CERTAIN IMPROVEMENTS IN THE MACHINERY FOR GRINDING, SMOOTHING, AND POLISHING PLATE GLASS, WINDOW GLASS, MARBLE, SLATE, AND STONE, AND ALSO GLASS VESSELS, GLASS SPANGLES, AND DROPS
Year: 1836

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, we, ROBERT
GRIFFITHS, of Birmingham, in the County of Warwick, Machine Maker, and
JOHN GOLD, of the same place, Glass Cutter, send greeting..
WHEREAS His present most Excellent Majesty King William the Fourth,
by His Letters Patent under the Great Seal of Great Britain, bearing date
at Westminster, the First day of September, in the seventh year of His
reign, did, for Himself, His heirs and successors, give and grant unto us, the
said Robert Griffiths and John Gold, His especial licence, full power, sole pri-
vilege and authority, that we, the said Robert Griffiths and John Gold, our
exors, admors, and assigns, or such others as we, the said Robert Griffiths and
John Gold, our exors, admors, or assigns, should at any time agree with,
and no others, from time to time and at all times during the term of years
therein expressed, should and lawfully might make, use, exercise, and vend,
within England, Wales, and the Town of Berwick-upon-Tweed, our Invention
of "CERTAIN IMPROVEMENTS IN THE MACHINERY FOR GRINDING, SMOOTHING, AND
POLISHING PLATE GLASS, WINDOW GLASS, MARBLE, SLATE, AND STONE, AND
ALSO GLASS VESSELS, GLASS SPANGLES, AND DROPS;" in which said Letters
Patent is contained a proviso that we, the said Robert Griffiths and John
Gold, or one of us, shall cause a particular description of the nature of our
said Invention, and in what manner the same is to be performed, to be
inrolled in His said Majesty's High Court of Chancery within six calendar

page_text: and at large appear.
NOW KNOW YE, that in compliance with the said proviso, we, the said
Robert Griffiths and John Gold, do hereby declare the nature of our Inven-
tion, and the manner in which the same is to be performed, are fully
described and ascertained in and by the following statement thereof, reference
being had to the Drawing hereunto 'annexed, and to the figures and letters
marked thereon (that is to say):
DESCRIPTION OF THE DRAWING.
Figure 1 represents a front view in elevation (partly in section) of a machine
for grinding arranged or combined according to our Invention. Figure 2 is
an end view of Figure 1. Figure 3 is an elevation of a table without the
grinders. Figure 4 is a plan of the table and grinders. Figure 5 represents
the stationary pulley or drum on to which the driving band or strap is placed
when the grinding portion of the machine is moved from one table to another
table. Figure 6 represents an under side view or plan of a polisher, consisting
of a plate of metal or other suitable material, having several projecting surfaces
covered with felt, wash leather, or other. suitable material for polishing the
glass or other surface, these polishers being mounted. on axes. similar to
.the grinding mills hereafter described: The description hereafter given of
such grinding mills will apply also to the polishers so far. as the means of
.mounting them in suitable bearings and frame, and giving a compound rotatory
and traversing, motion thereto.
.
In each of the above Figures of the Drawing the same letters are used to
indicate similar parts; a, a, being the main. or driving shaft, which receives
motion from a steam engine or other suitable power; by a band or strap
applied to a drum affixed on the main shaft a, a, or such main shaft: may be
driven by means of cog wheels, as is well understood. c, c, are bearings of the
.main shaft a,.a.. These. bearings are shewn to be affixed on the upper surface
of sleepers, supported by masonry, and it is important that the whole machinery
should be as little liable to vibration as possible. On the main shaft a, a,
are affixed the beveled toothed wheels d, d, which take into and drive the beveled
toothed wheels e, e, on the upright shafts f, f, which turn in bearings affixed
.to the sleepers, which, as above stated, also carry the bearings of the main
shaft a, a, as is clearly shewn in the Drawing. The upright shafts fif, also
turn in suitable openings or bearings formed on the framing 9, 9, which is
firmly bolted to the flooring of the workshop. On the upper ends of the

