IMPROVE- MENTS IN GRINDING AND POLISHING GLASS, AND IN THE MACHINERY OR APPARATUS EMPLOYED THEREIN
Year: 1863

page_text: LETTERS PATENT to John Henry Johnson, of 47, Lincoln's Inn Fields,
in the County of Middlesex, Gentleman, for the Invention of "IMPROVE-
MENTS IN GRINDING AND POLISHING GLASS, AND IN THE MACHINERY OR
APPARATUS EMPLOYED THEREIN." -A communication from abroad by
James Dodge, of Waterford, Saratoga County, State of New York,
United States of America.
Sealed the 7th June 1864, and dated the 15th December 1863.
PROVISIONAL SPECIFICATION left by the said John Henry Johnson at
the Office of the Commissioners of Patents, with his Petition, on the 15th
December 1863.
I, JOHN HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of
Middlesex, Gentleman, do hereby declare the nature of the said Invention
for "IMPROVEMENTS IN GRINDING AND POLISHING GLASS, AND IN THE MACHINERY OR
APPARATUS EMPLOYED THEREIN," a communication to me from abroad by James
Dodge, of Waterford, Saratoga County, State of New York, United States of
America, to be as follows:-
This Invention relates to an improved mode or method of grinding and
polishing glass, and to a peculiar construction, arrangement, and combination
of mechanism to be employed for that purpose.
According to this Invention it is proposed to employ either one or two

page_text: grinding or polishing stones or wheels, to which a lateral or sidelong traversing
motion is imparted simultaneously with their rotatory motion. When two
stones or wheels are employed, the sheets or plates of glass to be ground or
polished are placed each in a separate frame containing a yielding bed of
india-rubber or other suitable material, against which the sheet or plate rests.
Two of these frames, each having a sheet or plate of glass fitted therein, are
placed back to back, so as to leave the two outer faces of the sheets or plates
exposed to the action of the two grinding stones or polishing wheels, between
the peripheries of which the frames are made to traverse vertically and hori-
zontally, so as to present the entire surfaces to the action of the stones or
wheels. When acting upon a single sheet or plate of glass, one stone or
wheel only need be employed acting upon the surface of the glass exposed in
the frame or holder, the frame being held up to the grinding or polishing
surface by special rollers. The bearings of the stones or wheels should be
made adjustable so as to enable sheets or plates of different thicknesses to be
placed between or against them.
According to another part of this Invention it is proposed to grind or
polish plates or sheets of glass by placing such plates or sheets upon yielding
beds carried on rocking tables, which are fitted to the circumference of a
revolving surface or cylinder. Suitable arrangements are employed for
ensuring the several tables assuming a tangential position with regard to the
grinding surface or wheel as they pass in front of and in contact therewith.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said John Henry Johnson in the Great Seal Patent Office on
the 15th June 1864.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, Jonn
HENRY JOHNSON, of 47, Lincoln's Inn Fields, in the County of Middlesex,
Gentleman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters.
Patent, bearing date the Fifteenth day of December, in the year of our Lord
One thousand eight hundred and sixty-three, in the twenty-seventh year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto me,
the said John Henry Johnson, Her special license that I, the said John Henry
Johnson, my executors, administrators, and assigns, or such others as I, the said.
John Henry Johnson, my executors, administrators, or assigns, should. at any

