IMPROVEMENTS IN MILLS FOR GRINDING GRAIN AND OTHER MATERIALS
Year: 1886

page_text: I SAMUEL BRASSINGTON BAMFORD of the firm of Henry Bamford and Sons of
Leighton Iron Works Uttoxeter in the County of Stafford Agricultural Engineere
do hereby declare the nature of the said Invention for "IMPROVEMENTS IN MILLS
FOR GRINDING GRAIN AND OTHER MATERIALS " to be as follows:-
My invention consists in constructing and arranging in the manner hereinafter
described the parts of mills for grinding. Mills constructed according to my
invention are particularly suited for grinding corn and other grain but may also
be employed for grinding other materials such for example as bones charcoal and
oil cake.
The grinding is effected between a pair of conical discs one of which is stationary
and the other rotates on a horizontal shaft. The rotating disc is mounted loosely
on its shaft and has a limited sliding motion thereon. The rotary motion of the
shaft which is driven by steam or other power is communicated to the disc by a
clutch keyed to the shaft. At the back of the rotating disc the shaft carries a
strong helical spring one end of which bears against the back of the said disc and
the other against a collar terminating the shaft. The end of the shaft bears
against the end of a screw working in the fixed framing of the mill. This screw
is turned by a hand wheel and by driving it home more or less the shaft can be
advanced. The coiled spring is thereby compressed and exerts greater pressure on
the rotating disc.
Each of the conical discs described carries a conical ring of hard or chilled iron
or steel attached thereto by bolts. These rings have a roughened or ribbed grinding
surface on both sides and being alike in size and shape can be interchanged. Hence
when the conical ring on the fixed disc has become worn on its acting or concave
surface it can be transferred to the rotating disc in which case its unworn or convex
surface becomes the acting or grinding surface. Similarly the conical ring which
was fixed to the rotating disc and whose convex surface was in that case the
grinding surface has become worn the said ring can be transferred to the fixed disc
when its concave unworn surface becomes the grinding surface.
Those portions of the discs near the axis are provided with rings having coarser
ribs or crackers. These inner rings are fixed in position by the inner edges of the
outer rings overlapping them. By these inner rings the grain or other material is
subjected to a preliminary crushing before it reaches the true grinding surfaces,

page_text: The clutch by which the motion of the shaft is communicated to the rotary disc
and which clutch as hereinbefore stated is keyed to the shaft has a long boss on
which one or more helical or screw like ribs or feathers are inade. This boss is
situated immediately under the bottom of the hopper and the grain or material to
be ground passing from the hopper to the said boss is by the said helical ribs or
feathers carried through the opening in the fixed disc and delivered between the
grinding surfaces. A sliding ring or sleeve surrounds the said boss and by sliding
the said ring or sleeve in one or other direction on the boss the rate at which the
material under operation is supplied to the grinding surfaces can be regulated.
•
Dated this eighth day of January 1886.
W. T. WHITEMAN,
Agent for the Applicant.
COMPLETE SPECIFICATION.
Improvements in Mills for Grinding Grain and other Materials.
. 11.
I SAMUEL BRASSINGTON BAMFORD of the firm of Henry Bamford and Sons of
Leighton Iron Works Uttoxeter in the County of Stafford Agricultural Engineers
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:-
$+
+4
My invention consists in constructing and arranging in the manner hereinafter
described the parts of mills for grinding.
Mills constructed. according to my
invention are particularly suited for grinding corn and other grain but may also
be employed for grinding other materials such for example as bones charcoal and
oil cake.
The grinding is effected between a pair of conical discs one of which is stationary
and the other is fixed on a horizontal shaft. At the back of the rotating disc the
shaft carries a strong helical spring one end of which bears against the said disc
and the other against a collar carried by the shaft. The end of the shaft bears
against the end of a screw working in the fixed framing of the mill. This screw
is turned by a hand wheel and by driving it home more or less the shaft and disc
can be advanced and the coiled spring compressed.
Each of the conical discs described carries a conical ring of hard or chilled iron
or steel attached thereto by bolts. These rings have a roughened or ribbed grinding
surface on both sides and being alike in size and shape can be interchanged. Hence
when the conical ring on the fixed disc has become worn on its acting or concave
surface it can be transferred to the rotating disc in which case its unworn or convex
surface becomes the acting or grinding surface. Similarly the conical ring which

