IMPROVEMENTS IN SCHOOL SLATES
Year: 1883

page_text: LETTERS PATENT to Herbert John Haddan, of Kensington, Middlesex for an
Invention of IMPROVEMENTS IN SCHOOL SLATES communicated to him
from abroad by George Gray, Robert Gray, George William Berrey and
George Ormond Clarke all of New York, United States of America-
Manufacturers
COMPLETE SPECIFICATION filed by the said Herbert John Haddan at the
Office of the Commissioners of Patents on the 9th October 1883.
HERBERT JOHN HADDAN, of Kensington, Middlesex IMPROVEMENTS IN SCHOOL
SLATES communicated to me from abroad by George Gray, Robert Gray, George
William Berrey and George Ormond Clarke all of New York, United States of
America, Manufacturers
This invention relates to improvements in that class of school slates in which
the frame is muffled to avoid noise when using the slate, as, on a desk, and it has
for its object to furnish this class of slates at a reduced cost; to render them light,
substantial and durable; to cover the frame with a continuous tubular muffle so
that the slate will rest against such muffle, and thereby avoid rattling, and to
provide a tubular muffle of such construction that no longitudinal seam is visible,
whilst the muffle is permanently and securely retained in position without the
necessity of employing extraneous devices to connect it with the frame.
These objects. I accomplish by the construction of muffle and slate frame
illustrated in the accompanying drawing in which
Fig. 1. is a plan view partly in section of a school slate constructed in accordance
with this invention.
Fig. 2, a cross section of part of the frame and slate on an enlarged scale.
Fig. 3, a plan view of a portion of the muffle or noiseless material, and
Fig. 4, a perspective view of a portion of the sheet metal strip composing the
rigid part of the slate frame.
The letter A indicates the slate, provided with a surrounding frame composed of
a channeled or U-shaped strip of sheet metal. C, and a covering or muffle B, of
noiseless material such as cloth braid.
In constructing this slate frame I take a strip of cloth or similar textile or other
noiseless material and unite the longitudinal edges of the same by stitching or
sewing, thereby imparting to the noiseless material a tubular form. The channeled

page_text: or U-shaped sheet metal strip C is then bent to the required form to surround the
slate frame and the tubular muffle is drawn over the metal strip, or the strip is
inserted through the tubular muffle, when the adjoining ends of the latter are
united by stitching, sewing or by other suitable means.
To conceal the seam or
joint formed by the junction of the ends of the tubular muffle, I arrange over the
same a covering d of cloth or other noiseless material which can be conveniently
secured in place by paste, stitches or other suitable means.
It is not essential to connect the adjoining ends of the sheet metal strip,
inasmuch as the continuous tubular muffle will be found sufficient to confine the
frame in proper position; but such ends of the strip can be united by solder or
otherwise, if desirable.
It will be observed that the channeled or U-shaped sheet metal frame is entirely
surrounded and inclosed by the continuous tubular muffle, and hence when the
frame is secured around the slate A, all the edges of the latter will bear on the
muffle and press the same into the channel or groove formed by the shape of the
sheet metal strip, thereby effectually preventing rattling, whilst due to the fact
that the metal strip is covered by the muffle, the frame is rendered practically
noiseless.
The seam in the muffle, formed by the longitudinal edges of the piece of
noiseless material, is arranged so as to come directly opposite the channel or groove
in the metal strip, and therefore when the parts are brought into position the
edges of the slate will press said seam into the channel or groove in the metal strip,
thereby providing a slate frame with a muffle in which no longitudinal seam is
visible to the eye, which condition is obviously desirable, the article being neat and
attractive, and not liable to become detached.
The sheet metal strip enables the frame to be made light but strong and durable,
while it is muffled by the continuous tube of noiseless material, and by these means
I am enabled to produce a school slate which can be cheaply manufactured and
will be found serviceable and desirable in every respect.
If desired the muffle can be mannfactured in the form of a tube and thus avoid
subsequent stitching of the longitudinal edges to unite them, but in either event it
should be observed that the muffle is retained in proper position without the
necessity of employing extraneous devices to connect it with the frame which it
incloses, which obviously reduces the cost of manufacture.
CLAIMS
1. As an improved article of manufacture, a school slate consisting of a slate and a
surrounding frame composed of a channeled or U-shaped sheet metal strip, inclosed
within a continuous tubular muffle which is confined in position without extraneous
fastening devices, substantially as described.
2. The combination with a school slate, of a channeled or U-shaped sheet metal
strip and a tubular muffle drawn over the metal strip and united at its ends,
substantially as described.
3. The combination with a school slate, of a channeled or U-shaped sheet metal
strip, and a tubular muffle composed of a piece of noiseless material the
longitudinal edges of which are connected by stitching or sewing and which is
drawn over the metal strip and united at its ends, substantially as described.
In witness whereof I the said Herbert John Haddan have hereunto set my
hand and seal this 9th day of October A.D. 1883.
TT
H. J. HADDAY
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