AN IMPROVED METHOD OF AND MACHINERY FOR GRINDING AND POLISHING GLASS
Year: 1878

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake,
& Co., Patent Agents, Southampton Buildings, London, for the Invention of
"
AN IMPROVED METHOD OF AND MACHINERY FOR GRINDING AND POLISHING
GLASS." A communication from abroad by Berthold Dukas, of Freiburg,
Baden, Gerniany.
Sealed the 19th July 1878, and dated the 24th January 1878.
PROVISIONAL SPECIFICATION left by the said William Robert Lake at the
Office of the Commissioners of Patents on the 24th January 1878.
⚫ WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. AN IMPROVED METHOD OF AND MACHINERY
"
FOR GRINDING AND POLISHING GLASS." [A communication from abroad, by
Berthold Dukas, of Freiburg, Baden, Germany.]
The object of this Invention is to provide means for superseding the method and
means hitherto practised for grinding or cutting table or other glass by substituting
an improved method and improved automatic machinery therefor.
In order to grind or cut the facets upon the surface of glass ware, the operator
has hitherto been accustomed to stem the glass against an iron disc, the grinding
process being effected by sand and water together with the swift rotation of the
disc. In this method the damp dust of sand and glass is constantly hurled into
the face of the operator, and great injury is done to the health of the grinders.
The produce besides is small, because this mode of grinding requires great personal
exertion and skill.
The grinder has to divide the circumference of the glass in as many equal parts
as there are facets to be cut upon the same, and. in consequence it seldom happens
that these facets are exactly regular; also the cut is more flat than concave.
My improved method and machinery for grinding glass ware performs the grinding
operation by means of a grinding stone, of particular quality, without any prepa-
ratory treatment with sand. The work for the attendant or operator is reduced to

page_text: little more than feeding the glass to the machine, and taking the same off when it
is completely ground.
The glass is ground quite automatically, and one man may work ten machines at
a time.
The produce of three skilled grinders hitherto has been about one hundred glasses
a day of about thirteen facets each, but by practising this Invention, one man may
do one hundred glasses with ten machines, or thirty times as much work as a good
hand has been able to do heretofore.
The work effected by my improved lathe or machine is mathematically precise,
whereas the result could never be quite exact by the hand work as heretofore
practised.
The glass leaves my improved lathe or machine in a state fit for immediate
polishing. The polish may be effected by a similar lathe, but provided with a
polishing wheel instead of a grinding stone.
A machine or lathe, constructed according to this Invention, is supported by a
bench or table. A shaft carrying a pulley and grinding stone turns with its pointed
ends in bearings in frame pillars. The said shaft is driven by any prime mover.
The said lathe or machine is fixed upon the said bench or table before the grinding
stone; the ground plate being screwed to the table from beneath the same; the
screws may be moved in a slot. Upon this ground plate a circular plate turns
round a vertical spindle. This circular plate is destined to give the glass its parallel
or angular position towards the grinding surface of the stone. The said circular
plate carries a support, which bears the glass in the direction toward the stone;
the glass is mounted between two pillars, carried by a slide and prism of the
support.
The means for mounting the glass depend upon the various forms of the glasses
to be ground. The wedge accordingly will be preferably made of cork, and it may
be easily exchanged for other forms. The foot of the glass is clamped by a con-
centric chuck; ensuring the axis of the glass being exactly the same as that of the
turning wedge and chuck..
.
The support bearing the pillars, between which the glass is mounted, is moved.
towards the grinding stone by means of a lever with a weight. The said lever is
raised by means of a pulley and a cam, and by every descent of this lever the
support with the glass is pressed against the grinding stone. During the descent
of the lever the said pulley and cam are put out of gear. The cutting of a facet
accordingly does not depend upon one turn of the pulley, but solely upon the
grinding action of the stone. The lever will be raised again and the glass removed
from the stone at the moment when the lever arrives at the deepest point of its
way, that is to say, when the facet is cut deep enough. By these means one facet
after another is cut in regular succession, the glass being turned automatically as
much as necessary every time that one facet has been cut.
When the number of facets required has been cut upon the glass, the working
mechanism must be stopped, otherwise the facet first cut would fall again against
the stone, and the glass might easily be injured.
