IMPROVEMENTS IN MACHINERY FOR GRINDING AND POLISHING SHEETS OF PLATE AND, OTHER GLASS
Year: 1859

page_text: LETTERS PATENT to George Tomlinson Bousfield, of Loughborough Park,
Brixton, in the County of Surrey, for the Invention of "IMPROVEMENTS IN
MACHINERY FOR GRINDING AND POLISHING SHEETS OF PLATE AND, OTHER
GLASS." A communication from abroad by J. J. Greenough, of Wall.
Street, New York.
Sealed the 25th January 1860, and dated the 5th November 1859.
PROVISIONAL SPECIFICATION left by the said George Tomlinson
Bousfield at the Office of the Commissioners of Patents, with his.
Petition, on the 5th November 1859.
I, GEORGE TOMLINSON BOUSFIELD, of Loughborough Park, Brixton, in the
County of Surrey, do hereby declare the nature of the Invention for "IMPROVE-
MENTS IN MACHINERY FOR GRINDING AND POLISHING SHEETS OF PLATE AND OTHER
GLASS," to be as follows:-
This Invention has for its object improvements in machinery for grinding
and polishing sheets of plate and other glass. In order to grind plates of glass
to an even thickness, the plates of glass are placed on a carriage which slides
on an inclined frame. The inclined frame is twice the length of the sliding
carriage, and above the centre of the inclined frame a grinding cylinder is
supported in such manner that it can be brought nearer to or further from
the inclined frame to regulate the thickness to which the glass shall be ground;
the grinding cylinder is caused to revolve rapidly by a pulley on its axis, being
driven by a driving band, and the cylinder is so supported that in addition to

page_text: its being caused to revolve, an endway motion may be imparted to it by a disc
on the axis of the cylinder working in a grooved cam on an axis to which
motion is communicated from the axis of the grinding cylinder. As the
grinding cylinder revolves the sliding carriage is moved up the inclined frame
and under the grinding cylinder, by means of two screws working in nuts on each
side of the sliding carriage; these screws are caused to revolve by worm wheels
on their axes, taking into worms on an axis to which motion is communicated
from the axis of the grinding cylinder. A hopper containing sand and water
or other grinding material is placed above the grinding cylinder to supply
grinding material between the cylinder and the surface of the glass, and the
grinding material after passing between the cylinder and the glass flows down
over the unground portion of the glass.
In constructing machinery for polishing plate glass according to this Inven-
tion, it is preferred to construct the machine so that two plates of glass may be
polished at the same time; but machines constructed in a similar manner to
that herein-after described, may be made for polishing only one plate at a time.
When polishing two plates at a time, the plates are placed on two horizontal
tables fixed to a framing at a short distance apart; between these two tables
there is a carriage which slides on rails on each side of the tables, and to this
carriage a to-and-fro motion is communicated by means of a crank or other-
wise. At each end of the carriage there is a screw which extends across the
carriage, and turns in bearings in each of its sides; one axis of each screw
projects beyond the side of the carriage, and on each of these axes there is a worm
wheel which takes into a worm that is capable of sliding along a square bar.
These bars are parallel with the rails on which the carriage slides, and pro-
jections on the carriage work in grooves in the worms, so that as the sliding
carriage is moved to and fro by the crank, the worms are caused to move
along the square bars, and are thus kept in gear with the worm wheels; on
each of the bars there is a bevil wheel, into each of which another bevil wheel
gears; on the axes of these latter bevil wheels there are two fast and one loose
pulley, one fast pulley on each axis is driven by a .crossed band, and the other
fast pulley by an uncrossed band, and these bands are guided by forks, so that
when one band is on its fast pulley the other is on the loose pulley; motion is
communicated to the two crossed and the two uncrossed bands from a drum or
the driving axis. On the screws carried by the sliding carriage, nuts work
which are prevented from rotating by their under sides sliding on rails carried
by the sliding carriage, so that the nuts are caused to traverse along the screws
in one direction or another, according to the direction in which the screws are
revolved.

