A Machine for Sharpening or Stropping Razors or like Edged Tools
Year: 1896

page_text: Date of Application, 17th Mar., 1896-Accepted, 25th Mar., 1896
COMPLETE SPECIFICATION.
A Machine for Sharpening or Stropping Razors or like Edged Tools
I DAVID THOMSON, of 15 Great Marlborough Street, London, W., Dental
Surgeon 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 :-
This machine is described in the form specially suitable for stropping razors,
but the same principle may be adopted and applied for sharpening any form of
knife and such like edged tool.
It consists of four parts, viz., (1) a stand with bearings (2) two strops or
sharpening rolls (3) a holder for razor (4) means for revolving the strops.
The accompanying drawings show my invention, Fig. 1 being a plan and Fig. 2
a section through the line a-b in Fig. 1.
The stand A may consist of wood, metal, or other suitable material to which is
attached four bearings B to carry two parallel axles C placed at such a distance
apart and at such a height from the stand as may suit the size of the strops D. D.
hereafter described.
The strops D. D. are mounted one on each of the parallel axles C. C. and
consist of narrow strips of metal, vulcanite or other suitable material, having
attached to their faces the buff, leather, or other sharpening material which is to
come in contact with the razor G. These strops D. D. are attached to the
axles C. C. by means of two pins E on each strop, which fit two split tubes F. on
each axle, and are thus removable in order that different strops with graduating
surfaces may be used on the same machine. The strops D. D. are the full length
of the cutting edge of the razor, and are to be bent spirally on the circumference
of such a sized circle as will ensure them coming in contact with the razor G at the
proper angle to effect the purpose aimed at. But as they are to strike the razor
alternately, they must each cover slightly less than half of the circumference of the
circle before mentioned. The strops D. D. are to be coupled by means of cogged
wheels H. H., endless chain, or such like contrivance so as to cause them to revolve
simultaneously in opposite directions, as shown by the arrows in Fig. 2. In this
way the strops D. D. lying parallel with the razor G, and having it between them
will strop it alternately on each side of its edge with a heel to toe movement.
The holder consists of two parallel rods I. I., placed sufficiently apart to allow
the thin part of the blade of the razor to pass between them, but close enough to
prevent the thickened back of same from passing through, in this way allowing it
to lie loosely between them. These rods I. I. are attached to the top of the
bearings and in such a position to the strops D. D. as will bring the razor edge
into its proper relation with them. To retain the razor in place a light steel (or
other material) spring J. fastened by a pivot K. to the end the rods I. I. next the
toe of the razor when in position, rests on the middle of the razor back.
The means for revolving the strops D. D. may be either a handle L. attached to
one of the cogged wheels H. H.; a cord which on being drawn out and released
rewinds by means of a spring; clockwork; electric motor; or any other known
mechanical method.
In sharpening knives or such like tools for which the holder 1. I. is not suitable,
I replace the holder I. I. by any clamp which, while holding the knife or other
tool firmly in position, will still admit of sufficient lateral movement of the cutting
edge to enable the strops to revolve.

page_text: Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
1. A machine for sharpening or stropping razors or like edged tools, having two
parallel spirally arranged strops or sharpening rolls coupled to revolve in opposite
directions, substantially as hereinbefore described and illustrated by the
accompanying drawings.
2. The construction and arrangement of a machine for sharpening or stropping
razors or like edged tools, having two parallel spirally arranged strops or sharpening
rolls coupled to revolve in opposite directions and a holder or clamp fixed or
mounted above and between the strops or sharpening rolls, substantially as
hereinbefore described and illustrated by the accompanying drawings.
Dated this 16th day of March 1896.
DAVID THOMSON.