Improvements in or relating to Grinding or Pulverizing Machines.
Year: 1898

page_text: Date of Application, 23rd June, 1898-Accepted, 17th Sept., 1898
COMPLETE SPECIFICATION.
Improvements in or relating to Grinding or Pulverizing Machines.
I, JOHN CALHOUN CLARK, of No. 182, Peachtree Street, in the City of Atlanta,
County of Fulton, and State of Georgia, United States of America, Manufacturer,
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:―
In that class of grinding mills in which one or more grinding rolls are carried
in a circle and revolve within a grinding ring, the supporting of the rotary roll
shafts has been attended with difficulties incident to the access of dust to the
bearings, the wearing and heating of the latter and of the journals, and the
attendant delays and expense for repairs and the waste and expense of lubrica-
ting materials. To obviate these objections I have devised a form of bearing
as fully set forth hereinafter and as illustrated in the accompanying drawings,
in which:
Fig. 1 is a perspective view of a grinding mill embodying the invention, parts
being broken away to more clearly illustrate the arrangement of the grinding
rolls and pan; Fig. 2 is a vertical sectional view of a journal box of one of the
grinding roll shafts, the shaft being broken away.
The general arrangement of the mill is illustrated in Fig. 1 in which A repre-
sents the mortar, consisting of a pan, 1, within an exterior casing, 5, with inter-
vening passages, 6, for the downward passage of the material which has been
ground and which has been thrown up against and passes through a screen 15,
inclosed by a cover.
The mortar, A, is suspended within a base plate, B, on which is erected a
frame, consisting of a suitable number of standards, 18, curved to meet at a
central hub, 19, in which is the upper bearing of a driving shaft, 20, provided
with a band wheel, 23*.
The lower bearing of the shaft, 20, is in a hub, 22, at the meeting point of
radial arms, 21, extending to the standards, 18. The shaft, 20, extends downward
through the hub, 22, and carries a carrier disk, 25, which turns within a ring, 14,
supported by the standards, 18, and constituting with the disk the cover of the
grinding chamber.
Within openings in the carrier disk are suspended by suitable trunnions a
number of boxes, C, containing the bearings of the upper ends of shafts, 30, to
the lower ends of which are suitably secured the grinding rolls, 31 arranged
within a grinding ring, 3, supported within and above the bottom of the
basin 1.
As thus supported the rotation of the driving shaft and its disk will cause
the rolls to fly outward, the boxes rocking on their trunnions, until the rolls
travel on the face of the ring grinding against the latter any material which is
thrown upward between the rollers and ring by the forward travel of the rolls
which thus elevates the material.

page_text: The rollers may be secured to the shafts by many-sided nuts, which as they
rotate stir up the mass of material into which they project, thus preventing it
from packing at the bottom of the basin Near the upper end of each roller
shaft, 30, is a collar, 23, so that a section, 24, of the shaft projects above the
collar, the box, C, being divided into two sections adjacent to said collar each
provided with a flange, 27, and the flanges being secured together by bolts, 28.
Within the lower section of the box, C, is a bearing sleeve or brass, D, preferably
having at the upper end a flange, 29, resting on a shoulder, w, of the box, and
receiving the collar, 23, which thus rests on the upper end of the brass, while the
body of the shaft below the collar has its bearing within the brass.
Heretofore where the shaft terminated at the top of the collar, 23, there was
great wear of the under face of the collar, and within the brass this wear was
uneven and the under face of the collar became rounded. As a consequence
of the friction much oil was required while the heating of the bearings occa-
sioned delays. These objections have all been overcome by extending the shaft
above the collar, forming a projecting part, 24, and providing a separate brass
or sleeve, 26, for this portion, this brass fitting within the upper part of the
box, C, as shown.
In the box are two lubricating chambers X and Y, and preferably each is
provided with a narrow opening or so that only a limited quantity of lubri
cant can rest at one time upon the surface to be lubricated. The opening may
be in the bottom of the chamber X, or as shown in the top of the brass, 26, while the
opening is directly above the sleeve, 23, at one side of the same. By thus
confining the portion of lubricant in direct contact with the bearing to a limited
amount I avoid agitating and heating the whole body, and I have found that
by this arrangement of bearings and lubricating means I have reduced the
amount of lubricant required seventy-five per cent. Further, I have found that
there is practically no heating of the bearings; dust is completely excluded;
there is no unequal wear of the parts, and the machine runs with less power and
less interruption for repairs.
Each chamber may be filled through an opening closed by a plug, 33. When
access to the interior of the bearing is required, it can be had by unbolting the
flanges 27, 27, and removing the upper sections of the box and bearing.
The lower part of the box is constructed in any suitable manner; as shown it
has a packing, 10, confined by a screw gland, 11. It will be evident that the
bearing for the upper end of the shaft, 20, may be constructed like those of
the shafts, 30.
Having now particularly described and'ascertained the nature of the said
invention and in what manner the same is to be performed, I declare that what
I claim is:-
1st. The combination with the mortar, revolving shaft and rollers, shafts and
boxes carried by said shaft, of a frame having converging standards supporting
the shaft bearings, substantially as set forth.
2nd. The combination of the base plate, B, and converging standards, 18,
of the shaft 20, disk, boxes, shafts and rollers carried by the said shaft, the mortar
supported by the base and ring, 14, and arms, 21, supported by the standards,
substantially as described.
3rd. The combination with a shaft having a collar below its end, of a box in-
closing the end of the shaft, a brass fitted within the box below said collar, and
a second brass fitted within the box above the collar, substantially as described.
4th. The combination with a shaft having a collar below its end, of a box
inclosing the end of the shaft, a brass fitted within the box below said collar,
and a second brass fitted within the box above the collar, oil chambers within the
box one with an opening leading to the collar and the other with an opening
leading to the upper brass, substantially as described.
5

page_text: 5th. The combination of the shaft, its collar below the end, a box and brass
fitting the shaft below the collar, a brass fitting the upper end of the shaft,
lubricating chambers and contracted openings between the latter and the bear-
ings, substantially as described.
6th. The combination of the shaft, collar, brass D having a flange, 29, brass, 26,
having a closed end with an opening, r, and box with lubricating chambers
enclosing said shaft and bearings, substantially as described.
7th. The combination of the shaft, collar, brass D having a flange, 29, brass 26
having a closed end with an opening 7, and box with lubricating chambers en-
closing said shaft and bearings and consisting of two connected parts, substan-
tially as described.
8th. The combination of the shaft, collar, brass D having a flange, 29, brass, 26,
having a closed end with an opening, x, and box with lubricating chambers
enclosing said shaft and bearings, and packing at the lower end of the box,
substantially as described.
9th. The combination in a grinding mill of the shaft collar, brass 26 having
a closed end with an opening, and box provided with trunnions and with
lubricating chambers enclosing said shaft and bearings, substantially as described.
Dated this 23rd day of June 1898.
BOULT & WADE,
Agents for the Applicant.