page_text: The forks which guide the driving bands are connected to bars, which
pass from side to side of the machine, and which slide in projections from the
framing; on each bar are two adjustable stops which project out from the bars
a distance equal to the movement of the sliding carriage; between these stops
the nuts working on the screws carried by the sliding carriage move, and on
each of the nuts there is a projection, which as the nuts are moved across the
carriage by the screws come against one or other of the projecting stops, and
so moves the bar to which it is attached sideways, this movement causes the
fork on the bar to move the band, which before was giving motion to the screw,
on to the loose pulley, and at the same time moves the band which was on the
loose pulley on to its fast pulley, and the screw is thus caused to rotate in the
opposite direction. By this means the nuts working on the screws are moved
to and fro across the tables at the same time that they are moved to and fro
with the sliding carriage; the polishing blocks are connected to these nuts in
such manner that they are moved by the nuts backwards and forwards, and from
side to side across the plate of glass on the tables, but are free slightly to rise
or fall independently of the nuts, so that the blocks always rest flat upon the
glass. The blocks are also made in short lengths, and are connected together
in a similar manner, so that each length may rise or fall independently of the
other.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said George Tomlinson Bousfield in the Great Seal Patent Office
on the 4th May 1860.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, GEORGE
TOMLINSON BOUSFIELD, of Loughborough Park, Brixton, in the County of.
Surrey, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Fifth day of November, in the year of our
Lord One thousand eight hundred and fifty-nine, in the twenty-third year of.
Her reign, did, for Herself, Her heirs and successors, give and grant unto,
me, the said George Tomlinson Bousfield, Her special licence that I, the said
George Tomlinson Bousfield, my executors, administrators and assigns, or such
others as I, the said George Tomlinson Bousfield, my executors, administrators,
and assigns, should at any time agree with, and no others, from time to time
and at all times thereafter during the term therein expressed, should and
lawfully might make, use, exercise, and vend, within the United Kingdom

page_text: of Great Britain and Ireland, the Channel Islands, and Isle of Man, an
Invention for "IMPROVEMENTS IN MACHINERY FOR GRINDING AND POLISHING SHEETS
OF PLATE AND OTHER GLASS," a communication from abroad by J. J. Greenough,
of Wall Street, New York, upon the condition (amongst others) that I, the said
George Tomlinson Bousfield, my executors or administrators, by an instru-
ment in writing under my, or their, or one of their hands and seals, should
particularly describe and ascertain the nature of the said Invention, and
in what manner the same was to be performed, and cause the same to be
filed in the Great Seal Patent Office within six calendar months next and
immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said George Tomlinson Bousfield, do hereby
declare the nature of the said Invention, and in what manner the same is to
be performed, to be particularly described and ascertained in and by the
following statement thereof, that is to say:
This Invention has for its object improvements in machinery for grinding
and polishing sheets of plate and other glass. In order to grind plates of glass
to an even thickness, the plates of glass are placed on a carriage, which slides
on an inclined frame; the inclined frame is twice the length of the sliding car-
riage, and above the centre of the inclined frame a grinding cylinder is
supported, in such manner that it can be brought nearer to or farther from the
inclined frame, to regulate the thickness to which the glass shall be ground;
the grinding cylinder is caused to revolve rapidly by a pulley on its axis, being
driven by a driving band, and the cylinder is so supported, that in addition to
its being caused to revolve, an endway motion may be imparted to it by a disc
on the axis of the cylinder, working in a grooved cam on an axis, to which
motion is communicated from the axis of the grinding cylinder. As the
grinding cylinder revolves, the sliding carriage is moved up the inclined frame
and under the grinding cylinder, by means of two screws working in nuts on
each side of the sliding carriage; these screws are caused to revolve by worm
wheels on their axes, taking into worms on an axis, to which motion is com-
municated from the axis of the grinding cylinder; a hopper containing sand
and water, or other grinding material, is placed above the grinding cylinder, to
supply grinding material between the cylinder and the surface of the glass, and
the grinding material after passing between the cylinder and the glass, flows
down over the unground portion of the glass.
In constructing machinery for polishing plate glass according to this Inven-
tion, it is preferred to construct the machine so that two plates of glass may
be polished at the same time; but machines constructed in a similar manner
to that herein-after described, may be made for polishing only one plate at a

