Improvements in Grinding Mills and Disintegrators.
Year: 1888

page_text: Date of Application, 29th Sept., 1888
Complete Specification Left, 27th May, 1889-Accepted, 10th Aug., 1889
PROVISIONAL SPECIFICATION.
Improvements in Grinding Mills and Disintegrators.
Charles EdwARD HALL of Meersbrook Bank, Sheffield, in the county of York,
Engineer do hereby declare the nature of this invention to be as follows:-
Firstly In arranging the grinding surfaces of Mills with Vertical Runners upon
one or two horizontal shafts, in combination with fixed surfaces, also vertical, secured
to an annular ring, bolted to the main framing, and of feeding, the material to be
ground through the top of said annular ring by means of a hopper; the said
Runners revolving in opposite directions.
Secondly In arranging the said Runners with their axis eccentrically or out of
line one with the other, as described in Letters Patent No. 1440 12th April 1877 and
granted to me.
Thirdly, In single Mills of placing the axis of the two grinding plates or discs,
or Runners concentric with each other, when both are driven, or when one is fixed
and the other driven, and feeding such Mills at the side at a distance from the
centre of the main shaft equal to about one third the diameter of the said discs.
In the last named arrangement for grinding some materials; I affix to the driving
shaft a set of straight or curved arms and provide the discs with long projections
or pins, so as to effectually shred or granulate the substances under treatment.
In order to carry out my invention according to the first and second parts of my
improvements; I construct two headstocks in each of which revolves a spindle with a
suitable driving Pulley keyed thereon. The said headstocks have an enlarged part at
their centre and this is made to receive between two strong flanges; an annular ring,
containing the feed hopper and two fixed grinding plates. The said plates are
renewable.
Upon each rotating spindle is fixed a grinding plate also renewable, and the
adjustment for finer or coarser grinding is effected by. moving the said spindles
bodily end wise; by means of a tail piece and screwed lock-nuts working against the
faces of the bushes in the main bearings. Lock-nuts are also used to advance or
withdraw the said tail piece which is carried in a bracket cast or affixed to each
headstock.
The grinding faces of the revolving plates or runners, are circular hoops secured
flatwise to the plates by means of bolts or rivets and these plates have rings of
concentric teeth or plain rings or other suitable projections to suit the operation to
be performed. The centre portion of the grinding plate, which may also be a separate
renewable disc, has radial corrugated grooves or other suitable indentations into
which the hard unground material works, to form a bed, causing the material to assist
largely in its own disintegration. These grinding surfaces may be of steel, chilled
metal or of stahleisen.
By constructing Mills in which the two main spindles are placed eccentrically, I
secure a more effective action upon the particles under treatment, and avoid clogging
of the Mill, as there are no neutral points or lines of coincidence at any point of
contact.
The speed at which I prefer to run the two grinding surfaces is much in excess of
that usually allowed for grinding by attrition. The former speed assumes something
of a disintegrating action with a higher centrifugal delivery than is usual according
to the present system of Mills.
When it is desired to grind to a fine powder; I apply an exhaust fan to the delivery
of the Machine and draw away the dust into settling chambers. The coarser particles
being returned by gravity to the Mill down a spout.
I
In arranging, a single Mill according to the third part of my Invention ;
employ a single headstock (carrying the said grinding plate and driving Pulley and