page_text: was fixed to the rotating disc and whose convex surface was in that case the
grinding surface has become worn the said ring can be transferred to the fixed disc
when its concave unworn surface becomes the grinding surface.
Those portions of the discs near the axis are provided with rings having coarser
ribs or crackers. These inner rings are fixed in position by the inner edges of the
outer rings overlapping them. By these inner rings the grain or other material is
subjected to a preliminary crushing before it reaches the true grinding surface.
Figure 1 of the accompanying Drawing represents in vertical longitudinal
section a mill for grinding grain and other materials constructed according to my
invention and Figure 2 represents an end elevation of a portion of the same on a
smaller scale.
The same letters of reference indicate the same parts in both Figures.
a, bare the discs carrying the conical grinding rings or plates c, d and the
crackers or ribbed grinding rings or plates e, f. The disc a is mounted on the
horizontal driving shaft g and the disc b is secured to the fixed framing or part of
the mill by screws one of which is shown at a³. The conical ring or grinding
plate c is fixed to the disc a by screws and screw nuts as shown at i and the
conical ring or plate d is fixed to the disc by screws and screw nuts, at h. After
the ribbed grinding ring or plate e is placed upon its seat in the disc a the conical
ring or grinding plate c is placed on its seat in the said disc a and by being fixed
by the screws and nuts at i the said ring or plate c secures the ring or plate e in
its position the inner edge of the ring c overlapping the edge of the ring e.
Similarly the ribbed ring or plate f is secured in its position on the fixed part of
the mill by the conical ring or plate d fixed by the screws and screw nuts at h.
The grinding surfaces described are contained in the case of the mill formed by the
back disc b and the cover 62 best shown in elevation in Figure 2. The position of
the spout in the case or cover be through which the meal or flour is delivered is
represented at b³ in Figure 2. On the rotating disc a are flyers one of which is
marked a² in Figure 1 for the purpose of carrying round the meal or flour and
causing its delivery at the spout 63 k is a helical spring one end of which bears
against a shoulder on the shaft g and the other end against a collar 7 the latter
bearing against the brass or bearing m in which the shaft g turns and in which it
is capable of a sliding motion. By means of the hand wheel n screw p and screw
box the shaft g can be forced inwards so as to bring the moveable grinding rings
or plates cand e closer to the fixed grinding rings or plates d and f. When the
screw is relaxed the spring k forces the shaft g outwards and separates' the
opposed grinding surfaces of the mill. The disc a is fixed on the shaft g by
the screw and screw nut shown at r and the lubrication of the end of the shaft g
is effected by the arrangement represented at 8. After the shaft g has been adjusted
its position is fixed by the lever lock nut at t; u is the driving pulley and v the
fly wheel on the shaft gx is the hopper containing the material to be ground
and y is the feeding trough down which the material from the hopper travels and
is delivered by the spout y' upon the moveable cracker plate or grinding ring e.
is a perforated plate or screen by which the large particles of the material fed
to the hopper are separated and made to pass out of the mill by the side spout z.
Both faces of the conical plates or rings c, d made of hard or chilled iron or steel
have a roughened or ribbed grinding surface and as. the said plates are of the same
size and shape they can be exchanged when the two opposed surfaces are worn
that is to say the ring or plate & takes the place of the ring c and the ring c takes
the place of the ring d. By this change of position those surfaces of the rings
which were opposed to each other and have become worn become the back surfaces
and the unworn surfaces which had previously been the back surfaces are now
opposed to each other and become the acting surfaces and the efficiency of the mill
is renewed.
The grain or matter to be ground is first cracked or broken between the coarsely
ribbed cracker plates or rings e. f from whence the cracked or broken matter

page_text: proceeds to the conical grinding plates or rings c, d by the action of which it is
reduced or ground to the required fineness and is ejected by the flyers a* down the
spout b³.
Having now particularly described and ascertained the nature of my invention
and the manner in which the same is to be performed I declare that I claim as my
Invention of "Improvements in mills for grinding grain and other materials,"
First Making the grinding surfaces of mills of two similar conical rings or
plates both surfaces of which are ribbed or made into grinding surfaces so that
when one pair of the grinding surfaces of the said rings or plates is worn the
other pair of unworn grinding surfaces may be brought into position for use by
interchanging the said rings or plates substantially as herein before described and
illustrated in the accompanying Drawing.
Secondly-The combination with the said interchangable conical grinding rings
or plates of crackers or coarsely ribbed conical rings or plates for crushing or
breaking up the grain or matter before it reaches the true grinding surfaces of the
mill substantially as herein before described and illustrated in the accompanying
Drawing.