IMPROVEMENTS IN INSTRUMENTS USED FOR CUTTING OPEN TIN CASES OF EVERY DESCRIPTION WILICH CONTAIN PRESERVES OF ANY KINDS, ALSO FOR OPENING TIN OR ZINC CASES USED FOR PACKING OR PRESERVING ARTICLES OF ANY DESCRIPTION."
Year: 1881

page_text: LETTERS PATENT to Henry Knight of Ryde, Isle of Wight, in the County of
Southampton, Importer of Sculptures, for an Invention of IMPROVEMENTS IN
INSTRUMENTS USED FOR CUTTING OPEN TIN CASES OF EVERY DESCRIPTION
WILICH CONTAIN PRESERVES OF ANY KINDS, ALSO FOR OPENING TIN OR
ZINC CASES USED FOR PACKING OR PRESERVING ARTICLES OF ANY
DESCRIPTION."
COMPLETE SPECIFICATION filed by the said Heury Knight at the Office of
the Commissioners of Patents on the 7th May 1881.
HENRY KNIGHT, of Ryde, Isle of Wight, in the County of Southampton,
Importer of Sculptures. IMPROVEMENTS IN INSTRUMENTS USED FOR CUTTING
OPEN TIN CASES OF EVERY DESCRIPTION WHICH CONTAIN PRESERVES OF ANY
KINDS, ALSO TIN OR ZINC CASES USED FOR PACKING OR PRESERVING ARTICLES
OF ANY DESCRIPTION."
MyInvention consists of the improvements herein after described, in constructing
and arranging the parts of instruments, and constructing instruments according to
my Invention which are especially adapted for opening at the edge any tin case
without spilling the contents, and most suitable for opening cases that contain
preserved meats, fish, fruit, vegetables, milk, and other like things or materials,
paints, or any things packed or preserved in tin or zine cases. The said instruments
as ordinarily constructed consist either of a cutter fastened into a lever near the
fulcrum end when the cut is obtained by raising the lever, or the lever and cutter
are formed of one flat piece of metal with a pin for a fulcrum, and in another kind
the cutter is constructed to work through a mortice fúlerum piece, both these
cut by pressing the lever downwards, yet another instrument is constructed with
two levers having a cutter at the end of one lever and a wedge shaped groove at
the end of the other; the levers are pinned together like scissors, and in use have
the same action. In constructing the cutting instruments according to my
Invention I proceed substantially as follows:-I make the fulcrum of an instru-

page_text: .
ment slightly concave, like a gouge, or I make an instrument and fix a grooved
wheel at the fulcrum; I also make an instrument and form a groove at the
fulcrum of the lever, the object in each case being the same, that is, to form a
guide which shall keep the fulcrum of the lever on the edge of the case during the
cutting operation, which will enable the operator to cut the metal close up to the
edge of the case, when either the above guides. is used the instrument is
heeled over outwards by the operator to an angle of about 45, and the instrument
is best worked near this angle during the cutting operation; but if worked near
right angles it does not cut so close to the edge. The cutting is performed by an
upstroke of the lever, the instrument moving forward by the down stroke of the
lever; I also make an instrument with a side guide fixed to the side of the lever at
the fulcrum end; I use this guide to keep the instrument in a line when cutting
open the case at right angles. This guide can be fixed or may be shifted to any
required gauge, enabling the operator to cut open the case at a uniform distance
from the edge. This instrument is worked by the operator holding the handle of
the lever and raising it up and down, cutting by the upstroke, the down stroke
moving the instrument forward. I also make an instrument provided with a side
guide fixed to the side of the lever at the fulcrum end, and a grooved guide formed
at the fulcrum in working this instrument, if the side guide is used, it is heeled
over to about the angle of 45. By the upstroke the cut is effected, the down stroke
sending the instrument forward. I also make an instrument having a loose fulcrum
piece which is grooved and open at one end and attached to the fulcrum of the
lever; the fulcrum end of the lever and the cutter work in the centre groove,
and at the side of the fulcrum piece is a side guide. This instrument works at
right angles, and the cutting is effected by the upstroke of the lever, and at the
down stroke of the lever the instrument moves forward. The cutter with one
edge bevelled cuts the metal clean at one edge and turns up the other edge, and a
cutter with both its edges bevelled cuts in the centre of the groove and turns up
both edges of the metal. I also make an instrument having a square loose fulcrum
piece with a cutting edge formed at right angles and with a side guide. The
cutting blade and the fulcrum of the lever is formed.of.one flat piece of metal, the
cutter bevelled outwardly. The fulcrum of the lever and the fulcrum piece are
pinned together, and by the upstroke action of the lever the cutting blade cuts
against the sharp angle of the fulcrum piece leaving one clean cut edge and turning
up the other, and by the down stroke of the lever the instrument goes forward.
