS IN
KNIVES AND KNIFE BARS FOR REAPING AND MOWING MACHINES."
PROVISIONAL SPECIFICATION left by the said Samuel Osborn at the
Office of the Commissioners of Patents, with his Petition, on the
22nd February 1869.
I, SAMUEL OSBORN, of Sheffield, in the County of York, Steel Manu-
facturer, do hereby declare the nature of the said Invention for "Im-
PROVEMENTS IN KNIVES AND KNIFE BARS FOR REAPING AND MOWING MACHINES,"
to be as follows, that is to say:-
This Invention has for its objects to facilitate the fastening, removal,
and renewal of the separate knives attached to the knife bars of reaping
and mowing machines, and to harden the edges of the knives in an
improved manner.
One improvement consists in making the knife bar in the form of
a clip by folding a long strip of malleable iron, steel, or other suitable

page_text: metal along a longitudinal line. The two sides of this folded bar are
set so closely together that the knives, which have their back edges
somewhat sharpened, require considerable force to insert them, whilst
after being inserted they are held with considerable firmness. The
knives may be additionally fixed by rivetting, but it is preferred to
dispense with such fastenings as they give great trouble when a knife
has to be renewed. The two sides of the folded bar may be connected
together at intervals if this is found requisite for maintaining the
gripping power along the entire bar. The knives are by preference
formed without the usual rivet holes, but with one or more holes in
the part which does not enter into the bar for the purpose of inserting
a rod or other tool, by means of which the knife may be entered or
withdrawn without striking the hardened cutting edge. Instead of
folding a single strip of metal to form the bar, two strips may be rivetted
together at a suitable distance apart, and if necessary the inner faces
of the bar or both those faces and the surfaces of the knives may be
corrugated or otherwise roughened to increase the hold.
In another modification the bar may be formed by folding or otherwise,
so as to present a mere rebate to receive the knives, which may then
be fixed with less rivetting than has been hitherto employed.
Another improvement consists in piling the steel knives together in
frames along with alternate iron plates when hardening them. The
interposed plates are shaped so as to leave only as much of the steel
knives projecting as it is wished to harden. Then on heating the pile
the projecting edges of the steel knives attain the necessary temperature
before the other parts, and on applying the hardening process only those
projecting parts become affected.

page_text: WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Twenty-second day of February, in the
year of our Lord One thousand eight hundred and sixty-nine, in the
thirty-second year of Her reign, did, for Herself, Her heirs and succes-
sors, give and grant unto me, the said Samuel Osborn, Her special
licence that I, the said Samuel Osborn, my executors, administrators,
and assigns, or such others, as I, the said Samuel Osborn, my 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 "IMPROVEMENTS IN
KNIVES AND KNIFE BARS FOR REAPING AND MOWING MACHINES," upon the
condition (amongst others) that I, the said Samuel Osborn, my exc-
cutors or administrators, by an instrument in writing under my, 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
Scal Patent Office within six calendar months next and immediately
after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Samuel Osborn, do hereby declare
the nature of my 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 accom-
panying Drawings, that is to say :-
My said Invention has for its objects to facilitate the fastening,
removal, and renewal of the separate knives attached to the knife bais
of reaping and mowing machines, and to harden the edges of the knives
in an improved manner.
And in order that my said Invention and the manner of performing
the same may be properly understood I have hereunto appended a
Sheet of explanatory Drawings to be herein-after referred to, and repre-
senting examples of my improved arrangements.
An example of one of my improvements is shown in plan in Figure 1,
Figure 2 being a corresponding transverse section.
This improvement consists in making the knife bar 1 in the form

