IN MACHINES FOR CUTTING GRASS, CEREAL, OR OTHER CROPS
Year: 1881

page_text: PROVISIONAL SPECIFICATION left by Henry Hinxman Duke at the Office
of the Commissioners of Patents on the 1st June 1881.
HENRY HINXMAN DUKE, of Westbury, in the County of Wilts.
IN MACHINES FOR CUTTING GRASS, CEREAL, OR OTHER CROPS."
"IMPROVEMENTS
This Invention has for object improvements in mowing and reaping machines,
whereby they are not only improved as regards efficiency of action, but are also
rendered applicable for cutting all descriptions of crops, and relates more especially
to reaping and mowing machines having their knives attached to or formed into
an endless chain, which knives when working pass continuously in one direction
instead of having a reciprocating motion.
The first part of my Invention relates more especially to the construction of the
knife chain, and the second part to the machines generally. In the construction
of the knife chains I employ a sufficient number of pieces of steel, phosphor, bronze,
or other suitable material, preferably oblong in shape. In or near the centre at
each end I form an annular cavity, half in one link or portion and half in the
adjoining one. Within the cavity so formed I place a steel ring. A portion of
each link being cut away from the centre of the ring backwards a joint is formed,
which admits of the chain being carried round a pulley, but prevents flexure in an
opposite direction. In order to prevent the rings falling out, a cover formed of
thin metal is fixed over them, or the knives themselves are so formed as to secure
them in place. The knives, which are the same length as each link, are attached
to them by screws or rivets in such a position as to leave the cutting portion
projecting sufficiently beyond their outside edge. The sides of the knives where
they come in contact when in line I preferably form with a slope backwards from
the direction of their movement. The cutting edges of the knives I preferably
form so that the whole shall be in one straight line when in action, but for some
kinds of crops I prefer making the cutting edges in the form of quadrants of a
circle.
In carrying out the second part of my Invention I employ an endless knife-
chain constructed as previously described, herein supported in a horizontal position
by means of two or moro pullies or discs, round the edges of which it is caused to
travel. These pullies or discs are either circular or many sided, in some cases
Price Od11

page_text: having in addition teeth or projections which fit into corresponding recesses formed
in the back of each link of the knife-chain for their reception. The pullies together
with the knife-chain I place within a metal casing formed either of two plates, or
of one bent into a L shape. When two plates are employed I form the upper one
of such dimension and form as to protect the return portion of the knife-chain,
whilst the knives in the cutting portion project beyond it, the lower plate also
protecting and covering the return portion of the knife-chain, but at the front
being formed into a species of comb, the ends of which are turned over for the
purpose of catching up stones or sticks and lifting them over the knives working
underneath, the return portion being on a level or nearly so with the surface of the
upper plate. In cases in which the casing is formed of one plate, the apex of the
V is formed into a comb. I sometimes find it advantageous to deflect the teeth
of the comb either in whole or in part diagonally to the motion of the machine.
In suitable positions upon the upper plate proper bearings are fixed for carrying
the axles of the discs or pullies, the lower end of the axles being supported by
bearings affixed to the lower plate or plates. One or more of these axles are
carried upwards through the bearing, and have affixed toothed or grooved wheels,
to which motion is communicated either by toothed wheels connected to the
driving wheel, or by means of a grooved wheel and endless band or cord of wire,
gut, or other suitable material, likewise actuated by the driving or carrying wheels
of the machine.
In applying my Invention to lawn mowers and other similar purposes, it is
necessary that the cutting portion should be maintained at a constant level slightly
above the surface of the ground, and this I effect in one of the following ways:-
I form two or more slots in the lower plate, in which I place vertically a ring
of metal, flat outside, but V shaped within; a small shaft is passed through this
ring, which has either a groove turned in it or a pulley revolving upon it which
fils the form of the inside of the ring within which it rolls, and thus supports the
whole with but little friction. The ring is kept upright and prevented from
falling on lifting the machine by a suitable groove or a pin or pins. In another
arrangement I form an opening or openings along the lower plate, and in these I
fix a roller or rollers by bearings capable of vertical adjustment, thus allowing the
cutting portion to be raised or lowered. Above the surface of the upper plate I
sometimes fix a revolving brush, which delivers the cut grass into a receptaclo
suitably placed to receive it; moreover, I occasionally find it advantageous to place
revolving or fixed brushes at the ends of the cutting arrangement in order to clear
the knives of loose particles.
The knives when straight are sharpened whilst the machine is in action by
means of two laps of stone or of emery composition, which are attached to a species
of pincers, and can be brought into action at pleasure by means of a cord actuated
by the driver. I sometimes prefer to use steel discs with plain or serrated edges
for this purpose in place of the stone or emery composition.
In the larger class of machines I preferably arrango the cutting portion so that
it may cut central with respect to the tractive or propulsive power, or to one side
or the other interchangeably.