Year: 1889

page_text: Date of Application, 23rd Feb.. 1889
Specification Accepted, 23rd Mar., 1889
I, EDWARD PRIME, of Barrington, Cambridgeshire, Manufacturer, do hereby
declare the nature of the said 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 relates to improved apparatus for grinding cement and analogous
materials.
The improved, apparatus is illustrated on the accompanying drawings in elevation
partly in section in Fig. 1. and in plan view partly in section in Fig. 2.
The improved apparatus is constructed with a suitable foundation or base plate, 3,
to which are bolted opposite standards, 4, which are bolted to and support a cross
head, 5. The base plate, 3, standards, 4, and crosshead, 5, may be of any suitable.
formation.
From the base plate there also arises a contre boss or support, 6, acting as a
footstep to a short centre shaft, 7, depending from the centre of the pan, 8, and which
enters the said footstep and thus centres and supports the pan. The pan is also.
supported by a series of any suitable number of rollers, 9, which are supported in
suitable bearings, 10, bolted to the base plate; and as thus adapted the pan is free to
revolve about its centre, 7. The upper surface of the pan is formed or provided
with a centre boss, 11, acting as a footstep to a centre shaft, 12, the upper end of
which is centred in the crosshead. 5.
The shaft, 12, is squared for a portion of its length and such portion is surrounded
by a boss, 13, which snugly fits the shaft with facility of vertical movement thereon.
From the centre boss, 13, there radiates a series of any suitable number (preferably
three) of arms, 14, on each of which there is mounted with facility of turning thereon
an edge runner, 15, which rests on and is supported by the top surface of the pan, 8,
and as thus adapted the said edge-runners are also free to be revolved around their
actuating centre shaft, 12, in so doing bearing on, rotating over and crushing the
cement or material contained by the pan.
The pan is constructed with an outer ring or flange, 16, for enclosing the material
under treatment and immediately adjacent to such flange it is formed with an annular.
grated bottom, 17, constructed of wire gauze or other suitable material and the

page_text: framing of which may serve to connect the said flange to the elge of the pan proper,
and adjacent to such annular grated bottom the said edge-runners, 15, are arranged
to rotate as best seen in the sectional part of Fig. 1. Vertically under the annular
grated bottom of the pan there is arranged an annular trough, 18, sufficiently wide,
or adapted with flared flanges, 19, for receiving all of the sufficiently crushed material
which falls through the grating, 17, and at suitable intervals the said trough is formed
with outlet openings, 20, by means of which the said material can escape from the
trough into a well, pit or receptacle below, or may be led by piping or other suitable
means of connection to where required to be conveyed. Depending from the under
surface of the pan at its said grated portion, 17, and into the trough, 18, there is
disposed a series of spatulas, 21, at suitable intervais apart, and which in the rotation
of the pan prevent accumulation of the said material in the trough by causing it to be
swept into the outlets, 20.
The pan, 8, is also adapted with a toothed rim, 22, which gears with an
actuating pinion, 23, keyed on a shaft, 2+, which is supported in a footstep, 25,
bolted to the base plate, 3, and is centred in the crosshead, 5, through which
it projects.
The shafts, 12, 24, are connected by any suitable arrangement of toothed gearing, 26,
which will cause the pan to be rotated in one direction vide the arrow, a, and the said
edge runners to be rotated in the opposite direction, vide the arrow, b, such gearing
also being preferably so proportioned as to cause the rollers to be rotated at about
three times the speed of the pan. By rotating the pan and edge runners in such
manner I attain very important practical advantages as compared with existing
grinding apparatus in which edge runners are rotated over a stationary pan, or in
which a pan is rotated under edge runners which are kept from rotating about the
axis of the pan, as the rotating parts may be driven at a lower speed to obtain any
given turn out and will be less liable to injury and will need less repair. A
further advantage consequent on rotating the pan and edge runners simultaneously
in opposite directions in the manner hereinbefore described is that in addition to
the usual crushing of the material the latter is ground as with a twisting motion
between the edge runners and the pan and which motion is. more effective than the
ordinary crushing motion.
The apparatus may be fitted with any suitable means for guiding the material in
the pan under the edge runners.
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,
1. The general construction and arrangement of apparatus for grinding cement
and analogous materials, substantially as hereinbefore described with reference to the
accompanying drawings.
2. In apparatus for grinding cement and analogous materials, simultaneously
rotating the pan and edge runners in opposite directions.
3. In apparatus for grinding cement and analogous materials, so mounting the pan
and edge runners and connecting them by gearing as that they may be simultaneously
operated in opposite directions.
Dated this 23rd day of Februo 1880
DAY, DAVIES & HUNT,
321, High Holborn, London, W.C.,
Agents for the Applicant.