Having described the instruments constructed according to my Invention, which
cut by the upstroke of the lever, I now proceed to describe those instruments
constructed according to my Invention that cut by the down-stroke of the lever.
I make an instrument with a loose fulcrum piece having a cutting edge at right
angles with a side flange for a guide. The fulcrum piece is provided with a hole
near the end and so is the lever cutter, and a fulcrum pin fixes them together,
allowing the parts to work freely. The cutter has one edge bevelled outwards,
which turns up the edge of the metal while the other cuts a clean edge against the
edge of the fulcrum piece. By the down stroke of the lever the cut is effected, and
by the upstroke of the lever the instrument is moved forward..I make an
instrument with a loose fulcrum piece with or without a side flange for a side
guide. The said piece is provided with a hole in the centre, so also is the lever
cutter just above the cutting edge; a fulcrum pin fixes them together, the lever
working freely on the pin. The said fulcrum piece. always keeps the same surface
bearing on the metal and prevents the instrument 'slipping, and makes it safe:
By the down stroke of the lever the cut is effected; and by the up stroke of the
lever the instrument moves forward. I make an instrument with a loose fulcrum
piece grooved through the centre, except a small portion which is left at one end to
keep the metal together: The metal each side of the groove bas a cutting edge
formed at right angles; the lever cutter is made the size of the groove with two
sharp cutting edges formed at right angles and works freely in the groove by the
up and down stroke, the fulcrum pin passing through the loose fulcrum piece and

page_text: through the lever cutter fixes both together in working order. A side flange fixed
to the fulcrum piece is added as a guide to keep the instrument in a straight line.
This instrument will cut a piece of metal clean out the size of the groove, and will
leave two clean cut edges. The groove is made a little wider at the top to allow
the piece of metal cut out to pass off freely. By the down stroke of the lever the
cut is effected, and by the upstroke of the lever the instrument is moved forward.
Having now described the instruments that are worked by a single lever I proceed
to describe those instrunients that are worked by two levers. I make an instrument
having a grooved wheel which I fix to the end of the lever, and the said grooved
wheel has two cutting edges formed at right angles. The inside of the groove is a
little undercut to allow the cut out metal to escape freely, but the groove need not
be undercut when the metal is not cut out. To the end of the other lever I fix a
cutter and both levers are jointed together by the fulcrum pin, and the action of
the instrument is the same as shears or scissors. By pressing together the levers
the cutting is obtained, the cutter being forced into the groove of the wheel, and in
opening the levers the instrument is pressed forward. When I use a cutter having
both edges bevelled the metal is cut in the centre of the groove and leaves both
turned up; if I use a cutler with one edge bevelled it cuts one edge of the metal
clean and turns up the other, and when I use a cutter having two edges formed at
right angles a piece of metal is cut out the width of the groove, leaving two clean
cut edges. In addition to its cutting properties this grooved wheel will act as a
guide in cutting open metal cases at their extreme edge. I now proceed to refer
to the accompanying Drawings, explaining the figures and letters affixed thereto.
A represents a grooved guide at the fulcrum end of the lever. A represents a
side guide formed on the fulcrum piece. ,, represents a grooved wheel; al
represents a side guide at the fulcrum end of the lever; a, a, represents a grooved
wheel; a 1,represents a parallel groove; represents a fulcrum piece which swings
on the fulcrum pin of the cutter: C represents the fulcrum pin; represents the
screw or rivets fixing the cutter in the lever; e represents the cutter; f represents
the start which goes into the lever handle; represents the handles. The manner
in which the instrument. Fig. 3. is used is as follows:-The handle is raised
bringing the instrument to nearly perpendicular position, and then the point of
the cutter is pressed down into the metal case to be opened close to the edge.
