Improvements in or relating to Grinding, Crushing, or Pulverizing Mills.
Year: 1896

page_text: Date of Application, 23rd June, 1895
Complete Specification Left, 23rd Mar.. 1897-Accepted, 8th May, 1897
PROVISIONAL SPECIFICATION.
Improvements in or relating to Grinding, Crushing, or Pulverizing
Mills.
We, WILLIAM JOHNSON, and HARRY WALKER, of the Castleton Foundry,
Armley, Leeds, in the County of York, Engineers, do hereby declare the nature
of this invention to be as follows:-
This invention relates to that class of machinery in which the crushing, grinding,
or pulverizing effect is produced by the rotation or centrifugal action of balls or
rollers working within a cylindrical ring or casing, and it is designed to render the
machine described in the Specification of Letters Patent granted to Charles
Lucop, the Twentieth day of April 1875 No. 1429, and also that described in the
Specification of Letters Patent granted to Richard Cook the Eighteenth day of
October 1880, No. 4244, more satisfactory and practical in their operation as well
as to enable a mill or pulverizer to work with a greater degree of practical
efficiency than it has hitherto been capable of doing.
The objects of this invention are to reduce the wear and tear on the fittings of
the shaft, and to make the fittings less costly than at present but at the same time
more efficient, and also to reduce the labour in the taking off and replacing of
fittings on the said shaft."
According to this invention we make a shaft having a portion of its length
nearest its centre of a square section, or provided with any number of flat sides.
On this square or flat sided portion of the shaft is fitted a central piece or carrier
made of ordinary cast steel or other suitable material. This central piece has ribs
provided on each of its sides and it is held in position on the shaft by means of a
key or other equivalent fastening driven through the steel casting and shaft at
right angles to the shaft itself.
Two drivers, arms or carriers (which carry the balls or rollers in slots) are
mounted one on either side of the central piece or carrier and inside the afore
mentioned ribs.
These drivers, arms or carriers are made from a steel or iron or any other
suitable material tempered or hardened as to be incapable of being operated upon
by any class of cutting tool such as a file or chisel.
The centre of the drivers, arms or carriers are fitted with a hoop of wrought iron
or any other suitable material which can be worked and acted upon by cutting
tools for the purpose of fitting them on the shaft.
Propellors or stirrers are fitted on either side of the drivers, arms or carriers
and they are also made of the extremely hard steel or other materials tempered
or hardened as before mentioned. The centres of these fittings are also provided
with a hoop of wrought iron or other material capable of being acted upon
by cutting tools for the purpose of fitting them on the shaft as before described.
The sides of the propellors or stirrers are made with ribs, corresponding
with the ribs on the centre piece or carrier; these last named ribs in each
instance grip the drivers, arms or carriers, and they are made to fit between
them.
On the outside of each propellor or stirrer are fitted keys at right angles to the
haft which give a pressure towards the drivers, arms or carriers and the centre
iece or carrier

page_text: By this means suitable compression or pressure is obtained for securing the
propellors or stirrers and drivers, arms or carriers to the shaft by pressing and binding
them on each side of the centre piece or carrier by means of the keys, thus making the
whole of the fittings secure, and capable of being removed and replaced in a very
short time and at very little expense.
This invention is applicable to grinding mills or pulverizers having one or any
number of rings, rollers, drivers, propellors or stirrers as may be found requisite in
actual practice.
Dated this Twentieth das of June 1896
WILLIAM JOHNSON.
HARRY WALKER.
COMPLETE SPECIFICATION.
Improvements in or relating to Grinding, Crushing, or Pulverizing
Mills.
We, WILLIAM JOHNSON and HARRY WALKER, of the Castleton Foundry,
Armley, Leeds, in the County of York, Engineers, 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:-
This invention relates to that class of machinery in which the crushing, grinding,
or pulverizing effect is produced by the rotation or centrifugal action of balls or
rollers working within a cylindrical ring or casing, and it is designed to render the
machine described in the Specification of Letters Patent granted to Charles
Lucop the Twentieth day of April 1875 No. 1429, and also that described in the
Specification of Letters Patent granted to Richard Cook the Eighteenth day of
October 1880, No. 4244, more satisfactory and practical in their operation as well
as to enable a mill or pulverizer to work with a greater degree of practical
efficiency than it has hitherto been capable of doing.
The objects of this invention are to reduce the wear and tear on the fittings of
the shaft, and to make the fittings less costly than at present but at the same time
more efficient, and also to reduce the labour in the taking off and replacing of
fittings on the said shaft.
In the drawings hereunto annexed :-
Fig. 1 is a front elevation and Fig. 2 an end elevation of our improvements
applied to centrifugal grinding, crushing, or pulverizing mills or the like.
Figs. 3 to 7 are details of our improvements.
Figs. 8 and 9 are respectively front and end elevations of our improvements
drawn to an enlarged scale.
Like parts in all the views are marked with similar letters of reference.
According to this invention the fittings consist of a centre carrier A fixed to the
grinding mill shaft B, together with solid drivers, arms, or carriers C (hereafter
termed drivers C) and solid propellors or stirrers D, the centre carrier A and
propellors D being provided with carrying ribs or jaws E. The cotters F and
nuts G are used for securing and preventing any side movement of the fittings on
the shaft.
Grinding rollers or balls (rollers H are shown in the drawings) fitted with
spindles I, work in the slots J provided in the drivers C as shown. K represents
the inside diameter of the grinding ring against which the rollers H are caused to
come in contact by the centrifugal force generated in the revolving mill shaft on
which our improved fittings are fixed.
The shatt B is provided with a portion of its length nearest its centre of a square

