An Improved Sifter and Mixer.
Year: 1889

page_text: Date of Application, 1st July, 1889
Complete Specification Left, 17th Aug.. 1889-Accepted, 21st Sept., 1889
PROVISIONAL SPECIFICATION.
An Improved Sifter and Mixer.
I, WILLIAM GARDNER, of Southgate Street, Gloucester, in the County of Gloucester,
Milling Engineer, do hereby declare the nature of this invention to be as follows:-
My invention relates to machines for sifting and mixing materials, and it
consists in improvements in both the sifting and in the mixing mechanism of such
machines.
The objects of my invention are:-
1st. To provide means for enabling the surface of the sieve to be kept clean and at
the same time to ensure the "tailings," or parts of the materials to be mixed which
are too large to pass through the meshes of the sieve, to be automatically discharged
at one end of such sieve.
2nd. To facilitate the removal of the sieve at will, when required to repair same or to
replace it by a sieve having a finer or coarser mesh.
3rd. To improve and simplify the mixing mechanism, and to enable same to be more
easily examined and cleaned.
The material or materials to be sifted are supplied to one end of the sifting
mechanism (preferably by a hopper of any suitable construction and provided with a
shaking feed), and fall on to the sieve, which is fixed in a suitable frame, and is of
semicircular form, a shaft being mounted in suitable bearings in the frame in the axis
of the sieve, and carrying a brush of spiral or helical form, which is in contact with
the upper surface of the sieve. At the opposite end of the sieve to which the feed is
supplied a shoot or outlet is arranged. The axis of the brush is caused to revolve, and
the helical or spiral brush in its rotation causes the material delivered to one end of
the sieve to travel along to the opposite end thereof, whereby the parts of such
material which are sufficiently small are in its travel caused to pass through the sieve,
the meshes of which are kept open by the contact of the brush there with, while the
tailings," or parts of the material which are too large to pass through the sieve, are
conveyed to the opposite end thereof, and discharged through the outlet or shoot
above described.
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The sieve is mounted on an end piece or section which fits into a corresponding
opening in the case or frame, so that it can be slid out from under the brush, at the
opposite end to where the power is applied to the brush spindle, when requisite to
examine or repair, or to replace same by a new sieve or by a sieve having a different
mesh.
Part of the sieve casing is preferably provided with a flap or lid for the purpose of
inspection, in order to see whether the sifting action, and also the cleaning operation
of the sieve by the brush, is being satisfactorily effected.
In order to provide for the wear and tear of the brush, and the consequent diminu-
tion of its diameter, the bearings of the axis thereof are made adjustable, so that they
may be lowered when requisite, and thus bring the lower surface of the brush again in
contact with the top of the sieve.
$
The sifting apparatus above described may be arranged above a mixing apparatus,
consisting of a shaft mounted to revolve in suitable bearings in a closed casing in
which the materials to be mixed fall from the sieve. This shafts carries one, two, or
more helical blades running in the same direction and parallel to each other along the
axis, the bottom of the casing being semicircular to conform to such blades. The
helical blades have formed thereon, or secured thereto at suitable distances apart, bars
or segments of helices set in the opposite direction or at an opposite angle to that of
the helical blades secured to the axis. The latter is caused to rotate by any suitable
means, and the effect is, that whereas the blades secured to the axis tend to cause the

page_text: materials to be mixed to travel along the casing in one direction, the bars or segments
mounted on such blades tend to cause the materials to travel in the opposite direction,
the result being that as the whole agitator revolves the constituent parts of such
materials are continuously displaced in the casing and become intimately mixed.
The bottom of the agitator casing is hinged, so that it can open downwards, and
thus enable the casing itself and also the blades of the agitator to be examined, cleaned
and repaired, when requisite; and may also serve to enable the materials when
thoroughly mixed to be discharged from the apparatus, but I prefer to employ an
outlet or discharge spout in the casing for the latter purpose, such outlet, if desired,
being provided with a slide to regulate the discharge.
Motion may be imparted to the shaft of the brush of the sifting mechanism, and
also to that of the agitator or mixer, in any suitable manner, and either independently,
or from one of such shafts to the other by any suitable transmission.
Dated this 1st day of July 1889.
ALLISON BROS.,
Agents for the Applicant.
COMPLETE SPECIFICATION.
An Improved Sifter and Mixer.
