Improvements in Knives or Cutters for Opening Sealed Cans or Tins.
Year: 1890

page_text: COMPLETE SPECIFICATION.
Improvements in Knives or Cutters for Opening Sealed Cans or Tins.
I, JOHN SENDALL of Chidham Emsworth Hants. Gentleman do hereby declare the
nature of this invention and in what manner the same is to be performed, to be
particularly described and ascertained in and by the following statement :-
The object of my invention is to construct a knife or cutter for opening hermetically
sealed tin cans and all similar vessels such as are now used for containing preserved
meats & other British & foreign products.
For the purpose of my invention I manufacture my knives or cutters in the following
manner. As a foundation for the blade or cutter I construct a solid metal boss which
may be of any suitable metal, but preferably of cast iron, this metal boss may be of
any length, size or thickness most suitable for the required purpose. On one side of
this boss or foundation I form a recess of the depth & length required, to receive a
small metal wheel. The knife or cutter I make of steel or other metal of sufficient
hardness bending it about midway in its length at an angle of some 40° or thereabouts
as most applicable to the purpose for which it is required, this bent part forms the
cutting portion & is sharpened on one of its edges and also at the point, and may
be made of any length, breadth or thickness required. In the before mentioned recess
in the metal boss, place a solid wheel or pulley of suitable dimensions, which may
be made of metal or any other hard material, the periphery of this wheel I make of a
hollow or concave form. The knife or cutter & also the metal boss being drilled with
two or more holes, as most convenient for the purpose, are then securely fastened
together by means of screws, rivets, or any other suitable method, the before mentioned
wheel being placed in the recess formed for it, between the boss & the knife or cutter
where it is free to revolve when required. The whole is then firmly fixed into a
wooden or metal handle, which handle may be shaped as most convenient to the hand.
The action of my can opener is as follows. On pressure being applied by means of
the handle, the sharp point of the knife or cutter pierces the side of the can or other
vessel to be opened and the cutter passes through the opening thus made until the
concave circumference of the wheel rests on the edge of the can, by continuing the
pressure in a forward direction & also giving an up & down or reciprocating motion
to the handle, the cutter passes round the side of the can, while the wheel runs round
the upper edge, guiding its action & greatly facilitating the operation.
In the accompanying drawings Fig. 1 represents a complete elevation, & Fig. 2 a
plan of my invention in which A is the solid metal boss or foundation, B the concave
wheel which revolves freely on the bolt or spindle D¹ forming the fulcrum on which
the loverage is obtained, C is the knife or cutter with its cutting surface upwards,
D & D are. the screws or bolts securing the whole together, & E is the handle.
Having now particularly described & ascertained the nature of my invention & in
what manner the same is to be performned I declare that what I claim is,
The use of a concave wheel in connection with a cutting blade for opening sealed
cans or similar articles as herein substantially set forth, illustrated and described.
Dated this 9th day of August 1890.
GRAHAM & GRAHAM,
Agents for Applicant.