page_text: section, or having any number of flat sides, the other portions of the shaft being
turned up round to the required size.
On the square portion of the shaft is fixed the centre carrier A (made of ordinary
cast steel or other suitable material) which is provided with a hole of the same
contour as the shaft at this point, said carrier A being provided with carrying
ribs E.
This fitting is forced on to the shaft by hydraulic or other pressure and is
permanent, no wear from the material under treatment affecting it. To provide
against any side movement when compressing or fixing the other herein described
fittings on the shaft, a pin or rivet L is provided which is driven right through
carrier A and shaft B at right angles to the shaft itself.
On each side of centre carrier A, and between the carrying ribs or jaws E are
fixed the drivers C, having each of their ends or faces M made thicker than their
centres, to allow for any wear caused by the rollers H revolving against and between
the driver faces which come next to the sides of the rollers.
The holes N in the centres of the drivers C are provided with a bush of any.
suitable soft material capable of being machined and acted upon by cutting tools,
the other portion of this fitting being of a very hard and tough material which is
calculated to resist wear, and which cannot be machined, the holes themselves being
bored to fit easy on the shaft B.
The carrying ribs or jaws E on the centre carrier A only grip part of the
thickness of the drivers C in the centre at their thinnest portions.
After the drivers C are in position, the propellors or stirrers D,-which are
provided with corresponding carrying ribs or jaws E, like those of the centre
carrier A, and which are made with a centre bush O of soft material in exactly the
same manner as the drivers C (the other portion of the propellors or stirrers
consisting of the same hard material as the drivers C)-are placed next to and
outside the drivers C, the carrying ribs or jaws E gripping half the thickness of
the drivers in the same manner as the ribs of the centre carrier A.
To compress the drivers C and propellors or stirrers D on either side of the
centre carrier A, cotters F are driven into holes F in the shaft, the said holes
having draw to permit of the cotters themselves being partly recessed into the
propellor bosses, and are also provided with safety pins opposite to driving ends to
prevent their working out of the shaft when the mill is running.
In place of the cotters suitable nuts G may be used to secure the fittings one to
the other, the results being practically the same as with the cotters F.
The drivers C can be reversed, that is to say when one side of a driver has been
worn on its face at M by the roller H, it can be taken off the shaft B and turned
round thereby bringing the worn face outside and unworn face from the outside to
the inside and next to the roller H. By reversing the drivers C (which are the
fundamental fittings) they can be completely worn out before being replaced.
This movement also allows of both sides of the slots J to be thoroughly worn
out, making each side of the slots to lead and drive alternately.
When the grinding rollers H are in position between the driver faces M, the
spindles I do not rest on the bottom of the slot or jaw, but are kept a certain
distance up the slot quite free and clear of the bottom of the slot, the roller itself
being in contact with centre carrier A when they are in their back position.
It will be readily observed that,-when the rollers H are forced back with their
spindles I up slots J, by coming in contact with the material being ground,-the
shock, blow, or weight of such movement, combined with the dead weight of the
roller itself, is not taken up by the spindles which are clear of the slot or jaw
bottoms, but by the rollers which are the largest bodies or sections and which come
in contact with the centre carrier A..
The length of the roller spindles I are such as to only allow of their working in
half the thickness of the driver end or slot J thereby leaving half the distance
through the slot or jaw unworn and practically new when the drivers C require
to be reversed, after which the unworn portion of slot J is brought into use.

page_text: Four distinct wears can be obtained from the driver slots J, firstly by running
the mill backwards and secondly by running the mill forwards before changing or
reversing the drivers C; thirdly by running the mill backwards and fourthly by
running the mill forwards after the drivers C have been reversed. The spindles I
only bear upon one fourth of the wearing portion of the slots J when first put to
work, the remaining three fourths being utilised according to the running back-
wards and forwards of the mill and the reversing of the drivers C.
. It will readily be seen that the herein described fittings are safe in their working
as there are no small renewable parts to break loose inside the mill.
By dispensing with such small parts and employing our herein described fittings
having a small amount of machine work expended upon them in manufacture, it
will enable them to be used and replaced at a small cost as compared with other
systems.
Moreover the interlocking or clutch arrangement obtained by this invention
allows the fittings to be attached and detached to and from the aforesaid shaft in
a very short space of time by the person or persons using the mill.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what we
claim is :-
1. In grinding, crushing, or pulverizing mills, our improved fittings consisting
essentially of shaft B, provided with centre carrier A, drivers or carriers C,
propellors or stirrers D having carrying ribs or jaws E for the purpose of carrying
or securing the fittings required for working the crushing rollers (or balls) H and
for carrying fittings for the purpose of propelling or stirring the material in the
mill, said fittings forming an interlocking device or clutch substantially as herein-
before and illustrated.
2. In grinding, crushing, or pulverizing mills the herein described fittings
provided with soft centres or bushes for the purpose of being machined to size,
and fittings made from hard and tough material incapable of being acted upon by
cutting tools, and without small renewable parts; said fittings themselves
constituting the renewable parts, substantially as herein before described and for
the purposes set forth.
3. The combination with the herein described fittings for grinding, crushing, or
pulverizing mills, of any suitable number of cotters F, or nuts G, or their
equivalents, for the purpose of compressing the fittings and holding same in the
carrying ribs or jaws E as herein before described and illustrated.
4. In grinding, crushing, or pulverizing mills drivers C fitted with slots J and
capable of being reversed with a view to their being completely worn out before
renewal substantially as hereinbefore described and illustrated.
5. In grinding, crushing, or pulverizing mills our improvements constituting the
combination and arrangement of parts substantially as herein before described and
illustrated with reference to Figs. 1 to 9 of the accompanying drawings.
Dated this Twentieth day of March 1897.
WILLIAM JOHNSON.
HARRY WALKER.