Year: 1899

page_text: arranged for simultaneous action upon opposite sides of the plate glass placed
between them, and mechanism for simultaneously oscillating the grinding wheels
in reverse directions, as and for the purpose set forth.
6. In apparatus for grinding and polishing plate glass, a countershaft, longitu-
dinally alined shafts provided at their inner ends with grinding wheels, hangers
carrying the said shafts and mounted co-axially with the countershaft, means for
imparting movement to the grinding wheels from the countershaft in reverso
directions, and means for imparting an. oscillatory movement to the hangers, as
and for the purpose set forth.
7. In apparatus for grinding and polishing plate glass, a countershaft, hangers
mounted co-axially with the countershaft, grinding wheels, shafts mounted in the
free ends of the hangers and having the grinding wheels applied thereto, means
for driving said shafts in reverse directions from the countershaft, and a shaft
provided with oppositely extending crank portions having connection with the
grinding wheel shafts, the parts being combined and arranged for operation in the
manner and for the purpose specified.
8. In apparatus for grinding and polishing plate glass, a shaft mounted for
rotary and sliding movements and bearing a grinding wheel, a set screw having
its inner end portion operatively connected with the adjacent terminal portion of
the shaft, a spring disposed to normally move the shaft to cause the grinding
wheel to bear against the surface to be operated upon, and a connection between
the set screw and shaft for moving the latter outward against the tension of the
aforesaid spring, substantially as set forth.
9. In apparatus for grinding and polishing plate glass, a shaft mounted for
rotary and sliding movements and bearing a grinding device, a set screw, a
spring normally exerting a pressure to hold the grinding device in working rela-
tion, and a frame having loose connection with the said shaft and set screw and
adapted to move the shaft against the tension of the aforementioned spring when
backing the set screw, as and for the purpose set forth.
10. In combination, a hanger, a shaft rotatably and slidably mounted in the
hanger and provided with a grinding device, a relatively fixed bearing, a set
screw threaded in said bearing and operatively connected with the adjacent end of
said shaft, collars or stops applied to the set screw and shaft, a spring interposed
between the fixed bearing and the collar applied to the shaft, and a frame having
loose connection with the set screw and shaft and adapted to engage with the
collars thereof, as and for the purpose set forth.
Dated this 24th day of November 1899
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.

page_text: vertical clamp bars 26 parallel with the clamp bars 25 and set in therefrom a
short distance. The plate glass to be operated upon is held between the bars 23,
24 and 26 and is simultaneously ground and polished upon both sides by means
of the grinding wheels, the latter receiving a combined rotary and oscillatory
movement, the latter movement obviating the formation of rings and hollow
grinding of the glass and ensuring flat surfaces. Adjacent to and in advance of
the removable clamp bar 25 is located a stand e supporting a roller d in a hori-
zontal position, said roller being of wood and clothed with rubber or leather
so as to obviate injurious contact of the plate glass therewith when placing the
plate glass in position or removing it from the machine. The upper surface of
the roller d is about in the plane of the top edge of the bar 23 and this roller
constitutes a rotary support for the plate glass when sliding over the bar 23 into
or out of position.
The swinging frames are mounted upon the countershaft, thereby resulting in
simplicity and compactness of arrangement and preventing any variation between
the axis of the countershaft and the shafts 5 in the various stages of movement
of said shafts 5 due to the oscillation of the swinging frames. The mounting of
the operating parts so as to effect a reverse movement of the grinding wheels both
as regards rotary and reciprocating movements results in a neutralization of the
forces upon opposite sides of the plate, whereby it is not necessary to make the
holder for the glass exceedingly heavy and to provide a firm carriage in order
to prevent creeping or movement of the glass from between the grinding wheels
when the machine is in operation as would be the case if the grinding wheels.
rotated in the same direction and oscillated in the same direction. The abrading
material such as sand and water are fed to the grinding wheels and plate from a
hopper 27 located above the grinding mechanism and having its bottom perforated
at intervals for the escape of the sand and water.