This stopping action is automatically performed by a toothed disc, upon which
the required number of facets has been indicated by a pin. This pin arrests the
mechanism, and the lever will not be raised again when the last number has
been cut.
The glass will be turned automatically at the precise period of every facet being
finished. The pulley which works the said weighted lever operates also a small
arm which, by means of several corresponding levers and a pawl, turns a wheel
with as many teeth as there are facets to be cut.
During the operation of one facet being cut, that is to say, during the descent.
of the said weighted lever, the pulley which works the lever is put out of gear, and
does not gear with the turning mechanism. But as soon as one facet is finished 5
and the lever has arrived at the lowest point the pulley will again come into gear
with the lever and with the arm by which the toothed wheel is turned by one

page_text: tooth. This toothed wheel is in close connection with the glass, and the latter
will be turned every time for such exact part of its circumference, as is indicated by
the number of teeth of the wheel. By these means any number of facets may be
cut upon the glass with the utmost mathematical exactness as regards the equal
partition of the periphery.
This improved lathe or machine performs automatically all the following functions,
that is to say, when the glass is mounted it will be advanced toward the revolving
stone, and when the latter has finished cutting one facet the grinding operation
stops, the glass is drawn backward and turned exactly into the required position.
and the grinding operation commences again, thus continuing till the last of the
desired number of facets has been cut, at which period the grinding and turning
operation will both be stopped. The glass then only needs to be taken
off, and is ready for polishing, which may be done automatically upon a similar
lathe.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed-
by the said William Robert Lake in the Great Seal Patent Office on the
24th July 1878.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
"AN IMPROVED METHOD OF AND MACHINERY
Southampton Buildings, London.
FOR GRINDING AND POLISHING GLASS." A communication from abroad by¨
Berthold Dukas, of Freiburg, Baden, Germany.
The object of this Invention is to provide means for superseding the method and
means hitherto practised for grinding or cutting table and other glass by substi-
tuting an improved method and improved automatic machinery therefor.
In order to grind or cut the facets upon the surface of glass ware the operator has
hitherto been accustomed to stem the glass against an iron disc, the grinding process
being performed by sand and water, together with the swift rotation of the disc. In
this method the damp dust of sand and glass is constantly thrown into the face of
the operator and great injury is caused to the health of the grinders. The produce
moreover is a very small one, because this mode of grinding necessitates great per-
sonal exertion and skill.
The grinder has to divide the circumference of the glass into as many equal parts
as there are facets to be cut upon the same, and therefore it seldom happens that
these facets are exactly regular; also the cut is more flat than concave.
My improved method and machinery for grinding glass ware performs the grinding
operation by means of a grinding stone of particular quality, or by an emery wheel,
without any preparatory treatment with sand. The work for the attendant or
operator is reduced to little more than feeding the glass to the machinery and
taking the same off when it is completely ground.

page_text: The glass is ground quite automatically, and one man can attend to 10 machines
at one time.
The produce of three skilled grinders hitherto has been about 100 glasses of
about 13 facets each per day, but by practising this Invention one man may turn
out 1000 glasses a day with 10 machines, or 30 times as much as a good band has
heretofore been able to do.
The work effected by my improved lathe or machine is mathematically precise,
whereas the result could never be quite exact by the hand work as heretofore
practised.
The glass leaves my improved lathe or machine in a state ready for immediate
polishing. The polishing may be effected by a similar lathe, only provided with a
polishing wheel instead of a grinding stone.
Figure 1 represents my improved machine in front elevation; Figure 2. is a plan
of the said machine; Figure 3 shews the same in side elevation; Figures 4, 5,
and 6 are detail views.
A modification of the said machine based upon the same principle is represented
upon Sheet 2, in which Figure 1a is a front elevation of the said modified construc-
tion Figure 2ª is a plan of the same; Figure 3ª, a side elevation of the same;
Figure 4a, a detail view.