I, WILLIAM GARDNER, of Southgate Street, Gloucester, in the County of
Gloucester, Milling 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 statement
My invention relates to machines for sifting and mixing materials, and it consists
in improvements in both the sifting and in the mixing mechanism of such machines.
The objects of my invention are:-
1st. To provide means for enabling the surface of the sieve to be kept clean and at
the same time to ensure the "tailings," or parts of the materials to be mixed, which
are too large to pass through the meshes of the sieve, to be automatically discharged
at one end of such sieve.
2nd. To facilitate the removal of the sieve at will, when required to repair same.or
to replace it by a sieve having a finer or coarser mesh.
3rd. To improve and simplify the mixing mechanism, and to enable same to be more
easily examined and cleaned.
Fig. 1 of the accompanying drawing is a longitudinal section of the machine.
Fig. 2 is a transverse section of same.
Fig. 3 a transverse section of the brush and sieve.
Fig. 4 an end elevation of the rear end of the brush, and
Fig. 5 a transverse section of the top sieve or casing.
The material or materials to be sifted are supplied to one end of the sifting
mechanism (preferably by a hopper A of any suitable construction and provided with
a shaking feed as shown), and fall on to the sieve B, which is mounted in a suitable
frame C, and is of semicircular form, a shaft D being mounted in suitable bearings in
the frame in the axis of the sieve B, and carrying a brush E of spiral or helical form,
which is in contact with the upper surface of the sieve B. At the opposite end of the
sieve B to which the feed is supplied a shoot or outlet F is arranged.
The axis D of
the brush E is caused to revolve, and the helical or spiral brush in its rotation causes
the material delivered to one end of the sieve B to travel along to the opposite end
thereof, whereby the parts of such material which are sufficiently small are in its travel
caused to pass through the sieve B, the meshes of which are kept open by the contact
of the brush therewith, while the "tailings," or parts of the material which are too
large to pass through the sieve, are conveyed to the opposite end thereof, and dis-
charged through the outlet or shoot F above described.
The sieve B is mounted on an end piece or section b which fits into a corresponding
opening in the casing or frame C, so that it can be slid out from under the brush E,

page_text: (as shown in dotted lines in Fig. 1), at the opposite end to where the power is applied
to the brush spindle, when requisite to examine or repair, or to replace same by a new
sieve or by a sieve having a different mesh.
Part of the sieve casings is preferably provided with a flap or lid G for the purpose
of inspection, in order to see whether the sifting action, and also the cleaning opera-
tion of the sieve by the brush, is being satisfactorily effected; and also if desired to
introduce directly into the mixer beneath any substance or substances which do not
require to be previously sifted.
In order to provide for the wear and tear of the brush E, and the consequent
diminution of its diameter, the bearings d of the axis D thereof are made adjustable,
so that they may be lowered when requisite, and thus bring the lower surface of the
brush E again in contact with the top of the sieve B. When necessary to sift sub-
stances which are liable to lump into pieces which a moderate pressure would readily.
break up, the brush E instead of being made in the form of a continuous spiral from
end to end may have a portion of its length divided into two, three or more sections,
as shown at E, and such sections filled with lines of bristles, fibres, or other suitable
material, running lengthwise and having a slight twist in relation to the axis D. The
forward edge of each of the lines or sections of bristles, fibres, or other suitable
material E¹, in the direction of rotation of the brush, is made of less diameter, than the
spiral portion of the brush, and gradually increases in diameter to its back edge,
where it is of the full diameter of the spiral portion. Any lumps in the material will
thus on leaving the spiral portion of the brush E come under the action of the lines or
sections of bristles, fibres, or other suitable material E', and as the brush revolves such
lumps will be first acted upon by the forward edges of the lines or sections and
pressed against the sieve B, the increasing diameter of such lines or sections towards
their back edge causing a gradually increasing pressure to be exerted on such lumps,
thereby reducing same and enabling the greater portion thereof to pass through the
sieve. The twist of the lines or sections E ensures the advance of the material along the
sieve as it is crushed. The part of the brush which is formed into longitudinal twisted
sections E¹ is also preferably enclosed on its upper side by a semicircular top casing or
sieve B', so that this portion of the brush revolves in a barrel and the crushing action
on the lumps will take place all round. The semicircular casing B¹ may be perforated
or not as desired.