Within the spirit of the invention the grinding wheels may have any form and.
the working parts may be mounted in any substantial manner, hence it is to be
understood that in constructing and installing an apparatus constructed in accord-
ance with this invention various changes in the form, proportion and minor details.
of construction may be resorted to without departing from the spirit of the
invention.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is :-
1. In a machine for grinding and polishing plate glass, a pair of vertically
disposed grinding wheels spaced apart, means for rotating the grinding wheels
in reverse directions, mechanism for separating and bringing the grinding wheels
together, and a feeder for supplying an abrading material between the grinding
wheels, substantially as set forth.
2. The combination with a pair of grinding wheels spaced apart and vertically
arranged, and independent actuating mechanism. therefor, of a holder located
in the space formed between the grinding wheels and comprising adjustable and
detachable bars for confining between them the plate glass to be operated upon,
substantially as described.
3. The combination with a pair of vertically arranged grinding wheels spaced
apart, and actuating mechanism therefor, of a holder located in the space formed
between the grinding wheels, and a horizontally disposed roller at one end of the
lower bar of the holder forming a rotary support for the plate glass when slipping
it between or removing it from the grinding wheels, substantially as described.
4. In apparatus for grinding and polishing plate glass, a pair of grinding
wheels located for simultaneous action upon opposite sides of the plate glass
between them, and means for imparting a simultaneous oscillatory movement to
the grinding wheels, as and for the purpose set forth.
5. In apparatus for grinding and polishing plate glass, a pair of grinding wheels

page_text: applied to the inner faces of the grinding wheels and may consist of metallic
blocks or buffers according as to whether the glass plate is to be ground or
polished. The abrading devices a are oblong and radially disposed and are
secured to the grinding wheels by bolts or like fastenings passing through open-
ings formed in the ears b integral with the parts a. The sides of the rubbers are
beveled so as to direct the sand and water between the glass and the outer faces
of the rubbers.
Each of the shafts 5 is mounted in the lower ends of hangers 10 suspended
co-axially with the countershaft 2 and preferably mounted thereon for swinging
movement. The hangers 10 are spaced apart and are connected by means of a
brace 11 of approximately X form. The end portions of the brace 11 are bolted or
otherwise secured to the upper and lower ends, respectively, of corresponding
hangers 10, whereby said hangers move in unison and with the brace constitute
a swinging frame which supports the grinding mechanism. Oscillatory movement
is imparted to the swinging frames in an automatic and positive manner and in
reverse directions so that when one of the shafts 5 moves forward the other moves
rearward, which is of material advantage in equalizing the strain and effecting
the best results.
In order to impart a reverse oscillatory movement to the swinging frames the
shaft 12 is provided and is formed with oppositely. disposed crank portions 13
which are connected by links 14 with the respective shafts 5. The shaft 12 is
driven from any moving part of the machine and for convenience is provided with
a band pulley 15 which is connected by a drive belt with a corresponding
pulley 16 on the countershaft 2. The pulley 15 is of larger diameter compared
with the pulley 16, whereby the shaft 12 is rotated at a low speed, which is desir-
able so as not to oscillate the swinging frames too rapidly.
