IMPROVEMENTS IN MACHINERY OR APPARATUS FOR GRINDING OR SHARPENING THE CUTTERS OF REAPING AND MOWING MACHINES
Year: 1868

page_text: LETTERS PATENT to James Hemington, of Chatteris, in the County of
Cambridge, Corn Merchant, for the Invention of "IMPROVEMENTS IN
MACHINERY OR APPARATUS FOR GRINDING OR SHARPENING THE CUTTERS OF
REAPING AND MOWING MACHINES."
Sealed the 15th December 1868, and dated the 18th June 1868.
PROVISIONAL SPECIFICATION left by the said James Hemington
at the Office of the Commissioners of Patents, with his Petition, on
the 18th June 1868.
I, JAMES HEMINGTON, of Chatteris, in the County of Cambridge, Corn
Merchant, do hereby declare the nature of my said Invention for "In-
PROVEMENTS IN MACHINERY OR APPARATUS FOR GRINDING OR SHARPENING THE
CUTTERS OF REAPING AND MOWING MACHINES," to be as follows:--
This Invention has for its object the grinding or sharpening the knives
or cutters of reaping and mowing machines in a more efficient and expe-
ditious manner than heretofore, and consists of a peculia combination
and arrangement of adjustable grinding apparatus for that purpose. A

page_text: circular revolving grinding stone is employed fixed upon a spindle
rotated by a winch handle or otherwise, which spindle is supported in
a frame capable of adjustment to any vertical or horizontal angle, and
of being fixed in its adjusted position by set screws, or other con-
venient contrivance. The object of adjusting the frame to an angle is
to bring or adapt the edge of the grindstone well into the angles of the
particular knife or cutter bar operated upon, thereby causing the stone
to fit the bevel edge of such knife or cutter bar. The knife or cutter
bar is held in a clamp, which is capable of turning on a pivot, so that
the knife after having had one angle sharpened may be turned on
the pivot referred to in order to bring the opposite angle under the stone.
At the completion of the two edges the blade is loosened, and moved
forward within the clamp so as to bring a fresh pair of edges under
the influence of the stone, and so on till the whole has been sharpened.
Provision is made in the adjustable frame by making slots therein for
lowering the spindle so as to compensate for the wear of the stone.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said James Hemington in the Great Seal Patent
Office on the 17th December 1868.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, JAMES
HEMINGTON, of Chatteris, in the County of Cambridge, Corn Merchant,
send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Eighteenth day of June, in the year of
our Lord One thousand eight hundred and sixty-eight, in the thirty-
first year of Her reign, did, for Herself, Her heirs and successors, give
and grant unto me, the said James Hemington, Her special license
that I, the said James Hemington, my executors, administrators, and
assigns, or such others as I, the said James Hemington, 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 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 MACHINERY OR
APPARATUS FOR GRINDING OR SHARPENING THE CUTTERS OF REAPING AND MOWING

page_text: MACHINES," upon the condition (amongst others) that I, the said James
Hemington, my executors or administrators, by an instrument in writing
under my hand and seal, 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 I, the said James Hemington, 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, reference being had to the accompanying
Drawings, and to the letters and figures marked thereon, that is to
say:-
My said Invention has for its object the grinding or sharpening the
knives or cutters of reaping and mowing machines in a more effecient .
and expeditious manner than heretofore, and consists of a peculiar com-
bination and arrangement of adjustable grinding apparatus for that
purpose. A circular revolving grinding disc of stone, emery, or other
grinding composition is employed fixed upon a spindle rotated by a
winch handle or otherwise, which spindle is supported in a frame capable
of angular adjustment in a vertical plane, and of being fixed in its
adjusted position by set screws, or other convenient contrivance. The
object of adjusting the frame to an angle is to bring or adapt the edge
of the grindstone or disc well into the angles of the particular knife or
cutter bar operated upon, thereby causing the stone or disc to fit the
bevelled edge of such knife or cutter bar. The knife or cutter bar is held
in a clamp, which is capable of turning on a pivot, so that the knife
after having had all the corresponding sides or angles of the teeth
sharpened, may be turned on the pivot referred to in order to bring
the opposite sides or angles under the stone or disc, the angle of the
latter being also reversed to suit the altered position of the knife. At
the completion of each edge the blade is loosened and moved forward
within the clamp so as to bring the next cutting edge under the
influence of the stone or disc, and so on till the whole has been sharp-
ened. Provision is made in the adjustable frame by making slots therein
for lowering the spindle so as to compensate for the wear of the stone
or disc.
And in order that my said Invention may be fully understood I shall

