A Pencil Sharpening Attachment for Slates.
Year: 1891

page_text: Date of Application, 10th Mar., 1891
Complete Specification Left, 10th Dec., 1891-Accepted, 16th Jan., 1892
PROVISIONAL SPECIFICATION.
A Pencil Sharpening Attachment for Slates.
We CHARLES SMITH of 99 Chapel Street, Stratford in the City of London, and
GEORGE CHARLES IRWIN of 17 Merchant Street Bow, in the City of London
Engineers do hereby declare the nature of this invention to be as follows:
-
Our invention consists of an attachment for school or other slates and its object
is to enable the slate pencil to be readily and rapidly sharpened.
In carrying the invention into effect we cast a convex piece of iron and attach it,
The convex
convex side outwards to the frame of the slate by any suitable means.
side has at one portion a roughened surface like a second cut file, and at another
portion a surface irregularly roughened to about the nature of surface represented
by number three emery; while another part has the roughness of an ordinary iron
casting. These three grades of roughened surfaces are preferably disposed in
longitudinal bands each band of about equal length and lying parallel to each
other; but the casting may if desired be divided transversely into surfaces of three
degrees of roughness. At each end of the casting we arrange a number of grooves
preferably of V shape of about 1 inch deep. The slate pencil is sharpened by
rubbing the point along the various surfaces and finishing in the grooves at the
ends, and so a point of the required shape is rapidly and accurately produced.
The surfaces may have more or less than three degrees of roughness, and the
casting may be of flat instead of concave shape without departing from our
invention and steel strips may be struck or cut for the purpose and adopted
instead of castings.
Dated this 9th day of March 1890.
CLERK & MARKS,
13, Temple Street, Birmingham, Agents for Applicants.
COMPLETE SPECIFICATION.
A Pencil Sharpening Attachment for Slates.
We, CHARLES SMITH, of 99, Chapel Street, Stratford, in the City of London,
and GEORGE CHARLES IRWIN, of 17, Merchant Street, Bow, in the City of
London, Engineers, 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:―
Our invention consists of an attachment for school or other slates and its object
is to enable the slate pencil to be readily and rapidly sharpened.
In carrying the invention into effect we cast a convex piece of iron and attach it,
convex side outwards, to the frame of the slate by any suitable means. The convex
side has at one portion a roughened surface like a second cut file and at another
portion a surface irregularly roughened to about the nature of surface represented
by number three emery, while another part has the roughness of an ordinary iron
casting. These three grades of roughened surfaces are preferably disposed in
longitudinal bands each band of about equal length and lying parallel to each
other; but the casting may if desired be divided transversely into surfaces of three
degrees of roughness. At each end of the casting we arrange a number of grooves
preferably of V shape of about 1 inch deep. The slate pencil is sharpened by
rubbing the point along the various surfaces and finishing in the grooves at the
ends, and so a point of the required shape is rapidly and accurately produced.
The surfaces may have more or less than three degrees of roughness, and the
Price 621

page_text: casting may be of flat instead of concave shape, without departing from our
invention, and steel strips may be struck or cut for the purpose and adopted instead
of castings.
Referring to the accompanying sheet of drawings which illustrates our invention,
Figure 1 is a stamped plate showing plan, side elevation, and end view. The
three degrees of roughness are indicated at the bands a, b, c, in plan Figure 1 and
grooves are indicated at d and e. We find however that one degree of roughness
answers very well, and in Figures 2 to 6 inclusive only one roughness is indicated
on the surface. In Figure 1 the plate is bent to form projections or spikes f, f
which serve to fasten our attachment to the frame of the slate. In Figure 2 the
projections are shown in a different position. In Figure 3 holes g, g are provided
for attaching by nails and in Figure 4 punched out projections h, h are used for
fastening.
In Figure 5 an oblong attachment is shown fixed to the slate frame at k while a
triangular one is shown at the corner at l. Figure 6 is a plan and end view of the
triangular attachment which may also serve as a corner bracket to strengthen the
slate frame.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what
we claim is :-
A plate of cast or stamped sheet metal, with a roughened surface, the said
plate being arranged for attachment and attached to a slate frame substantially
as and for the purposes hereinbefore described and as illustrated in the accom-
panying drawings.
Dated this 9th day of December 1891
CLERK & MARKS,
13, Temple Street, Birmingham, Agents for the Applicants.