A bracket 17 is secured to the lower end of the extreme hangers 10 of the
swinging frames and its lower end is formed with a threaded opening in line with
the shaft 5 and is adapted to receive a set screw 18 whose inner end portion enters
an opening in the outer end of the adjacent shaft 5. A collar or stop 19 is pro-
vided at the outer ond of the set screw and is adapted to engage with the inner
side of the outer cross bar of a slidably mounted frame 20, the inner end of the
hub of the hand wheel of the set screw engaging with the outer side of said cross
bar, whereby a movement of the set screw in either direction effects a correspond-
ing movement of the frame 20. A collar 21 is applied to the outer end portion
of each shaft 5 and is adapted to engage with the inner side of the inner end
of the cross bar of the frame 20 and receives the end thrust of a spring 22 of the
coil type interposed between said collar 21 and the bracket 17. This spring 22
surrounds the inner end portion of the set screw and the outer end portion of
the shaft 5 and normally exerts a pressure to move the shaft 5 inward and force
the grinding wheel against the side of the plate glass in position to be ground or
polished. The slidable frame 20 is of rectangular and oblong form and its outer
cross bar is apertured to admit of the set screw 18 passing therethrough and its
inner cross bar is correspondingly apertured to receive the outer end portion of
the shaft 5 which is adapted to rotate freely therein. When it is required to move
the grinding wheel outward for any purpose such as to admit of the plate glass
being placed in position for operation or removed after being polished or to admit
of the buffers being properly adjusted or substituted, it is only necessary to rotate
the set screw to effect an outward movement thereof when its collar 19 bearing
against the outer cross bar of the frame will cause the latter to move outward
and draw the shaft 5 outward by reason of the inner cross bar of the frame
engaging with the collar 21. When the plate glass is in position the set screw
is moved inward thereby permitting the spring 22 to react and move the shaft 5
inward and force the grinding wheel against the side of the plate to be ground
and polished.
The plate glass holder is located in the space formed between the opposing
surfaces of the grinding wheels and consists of a lower bar 23, an upper bar 24,

page_text: Date of Application, 24th Nov., 1899--Accepted, 27th Jan., 1900
COMPLETE SPECIFICATION.
Machine for Grinding and Polishing Plate Glass.
We, MASON RASH WELTY and GEORGE SPARKS RUMBAUGH, Gentlemen, residing
respectively at Hunkers and Greensburg, in the County of Westmoreland, in
the State of Pennsylvania, one of the 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:-
This invention has for its object to devise a machine for grinding both sides
of plate glass evenly and smoothly at one operation and to obviate the formation
of rings and hollow grinding which are objectionable features commonly met
with in the operation of machines as generally constructed, said machine being.
likewise adapted for polishing by changing the rubbers and substituting a polish-
ing compound for the grinding material.
A further purpose of the invention is to facilitate access to the active or abrad
ing surfaces of the grinding wheels for repairs and to enable a substitution of
rubbers, the grinding wheels being advanced automatically as the work of grind-
ing progresses.
A still further purpose of the invention is to combine with the grinding wheels
means for imparting an oscillating motion thereto, said means being automatic
in operation.
Various other advantages will suggest themselves as the nature and details of
the invention are comprehended and to this end and to a full knowledge of the
structural features reference is to be had to the following description and draw-
ings hereto attached, in which:
Fig. 1 is a front view of a machine constructed in accordance with and embody-
ing the essential features of the invention.
Fig. 2 is a top plan view.
Fig. 3 is a central longitudinal section.
Fig. 4 is a sectional detail of the means and mountings for the outer end of
the shaft gearing and grinding wheel.
Corresponding and like parts are referred to in the following description and
indicated in all the views of the drawings by the same reference characters.
The frame work for supporting the operating parts may be of any desired for-
mation, the several beams being connected together in any substantial manner.
The frame work represented by the numeral may be of a portable character
or may be the interior structure of a building according to the location and
manner of mounting the operating parts. The countershaft 2, which is driven
from a suitable source of power, is provided with pulleys 3 and 4, and shafts 5
in longitudinal alinement are provided with pulleys 6 which are connected by
belts 7 and 8 with the respective pulleys 3 and 4, the belt 7 being cross and the
belt 8 open, whereby the shafts 5 are driven in reverse directions.
The grinding wheels 9 are secured to the inner or opposing ends of the shafts 5-
and are rotated in opposite directions. Each grinding wheel comprises a hub,
concentric rings and spokes or radial arms. Abrading devices are detachably