page_text: time. When polishing two plates, at a time, the plates are placed on two
horizontal tables fixed to a framing at a short distance apart; between these
two tables there is a carriage which slides on rails on each side of the tables,
and to this carriage a to-and-fro motion is communicated by means of a crank,
or otherwise. At each end of the carriage there is a screw, which extends
across the carriage and turns in bearings in each of its sides; one axis of each
screw projects beyond the side of the carriage, and on each of these axes there
is a worm wheel which takes into a worm that is capable of sliding along a
square bar; these bars are parallel with the rails on which the carriage slides,
and projections on the carriage work in grooves in the worms, so that as the
sliding carriage is moved to and fro the crank, the worms are caused to
move along the square bars, and are thus kept in gear with the worm wheels.
On each of the bars there is a bevil wheel, into which another bevil wheel
gears; on the axes of these latter bevil wheels there are two fast and one
loose pulley; one fast pulley on each axis is driven by a crossed band, and the
other fast pulley by an uncrossed band, and these bands are guided by forks,
so that when one band is on its fast pulley the other is on the loose pulley.
Motion is communicated to the two crossed and the two uncrossed bands from
a drum on the driving axis; on the screws carried by the sliding carriage nuts
work, which are prevented from rotating by their under sides sliding on rails
carried by the sliding carriage, so that the nuts are caused to traverse along
the screws in one direction or another, according to the direction in which the
screws are revolved; the forks which guide the driving bands are connected to
bars which pass from side to side of the machine, and which slide in projec-
tions from the framing; on each bar are two adjustable stops which project
out from the bars a distance equal to the movement of the sliding carriage;
between these stops, the nuts working on the screws carried by the sliding
carriage move, and on each of the nuts there is a projection, which, as the
nuts are moved across the carriage by the screws, come against one or other of
the projecting stops, and so moves the bar to which it is attached sideways;
this movement causes the fork on the bar to move the. band, which before was
giving motion to the screw on to the loose pulley, and at the same time moves
the band which was on the loose pulley on to its fast pulley, and the screw is
thus caused to rotate in the opposite direction. By this means the nuts
working on the screws are moved to and fro across the tables at the same time
that they are moved to and fro with the sliding carriage; the polisbing blocks
are connected to these nuts in such manner that they are moved by the nuts
backwards and forwards and from side to side across the plates of glass on the
tables, but are free slightly to rise or fall independently of the nuts, so that the

page_text: blocks always rest flat upon the glass; the blocks are also made in short
lengths, and are connected together in a similar manner, so that each length
may rise or fall independently of the others.
Having thus stated the nature of the said Invention, I will proceed more
fully to describe the manner of performing the same.
DESCRIPTION OF THE DRAWINGS.
Heretofore a great difficulty has been experienced in grinding down the
rough and uneven surface of rough plates of glass, which are often very un-
equal in thickness, sometimes requiring as much as a quarter of an inch to be
ground. off. to level the plate to an equal thickness; this has materially en-
hanced the expense of the manufacture of polished plate glass. By machinery
constructed according to this Invention, plates of glass may rapidly be cut
down to an even thickness, ready for polishing.
Figure 1 represents a side elevation of machinery for grinding the plates of
glass level; Figure 2 is a vertical section; Figure 3 is a section on line x, x,
of Figure 1; Figure 4 is a plan of the machine.
a, a, is the framing of the machine, the sides of which are of the form of a
right-angle triangle; the inclined side of this triangle forms the support of two
rails of iron b, b, extending from the bottom to the top of the frame, and on
them the carriage or bed c, on which the plate of glass to be ground rests is made
to slide. Two screws d, d, are placed in the frame just within the slides or
rails b, and parallel with them; these screws work into nuts on the under side
of the carriage c (clearly seen in Figure 3), and the screws are long enough
to give sufficient motion to the carriage to make it traverse its length; on their
upper ends they bear gear wheels e that gear into worms on a cross shaft f,
at the head or upper point of the frame; this shaft is connected by a band g
with the driving shaft h, on which a grinding cylinder i is affixed, perfectly
cylindrical in form, and straight from one end to the other; its surface is
covered with proper grinding material such as sand, emery, or other suitable
and well-known article. The cylinder i is longer than the width of any plate
of glass to be ground thereby, and the shaft h is hung in boxes that can be
raised or lowered, so as to determine the distance of the surface of the cylinder
from the bed, and thus guage the thickness to which the plate of glass is to be
ground;
a hopper k is affixed in proper position above the cylinder to discharge
a continuous supply of sand and water, or other grinding material, directly
between the surface of the glass and cylinder, when the grinding action takes
place, and this grinding material, after passing that point flows off over the un-
ground surface of the glass below; the discharge orifice of the hopper k, can be

