Improvements in and relating to the Construction of' Mills used for Grinding. Flint, Stone, Pigments, and the like Materials.
Year: 1891

page_text: Date of Application; 1st June; 1891
Complete Specification Left, 24th Oct., 1891-Accepted, 28th Nov., 1891.
PROVISIONAL SPECIFICATION.
Improvements in and relating to the Construction of' Mills used for
Grinding. Flint, Stone, Pigments, and the like Materials.
THOMAS WILLIAM BRITTAIN, London Road, Chesterton, Staffs. Ironfounder,
do hereby declare the nature of this invention to be as follows:-
This my invention has reference to an improved construction of mill for use in
grinding flint-stone pigments and the like materials, and the object of my said
invention is to construct such mills in such a manner that they will grind in a
more economical manner, than by the method or means at present adapted.
To carry my said invention into practice I fix or fasten together two or more
segments of French burr-stone of suitable shape and size by means of. metal' bolts
and. straps, or a metal casing; through the centre of the said burr stones I form
a parallel round hole.
Through the centre of the said hole I pass a metal shaft of suitable shape and'
size,, which is supported by and capable of rotating in a bearing or Bearings at
one or both. ends of the casing, on. the said shaft I key fasten or fix a suitably,
shaped metal jaw or its equivalent to which jaw I attach a drag, link having, a
suitably shaped burr-stone connected to its free end' by any suitable means.
When the said shaft and drag, link to which the burr-stone is attached are
revolved it will be understood that the latter will be caused by its centrifugal
motion to fly outward and crush the material' coming between the face of the
said burr stone and the periphery of the parallel hole formed through the
segmental burr stones.
Both sides of the segmental burr stones. being, closed or boxed in any suitable
manner, the material or materials for grinding being introduced into the parallel
round hole through a suitably shaped aperture or hopper formed in or attached'
to one of the side plates, the material as it is ground passing or falling through
an aperture fitted with a detachable grid or mesh adjacent to one of the sides of
the said burr stones, the ground material falling into a sieve placed below, to
which sieve a rotary or agitating motion. is. imparted by any suitable means,, and
between the framing supporting the stones, the material sifted through the. sieve
falling into a suitable receptacle below. One set of stones may be used. asi
described, or two or more sets may be connected together by any suitable means,
the material or materials to be crushed being passed into the parallel round hole.
through an aperture or hopper at one or both sides of the. end sets and. as. it is
ground, it is moved or passed from one set of stones to the. next set. by metal
propellers or blades of suitable shape and size fitted or fixed to. and revolving
with the central revolving shaft. between each set of stones, the said shaft
extending from end to end of the two or more sets of stones, and supported at:
each end or at intervals. by suitable bearings. The. ground. material passing.
through the grid or mesh of the last set of stones, may either fall into an agitated
sieve or, into a suitable. receptacle for receiving same placed below. The several.
sets of stones being mounted on suitable framing, made of or from metal,, wood or.
other suitable: material or materials.
Dated this 30th day of May 1891.
JOHN NEWTON,
Agent for Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in and relating to the Construction of Mills used for
Grinding Flint-stone, Pigments, and the like Materials.
THOMAS WILLIAM BRITTAIN, London Road, Chesterton, Staffordshire, Iron
founder, 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 my invention has reference to that class of machines known as mills or
pulverizers which are used. for crushing or reducing to powder flint-stone, pig-
ments, minerals, grain, flour and other substances, and the object of my said
invention is to construct the hollow cylinder of such machines in two or more
segments or sections, and the "crushers" fitted or fixed to the ends of the drag
links of burr-stone, preferably that known as French burr-stone in such a manner
that when the said drag-links and "crushers" are caused to revolve within the
said burr-stone cylinder, the substance under treatment will be ground or crushed
in less time and in a more economical manner than by the method or means at
present adopted.
It having been found by practical experience that similar machines in which
the rollers and the cylinder are made of metal, that the friction caused by the
rolling and rubbing action of the rollers within the cylinder in many instances
whilst pulverizing a substance or substances greatly deteriorates the marketable
value of the ground substance or substances, and I find by experiment by con-
structing the hollow cylinders and "crushers" or rubbers of such mills or
pulverizers from burr-stone that I am enabled to pulverize various substances to
various degrees of fineness in a shorter time without reducing their marketable
value.
In order that my said invention may be more readily understood and explained
in detail I have hereunto annexed a sheet of drawings on which letters of reference
are marked.on similar parts on all the figures alike.
DESCRIPTION OF DRAWINGS.
Figure 1 is an elevation of the cylinder of a mill or pulverizer in section con-
'structed according to my invention of segmental burr stones, shewing two drag-
links distended, and the "crushers" or burr-stones fitted or fixed to the said
drag-links, bearing against the internal periphery of the said segmental burr-stone
cylinder.
Figure 2 is a longitudinal sectional elevation of the segmental burr-stone
cylinder shewn at Figure 1.
The said figures being drawn about one-twelfth of their full size.
On the drawings hereunto annexed I have shewn by way of example a cylinder
built up or constructed of seven segments of burr-stone a, through which connected
or united burr-stones a parallel, conical, concave or V shaped round hole is formed,
the said segmental stones being held together by means of metal straps or bands, and
closed at its ends by metal plates c, d, the end plated being constructed or provided
at its top end with an opening or hoppere through which the substance or
substances to be pulverized is or are passed to the interior of the segmental burr-
stone cylinder, the end plate c being provided near its bottom end with an opening
and shoot for conveying the material away after it is pulverized. Through the
centre of the hollow segmental cylinder I pass a horizontal metal shaft of suitable
shape and size, which shaft is supported by and capable of rotating in a bearing
or bearings at one or both ends of the casing or cylinder. On the aforesaid shaft g
I key fasten or fix a suitably shaped metal jaw or its equivalent, to each end of
which jaw I attach by any suitable means a drag-link i having a suitably shaped
1.

page_text: French burr-stonej connected to its free end, each said burr-stonej being about
one inch shorter in length than the cylinder between the plates c, d. When the
said shaft g is caused to revolve it will be understood that the drag links i and
the burr-stones j will rotate and by centrifugal force fly outward, and crush the
material between the faces of the said burr-stones and the internal periphery of
the hollow cylinder, this dragging or rubbing action being most effective in
reducing various substances to a fine powder. Dotted lines and y at Figure 2
shew other shapes of stone applicable to my invention.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed declare that what I
claim is,
1st. The use of stone, preferably that known as French burr-stone in the con-
struction of the hollow cylinders of mills or pulverizers which are used for crushing
or reducing to powder flint-stone, pigments, minerals, grain, flour and other similar
substances, as herein substantially described and set forth.
2nd. The use of stone, preferably that known as French burr-stone in the
construction of the "crushers or rollers of mills or pulverizers which are used
for crushing or reducing to powder flint-stone, pigments, minerals, grain, flour, and
other similar substances, as.herein substantially described and set forth.
3rd. The use of stone, preferably that known as French burr-stone in the
construction of the hollow cylinders, and the use therewith of "crushers" or rollers
made of or from burr-stone for mills or pulverizers such as are used for crushing
or reducing to powder flint-stone, pigments, minerals, grain, flour and other similar
substances as herein substantially described and set forth.
Dated this
de of October 1801
JOHN NEWTON,
Longport, Staffordshire, Agent for Applicant.