The frame of the machine is carried by a bench or table, which, in the Drawings,
is partly shewn. Upon this bench or table are secured the two pillars A, A¹,
carrying suitable bearings for the horizontal shaft B, B¹, turning with its points in
the said bearings. Upon this shaft are mounted the grinding stone or emery
wheel S and the pulley or pulleys R, which receive a driving band from any prime
motor. In front of this grinding stone the grinding lathe is fixed upon the said bench or
table, the base plate F, F, Figure 1, being secured to the lathe or machine by means
of two set screws 1 entering from below through slots in the table, thereby allowing
the lathe to be adjusted in close proximity to or further from the stone as the
dimensions of the glass and the desired depth of cut_require.
Upon the base plate F, F', a circular plate G is mounted, turning round a vertical
spindle. This circular plate G is destined to give the glass its parallel or angular
position towards the grinding surface of the stone or wheel, and it is operated by
the endless screw D.
The circular plate G carries the support M, which slides in the direction toward
the stone S and backwards. The slide of the said support M carries the prism P, P¹,
upon which the two standards T, T¹, may be brought near to or withdrawn from
each other. This movement is imparted to the standard T¹ by means of a spindle
and the winch handle K¹. These parts constitute the main frame of the machine.
The glass which is to be ground is mounted between the two standards T, T¹, and
by means of the support M it is borne against the stone. The screw D, as before
mentioned, serves to adjust the side of the glass in the required parallel or angular
position to the grinding stone or wheel S.
In my other improved construction, shewn in Figure 1a, the prism P, P¹, with the
two, standards T, T', is mounted upon another prism U, U₁, carried by the
support M, M', which rests in the adjustable bearings F, F. The standard T may
be moved by hand upon the prism P when the set screw 2 is unscrewed, while the
standard T is operated by a spindle and a winch handle K¹. Fixed to the
standard T is the lock 4 which catches into the indentations of the partition
wheel T, h, thereby preventing the glass from turning during the grinding operation
of a facet. The prism P, P¹, may be turned upon the support M, M', and adjusted

page_text: upon the same by the screws D in order to adjust the cylindrical or conical side of
the glass against the grinding surface of the stone S.
I will now describe the automatic working mechanism of my said lathe or
machine under the three following divisions, that is to say,-
First. The means for mounting the glass.
Secondly. The mechanism for automatically bringing the glass against the stone,
and for withdrawing it at the required time.
Thirdly. The mechanism for turning the glass in the exact space and at the exact
time required.
The means for mounting the glass depend upon the various shapes of the glasses
to be ground. The wedges h, h¹, holding the glass accordingly will be preferably
made of cork, and of such a shape as to suit the glass. These wedges may be easily
exchanged for wedges of other shapes.
The foot of the glass is clamped by a concentric chuck C, C₁, C, as used in
turning lathes; the axis of every glass must be exactly the same as that of the
turning centres a, a'.
The mechanism for automatically bringing the glass against the stone, and for
withdrawing it at the exact time required is constructed as follows, that is to
say, the support M is mounted upon a horizontal screw E with a very quick thread;
one quarter of a turn of this screw is sufficient to bring the glass against the stone.
Upon this screw is mounted the small wheel & with any convenient number of teeth
or incisions, and the weighted lever H is loosely mounted upon the same screw E.
This lever carries two projections, through which passes the pawl i, Figure 2. A
spiral spring is coiled round this pawl between the two projections, and by the said
spring the pawl is pressed against the wheel d catching into its teeth. This wheel
being fixed upon the screw E, the pawl i when in gear, with the wheel & will turn
the screw E whenever the lever H rises or descends.
In Figure the weighted lever H is shewn in its lowest position. The support
M in this position has been pressed as closely as possible to the stone S, and the
latter has completely cut one facet of the glass. In order to cut or grind another
facet, it will be necessary to turn the glass the required distance of its circumference,
and to raise again the weighted lever.
I will now describe the automatic turning of the glass:-
The weighted lever.H is automatically raised by the following contrivance. Fixed
to the said lever H is the cam Z. At the side of the screw E of the support M is
fixed in the frame a pivot L, upon which is mounted the box N. This box carries
a rib t, a cam J, and a pulley O. A spiral spring coiled round the pivot L, con
tinually presses the box N with the cam and pulley towards the support M. The
pulley O receives its rotary motion by means of a small gear wheel V.