page_text: regulated in any of the ordinary,ways applicable to such devices and well known
to mechanicians. The cylinder, in addition to its rotating movement, has an end.
chase effected by a cam on a countershaft below, said countershaft being
driven by a pinion m on shaft h, that gears into a spur wheel n on the counter-
shaft o, on which there is a grooved cam p that a guide piece on shaft h works
into, that gives said shaft its lateral motion. At the lower end of the carriage
or bed c there is a projecting rib or ledge, against which the lower end of
the plate of, glass rests; when laying on the bed, this is all that is necessary
to keep it in place while grinding. The machine is put in motion by a belt
from the driving power running on the pulley 7 on driving shaft h, by which
the cylinder receives a rapid revolution, as the bed and glass is gradually
drawn upward under its action. Figure 5 represents a plan of the machinery
for polishing, the plates of glass after they have been levelled by the process
above described. Figure 6 is a side elevation; Figure 7 is a vertical longi-
tudinal section; and Figure 8 is a vertical transverse section of the same. a, a,
is the framing of the machine, on which are placed two tables b, one at each
end; these are made of any required size, and one only may be used, but it is
preferred to use two; over these tables a carriage c moves, travelling upon iron
rails at the sides; this carriage c receives a reciprocating motion of about
two or three feet in length from a crank f, or other suitable device on the end
of an upright shaft g, which is driven by bevil gear from a horizontal shaft h.
The ends of the carriage c move over and parallel with the beds b, having rails
extending from side to side, on which blocks c' slide from side to side across the
whole width of the tables, if necessary. These blocks c' receive their lateral
motion from screws k which have their bearings at the corners of the carriage
c, one end of each screw k projects beyond the side of the carriage and receives
a worm wheel on its end that gears, into a worm m which slides along a
square shaft n by which it is turned, said square shaft being parallel to the
motion of the carriage c, thus permitting the worm thereon and the worm
wheel to keep in gear by moving the worm with the carriage by means of an
arm o affixed to the carriage c, entering a groove in said worm m; each of the
square or worm shafts n is geared into another shaft p. parallel to the driving
shaft h, and provided with two fast pulleys p', and between them a loose
pulley p; the shafts p are driven by a large pulley q, from which there is a
straight and a cross band to each shaft p; these belts are guided by shippers
r, so arranged as to hold a straight belt upon a fast pulley p', and a cross belt
upon the loose pulley p", or the reverse, thereby reversing the motion of shaft
n by the shipper. The shippers r are attached to the ends of two square bars s,
which extend across the carriage c, and have bearings in the stationary frame,

page_text: with an endway motion alone permitted them.. Each bar s is furnished with
two adjustable gauges u and u' that project out a distance equal to the motion
of carriage c. The blocks care provided with pins that project upward
high enough to strike said guages u, u'; when they have been moved far
enough laterally by the screw, and by pressing against the guage they slide
the shipper and slip the bands, thereby reversing the motion of the screw and
changing the lateral movement of the blocks. The polishing blocks w are
heavy castings, having a wooden shoe faced with cloth, are hitched into blocks
c in any convenient way, and a series of any required number can be con-
nected together in line sufficient to polish the whole length of the plate of glass
at once; these blocks rest with their whole weight upon the glass, and follow
the motions of the carriage lengthways, and the lateral motion imparted by
the screw, they are provided with the polishing materials usually employed in
the trade.
Having thus described the nature of the Invention, and the manner of per-
forming the same, I would have it understood that what I claim is,―
First, the combination of apparatus for grinding the surfaces of sheets of
plate and other glass, herein described.
And secondly, the combination of apparatus, herein described, for polishing
sheets of plate and other glass.
In witness whereof, I, the said George Tomlinson Bousfield, have here-
unto set my hand and seal, this Third day of May, in the year of our
Lord One thousand eight hundred and sixty.
GEO. T.. BOUSFIELD. (L.S.)
Witness,
W. J. HARRISON,
2, New Court, St. Swithin's Lane,
London.