AN IMPROVEMENT' IN THE MANUFACTURE OF BLADES FOR PENCIL SHARPENERS OR OTHER ARTICLES OP LIKE NATURE
Year: 1858

page_text: LETTERS PATENT to Walter Kittredge Foster, of the State of Maine, of
the United States of America, for the Invention of "AN IMPROVEMENT' IN
THE MANUFACTURE OF BLADES FOR PENCIL SHARPENERS OR OTHER ARTICLES
OP LIKE NATURE."
COMPLETE SPECIFICATION filed by the said Walter Kittredge Foster
at the Office of the Commissioners of Patents, with his Petition and
Declaration, on the 24th February 1858, pursuant to the 9th Section
of the Patent Law Amendment Act, 1852.
TO ALL TO WHOM THESE PRESENTS SHALL COME, BE IT KNOWN
that I, WALTER KITTREDGE FOSTER, of the State of Maine, of the United
States of America, have invented "AN IMPROVEMENT IN THE MANUFACTURE
OF BLADES FOR PENCIL SHARPENERS, OR OTHER ARTICLES OF LIKE NATURE," and
I do hereby declare the nature of my Invention and the manner in which the
same is to be performed, to be fully described and ascertained in and by the
following Specification and the accompanying Drawings:—
In making small blades for pencil sharpeners it has been found very diffi-
cult to hold and support the blanks during the operation of grinding or reducing
them to a wedge form, or one to enable them to operate as cutters. A side
view of one of these cutters or knives is represented in Figure 1, and an end
view in Figure 2, such Figures exhibiting the same in the full size in which it
is usually manufactured.

page_text: My new method, contrivance, or blank holder for supporting the blade
blanks,, gauging them, and aiding in reducing them to a wedge shape, is
denoted in Figures 3 and 4, the former of said Figures being a top view of
it, while the latter is a longitudinal section of it, such contrivance when in
use being employed in connection with a grinding wheel. Figure 5 denotes
a longitudinal section of the blank holder charged with a series of knife
blanks, each of which is rectangular in its transverse section.
In constructing the said holder I take a plate of metal A and form in its
upper surface one or more series of recesses a, a, a. those of each series being
arranged parallel to each other or in such other manner as circumstances may
require. Each recess a is constructed triangular in cross section, and arranged
with respect to the top surface of the plate, as shewn in Figures 4 and 5. It is
intended to receive a knife blank, which on being laid therein by resting
against the two sides of the recess will take an inclined position with respect
. to the top surface of the bed or holder. This holder, so made, is to be used
under a grinding stone or grinder, which should be made to revolve in such a
direction, while it is operating against a knife blank, that such knife blank
shall be forced by the friction of the grinder against the vertical side of the
knife recess, such vertical or shorter side serving as a stop to prevent the knife
blank from being thrown out of the recess by the grinding wheel. From the
above it will be seen, that while the vertical or shorter side of the recess acts
as a stop to maintain the blank within the recess under the abrading action
of the grinding wheel, the longer or inclined side of the recess operates as a
gauge to so hold the blank and direct it properly while it is under the
operation of the grinder, that the said blank may be reduced to a wedge form
or have a triangular shape in transverse section. By the usual mode of
holding a knife blank while it is being ground, viz., by means of nippers or
gripers applied to its two sides, the reduction of the knife blank becomes a
process requiring so much attention and care that a skilful operative can only
make or reduce about one hundred of the blanks per day. By my improved
method of supporting and grinding the blanks an operative (as has been
demonstrated by practice) in one day can reduce or convert into cutters or
knives from ten to fifteen thousand of such blanks, the blank holder being
charged with blanks by children or operatives, who after a little practice can
accomplish the same with great expertness and facility. After a blank has
been reduced on one side, it may be turned over and that side placed down-
ward within the recess so as to bring the other side of the blank uppermost.
Under these circumstances the latter side may be faced or reduced by the
grinding wheel.

page_text: My improvement effects a wonderful reduction in the cost of making small
blades or knives, as will readily be perceived by cutlers or others skilled in
the art of making pencil sharpeners. What I claim for supporting small
pieces of metal and aiding in their reduction to wedges or knife blades under
the action of a grinder or grinding wheel is a gauge, bed plate, or holder,
constructed with recesses, made so as to operate substantially as described,
such bed being moved along under the grinder or the grinder moved over it
in such manner as to successively reduce each of the blanks that may be
within its recesses.
In testimony whereof, I have hereunto set my signature and seal the
4th day of February 1858.
WALTER KITTREDGE FOSTER. (L.S.)