Improvements in Machines for Grinding and Polishing Glass or other Material.
Year: 1898

page_text: Date of Application, 16th Dec., 1898-Accepted, 4th Feb., 1899
CUMIDITE SPECIFICATION.
Improvements in Machines for Grinding and Polishing Glass
or other Material.
I, FREDERICK FERDINAND FISCHER, Manufacturer, residing at 1103, Carnegie
Building, in the City of Pittsburg, County of Allegheny, State of Pennsylvania,
United States of America, do hereby declare the nature of this invention, and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
The object of my invention is to provide an improvement in grinding and
polishing machines; and to this end, my invention consists in a new and im-
proved machine for grinding or polishing glass, or other material, and in certain
combinations and features of construction all as hereinafter set forth.
In the accompanying drawings, Figure 1 is a plan view of a machine con-
structed in accordance with my invention; Fig. 2, a view of the same machine,
partly in elevation and partly in section; and Fig. 3, a section on the plane of
the line in Figures 1 and 2, but on a somewhat larger scale.
My invention provides means specially adapted for grinding and polishing
plate glass, although it may be employed on other material, either for grinding
or polishing. As shown in the drawings, I employ a rotary table, 1, on which
the material to be operated on is secured, and in combination therewith I employ
a beam, or carrier, 2, to which the runners, 3, or other rubbing devices are con-
nected and by which they are moved over the surface to be ground or polished
and which is given such a movement as to produce a complex relative movement
of the rubbing devices and of the material acted on, by which a very high degree
of efficiency is secured. This is an important feature of my invenion and has been
found in practice to produce improved results in the quality of the work done and
economical advantages in the time required in the way of hand labor during
the operation, and in the quantity and quality of the abrading material required
to do the work.
The important feature of my invention, by which the peculiar relative move-
ment of the rubbing surfaces is effected, is not confined to the employment of
either runners for grinding or buffers for polishing, which form separate parts of
the machine, but is applicable where the abrading surface is continuous and
formed on or secured to the beam, bar, or other structure by which the desired
movement is effected.
In accordance with my improvement, the table, 1, on which the glass or other
material is carried, is rotated continuously, and the beams, 2, and the runners 3,
are moved so that each point in them is moved in an arc of a circle with a re-
ciprocating motion. This movement of the beam is secured by connecting the
ends of the beams to the bell cranks, 4, and 4ª, which, as shown in the drawings,
are oscillated by the movement of a rod, 5, connected at one end to a rotating
disc, 6, driven from a main shaft, 7. In the drawings, two pairs of beams are
shown connected by pins, 8. to the bell cranks, 4, and 4", and the bell cranks, 4,
and 4, which are connected by a link, 9, are secured to and oscillate with the

page_text: shafts, 10, and 10ª, respectively. The opposite ends of the beams are connected
by pins, 12, to the levers, 11, and 11", which are mounted on vertical
shafts, 13, and 13. The rotating disc, 6, is fixed on a shaft, 14,
which is driven from the main shaft, 7, by the bevel gears, 15, and 15.
The table, 1, is adapted to be rotated from the main driving shaft, 7, and to be
raised to any extent necessary to bring it into the desired position for the per-
formance of the work, or lowered onto the truck, 16, when it is desired to remove
it from its position under the beams and runners. My invention provides new
and improved means by which the table may be raised and lowered and supported
in position, and means whereby the vertical movement of the table may be
effected without uncoupling the driving mechanism.
As shown in Figures 2 and 3, the lower side of the table is formed with a
flange, 17, which rests on a plate, 18, secured to the top of a vertical shaft, 19,
which is adapted to be moved up and down for the purpose of raising and lowering
the table, 1. The table is centred and held in position by projections, 20, on
the plate, 18, which may extend all the way around and form an annular flange,
if preferred. The lower end of the shaft, 19, extends downward through the
cylindrical opening in the cover, 21, of a casing, 22, which is kept filled with oil,
and which contains a worm gear, 23, 24, with a screw, 25, fitting into and passing
through a screw threaded opening in the worm wheel. The lower end of the
shaft, 19, rests on a head or cap, on the screw, 25, and the shaft, 19, is raised and
lowered by rotating the worm shaft, 26; and the worm wheel 24; the rotation
of the worm wheel in one direction or the other causing an upward or downward
movement of the screw, 25.