In Figure 1 is represented the position in which the cam J bears upon the cam
Z, thereby raising the lever H. When the said lever H has reached its highest
position, it is not allowed to drop suddenly, but will slowly glide down (by means
of the cam Z) on the back of the cam J, until the glass, which in the meantime has
been turned, is slightly pressed against the stone with another part of its surface.
As the pulley O rotates continuously, it would appear as if every turn of the said
pulley ought to again raise the lever H, which in the course of its descent causes
the glass to be ground. If such were the case, the grinding operation of one facet
would be dependent upon one revolution of the pulley O. It is necessary, however,
that this operation should in its duration depend alone upon the grinding power
of the stone or wheel S. The lever H accordingly must not be raised again until
it has reached its lowest position. For this purpose the following contrivance is
arranged to put the cams Z and J out of gear, that is to say, the back surface
of the cam J is formed in the shape of a spiral worm x, see Figure 4, against which
bears the pin n. As soon as the cam J has operated, it is, together with the pulley
O, pushed outward by the pin acting upon the worm x, and the cams J and Z
come out of gear. In this position the box N with the cam J and the pulley. O,

page_text: are maintained by the small lever falling behind the rib t. The pulley O and
cam J will thus remain out of gear with the lever H until the lever v be raised again.
This must be done whenever the lever H has arrived at its lowest position. The
lever H carries an arm or prolongation p projecting towards the pivot L. Whenever
the lever H arrives at its lowest position, the arm p by means of a pin lifts the
lever v ; the spring coiled around the pivot L acts upon the box N, and the cam
J comes again in gear with the cam Z, thus lifting the lever H. By each elevation
of the lever H the screw E is turned, and the support M carrying the glass is with-
drawn from the stone S, thus allowing the glass to be turned. The following
descent of the lever H brings the glass again against the stone.
When the desired number of facets has been cut upon the glass, the automatic
mechanism must be stopped, otherwise the first facet would again be borne against
the stone, and falling towards the same, the glass might easily be injured. This
stopping mechanism is arranged as follows, that is to say, below the screw
E is fixed a pivot 5, bearing a toothed wheel y with a cipher or figure to every
tooth beginning with 0 upwards. From the back of this disc y projects a pin 6
fixed behind number 1, see Figure 6. This pin bears against another pin 7, pro-
jecting from the pivot 5. A pawl w attached to the back of the cam Z, Figures
5 and 6, catches into the toothed disc y, turning the same by one tooth during
every descent of the lever H. This pawl being set into the respective indentation
of the disc, which bears the number of the facets required, the disc will be turned
as many times as the glass receives facets, and when the last facet is finished the
two pins 6 and 7 meet, and stop the lever H in its descent, where it is secured by
the pawl . The pulley O and cam J accordingly are prevented from coming again
in gear with the cam Z, and thus the grinding operation is stopped.
Instead of the mechanism above described, the following contrivance, shewn upon
Sheet 2, may be employed. The support M of the prisms U and P bears a down-
ward prolongation forming a hinge 8, which projects through the bench or table.
Into the said hinge 8 catches the adjustable excentric rod d projecting from the
excentric. The said excentric i has sufficient lift to bear the glass against the
stone if it be turned from the position, as indicated in Figure 3a, into the horizontal
line.
Upon the shaft E of the said excentric is mounted the weighted lever H. In
Figures 1, 2, 4, the said lever H is shown in its highest position. The prism P,
with the standards T, T¹, and the glass accordingly are removed from the stone in
their most backward position.
As herein-before described the lever H presses the glass against the stone during
its descent. When one facet is finished the glass must be withdrawn from the
stone in order to be turned, and accordingly the lever H must be raised again.
This is performed by a similar contrivance to that herein-before described. Upon
a box on the shaft E of the lever H is fixed the tooth z; behind the shaft E, and
parallel to the same, the pivot L is secured to the frame. Upon the pivot Lis
mounted the box N, bearing the rib.t, the cam J, and the pulley V', which are
pressed towards the frame by a spiral spring coiled around the pivot L. The
pulley V receives motion by a strap from the pulley V. To prevent the lever H
from being lifted by every revolution of the pulley V' a worm x is provided upon
the box N, a pin n acts against the said worm, the cams J and Z are pushed out of
gear and maintained in this position by a lever v falling behind a rib t exactly as
in the original construction. As soon as the lever H has reached its lowest, that
is to say, the horizontal position, the arm p lifts the small lever v, the cams J and Z
come again into gear and the lever H is lifted again.