page_text: time agree with and no others, from time to time and at all times there-
after during the term therein expressed, should and lawfully might make,
use, exercise, and vend, within the United Kingdom of Great Britain and
Ireland, the Channel Islands, and Isle of Man, an Invention for "IMPROVE-
MENTS IN GRINDING AND POLISHING GLASS, AND IN THE MACHINERY OR APPA-
RATUS EMPLOYED THEREIN," a communication to me from abroad by James
Dodge, of Waterford, Saratoga County, State of New York, United States of
America, upon the condition (amongst others) that I, the said John Henry
Johnson, my executors or administrators, by an instrument in writing under
hand and seal, or under the hand and seal of one of them, should parti-
cularly 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 John Henry Johnson, do hereby declare
the nature of the said Invention, and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement, reference being had to the accompanying Drawings, and to the
letters and figures marked thereon, that is to say :-
My said Invention relates to an improved mode or method of grinding and
polishing glass, and to a peculiar construction, arrangement, and combination
of mechanism to be employed for that purpose.
According to this Invention it is proposed to employ either one or two
grinding or polishing stones or wheels, to which a lateral or, sidelong traversing
motion may be imparted: simultaneously, if desired, with their rotatory
motion. When two stones or wheels are employed, the sheets or plates of
glass to be ground or polished are placed each in a separate frame, or both in
the same frame, containing a yielding bed of india-rubber or other suitable
material between the two sheets or plates, against which the sheets or plates.
rest. Two of these frames, each having a sheet or plate of glass fitted
therein, are placed back to back, or a single frame may be used containing
the two sheets or plates of glass, so as to leave the two outer faces of the
sheets or plates exposed to the action of the two grinding stones or polishing
wheels, between the peripheries of which the frames are made to traverse in a
vertical and horizontal or lateral direction, so as to present the entire surfaces
to the action of the stones or wheels.. When acting upon a single sheet or
plate of glass, one stone or wheel only need be employed acting upon the
surface of the glass exposed in the frame or holder, the frame being held up
to the grinding or polishing surface by special rollers. The bearings of the

page_text: stones or wheels should be made adjustable so as to enable sheets or plates of
different thicknesses to be placed between or against them.
According to another part of this Invention it is proposed to grind or
polish plates or sheets of glass by placing such plates or 'sheets upon yielding
beds carried on rocking tables, which are fitted to the circumference of a
revolving surface or cylinder: Suitable arrangements are employed for
ensuring the several tables assuming a tangential position' with regard to the
grinding surface or wheel as they pass in front of and in contact therewith...
And in order that the said Invention may be fully understood, I shall now
proceed more particularly to describe the same, and for that purpose I shall
refer to the several Figures on the two Sheets of Drawings hereunto annexed,
the same letters of reference indicating corresponding parts in all the cor-
responding Figures.
Figure 1 on Sheet 1 of my Drawings represents a sectional elevation of
one form of my improved machine for grinding and polishing sheets or plates
of glass of large dimensions, and Figure 2 is a corresponding transverse vertical
section of the same.
A is 'the main framing of the machine, and B, B', are two rotatory grind-
stones or polishing wheels driven by the straps or gearing, and carried by the
shafts C, C, supported in bearings on the main framing. If desiréd, a lateral
or to-and-fro sidelong motion may be imparted to these stones or wheels by
any well-known mechanical contrivance, in which case the journals of the
shafts C, C, should be lengthened or prolonged beyond the bearings to allow
of such lateral traverse. D, D, are the sheets or plates of glass to be ground
or polished; they are contained in a frame E, and have a sheet of india-
rubber F interposed between them to allow the sheets or plates to yield
slightly when passing between the stones or wheels B, B¹. The frame E is
carried in an outer frame, within which it is caused to move to and fro laterally
along the two guide rails H, H, in such frame. The object of this lateral
motion is to cause the stones or wheels B, B¹, to operate equally over the
entire width of the plate, and so prevent any scoring or channelling of the
sheets or plates by the extreme edges of the stones or wheels. I is a long
nut secured to one side of the frame E; within which nut works one end of
"a screw spindle K; the other end of which is supported in a bearing in the
outer frame, and is provided with a pair of ratchet wheels L, L'; having their
respective teeth in reverse directions. By turning this screw, as will be
herein-after explained, a lateral traverse will be imparted to the frame E;
the outer frame slides vertically in slots or other suitable guides M in the
'main framing, such vertical or up-and-down motion being imparted to it by