When the brush is provided with longitudinal twisted sections of bristles, fibres, or
other suitable material, on part of its length, at the extreme rear end of each of such sections
a small portion of the bristles, fibres, or other suitable material are again arranged in
a spiral form of the full diameter of the brush as shown at E³, Figs. 1 and 4, and form
a seginental or sectional continuation of the spiral E of the first part of the brush, the
object of such end spiral being to ensure the prompt delivery of the tailings or parts
of the material which will not pass through the sieve, through the outlet or shoot F,
as soon as they leave the lines or sections of bristles, fibres, or other suitable material E¹,
and arrive at the discharge end of the sieve.
The top sieve B' is also mounted in a frame which can be adjusted in relation to
the brush and can be taken out through the top of the casing of the machine, for which
purpose such top is made removable.
The sifting apparatus above described may be arranged above a mixing apparatus,
consisting of a shaft H mounted to revolve in suitable bearings h in a closed casing I,
into which the materials to be mixed fall from the sieve B. This shaft H carries one,
two, or more helical blades K running in the same direction and parallel to each other
along the axis, the bottom of the casing I being semicircular to conform to such
blades K. The helical blades K have formed thereon, or secured thereto at suitable
distances apart, bars or segments of helices L set- in the opposite direction or at an
opposite angle to that of the helical blades K secured to the axis H. The latter is
caused to rotate by any suitable means, and the effect is, that whereas the blades K
secured to the axis Ĥ tend to cause the materials to be mixed to travel along the
casing I in one direction, the bars or segments L mounted on such blades K tend to
cause the materials to travel in the opposite direction, the result being that as the

page_text: whole agitator revolves the constituent parts of such materials are continuously dis-
placed in the casing and become intimately mixed. If desired the casing of the
agitator may be circular and the material to be mixed be delivered to one end
thereof.
The bottom of the agitator casing I is hinged at I¹, as shown in Fig. 2, so that it
can open downwards, and thus enable the casing itself and also the blades K and L of
the agitator to be examined, cleaned and repaired, when requisite; and may also
serve to enable the materials when thoroughly mixed to be discharged from the
apparatus, but I prefer to provide an outlet or discharge spout M in the casing I for
the latter purpose, such outlet, if desired, being provided with a slide m to regulate
the discharge.
As the blades K are continuous and are set so that the rotation of the agitator tends
to cause the material to travel towards the outlet M, while the bars L tending to cause
such material to travel away from such outlet are interrupted or segmental, the
material will gradually be advanced by such blades K to the outlet M.
Motion may be imparted to the shaft D of the brush E of the sifting mechanism,
and also to that H of the agitator or mixer, in any suitable manner, and either
independently, or from one of such shafts to the other by chain gearing, as shown, or
by any other suitable transmission.
Having now particularly described and ascertained the nature of my said inven-
tion, and in what manner the same is to be performed, 1 declare that what I
claim is :-
1. The improved combined sifter and mixer, constructed and operating substantially
as specified.
2. The improved sifter consisting in a brush of spiral or helical form revolving in
contact with a semicircular sieve, substantially as specified.
3. The improved brush having a portion of its length provided with longitudinal
twisted sections of bristles, fibres, or other suitable material, the forward edges of
which are of smaller diameter than, and gradually increasing diameter towards, the
rear edges of such sections, in the direction of the rotation of such brush, the whole
in combination with a circular casing within which such longitudinal sections revolve,
and the bottom part or the whole of which casing is perforated so as to form a sieve,
all substantially as and for the purpose specified.
4. A semicircular sieve mounted on a frame which can slide into the casing of the
sifter into position beneath a sifting brush, which is caused to rotate within such
casing and which acts in conjunction with the sieve, substantially as specified.
5. The improved mixer consisting in a shaft revolving within a casing, the bottom
half of which is of semicircular form, such shaft carrying one, two, or more helical
blades running in the same direction and parallel to each other along such shaft, and
having formed thereon or secured thereto at suitable distances apart, bars or segments
of helices set in the opposite direction or at an opposite angle to the helical blades
themselves, all substantially as specified.
6. The improved mixer having the bottom half of its casing hinged in order to
allow ready access to the agitator or mixing blades, substantially as specified.
Dated this 15th day of August 1889.
ALLISON BROS.,
Agents for the Applicant.