An Improved Method of and Apparatus for Simultaneously Grinding, Sharpening, and Dressing or Polishing the Surfaces, whether Symmetrical or Unsymmetrical, of the Blades of Knives, Razors, or other Cutting Instruments.
Year: 1896

page_text: Date of Application, 16th June, 1896-Accepted, 25th July, 1896
COMPLETE SPECIFICATION.
An Improved Method of and Apparatus for Simultaneously Grinding,
Sharpening, and Dressing or Polishing the Surfaces, whether
Symmetrical or Unsymmetrical, of the Blades of Knives, Razors,
or other Cutting Instruments.
I, CARL FRIEDRICH ERN of Wald by Solingen, Germany, Manufacturer, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:
In my invention the opposite surfaces, whether symmetrical or unsymmetrical, of
the blades of knives, razors, and other similar cutting instruments are simultaneously
sharpened, dressed or polished by causing the action of the grinding wheel or dise to
be distributed over almost the whole of the surface being ground at the same time,
thereby preventing the instrument becoming too highly heated, and, as a consequence,
injuriously affected whilst being operated upon.
The grinding is done in the opposite way to that at present in vogue, that is to
say, instead of sharpening the instrument on the periphery of a rotating wheel it is
sharpened between the lateral or end surfaces of two revolving wheels or discs which
are capable of being moved laterally either close to or away from each other. Under
the present system only small portions or strips of the instrument can be operated on
at a time with the result that such strips are subjected to the full action of the
grinding wheel frequently becoming very highly heated and in some cases actually
ignited. Independent of this, under the present system, only relatively symmetrical
surfaces can be sharpened and polished at the same time and unsymmetrical surfaces
cannot be properly done, with the consequence that instruments, such as razor blades
can only be mechanically ground to a slight extent.
The above defects and drawbacks are overcome by grinding, as aforesaid, the
instruments between the end surfaces of two revolving emery wheels whose working
faces may be made so as to appear in section of either the same or different contour
according to the nature of the instrument or part of the instrument on which they are
to operate.
And in order that my said invention may be properly understood I have hereunto
appended three explanatory sheets of drawings which illustrate, by way of example,
the method of grinding razors in accordance with my invention. The drawings also
show the grinding wheels used and the manner of introducing the blades between
them.
Fig. 1 is a section of the grinding wheels and Fig. 14 an end view of one of the
wheels as used for grinding flat ground razor blades.
Fig. 2 is a section of the grinding wheels and Fig. 2ª an end view of one of the
wheels, as used for grinding ordinary hollow ground razor blades.
Fig. 3 is a section and Fig. 3A an end view of the wheels used for grinding the
tangs or tails of razors.
Fig. 4 is a section and Fig. 4 an end view of the wheels used for grinding the
edges of a razor tang and therefore for grinding two unsymmetrical surfaces.
Fig. 5 is a front view and Fig. 6 a side view of the machine.
Fig. 7 is a detail view.
Figs. 8, 9 and 10 are views of blade holders or supports.
Fig. 8 shows a holder for use when sharpening razor blades Fig 9 one for use

