Year: 1888

page_text: I, SALVATORE BELLOTTI, of 80, Grays Inn Road, in the County of Middlesex,
Mechanical Engineer, 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 :—
My invention relates to machines for rubbing or grinding, flattening, surfacing
and polishing metal, marble, stone, wood, glass and other substances and for making
mouldings on substances such as marble and wood.
In carrying out my invention I employ a horizontal shaft to which motion is com-
municated from any suitable source of power; the said shaft carries a bevil wheel
which gears with a similar wheel on a vertical hollow spindle having a hollow spindle
in its interior. The latter spindle serves to receive a spindle carrying the tool or
holder of the rubbing, grinding, surfacing, flattening, or polishing material. The
spindles are provided with an adjustable spring arrangement whereby the pressure of
the tool upon the surface of the substance can be varied, and with a spring catch for
holding the tool in a raised position.
The first described hollow spindle is mounted in a support which is caused to slide
along a plate or bar by means of a screw threaded shaft working in the said support
and rotated alternately in right and left hand directions so as to move the tool from
one end of the machine to the other and back again.
If required a second screw threaded shaft can be provided parallel with that herein-
before described along which a support can be arranged to travel and carry moulding
tools for forming mouldings upon marble, wood and other substances.
The horizontal shaft and the gearing for operating the same are carried in travelling
bearings or supports which are moved alternately from one side to the other of the
machine by means of transverse screw threaded shafts.
I find it advantageous to give an intermittent motion to the screw threaded shaft
carrying the tool support in order to allow the tool to travel at an equal rate of speed
longitudinally and transversely.
This intermittent motion is communicated by a ratchet and a double acting pawl;
the ratchet is mounted on a shaft carrying a bevil wheel gearing with a similar wheel

page_text: on the said screw threaded shaft and the pawl has a reciprocating motion imparted to
it through a rod and a crank on one of the transverse screw threaded shafts.
In order to automatically reverse the direction of travel of the tools both longi-
tudinally and transversely when driving the machine by power and also to allow of
the tools working over any required portion of the surface of the substance, I mount
a longitudinal rod and a transverse rod sliding in bearings and carrying adjustable
clips and springs. The transverse rod carries at one end the shifting forks for the
.driving bands. A projection upon one of the travelling bearings or supports moves
along the transverso rod. I employ two fast pulleys one placed on each side of a
loose pulley and two bands for driving the shaft in opposite directions. By this
means when the said projection compresses the springs against the clips, the position
of which on the rod must have been previously adjusted, the rod is caused to move
suddenly and shift the driving bands so as to change the direction of rotation of the
transverse screw threaded shafts.
The longitudinal rod has one of its ends attached to a lever carrying a pin adapted
to change the direction of action of the double pawl when the lever is moved by the
said rod. A projection fixed to the tool holder support moves along the longitudinal
rod and, through the springs and clips on the rod, moves it in a similar inanner to that
herein before described when referring to the transverse rod, thereby moving the lever
with its pin and changing the position of the pawl.
In order to enable my invention to be fully understood I will proceed to describe
how it can be carried into practice by reference to the accompanying drawings in
which
Figure 1 is a plan.
Figure 2 is a side elevation and
Figure 3 is an end elevation partly in section of a grinding and polishing machine
constructed according to my invention and arranged to be driven by power.
Figure 4 is a vertical section drawn to an enlarged scale of the hollow spindles and
tool-spindle.
Similar letters in all the figures indicate similar parts.
a is the horizontal shaft to which motion is advantageously communicated by means
of a bevil wheel thereon gearing with a similar wheel on a shaft d carrying a
pinion e which engages with a cog wheel on the shaft of the driving pulleys.
g is the bevil wheel on the shaft a which gears with a similar wheel h mounted on
the vertical hollow spindle i, the wheel g being arranged to rotate with the shaft a and
to slide thereon.
jis the hollow spindle in the interior of the spindle i and which receives the spindle k
carrying the tool or holder of the rubbing, grinding, surfacing, flattening or polishing
material.
m, figure 4, is the spring for producing the required pressure of the tool upon the
surface of the substance under treatment. The spring m is compressed between the
spindle and a collar on a screw threaded rod o which can move vertically but is
prevented from rotating by pins (one of which is shown at p) fixed to the collar n and
working in vertical slots (one of which is shewn at y) in the hollow spindle j. The
screw threaded rod o is operated by means of a nut the top of which projects above
the spindle so as to allow of its being turned by the aid of a spanner or the like,
and by this means the spring m can be compressed to a greater or less extent so as to
vary the pressure of the tool to suit the substance upon which it is to operate. The
nut is held from moving vertically by a ring s fixed to the spindle and fitted in a
groove in the nut.
The spindle can be slid within the spindle in order to adjust their length and they
are then fixed together by tightening a clamping ring by means of a pressure
screw u, the spindle i being split at for this purpose.
w is, the spring-catch for holding the tool in a raised position for allowing the
substance to be conveniently placed or removed from under the tool or for other
purposes. The spring catch is adapted to engage with a catch a fitted in a key y
which is passed through the spindle and through a slot in the tool-spindle k, the