page_text: the spur pinions N, N, which gear into the vertical racks O, O, formed on 'or
attached to the sides of the outer frame. These pinions are fast on 'a trans-
verse shaft P supported at each end in bearings in the main framing, and
driven by any well-known arrangement of self-acting reversing gear, as shewn
at Q in my Drawings, of which a, b, c, represent the driving pullies. When
the driving strap is shifted from the loose pulley b to the pulley a, the outer
frame with the inner frame E will be caused to move vertically in one'
direction, and when shifted again to the pulley c the motion will be reversed,
and the frame will move in an opposite direction, such up-and-down motion
being maintained during the whole time the sheets or plates are subjected to
the action of the stones or wheels, and thus their entire length will be equally
ground or polished as well as their width.. Each time the outer frame arrives
at the bottom of its stroke, that is to say, when the extreme end of the sheets
or plates have been brought down to the points of contact with the stones or
wheels, one or other of two palls R, R', carried by the main framing will
strike against the teeth of one or other of the two ratchet wheels L, L',
according to which of the two palls may be set in action (in the Drawing
Figure 1, the pall R is shown thrown back out of action), and consequently
the screw spindle K will be turned slightly in one direction or the other, and
will cause the framè E to move laterally along its guide rails H at each down-
ward traverse of the outer frame. S, S, are rollers carried by the main
framing, and bearing against the surfaces of the sheets or plates of glass in
order to keep the same in their places in the frame or holder E. The grind-
stones or polishing wheels B, B¹, are moved up to or from their work by the
screw spindles T, one at each side of the machine for each stone or wheel, and
each pair of these screw spindles are rotated by means of the cross shafts U
and mitre gearing V, and work in nuts U¹ on the under side of the plummer
blocks of the stones or wheels. Each shaft is rotated by a hand wheel W.
keyed thereon..
Figure 1 on Sheet 2 of my Drawings represents a side elevation of a
machine for grinding or polishing sheets or plates of glass of smaller
dimensions than can be conveniently ground or polished in the machine repre-
sented on Sheet 1 of my Drawings; Figure 2 is an end elevation of the
same; Figure 3 is a longitudinal vertical section, and Figure 4 is an enlarged
detail of the machine. In this machine, which is also applicable to the
grinding of prisms or glass pendents, only one grindstone or polishing wheel is
employed.
A is the main framing of the machine, and B is the driving shaft carrying
a large driving pulley C; D is another driving pulley keyed on the axis E of

page_text: the grindstone or polishing wheel F, such pulley being driven by an inde
pendant strap; G is a spur pinion keyed on the shaft B, and gearing into a
large spur wheel H fast, on the shaft I, which carries the revolving drum or
cylinder K; to this drum are attached a number of rocking tables L, shown,
more clearly on a larger scale in Figure 4. These rocking tables have inner
flanges a cast thereon, in, which flanges are formed cured slots b, which work
on studs or pins c, c, secured to each side of the drum or cylinder near the
periphery thereof. The several tables are thus left free to rock upon the
studs or pins c, and to assume a tangential position as regards the cylinder, and
grindstone or polishing wheel when passing in front thereof, as is clearly
shewn in Figure 4. This adjustment of each rocking, table as it, approaches
the stone or wheel is accomplished by the following self-acting arrangement:-
M is a stop or catch secured to one or both sides of the outer casting. N of
the cylinder on the inner surface, thereof, and O is a stud or pin carried on
one or both the inner flanges a of the rocking tables; P is one. of two other
studs or pins, also fitted to the flanges a on, the outside thereof; and Q is a
vertical guiding slot or groove formed in each side of the outer casing N.
As each rocking table is brought round by the revolution of the drum or
cylinder, the stud or studs O strike against the fixed stop or stops M, and
cause the table to be tipped up into a vertical position just as its forward end
approaches the stone or wheel. The table is held firmly and without shaking
in this position during the time it is passing down in front of the stone or
wheel by the steady pins P, which enter the guiding, slots Q, and pass, along
such slots from the top downwards. During the time the steady pins. are in
the slots Q, the table is held in a vertical position, and tangential to the
stone or wheel and cylinder. By the time the table has passed the stone or
wheel, the pins P will have emerged from the lower ends of the guiding
slots; the tables are each adjusted to their original positions again by coming
in contact with a curved guiding plate or bar R fixed to the main framing.
On the surface of each of the rocking tables is laid a sheet of india-rubber or
other suitable elastic material d, upon which is placed; the sheet or plate of
glass e to be ground or polished. This sheet or plate is held firmly upon its
bed by a clamp consisting of an angular bar f, which is pressed against one
end of the sheet or plate by the pressing screws g. 9, passing through a flange
or projecting ribh formed on the end of the table. A corresponding flange
or projecting rib h¹ is formed on the opposite end of the rocking table, against
which the end of the sheet or plate of glass is pressed by the action of the
bar and pressing screws. 9 at the other end. The bar fhas slots made in
it, through which pass screws i for: securing it down to the surface of the