page_text: shaftsff, are affixed what we call the tables h, h, which consist of circulalar
plates of cast iron or other suitable material, as is clearly shewn in the various
Figures of the Drawing. i, i, are troughs surrounding the outer circumference.
of the tables h, h, in order to receive and conduct away the water and other.
materials thrown off from the tables in the act of grinding. These troughs
are supported by legs j,j, bolted to the floor. On the main shaft a, a, are.
affixed the drums b, b, and by means of 'bands or straps k, k, the motion
of the main shaft is communicated to the shaft l, which turns in bearings
at each end of the frame m, m, which carries the rotatory grinders or.
mills n, n, which are circular plates of cast iron or other suitable mate-.
rial, there being a drum o affixed on the shaft l, which is actuated by the strap
or band k from the drum b affixed to the main shaft. The frame m, m, is
what we call the "grinder carriage," "the smoother carriage," "the polisher
carriage," according as the apparatus applied thereto is used for grinding,
smoothing, or polishing, but that shewn in the Drawing is for grinding, and we
will therefore confine ourselves, in the first instance, to describing the machine.
as shewn in the Drawing. The carriage m, m, consists of two end framings,.
supported by and moving on four wheels or rollers p, p, which turn on axes
which are carried by the descending arms q, q; the upper ends of these arms ·
are capable of turning in sockets formed in the lower parts of the end.
framings m, m, of the carriage, and such arms are capable of being held to
the desired position by means of set screws r, r. The wheels p, p, move on.
and are guided by tramways or rails 3, s, as are clearly shewn in the Drawing;.
by this arrangement the carriage m, m, may be run from one table to another;
thus, supposing the plate of glass laid on the table, Figure 1, be finished so far as
the grinding part of the process, the carriage m, with the grinders or mills n, n,.
may be run away from such table, Figure 1, by passing along the tramways or
rails, and when clear of the table and on the tramways or rails affixed at
right angles to these at 8, s, the wheels p, p, are then to be turned to a position
at right angles to their former position, and their arms affixed in the sockets
by the set screws; the carriage m may then be run along such second rail or:
tramway till the carriage comes opposite the table, Figure 3, whereon is placed:
plate or plates of glass ready to undergo the process of grinding, when the
wheels pare again turned in order to run into the trams or rails s, s, of such
second table, and in the meanwhile a carriage having suitable apparatus for.
smoothing is to be run into the trams or rails s, s, of Figure 1, in order to:
smooth the glass which has been ground by the previous process, and when:
the smoothing process is complete the carriage is to be run away from the.
table, Figure 1, in order to make way for a carriage having polishing appa-:
ratus; thus, by having a series of tables and carriages the processes of grinding,
$

page_text: smoothing and polishing may be carried on without one process waiting
for the other. The carriage m, m, consists of the two end framings above.
described, and a framing which connects the two end framings, as is clearly
shewn in the Drawing. t, t, is a frame which carries the bearings of the.
spindles or axes v, v, of the grinders or mills, there being straight angular.
edges w, w formed at the top and bottom of the frame t, t, these edges,
being formed truly parallel in order to ensure the frame t, t, being caused.
to traverse evenly over the surface which is being ground, and these.
angular edges work in guides x, x, affixed to the framing m, m, as is.
clearly shown. On the axis or shaft 7 is affixed the worm or screw y, which
takes into and drives the toothed wheel z, turning on an axis affixed to the
frame m. To the wheel z is affixed (by a screw and nut) a crank pin A,.
which is capable of being placed nearer to or further from the centre of the
wheel z, there being a slot cut in one of the spokes for that purpose, as is
clearly shown in Figure 1. B is a connecting rod moving at one end on the
crank pin A, and at the other end it is connected by a pin joint to the frame
t,t; hence, in the revolving of the wheel z, the frame t, t, will be caused to.
traverse from end to end of the machine, and the spindles of the grinders or
mills n being carried by such frame, the mills or grinders, in addition to their
rotatory motion communicated as hereafter described, will also have a motion
traversing from end to end, as will readily be understood on an examination
of the Drawing. On the spindles or axes of the grinders or mills are
affixed bevilled toothed wheels C, C, which taking into are driven by
the toothed wheel D, D, on the axis or shaft l, such wheels D, D, being
capable of sliding on the shaft 1, but are caused to turn therewith by projecting
surfaces or feathers, as is well understood by mechanics; hence as the frame
t, t, is caused to traverse the wheels D, D, are also caused to move to and fro
on their shaft l, in order to be in proper position to drive their respective,
wheels C, C; and in order to produce such movement of the wheels D, D,
on the shaft, the levers E are employed, such levers moving on axes affixed
to the frame t, t, as is clearly shewn; but the only object of having such
axes to the levers E is, that either of the wheels D may be thrown out of action
with respect to its wheel C, for it will be seen that one end of each lever E
lies within a groove formed in the boss or nave of its wheel D, the other end of
each lever being affixed to the frame t, t, by a set screw, as is clearly shewn
at Figure 1, and in this Figure it will also be seen that there are holes in
the frame to the left of those to which the levers E are now affixed, and it will
be evident that if the set screws were moved with their levers and affixed in
such holes the wheels D would be thrown out of gear, and the mills or
grinders would no longer receive rotatory motion; hence the workman may