page_text: slot and key y allowing the tool-spindle to slide within the spindle j to a limited
extent. It will be seen that by pressing the tool-spindle upwards the catches wand.c
will engage with each other and retain the tool in its raised position and, by simply
pulling the catch to outwards, the tool will descend onto the substance to be operated
upon.
a¹ is the support in which the spindle i is mounted and 61 is the bar along which the
support a is caused to slide by means of the screw threaded shaft c' working in the
support a and rotated alternately in right and left hand directions by the means
hereinafter described so as to move the tool from one end of the machine to the other
and back again.
d is the second screw threaded shaft which I sometimes employ in addition to the
shaft cand placed parallel thereto along which shaft d¹n support (not shewn in the
drawing) can be arranged to travel in a similar manner to the support a' and carry
suitable moulding tools for forming mouldings upon marble, wood and other substances
as will be well understood without further description. The scrow threaded shaft d'
is conveniently driven by a bovil wheel e¹ thereon gearing with a similar wheel f¹
on the screw threaded shaft ¹ of tho driving pulleys and which are hereinafter
described.
g and h¹ are the travelling bearings carrying the horizontal shaft a and the bevil
wheels b and c operating the saine.
is the transverse screw-threaded shaft for moving the bearing gl alternately from
one side to the other of the machine, the bearing being similarly operated by a liko
shaft (not shown in the drawing) situated at the opposite end of the machine and
driven through the bevil wheels e, and a bevil wheel j' on the opposite end of the
shaft gearing with a bevil wheel mounted on the latter transverse screw-threaded
shaft.
is the ratchet and m' the double acting pawl for giving an intermittent motion to
the screw-threaded shaft c¹.
n is the shaft on which the ratchet is mounted, o' is the bevil wheel on the
shaft n', for imparting motion to the screw-threaded shaft c' by gearing with a bevil
wheel p mounted thereon.
The shafts n' and c¹, and gearing o' and p₁ are mounted in the travelling bearing gl
and the bevil wheels cand o are arranged to slide on their respective shafts & and n¹
and to be rotated by them.
The pawl m¹ is carried by an oscillating arm g' mounted loosely on the end of the
shaft . To this arm is jointed the connecting rod which is operated by the
crank s on the screw-threaded shaft so that as the latter shaft is revolved by
the driving pulleys the pawl m³ is reciprocated thereby driving the shafts n¹ and c¹
intermittently. By this means the tool is caused to move longitudinally and trans-
versely at an equal rate of speed.
is the longitudinal rod and u' is the transverse rod by means of which, in com-
bination with the mechanism hereinafter described, the direction of travel of the tools 1,
both longitudinally and transversely is automatically reversed and the tool is allowed
to work over any required portion of the surface of the substance.
vand o are the bearings in which the rod t is adapted to slide, the said bearings
being formed in projections, which will be presently referred to, on the support a¹ and
travelling bearing
respectively.
and y are the bearings in which the rod u slides and which are fixed to the
frame of the machine.
2, a are the clips and 62, c² are the springs on the rod t¹.
d, are the clips and f², 9 are the springs on the rod u¹.
The clips, a², d, are provided with pressure screws to allow of their being fixed
on their rods to any position into which they have been moved.
Spring bolts p², 92 are provided in the bearings w² and y' respectively, their ends
engaging in depressions in the rods t' and u¹ respectivoly for the purpose hereinafter
described.
² and are the shifting forks for the driving bands and k² respectively, the said