page_text: tailpiece) and this plate rotates against a fixed circular plate attached to an end plate
secured to the main framing of the Mill which has secured to it, the feed hopper at
one side and an outside bearing for the driving spindle.
For grinding or shredding certain materials, when it is desired to make both discs
rotate, I construct the headstock with four bearings and secure one disc to a hollow
spindle which has its bearings on the main frame adjacent to each other; such spindle
having suitable necks or collars which fix it end wise. The other disc has curved
arms cast with a suitable rim into which the renewable grinding ring or plate is
secured by Bolts and this dise is keyed to a solid shaft which passes through the afore-
said hollow shaft and is carried in bearings at the outside extremities of the Mill
framing. This shaft has a similar endwise adjustment for finer or coarser grinding
as explained with reference to the double Mill. In this case, the curved arms act as
a suction fan in regard to the feed inlet and outlet of the Mill greatly assisting in its
capacity for work.
Dated this 28th day of Sentember 1800
COMPLETE SPECIFICATION.
Improvements in Grinding Mills and Disintegrators.
CHARLES EDWARD HALL of Meersbrook Bank Sheffield in the County of York
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 stateinent :-
My Improvements in Grinding Mills relate partly to developements in Mills
described in Letters Patent No. 1440 12th April 1877 granted to me and partly to
Mills of the horizontal type and consist of:-
Firstly In arranging the said Mills horizontally with two sets of vertical Runners
in conjunction with two fixed or dead faces set in an annular ring casting, bolted
securely to the main foundation.or framing of the Mill and of feeding the material
to be ground through the Top of the said annular fixed ring by means of a hopper:
the said Runners-by preference but not of necessity revolve in opposite directions.
Secondly-In arranging the said Runners with their shafts out of line or
eccentric with each other as described in said Letters Patent No. 1440 and granted
.to me.
:
Thirdly-In placing the axis of the two grinding plates or discs concentric with
each other and the said annular ring, as in my duplex Mill where the said ring is
divided by a partition vertically; or in single Mills; when one is fixed and the other
driven, and of placing the feed hopper at the side at a distance from the centre of
the main shaft equal to about one third the diameter of the said discs.
In the last named arrangement for grinding some materials 1 affix to the driving
shaft a set of straight or curved arms, and provide discs with long projections or
pins so as to effectually shred or granulate the substances under treatment.
In order to carry out my invention according to the first and second parts of my
improvements I construct two, headstocks combined with a massive foundation frame,
in each of which revolves a spindle with the necessary pulleys and grinding plates,
and in order that the same may be fully understood I have appended three sheets of
drawings with explanatory letters of reference, which letters are common to all the
figures
Fig. 1 Sheet 1 is a longitudinal section of my improved mill. Fig. 2 is a front
view of one kind of grinding plate. Fig. 3 is a similar view of another form of plate.
Fig. 4 is a longitudinal section of a duplex Mill. Fig. 5 Sheet 2 is a longitudinal
section of my improved Disintegrator according to the third part of my invention.
Figs. 6 & 7 shew the front view in each case of the grinding or shredding discs.
Figs. 9 & 10 are longitudinal sections of my Mills in which rotating cages and
beaters are used for grinding wet and clogging substances. Fig. 8 is likewise a
longitudinal section of a single disc mill in which only one disc revolves.

page_text: Figs. 11. 12 & 13 Sheet 3. shew the application respectively of the spring and
weight for releiving the disc in case of over-feeding or of any foreign substance being
introduced.
'
In each case the mill consists of a main bed plate A. A. having two or four
bearings B. B. cast thereon, on which spindles C. C. rotate with the driving pullies C¹
and the face plates D. to which are secured the renewable corrugated faces E. & the
serrated or plain rings F for breaking up and grinding the material.
The annular ring casting G. with its two grinding rings plain or serrated F¹ secured
thereto by bolts and the feed hopper H. which is bolted to the main framing A
between two flanges g¹. The grinding faces E are made to approach or recede from
the fixed faces F1 by means of a screwed tail-piece J through the bearing and operated
by a hand wheel and lock nuts K. To prevent the machine being jammed when at
work the pressure necessary for grinding may be put on by a weighted lever K & M.
which operates through a fulcrum & two collars on the said tail pin J. Fig. 11 or an
alternative spring arrangement as shewn at Figs. 12 & 13. where the tail piece J has
a coiled spring N pressing between two collars against the spindle end. A cover L is
provided which encloses the upper half of the Mill and through which the hopper H
protrudes. The axis of the spindles C, are eccentric to each other in Fig. 1.
In the duplex Mill, Fig. 4, they would be fixed preferably in a line although not so
shown in the Drawing. The partition N, divides the action of the Mill and enables
two qualities of grinding or two different materials to be operated upon at the same
time.
According to the third part of my Invention, Fig. 5 in Sheet 2 represents my
improved Mill in longitudinal section; Fig. 6, is a face view of the grinding disc D.
with its serrated grinding ring E and openings for entrance of material H from side
hopper. Fig. 7, is the opposite grinding dise D with serrated ring, F and curved
arms G for driving the entering matorial between the said serrations, both are keyed
to the main spindles C. Fig. 8, is a longitudinal section of a single Mill with the
grinding disc D and corrugated breaking disc E and outer ring F working into a
similar disc and ring E¹ and F¹ secured to the end plate of Mill to which is attached
the feed hopper H. The whole mounted upon the framing A. Fig. 9 is a longitudinal
section of a Mill, constructed with discs D and pins E and F, and beaters G. In
Figs. 5 and 9, the discs and cages are mounted upon two spindles, one working within
the other. The same letters in all the figures, denote the same parts and the operation
of these Mills is as follows:-
The material is fed into the hopper H and passes under the operation of the radially,
corrugated plates which act as breakers, driving the stuff between the serrated rings
where it is further reduced to powder or other finely pulverised condition. It is then
delivered at the periphery and may be elevated by an ordinary bucket Elevator whence
it passes over a vibrating screen and is separated by an exhaust fan, when fine grinding
is required, the rough stuff or tailings fall back by a shoot into the Mill hopper H for
further treatment in any well-known manner.
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 1
claim is:
-
Ist. The arrangement of Grinding Mills with radial corrugations and circular
serrated rings, as shown on Figs. 1 and 8 and in detail at Figs. 2 and 3.
2nd. The general arrangement of parts as shown in Figs. 1. 4. 5. 8 and 9. & 10.
substantially as described and illustrated.
1000