page_text: work only with one mill or with two, as he may desire. The spindles or
axes of the mills or grinders n, n, are capable of being raised or lowered in
their bearings by being slided up or down, and they are retained in their proper
positions when at work by means of the levers F, which each move on a fulcrum
at G on brackets affixed to the frame t,t, as is clearly shewn in the Drawing;
through each of the levers F is an adjusting screw which rests on the
frame t, t, by which means the grinders or mills are adjusted to their proper level,
there being studs or projections on the spindles or axes of the mills or grinders
which rest on the levers F; and in order to give some slight play to the
grinders or mills n, n, the levers F are constantly balanced by weights II
suspended by chains which are connected to the levers F, and pass over
pulleys, as is clearly shewn. Having thus described the nature of the
machinery, and the mode of combining the same, it will readily be understood
by a workman acquainted with the grinding, smoothing, and polishing of
glass, that if a plate or plates of glass be placed and affixed on the table h of
Figure 1 (in like manner to that employed for fixing glass when to be ground
as heretofore practised), on the mills or grinders being brought on to the
surface thereof, and motion communicated to the machinery, there will be
rotatory motion to the table h, and also rotatory motion to the mills or
grinders n, n, together with the to and fro motion of the mills or grinders, as
has been before described, which will quickly grind an even and equal surface
to the glass, the workman keeping a constant supply of sand or suitable grit
and water for that purpose; and when such surface has been sufficiently
ground, the smoothing process is next to be performed by means of the
machinery before described, using in this process emery and water, or other
suitable materials. A plate or plates of glass may be affixed to the under
surface of mills, such as has been described for grinding, and such affixing of
a plate or plates of glass may readily be performed by the aid of plaster of
Paris; and such mills being mounted on like carriages m, m, being run into
position in respect to the surface which has been ground, may readily perform
the process of smoothing, being aided by the usual materials heretofore
employed in that part of the process. The smoothing process being completed,
a carriage m, m, having the polishers, Figure 6, is next to be brought to act
on the smoothed surface of glass on the table h, and by means of crocus or
other well known polishing materials usually employed, the process of polishing.
is to be performed.
In the foregoing description we have confined ourselves to the grinding,
smoothing, and polishing of glass; but it will be evident that if slabs of marble,
slate, or stone be affixed on the table h by plaster of Paris or other suitable

page_text: material, the same may be ground, smoothed, and polished by machinery,
combined in like manner to that above described, using suitable grit and
other materials for those processes, such as are now employed when the same
are performed by the means at present known. And further, the description
of glass vessels which are capable of being ground, smoothed, and polished
by the above machines are shallow vessels, such, for instances, as are
called "salts," and merely intended to grind the bottoms thereof level;
and in order to accomplish this object, such vessels are to be inverted and
affixed by plaster of Paris or other suitable means, in order to produce an even
or nearly even surface, on the table h; and such is to be the case when the
machinery is to be applied to glass spangles and drops; the same are to be
imbeded in plaster of Paris or other suitable material, in order to produce
an even surface, when the process of grinding, smoothing, and polishing may
be performed thereto in like manner to what has been described for plates of
glass.
It will be seen from the foregoing description that the main object of our
Invention is to obtain a traversing action, in conjunction with the rotatory
motion of the grinders or mills n, n, and to the smoothers and polishers, in
order that the difference of effect which would otherwise be consequent on the
difference of speed at which any particular point or part of the mills travel
depending on the distance from the center. It consequently follows that a
like effect may be obtained by giving a compound rotatory motion and a
traversing motion to the table h, in place of giving the same to the mill m;
and it will be evident that the carriages having rotatory and traversing motion
to the mills m, whether for grinding, smoothing, or polishing, may be as fully
employed on stationary tables or to a table having a traversing motion, in
which last case the traversing of the mills may be dispensed with.
Having thus described the nature of our Invention, and the manner of
combining the same, we would have it understood that we lay no claim to the
various parts séparately of which the same is composed; and it should also be
remarked that variations in the details may be made without departing from
the Invention, provided the principle of the combination be retained.
We do hereby declare that what we claim as our Invention is,―
First, the combination of the parts constituting what is called the carriage m,
when the mill or mills n have a rotatory and a traversing motion communicated
thereto for the purpose of grinding, smoothing, and polishing of plate glass,
window glass, marble, slate, or stone or glass vessels, or glass spangles or
drops, as above described. And,
Secondly, we claim the giving a traversing motion to the table acted on by

page_text: a rotatory mill or mills when used for grinding, smoothing, or polishing plate
glass, window glass, marble, slate, or stone or glass vessels, or glass spangles
or drops, as above described; but we do not claim the giving a traversing
motion to a table when not acted on by rotatory mills, or having rotatory
motion applied to itself in addition to the traversing motion.
In witness whereof the said parties to these Presents have hereunto set
their hands and seals, the Twenty-fourth day of February, in the year
of our Lord One thousand eight hundred and thirty-seven.