IMPROVEMENTS IN POLISHING PLATE GLASS, SHEET GLASS, AND OTHER SUBSTANCES
Year: 1858

page_text: (This Invention received Provisional Protection, but notice to proceed with the
application for Letters Patent was not given within the time prescribed
by the Act.)
PROVISIONAL SPECIFICATION left by William Henry Tooth at the Office
of the Commissioners of Patents, with his Petition, on the 29th January
1858.
I, WILLIAM HENRY TOOTH, of Number 9, Sumner Street, Southwark,
in the County of Surrey, Engineer and Ironfounder, do hereby declare the
nature of the said Invention for "IMPROVEMENTS IN POLISHING PLATE GLASS,
SHEET GLASS, AND OTHER SUBSTANCES," to be as follows:-
My said Invention consists of an improvement or improvements in polishing
and finishing plate glass, sheet glass, and other substances upon an ordinary
polishing table, such as is generally used with a reciprocating or to-and-fro
motion to a line of polishing blocks acting upon the glass or other substances
laid upon
the table for the purpose of polishing and finishing it as the table
continues to move under the polishing apparatus.
My said Invention of improvements is for the purpose of subjecting every
part of the surface of the glass in succession to the action of the polishing
blocks, so that those parts near or about the edges or sides of the table may
be rubbed with an equal velocity and continuousness by the blocks to that.
with which the middle portions of the surfaces of the glass are now rubbed.
In a machine of this description it is usual so to regulate the number and
sizes of the polishing blocks, and length of the stroke or extent of the to-and-
fro motion of the machinery across the surface of the table as to confine the

page_text: action of the rubbers to the surface of the glass or other substances upon the
table operated upon.
For the purpose of enabling a manufacturer to employ a larger quantity of
polishing surface in the polishing and finishing the glass or other substance
upon the polishing table of such a machine, I cause an additional block to be
attached to each end of the polishing apparatus, sufficiently long to cover a
space left between the polishing table and a stationary table herein-after
described, and the length of stroke of the crank of the polishing apparatus or
runner, so that the surface of glass across the whole of that part of the table
which is immediately under the polishing apparatus is covered by and
continuously subjected to the action of the polishing blocks and additional
polishing blocks, and in this way I avoid leaving a portion of the glass bare
and without being acted upon alternately at each end of the table, as in polishing
in the ordinary manner.
.
In order to prevent the faces of the additional polishing blocks from being
more worn than those in present use by crossing the edges of the glass laid
upon the table, I place fixed tables of glass or other hard material under the
blocks which project beyond the table at the end of each stroke of the
apparatus, and I place such tables at each side of the course in which the
polishing table traverses backwards and forwards, and with the upper surfaces
of each of such fixed tables in the same plane as the upper surface of the
glass upon the polishing table traversing backwards and forwards between
them. And when the blocks at either end of a row of polishing blocks
project beyond the surface of the polishing table, they will rub upon the
surface of one of the fixed tables above mentioned.
In order to prevent the faces of the polishing blocks from being frayed,
scratched, or otherwise injured by the edges of the glass or other substance
upon the polishing table, and the edges of the fixed tables over which such
blocks may pass during the to-and-fro motion of the apparatus, I fix or place
strips or pieces of metal or other sufficiently hard material, having their edges
rounded off, along the whole length of each of such edges, and I place the
upper sides of such strips or pieces upon the same plane as that above
mentioned.