Improvements in Roller Mills.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in Roller Mills.
I, ARTHUR MAURICE ROBINSON, of Railway Works, Rochdale, in the County
of Lancaster, Engineer, do hereby declare the nature of this invention to be as
follows:-
The object of this invention is to provide roller mills which shall be efficient
in grinding or crushing, have very regular or equal feed, in some cases dispense
with the use of a feed board, occupy small space, and afford greater facility for
inspection, during operation, of the grain or other material being ground or
crushed.
For the above purposes I form one of each pair of rollers larger in diameter
than the other so as to obtain different surface speeds of the two rollers when
they are both driven at about the same number of revolutions. The differential
surface speed ensures efficient grinding or crushing. I also arrange one roller of
each pair, preferably the smaller roller, higher than the other roller thereby
ensuring a considerable saving of space. The grain or other material coming
from the feed tray is projected against the roller which acts as a movable feed
board and ensures a very regular feed and also allows of the usual stationary
feed board being dispensed with thereby allowing the state of the feed between
the rollers being readily seen. Underneath the higher roller there is a space
through which the crushed material passing the rollers can be examined.
Dated this Sixth day of August 1897.
I, ARTHUR MAURICE ROBINSON, of Railway Works, Rochdale, in the County
of Lancaster, Engineer, do hereby declare the nature of this invention and. in
what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement, reference being had to the accom-
panying drawing :-
The object of this invention is to provide roller mills which shall be efficient
in grinding or crushing, have very regular or equal feed, in some cases dispense
with the use of a feed board, occupy small space, and afford greater facility for
inspection during operation of the grain or other material being ground or
crushed

page_text: For the above purposes I form one of each pair of rollers larger in diameter
than the other so as to obtain different surface speeds of the two rollers when
they are both driven at about the same number of revolutions. The differential
surface speed ensures efficient grinding or crushing. I also arrange one roller of
each pair, preferably the smaller roller, higher than the other roller, thereby
ensuring a considerable saving of space. The grain or other material coming
from the feed tray is projected against the roller which acts as a guiding plate
or movable feed board, and ensures a very regular feed, and also allows of the
asual stationary feed board being dispensed with, thereby allowing the state
of the feed between the rollers being readily seen. Underneath the higher
roller there is a space through which the crushed material passing the rollers
can be examined.
The drawing herewith is a vertical section of a roller mill, illustrative of my
improvements. a a¹ are the rollers, between each pair of which the material
to be crushed or ground passes, as shewn. The rollers a are of larger diameter
than the rollers a¹ so that when the rollers are driven at equal revolutions the
surface speeds are different. The axes of the rollers a¹ are arranged at a higher
level than those of the rollers a so that a line joining the axes is at an angle
inclined to the horizon thereby enabling a shorter framework and casing b to
be used. c is any usual feed apparatus for feeding the material to the rollers.
The material on leaving the feed apparatus c falls on to the large rollers a which
act as movable or spreading feed boards so as to spread out the material evenly
and regularly in a thin stream before it reaches the point d between the rollers.
This and the more efficient grinding action of the larger diameter rollers prevents
any accumulation of material at the point d which occurs in all ordinary types
of roller mills, this accumulation causing the material to pass through the rollers
at intervals in excessive quantities thus causing the material to be flaked instead
of being properly ground. By feeding the material on to the rollers a the usual
stationary guide plates or feed boards are also dispensed with, thus allowing the
state of feed to be readily observed through the doors e. By making the rollers a
of larger diameter the temperature of the surface of such rollers and the material
in contact therewith is kept lower than when small rollers are used run at higher
speeds this lower temperature ensuring a better bite or grip of the rollers on
the material so as to carry it regularly between the rollers. By reason also of
the rollers a¹ being at a higher level than the rollers a the ground material
leaving the rollers can be more easily observed through the openings f provided
with doors f. The framework, bearings, gearing etc. of the mill are of any
usual or convenient construction.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed I declare that what
I claim is:
First. Roller mills having one of each pair of rollers of different diameter to
the other of the pair and so arranged that the plane of the axes of each pair is at
an angle inclined to the horizon substantially as and for the purposes set forth.
Second. Feeding material to be ground on to one of each pair of rollers of a
roller mill when the plane of the axes of each pair is at an angle inclined to the
horizon substantially as and for the purposes set forth.
D