page_text: forks being fixed on the end of the rod u. The band is twisted as shown in figure 2
so as to drive the shaft alternately in reverse directions.
-is-tho-projection formed upon the travelling bearing gl and moving along the
rod u¹.
m² and n² are the two fast pulleys one placed on each side of the loose pulley o²
on the screw-threaded shaft i'."
As the projection 12 moves along the rod it will compress one or other of the
springs, gagainst its clip until the pressure becomes sufficient to force the spring
boll up out of its depression in the rod when the rod will quickly move under
the action of the spring and will shift the driving bands and so as to change the
direction of rotation of the screw-threaded shaft and of the corresponding shaft at
the other end of the machine.
The loose pulley o² is formed in independent parts, as shown in figure 3, to facilitato
the shifting of the driving bands.
2, 2, 2 indicate the lever carrying the pin 7ª for changing the direction of action
of the double pawl.
The lever consists of a rod ² to which one end of the longitudinal rod t¹ is loosely
attached by an eye 2 so as to admit of the rod sliding therein; the rod is carried
by arms s², mounted loosely on the shaft d and carries a rod t to which the pin u
is fixed; the rod t is pivotted at w².
is the projection fixed to the tool-holder support a¹ and which moves along the
rod and through the springs 62, c2, clips 2, a and spring bolt p² moves it in a
similar manner to that in which the rod u is moved.
It will be seen by referring to figure 2 that when the rod t¹ is moved it will move
the rods and t², and the pin u² which is situated between the two arms of the double
acting pawl m will raise the arm which is in engagement with the ratchet out
therefrom, and the other arm will then be in engagement with the ratchet and the
latter will rotate in the opposite direction thereby changing the direction of rotation
of the shafts n' and c¹.
The operation of the machine is as follows:-
The material to be ground, polished or otherwise treated is placed in position on the
base A of the machine, the tool is adjusted in the manner hereinbefore described to
suit the thickness of the substance and to work with the required pressure, the
clips, a³, d, e are moved to and fixed in the required position on their rods ', u' so
as to limit the range of the tool to the extent of surface over which it is desired to
act and the machine is then set in motion.
The tool will revolve and press upon the said substance and will be moved longi-
tudinally and transversely over the whole surface of the same or any portion thereof,
and by shifting the position of the clips at any time the action of the tools can be
confined to any required portion of the surface.
Although for convenience of description 1 have hitherto referred to one tool only, I
have shewn two of such tools adapted to the machine in order to illustrate how this
can be done; it is evident however that no description is necessary to enable this to
be understood.
If it is required to cause the tool to travel longitudinally over the surface of the
substance under treatinent at a greater rate of speed than would be imparted by the
ratchet and click, I remove the said ratchet and click and drive the shaft n¹ by means
of gearing from the shaft d, and 1 replace the screw-threaded shaft c' by a shaft having
two quick screw-threads crossing each other so as to give a more rapid movement to
the support a' and effect its return movement.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is
1. In a grinding and polishing machine the use of a rotating tool for holding the
grinding or polishing material provided with an adjustable spring arrangement and
with a spring catch operating for the purposes and substantially as set forth.

page_text: 2. In a grinding and polishing machine the arrangement of mechanism whereby
the rotating tool is caused to move simultaneously in longitudinal and transverse
directions substantially as set forth.
3. In a grinding and polishing machine the arrangement of mechanism for auto-
matically causing the longitudinal and transverse return movement of the rotating
tool and adjusting the range of operation of the tool, substantially as set forth.
4. In a grinding and polishing machine the arrangement of mechanism for giving
an intermittent motion to the screw-threaded shaft carrying the tool support operating
for the purpose and substantially as set forth.
5. The combination of parts forming the improved grinding and polishing machine
substantially as hereinbefore described and illustrated in the accompanying drawings.
Dated the 13th day of March 1888.
G. F. REDFERN & Co.,
4, South Street, Finsbury, London,
Agents for the Applicant.