page_text: .
table, the slots allowing for the movement of the bar when pressed forward by
the screws g. When operating upon prisms or similar articles of glass, I hold
each prism in its place separately by the end pressure of a metal block k (as
shewn in the detail, Figure 5) acted upon by a block of india-rubber or a
spring 1, which is introduced between the end of the pressing block k and the
raised flange or projection h on the end of the table, or a pressing screw may
be employed for pressing the blocks k against the ends of the prisms, their
opposite ends bearing against the flange h¹. The object; of the iron clamp,
which is shown in Figure 5, is for the purpose of holding an india-rubber
form d for the prism to rest in, these matrices and forms varying in shape for
different shaped prisms. The grindstone or polishing wheel is contained
within an outer casing S, and is adjusted to or from the work according to the
thickness of the glass, or in proportion as the stone or wheel becomes worn by
means of a screw spindle T passing through a nut U on the under side of each
of the plummer blocks which carry the bearings for the stone or wheel; these
screw spindles are rotated simultaneously by means of the level gearing V and
hand wheel W. A lateral or sidelong motion to and fro may be imparted to
the stone or wheel by any well-known arrangement of mechanism, the journals
being left sufficiently long to allow of such motion in their bearings.
Having now described and particularly ascertained the nature of the said
Invention, and the manner in which the same is or may be used or carried
into effect, I would observe, in conclusion, that what I consider to be novel
and original, and therefore claim as the Invention secured to me by the
herein-before in part recited Letters Patent, is,-
1st, the peculiar arrangement and combination of the several parts of
machinery or apparatus for grinding and polishing sheets or plates of glass, as
herein-before described and illustrated on Sheet 1, of my Drawings.
2. The application and use to and in the grinding and polishing of sheets
or plates of glass of a yielding bed of india-rubber or other suitable elastic
material in combination with the peculiar traversing frame or holder for con-
taining the sheets or plates to be operated upon, as herein-before-described
and illustrated on Sheet 1 of my Drawings.
3. The application and use to and in the grinding and polishing of sheets
or plates of glass of the peculiar frame or holder and yielding bed above
referred to, having a vertical and lateral traversing motion imparted thereto in
combination with a pair of horizontal adjustable grindstones or polishing
wheels, or with a single adjustable horizontal grindstone or polishing wheel
and a pressing roller or rollers, as herein-before described and illustrated on
Sheet 1 of my Drawings.

page_text: 4. The peculiar arrangement and combination of the several parts of
machinery or apparatus for grinding and polishing glass, as herein-before
described and illustrated on Sheet 2 of my Drawings.
5. The combination of yielding beds of india-rubber or other suitable elastio
material with rocking tables carried by a revolving cylinder or drum, and
operated in the manner and for the purpose herein-before described.
In witness whereof, I, the said John Henry Johnson, have to this my
Specification hereunto set my hand and seal, the Thirteenth day of
June One thousand eight. hundred and sixty-four.
J. HENRY JOHNSON, (L.s.)