The bearings for the worm shaft, 26, in the casing, 22, are so formed as to
prevent the passage of oil therethrough and the interior of the casing is kept
filled with oil so that the parts are well lubricated.
A gear wheel, 27, is keyed to the shaft, 19, and meshes with a pinion, 28, on
a shaft, 29, having a bevel gear wheel, 30, secured thereon and meshing with
another bevel gear wheel, 31, on the main driving shaft 7. By means of this
construction, the shaft, 19, and the table, 1, are driven from the main shaft, 7,
but they may be driven, if preferred, by another shaft which receives its motion
from the same or from a different source of power from that which
actuates the shaft, 14, and the beam, 2. The important feature of the mechanism
for driving the shaft, 19, and table, 1, is the means by which the shaft is per-
mitted to move up and down without any uncoupling or disengaging of the
driving mechanism. For this purpose, the pinion, 28, which is keyed on the
shaft, 29, is of greater breadth than the gear wheel, 27, that is, the vertical
length of the teeth on the pinion is greater than the vertical length of
the teeth on the gear wheel, 27, so that the gear wheel, 27, and with it
the shaft, 19, and the table, may be moved vertically in either direction without
disengaging the teeth on the wheel and pinion, and consequently without any
danger of breaking any of the teeth.
In my improvement, the beams are operated from the main shaft, by means of
a construction which is comparatively simple and inexpensive; and the beams are
so connected with the actuating mechanism that each beam moves in a direction
opposite to and is balanced by the other beam of the same pair. This is an
important feature in large machines where the total weight of the beams and
runners, or buffers, is considerable, since it permits a much lighter construction
of the actuating mechanism than could be otherwise employed, and it is also of
importance on account of the action of the runners, or buffers on the glass, or
other material which is being operated upon, since the pull, or push on the glass,
or other material in one direction, by one of the beams, is counteracted by the
pull or push of the other beam of the same pair in the opposite direction, and
this is true not only of the longitudinal but also of the lateral movement of the
beams.
With my improved construction, the connecting rod, 5, the link, 9, the bell

page_text: cranks and levers at both ends of the beams, and the shafts, 10, 10°, 13, and 13ª
may be made comparatively light in construction and all are operated from the
vertical shaft, 14, without any such complication of mechanism as would be
required if the ends of the beams were given a complete circular motion. In
that case each beam would have to be driven separately, and would require to
be driven from each end, so that there would be at least twice as many rotating
shafts as there were beams, even if each beam were actuated by a separate motor,
and it is evident that they could not otherwise be actuated without greatly in-
creasing or complicating the gearing or intermediate driving mechanism. In
my improvement, the levers, 11, and 11ª, do not form part of the driving mechanism,
but merely act through their connections to guide the ends of the beams to which
they were connected."
The advantages of my improved construction, by which each point in the
beams, and in the runners, or buffers, is moved in an arc of a circle, consist not
merely in the features of construction referred to, but also in the improved
efficiency of the machine in the operation of grinding and polishing. If the
beams and the runners or buffers, be given a complete circular motion, while the
table is rotating, a part of the movement of the runners, or buffers, will be with
and a part against the movement of the table. When the runners or buffers
move in the same direction as the part of the table above which they were
placed, there is very little grinding or polishing effect; and, when they move in
a direction opposite to or nearly parallel to that in which the portion of the
table below moves, the effect is about the same as would be produced by two
oppositely reciprocating surfaces. It has been demonstrated in practice that
such a relative movement will not produce good results, and that it requires a
long time to produce even moderately good results. If the beams were given a
complete rotary movement, at their ends, the undesirable and inefficient relative
movements, referred to would occur when the ends of the beams were moving in
a direction tangent or or approximately tangent to the circles described by them,
and in my improvement these movements have been eliminated by limiting the
movement of the beams to a travel over an are of a circle whose chord is parallel
to, or approximately parallel to, the longitudinal axis of the beam, so that a
reciprocating movement of considerable amplitude is compounded with a
curvilinear movement by which the beam is at the same time given a compara-
tively small lateral movement. The result is that a highly efficient relative
movement of the rubbing surfaces is produced with a simple, inexpensive, and
well-balanced mechanism.