page_text: of a clip by folding a long strip of malleable iron or steel, or other
suitable metal, along a longitudinal line. In Figure 2 the strip is shown
as having been folded along its longitudinal centre line; but if preferred
it may be folded along a line more or less on one side of the centre
line, so that one edge may project beyond the other. The folding of
the strip of metal may be effected in any convenient manner, but I
prefer to first bend or partially fold it between a pair of dies in a suitable
press, the upper die being a narrow angular piece which bears upon
the longitudinal centre line of the strip or bar, whilst the lower die
is in the form of a groove with inclined sides. The strip or bar being
suitably heated is laid upon the grooved dic, and is forced and bent
down into the groove by the descent of the upper die. The partially
folded strip is then reheated, and is placed between a pair of flat-faced
dies which compress the two edges of the strip together. The faces
of these second dies are slightly inclined towards each other, and
they compress the edges of the strip together whilst leaving the inner
parts of the recess or groove at a distance apart corresponding to the
thickness of knife to be inserted. The two sides of this folded strip
or bar 1 being set thus closely together at their edges, the knives 2,
which have their back edges somewhat sharpened or bevilled, require
considerable force to insert them, whilst after being inserted they are
held by the spring gripping action of the sides of the folded bar with
such firmness as to resist their removal by even rough usage of the
machine. The knives 2 may be additionally fixed by rivets, but such
fastenings are really unnecessary, and I prefer to dispense with them,
as they give great trouble when a knife has to be renewed. The two
sides of the folded bar 1 may be connected together at intervals, say,
for example, at every three knives, if this is found requisite for main-
taining the gripping power along the entire bar. The knives 2 are
by preference formed without the usual rivet holes, but each with
one or more holes 3 in the part which does not enter into the bar 1
for the purpose of inserting a rod or other tool, by means of which
each knife may be entered or withdrawn without striking the hardened
cutting edge. Instead of folding a single strip of metal to form the
bar 1 two strips may be rivetted together at a suitable distance apart;
and if necessary the inner faces of the bar, or both those faces and the
surfaces of the knives, may be corrugated or otherwise roughened to
increase the hold.

page_text: In another modification shown in plan in Figure 3, and in transverse
section in Figure 4, the bar 1 may be formed by folding or otherwise
so as to present a mere rebate to receive the knives 2, which may then
be fixed with less rivetting than has been hitherto employed. Thus, a
single rivet 4 is sufficient for each knife 2, as the knife is kept steady
and firm in consequence of having its back edge close against the
rib 5 which runs along the back of the bar 1.
My improvement in connection with the hardening of the cutting
edges of the knives 2 consists in piling or arranging them together in
a frame along with alternate plates of iron or other suitable metal or
material. Figure 5 is a transverse section of the frame 6, and shows
one of the interposed plates or "dividers" 7 as in front of a knife 2.
Figure 6 is a section as at right angles to Figure 5, and shows the
knives 2 and dividers 7 in edge view. The dividers 7 and the frame 6
serve to protect from the maximum heat those parts of the knives
which it is wished to avoid hardening; and the dividers are shaped
accordingly, it being kept in view in shaping them that the hardening
extends in practice a little further in than the edges of the dividers.
The frame with the knives and dividers in it is heated, but only until
the projecting edges of the knives 2 are observed to have reached the
proper temperature, and the mass is then removed from the furnace
before the heat extends, and is dipped in water or oil as ordinarily
practised for hardening. By these means the hardening is confined
to the cutting edges, and the body of the knife is thus kept malleable
and tough, and not liable to give way from brittleness.
Having thus particularly described my said Invention, and the manner
in which the same is to be performed, I have to state that I do not
restrict myself to the precise details herein described or delineated; but
that what I believe to be novel and original, and claim as the Invention
secured to me by the herein-before in part recited Letters Patent is,―
1. The making of the knife bar of a reaping or mowing machine
in the form of a clip, substantially as herein-before described.
2. The adapting of the knives to be held, and the holding of them
in a "clip" knife bar, substantially as herein-before described.
3. The forming of knife bars and the fixing of the knives thereon
in the manner herein-before described with reference to Figures 3 and 4
of the Drawings, or substantially so.

page_text: 4. The limiting of the heating action employed for the purpose of
hardening knives for reaping or mowing machines by means of inter-
posed plates or dividers, substantially as herein-before described.
In witness whereof, I, the said Samuel Osborn, have hereunto set
my hand and seal, this Eighteenth day of August, in the year of
our Lord One thousand eight hundred and sixty-nine.
Witness,
EDMUND HUNT,
Patent Agent,
Glasgow.
SAMUEL OSBORN. (L.S.)