page_text: when grinding tang side-surfaces and Fig. 10 one for use when grinding tang or tail
edges.
Referring to the drawings:
-
As clearly shown at Figs. 1 to 4 and in the end views at Figs. 14 to 4^ two side
surfaces are, throughout, sharpened, dressed, or polished, as the case may be, at the
same time, according to the amount of grinding required the wheels d, d, are brought
closer together or moved further apart. The instrument when ground is moved
slightly across or against the direction of rotation of the wheels.
With relatively inclined surfaces, as shown at Figs. 1 and 2, the instrument is
simply introduced between the wheels and moved cross wise to the direction of
rotation of the wheels.
The machine shown at Figs. 5 and 6 has a frame A upon which are mounted two
heavy pedestal hearings a carrying, in guided slides b, the driving shaft c for the
emery wheels d, d, with their bearings e, f. The hand wheel g with the graduated
disc at the rear serves to adjust the grinding wheels d, d, relatively to each other.
The wheels d can be raised and lowered by the wheel h, which, like the wheel g, is
mounted on top of the machine.
The frame À also carries besides the driving and transmitting gear, a sliding
support which is held in guides or slides by means of suitable supports.
This
sliding support carries a blade holder when the machine is used to sharpen,
dress, or polish razor blades. A pipe passed through the hollow shaft c of one
of the emery wheels, supplies water, or the sharpening or polishing substance, at
or near to the axes of rotation of the wheels d' so that the centrifugal force of
the latter can be utilized to uniformly distribute the said water or substance. The
uniform distribution of the sharpening or polishing substance is a matter of great
importance in producing good work.
The sharpening or polishing substance could also be fed from above directly to
the wheels d, d, or to their end surfaces, when the machine is used to grind
articles of such thickness that a clear space is left between the wheels d, d, for
the passage of a feed pipe. It is also obvious, in this case, that in order to utilize
the centrifugal force of the rotating wheels for the distribution of the substance
it is necessary for the outflow from the feed pipe to take place at or near the
axes of rotation of the wheels. An arrangement of this kind is shown, by way
of example, at Fig. 7 whereon 7 is the feed pipe.
In order to properly carry out the sharpening of razor blades it is necessary to
have a holder, such as m Fig. 8, which is provided with a ledge n for catching the
blade B. The holder is so made, as shown, that the blade can be readily inserted
in and removed therefrom. The ledge or stop n of the holder prevents the blade
being accidentally drawn in between the wheels.
The holder m Fig. 9 is for use when grinding tang side faces and the holder m
Fig. 10 for use when grinding tang or tail edges.
The emery wheels d, which are, preferably, hollow and of ring shape are held
in place by means of head-stocks d', fitted on the driving shaft c, in such manner,
as shown, that the wheels can be almost used up, without running the risk of
cracking or splitting through centrifugal action.
By thus using two rotating sharpening or grinding wheels the opposite surfaces
of cutting instruments can be simultaneously sharpened, ground, dressed or polished
throughout almost the whole of their extent, the action of the wheels being
distributed over the whole of the surfaces and being reduced in such manner that
razor blades, for instance, when being ground are not heated or burned.
sharpening is moreover much more uniform than heretofore and the whole surface
of the grinding wheels is utilized. The wheels being held in place, as herein-
before set forth, do not crack or split under centrifugal action even when made
very thin.
The
The grinding wheels or discs at present employed are only partially used on their
periphery.
The new machine is both simple and expeditious in its action, and, by the use

page_text: of holders provided with stops, the sharpened blades can be readily removed and
replaced by other blades without in any way interfering with the action of the
wheels.
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
consider novel and desire to claim is :-
1. The herein before described method of simultaneously grinding, sharpening,
dressing or polishing the opposite symmetrieal or unsymmetrical surfaces of cutting
instruments, consisting in effecting the sharpening and polishing, not on the
periphery of a grinding wheel or disc as usual, but between the end faces of two
grinding wheels or discs revolving in the same direction and adjustable the one
relatively with the other, the instrument being ground having a short reciprocatory
motion, transversely to the direction of the grinding, imparted to it in such manner
that the grinding action is distributed over the whole of the surface to be sharpened
so as to prevent any undue heating or burning during the grinding operation.
2. The apparatus for effecting the above claimed method of grinding consisting
of two grinding wheels or discs having their inner ends used as working surfaces
carried on revolving shafts and adjustable vertically and laterally, said wheels or
discs revolving in the same direction and being so secured in place that they can
be almost entirely use up without cracking or splitting, substantially as herein-
before set forth.
3. In a machine of the class set forth, feeding the grinding or polishing substance
to or near to the axis of rotation of the grinding wheels in order to utilize the
centrifugal force developed by the wheels for equally distributing the substance
over their working surfaces, substantially as set forth.
4. In a machine of the class set forth, a holder provided with stops or ledges
such as n for preventing the instrument being accidentally drawn in between the
grinding wheels, whilst at the same time permitting its free removal, substantially
as set forth.
Dated this 15th day of June 1896.
H. D. FITZPATRICK,
70 Wellington Street, Glasgow, Agent.