The glass is automatically turned at the exact period required by the following
contrivanceUpon the back end of the box N on the pivot L, Figures 1, 4, 5, is
fixed a small arm k, which by each revolution of the pulley O lifts the adjustable
lever c, c¹, to a certain extent. The said lever c, c', is fixed upon a quadrangular
rod 1, 7, upon which another lever Q is mounted so as to glide along with the

page_text: standard T. The movement of the lever c, c¹, is imparted to the lever Q, and by
the latter to a third lever Q¹, to which a pawl q is attached for the purpose of
turning the toothed disc Th. This disc imparts to the glass its turning movement;
the said disc Th must have as many teeth as the glass is desired to receive facets.
The action of the pawl q is governed by the levers Q and Q', which are adjustable
by the adjusting screw b'; thus the toothed disc Th and with it the glass will be
turned by one tooth every time that the lever c, c', makes one lift.
During the descent of the lever H when the box N and the cam J are thrown
out of gear, the small arm k is also removed from the lever c, c', cousequently the
glass will never be turned during the grinding operation of the stone S, but only
at the exact period after the lever H has reached the lowest point and one facet
has been completed.
In my second improved construction Figures 1ª, 3ª, I have shewn another ar-
rangement for the automatic turning of the glass during every lift of the weighted
lever H. Fixed to the frame A¹ is a pivot r, connected by a shell fand a rod q
with the slotted plate Q, which oscillates on the centre e upon the standard T.
The plate Q bears the pawl, which catches into the teeth of the disc Th. When
the glass is moved against the stone S by the descent of the lever H. the pawl k
proceeds a little more upon the disc Th than the distance of one tooth..
The glass is turned during the backward motion of the support M, M'. The
pawl then will turn the disc Th by one tooth in the direction of the arrow.
The rod q may be adjusted within the shell fin order to exactly adjust the plate Q
and pawl when the prism P, P', has been turned by the screws D or the standards
T, T, have been displaced. The glass will follow the turning movement of the
disc Th, and its periphery will receive as many exactly equal facets as the disc Th
bears indentations.
The grinding operation with my said improved machine is effected in the
following manner, that is to say:-
First. The glass is mounted between the wedges h, h¹, by turning the handle K'.
Secondly. Upon the centre a' a partition disc Th is mounted with as many
teeth as the glass is destined to receive facets.
Thirdly. The base plate G is adjusted by the set screws 1 in the required distance
from the stone. In the second construction this adjustment is effected by the
excentric rod d.
Fourthly. The support M, M¹, is adjusted by the screw D in its required position
towards the grinding surface of the stone, according to whether the shape of the
glass is cylindrical or conical.
Fifthly. The pawl w is put into the tooth of the disc y, which bears the cipher
or figure representing the number of facets required. This cipher or figure must be
the same as the number of teeth of the disc Th. As soon as the two pins 6 and 7
no longer bear against each other the lever H will be raised again, and the machine
begins to grind.
As far as glasses of one and the, same shape are concerned only the first and
fifth operations are required to be effected by land for every single glass, all other
operations are performed automatically.
Having thus fully described the said Invention as communicated to me by my
foreign correspondent, and the manner of performing the same, I wish it understood
that I claim,
First. The method of grinding glass by means of grinding stones or emery
wheels without the preparatory treatment with sand, substantially as herein set
forth.
Second. The construction of a grinding and polishing lathe or machine com-
prising mechanism for the following operations, that is to say:-First, mounting
the glass; secondly, automatically bringing the glass against the grinding stone,
and for automatically withdrawing it from the same at the exact period required;

page_text: and thirdly, automatically turning the glass the exact space and at the exact period
required, all substantially as described and for the purpose set forth.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Seventeenth day of July, in the year of our Lord One
thousand eight hundred and seventy-eight.
TYTM DART T
W. RODT. LAKE. (L.S.)