The handle is then lowered sufficiently to allow the cutter to pass freely forward
under the metal, the grooved guide on the fulcrum end of the lever being placed
on the extreme edge of the metal case, then the instrument is heeled over to about
the angle of 45, and whilst cutting is kept at about that angle. The cut is
obtained by lifting the handle of the lever, and the cutter is pushed forward under
the metal by lowering the handle. By again raising the handle the second cut is
obtained, and so by lowering and raising the handle this instrument performs its
work easily, cleanly, and safely, the instrument not being able to slip. Figs. 1,
2 H, 23. 26, 27, 30, 31, 34, 35, 38, 39, and 42, are all worked in the same way as
Fig. 3, when the grooved guide or side guide is used. Fig. 2 is an, end view of
Fig. 2 H. Fig. 24 is an end view of Fig. 23. Fig. 27 Shows a straight cutter
pinned at D in the mortice of the lever. Fig. 28 is an end view of the same. The
instrument, Fig. 3, I also make with a side guide at the side of the fulcrum end of
the lever, as shown in the following side views. Fig. 30, letter A, shows a hent
pin side guide fixed witli a set screw having a straight cutter fixed in the mortice
of the lever by two screws d, d. Fig. 29. end view of the same.. Fig. 34. shows a
roller pinned on a projecting piece at the side of the fulcrum to, be used as a side
guide. Fig. 33 is an end view of the same. Fig. 38 shows a screw passing through.
the fulcrum end of the lever, which can be set to any gauge by turning the screw
in or out. This screw has a flat head which forms a side guide... Fig. 37 is an end
view of the same. Fig. 39 represents the side view of an instrument.. is the
grooved wheel fixed in a mortice by the pin C at the fulcrum. end of the lever.
Tig. 40 is an end view of the same. Fig. 42 is a flange formed solid at the
fulcrum end of the lever. These sides guides all project below the lever enough to

page_text: keep the instrument in a straight line when in use. When this instrument with
the side guides is used, it is not heeled over as is the case when the grooved guides
are used, but kept at right angles with the tin case, but it otherwise performs its
work by the same action. Fig. 41 is an end view of Fig. 42. Fig. 3 may be made
with either the grooved guide or the side guide separately, or the same instrument
may possess both guides, as one guide does not interfere with another in working.
Fig. 2 represents an instrument with a grooved fulcrum. piece open at the end to
allow the cutter and fulcrum to work between, pinned or fixed together by pin C.
The lever of this instrument is raised nearly perpendicular, and the point of the
cutter is pushed into the tin, when, the handle is lowered nearly level and pushed
forward under the tin, the fulcrum piece remaining above the metal. By raising
the lever the tin is sheared or cut between the fulcrum piece and the cutter, and by
lowering the hand the cutter is pushed forward. By raising the lever again a
second cut is obtained, and so on until the operation is complete. Fig. 15 is a
modification of the above fulcrum piece (Fig. 2). Fig. 16 is an end view of Fig. 15.
Fig. 13 is an end view of Fig. 14, which is the same as Fig. 2. To the fulcrum
piece I sometimes make a side guide, as shown in Figs. 17 and 18, with a side
flange, as shown in Figs. 21 and 22, with a roller pinned or screwed on to the
flange. Fig. 11 is an instrument with a fulcrum piece fixed on one side with, a
flange guide secured at the fulcrum. The fulcrum piece has a square cutting edge,
by working against which the cutter effects the cut, the cutter being made with a
bevelled edge. The operation is performed in the same manner as Fig. 2. Fig. 12
is an end view of Fig. 11. Fig. 5 represents an instrument with a loose fulcrum
piece grooved in its centre attached to the centre with the pin C. This cutter works
between groove, which is open at one end. The edges of the fulcrum piece are
cut at right angles, so is the cutter, and the width of the cutter is the width of the
groove. The manner in which this instrument performs its work is by the handle
being raised nearly perpendicular, and then the point of this cutter is pushed into
the tin; now the handle is lowered by pressing it down, and this down stroke cuts
the tin the width of the cutter leaving two clean edges. By raising the hand the
instrument is pushed forward, and by pressing it down to the tin it cuts, and so on
until the operation is complete. Fig. 31 shows a fulcrum piece made separately
from the cutter; the dotted line shows the start of the cutter passing through the
mortice of the fulcrum piece at the pin d. Fig. 32 is an end view of the same.