page_text: now proceed more particularly to describe the same, and for that purpose
shall refer to the several Figures on the annexed Sheet of Drawings, the
same letters of reference indicating corresponding parts in all the
Figures.
Figure 1 of my Drawings represents an end elevation of my improved
machine; Figure 2 is a corresponding plan of the same; Figure 3 is an
elevation of the driving side of the machine corresponding to Figure 1;
and Figure 4 is a similar view of the opposite side of the same, shewing
the grindstone or disc.
A represents the upper portion of a wooden or metal frame or standard,
upon which is bolted the cast-iron bracket B, carrying the whole of the
mechanism. In the upright lugs of this bracket there is fitted a square
rocking bar C, which has rounded journals formed at each end, and is
tightened up in its bearings in the lugs by adjusting nuts a, a. Upon
this bar is fitted either directly or through the intervention of the slide D
the upright standard E.
In my Drawings I have shewn the standard E as being secured by a
pinching screw b to the slide D, a slot c being made in the lower part of
the standard through which the screw passes for the purpose of enabling
the standard to be adjusted to any desired elevation, or to be lowered
in proportion as the grinding stone or disc F wears away. d is a pinching
screw, which serves to fix the slide D in any desired position upon the
rocking bar C. The stone or disc F in lieu of being bevelled on the
edges is made parallel, or with its grinding surface at right angles to the
side or face, as shewn clearly in Figure 1. It is secured on to the end of
the spindle G by a nut e, or otherwise, and this spindle turns in bearings
in the lower portion of the standed E. On the back end of the spindle G
there is mounted a spur pinion H, which gears with the large spur driving
wheel I, mounted loosely upon a fixed stud centre in the upper part of
the standard, and provided with a winch handle K for driving the same
by hand. The upper front part of the standard carries a screw f, which
enters a longitudinal slot in the adjustable bracket L, mounted on the
adjusting screw spindle M. By slacking the thumb nut g the screw ƒ
is free to slide along the slotted bracket L, and thus enables the
standard E to be removed to any desired angle from the vertical (shown
by the said lines in Figure 1), and be there fixed by tightening the
thumb nut g. The lower end of the screw spindle M works freely in a
socket h in order to enable it to accomodate itself to any angle of the

page_text: main standard, and it is provided with a small hand wheel N, by which
it is rotated when any nice adjustment of the angle of the stone or disc
is required, the rotation of the screw spindle M tending to raise or lower
the slotted piece or bracket I along the screwed portion of the spindle,
and thereby altering the angle of the main standard. The knife O to be
ground is supported in the machine in a horizontal position by the two
adjustable rests P, P, hinged at i, i, to the carrying frame or table, and
adjustable in height by the swivel pieces k, k; Q is a swivel holder,
shown in full sized longitudinal section and plan at Figures 5 and 6
respectively for receiving the cutter bar. This holder consists of a pair
of swivel jaws 1, 1, mounted upon the slide m, which works along a slot
in the metal bracket B towards and from the stone or disc. A bolt n
passes through the slide m, and through the swivel jaws, and has a
shoulder o formed upon it, against which shoulder the two swivel jaws
are held by the tightening nut p, which at the same time causes them to
grip and hold firmly the cutter bar. As the jaws are free to turn on the
bolt n the cutter bar can be readily turned or adjusted to any horizontal
angle required to suit the angle of the knife edge, the vertical angle of
the stone or disc being adjusted as herein-before described to suit the
bevel of the knife. By moving the slide m along its slot the whole of
the cutting edge from the root to the point will be progressively brought
under the stone or disc during the grinding action.
Having now described and particularly ascertained the nature of my
said Invention, and the manner in which the same is or may be used or
carried into effect, I would observe in conclusion that what I consider
to be novel and original and therefore claim as the Invention secured
to me by the herein-before in part recited Letters Patent is,-
1st. The general combination and arrangement of machinery or appa-
ratus for grinding and sharpening the cutters of reaping and mowing
machines, as herein-before described.
2nd. The application and use to and in the grinding or sharpening of
the cutters of reaping and mowing machines of a parallel edge grinding
disc of stone, emery, or other suitable grinding composition, mounted in
a frame capable of adjustment to suit the bevel of the cutter, substantially
as herein-before described.
3rd. The use of the adjustable frame which carries and adjusts the disc
or stone to the angle or bevel required, as herein-before described.

page_text: 4th. The use of a swivel clamp for holding the cutter bar whilst under
the action of the grinding or sharpening stone or disc, substantially as
herein-before described.
In witness whereof, I, the said James Hemington, have to this
my Specification set my hand and seal, the Fifteenth day of 5
December, One thousand eight hundred and sixty-eight.
JAMES HEMINGTON. (L.S.)