The combined lateral and reciprocating movement of the beams and runners,
or buffers, produced by my construction, in combination with the rotary move-
ment of the table, is found to produce a much better effect than a reciprocating
motion in a straight line, as it increases the complexity of the relative motion,
and prevents any lining or ruling effect on the surface to be ground or polished.
The alternate lateral movements of the runners and buffers toward and away
from one another and their curvilinear movement, all tend to produce a better
distribution and action of the sand or other abrading material than can be
obtained with a beam reciprocating in a straight line. If the beams were moved
in straight lines. they would require to be supported on rollers at both ends and
would require the employment of connecting rods for moving them.
The beams being supported on the levers, or bell cranks, 4, and 4ª, at one end,
and on the levers, 11, and 11", at their opposite ends, the employment of con-
necting rods, connected to their middle portions as usual, is unnecessary and
the beams being relieved of the weight and the thrust of the connecting rods are
not so liable to sag down in the middle.
Another advantage of my construction is that the beams are not liable to be
bent or buckled, as in some constructions, since they are driven from one end
only the levers, 11, and 11ª, acting as guides only. This undesirable effect
would be liable to occur in any construction where the two ends of the beams

page_text: were connected to and driven by cranks, whenever any adjustment of the bearings
became necessary.
In the construction shown in the drawings, the machine is provided with a
number of separate runners, 3, for grinding, which are connected to the beams, 2,
by bolts, 32, which permit a vertical movement of the runners, and the lower
portions of the runners, which rub on the surface to be ground, are formed of
projections, or stud-like parts, 33, with spaces between them through which the
sand, emery, or other abrading material may circulate. In order to prevent
turning of the runners, pins, 34, are fixed on the runners, and extend up through
holes in the flanges of the beams, 2.
Having now particularly described and ascertained the nature of my said in-
vention, and in what manner the same is to be performed, I declare that what I
claim is:-
1. In a grinding or polishing machine, the combination, with a rotary table,
of rubbing devices and means whereby a reciprocating curvilinear movement is
given to the rubbing devices.
2. In a grinding or polishing machine, the combination, with a rotary table,
of beams, bars, or carriers, for carrying grinding, or polishing devices, and means
for moving the ends of the beams, or bars, with a reciprocating curvilinear
movement.
3. In a grinding or polishing machine, the combination, with a rotary table,
of a pair of beams, or bars having their ends connected to cranks, or levers, by
which they are reciprocated in opposite directions in an are of a circle.
4. In a grinding or polishing machine, the combination, with a rotary table,
of two pairs of beams, or bars, for carrying rubbing devices, cranks, or levers,
to which the ends of the beams are connected, and connections by which both pairs
of beams are actuated from the same source of motion.
5. In a grinding or polishing machine, the combination, with a rotary table,
of a rotary shaft, two connected rock shafts, actuated from the rotary shaft,
oppositely placed cranks on the rock shafts, and beams connected to the cranks
and carrying rubbing devices which are moved in an arc of a circle.
6. In a grinding or polishing machine, the combination, with a rotary table,
of a rotary shaft adapted to move longitudinally in its bearings, a gear wheel
rigidly fixed on the shaft, and a pinion having teeth meshing with the teeth on
the gear wheel and so formed as to permit longitudinal movement of the shaft
while the gear wheel is engaged with the pinion.
7. In a grinding or polishing machine, the combination, with a rotary table,
of a rotary shaft, a screw threaded bolt or shaft forming a support for the rotary
shaft, worm wheel on the screw-threaded bolt or shaft, and a worm gearing with
the worm wheel and adapted by its rotation to turn the worm wheel and thereby
to raise or lower the rotary shaft.
8. In a grinding or polishing machine, the combination, with a rotary table,
of a longitudinally movable shaft in which the table is mounted, a driving
shaft, and toothed gearing between the driving shaft and the longitudinally
movable shaft which permits vertical movement of the table without disengaging
the gearing.
9. In a grinding or polishing machine, the combination, with a rotary table,
of a vertically movable shaft, a bearing therefor, a chamber for containing
material to lubricate the bearing, and a gearing in the chamber for raising and
lowering the shaft.
Dated at Pittsbure. Pennsylvania this 19th day of Novamba AD
1000