Fig. 19 represents a cutter and fulcrum formed of one thin piece of metal, which
works in the fulcrum piece of Figs. 14, 18, and 22. Fig. 1 is the side view of
an instrument made entirely of one piece of metal. Fig. 4 is an instrument, of
which a, a, is a grooved wheel, the groove in the centre of the wheel being
cut at right angles forming two sharp cutting edges, and is fixed in the
mortice at the end of the lever by the pin C; e is a cutter fixed in the other lever
at. The two levers are pinned together at C: g. g. is the start of the lever
joining the handle, Fig. 4J is an end view of the same. The manner in which
this instrument is used is as follows:-The handles are held and worked during the
operation by one hand. They are first raised nearly perpendicular; the point of
the cutter is forced down into the metal case; the handles are then lowered and
this brings the metal between the cutter and the wheel. By the pressure of the
hand the levers are squeezed together forcing the cutter into the grooved wheel.
By this action the metal is cut. A spring, spiral or otherwise, is fixed between
the levers to open them; if the grooved wheel is used on the edge of the case it
will act as a guide as well as a cutter. This instrument can be used for cutting
in any direction, and the shaped cutter having two cutting edges formed at right
angles will take a piece of the metal clean out the size of the groove, and the cut
metal passes off at the upper part of the groove. If the cutter has one bevelled
edge it will cut one edge of the metal clean and turn the other up, and if both
edges of the cutter are bevelled the metal is cut in the centre of the groove and
leaves both edges turned up. Fig. 4M is a side view of an instrument, and
Fig. 4 L is an end view of the same.. a, a, represents a groove cut at right

page_text: angles in the centre of the end of the lever a, a, 1. This instrument is worked in
the same manner as Fig. 4, except that the groove forms no guide. Fig. 4K
represents an end view of half a circle cut out of the solid metal of the end of
the lever; a groove being cut at right angles leaves two sharp cutting edges. The
form of head is a modification of the wheel, and will also act as a guide. Fig. 8 is
an instrument having a side fulcrum piece with a cutting edge formed at right
angles; the cutter c is formed like a scissors blade and is jointed to the loose
fulcrum piece by the pin C. The action is the same as Fig. 5 except when the
bow G is joined to the loose fulcrum piece, it has then the action of scissors.
Fig. 9 is an instrument with a loose fulcrum piece attached to the cutter by the
pin C; this fulcrum piece prevents the cutter from slipping, and always presents
the same flat bearing on the metal case during the operation; the action is the
same as Fig. 5, but the cutter only splits the tin: Fig. 10 is an end view of the
same: Fig. 7 is an end view of Fig. 8; Fig. 6 is an end view of Fig. 5.
Having now described the nature of my Invention and the manner in which the
same to be performed, I wish it to be understood that I do not limit myself to
the precise details herein described and illustrated in the Drawings, as the same
may be varied without departing from the nature of my Invention, but I claim as
my Invention of improvements in instruments used for cutting open tin cases of
every description which contain preserves of any kinds, also tin or zinc cases used
for packing or preserving articles of any description.-
Firstly. The arrangements or combinations of parts herein-before described and
illustrated in the accompanying Drawings of a grooved wheel guide and a grooved
guide formed at the fulcrum of the lever, a side guide fixed at the fulcrum
end of the side of the lever, a side guide fixed at the side of the loose fulcrum piece,
a fulcrum piece grooved in the centre and opened one end, a solid fulcrum piece
with a cutting edge at right angles, a solid fulcrum piece with no cutting edge,
a grooved wheel with cutting edges at right angles, a half circle formed out of the
solid metal grooved at right angles forming two cutting edges, a cutter having two
cutting edges at right angles, two circular flanges fixed so as to form a groove, a
fulcrum piece with a flange, a fulcrum piece with a roller, a fulcrum piece with a
bent pin, a fulcrum with a screw, flat head, a bent flange attached to the loose
fulcrum piece, a fulcrum piece made separately with a mortice. All the above
named parts are substantially as herein-before described and illustrated in the
accompanying Drawings.
Lastly. A combination of a lever and cutter and loose fulcrum piece, a com-
bination of a lever and cutter and loose fulcrum piece with side guide, a combination
of a lever and cutter with a grooved guide at the fulcrum, a combination of a lever
and cutter with a side guide fixed at the side of the fulcrum end of the lever.
All the above combinations are substantially as herein-before described and
illustrated in the accompanying Drawings.
In witness whereof, I, the said Henry Knight, have hereunto set my hand
and seal, this Seventh day of May, in the year of our Lord One thousand
night hundred and sights ona
Witness,
JOHN MORRANT,
Ryde,
Isle of Wight.
HENRY KNIGHT. (L.S.)