Improvements in Machinery for Washing Grain and the like.
Year: 1896

page_text: Date of Application, 5th Feb., 1896-Accepted, 18th Apr., 1895
COMPLETE SPECIFICATION.
Improvements in Machinery for Washing Grain and the like.
I, GUSTAV DAVERIO, of No. 1 Leonhardgasse, Zurich I, Switzerland, 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:-
This invention relates to a machine for washing grain or other material of a like
nature (hereinafter included in the term grain) in which the grain drops from a
suitable receptacle-for instance, a hopper-into a vessel containing water, in
which it becomes immersed to a certain depth and the heavy grain (that is to say,
the sound grain) passes under the lower edge of a partition situated in the water
and is carried, by the current produced in the water by the rotation of a drum, to
the periphery of the said drum by which it is caught up and lifted out of the water.
The impurities such as stones, earth, or sand, sink, on account of their greater
specific gravity, to the bottom of the vessel whilst the too light grain-that is to
say, the unsound grain-does not descend as far as the lower edge of the partition,
and therefore does not get caught by the current in the water surrounding the
drum, but floats upwards to the surface, whence it can be removed through an exit
passage.
The accompanying drawings illustrate a machine according to my invention,
Fig. 1 being a vertical longitudinal section,
Fig. 2 a vertical cross section; and
Fig. 3 a plan thereof.
In the casing of the machine there is suitably mounted a drum B. In front
of this drum-that is to say, between the grain as it falls into the machine and the
drum-there is arranged a partition C which extends down to a certain depth and
can be adjusted vertically and laterally to any desired position by any suitable
means... Between the front wall of the casing and the partition C there is arranged
at a certain height above the water, a grain inlet or hopper E from which the grain
is allowed to drop into the water. Between the back wall of the casing and the
drum, and so as to be just above the level of the water contained in the casing,
there is arranged a worm I which is situated in a casing 1. On the latter there is
arranged a stripper K which bears against the drum and serves to remove the grain
therefrom and to guide it to the worm. In the front wall of the casing there is
arranged a discharge-passage F for the light or unsound grain. A slide f serves
to regulate the outflow through the passage F and must be adjusted to suit the
level of the water. G is a water-inlet, and H a passage (provided with a valve
or like closing device) for the discharge of stones and mud. Above the outlet H
and below the drum is situated an agitator D which has for object to separate or
loosen from one another grains that may be caused to sink whilst adhering to
earthy matter, and then to cause the grains to rise and pass into the current
produced by the drum. The drum B and also the casing 1 are suitably perforated ;.
the former may consist of a framework covered with perforated material such for
instance as sheet-metal. The drum revolves from C towards I in the direction of
the arrow and produces in the water that stands at a suitable level in the vessel,
and chiefly between the partition C and the opposite periphery of the drum, a
current which carries away with it the grain that passes below the lower edge of
the partition C, so that the said grain is then lifted by the drum above the level
of the water and be conveyed towards the conveyor casing I.
The mode of operation of the machine is as follows:-
The grain that is to he freed from contained stones or earthy matter, drops from
the hopper E down through the space A° (Fig. 1) into the water contained by the

page_text: casing A, and becomes immersed therein. The sound grain of full weight sinks
until it reaches the bottom edge of the partition C, where it passes into the current
produced by the drum B, and, enters the space between the partition and the
surface of the drum B where it rises by upward displacement to the surface of the
water beyond which it is then carried by the drum. The washed grain on
reaching the stripper K is guided thereby into the conveyor casing I', where it is
engaged by the screw-conveyor I, whilst the water in excess flows off through the
perforated conveyor casing. The light or unsound grain will become immersed
only to a slight depth, and thus it will not reach the lower edge of the partition C,
so that it cannot be caught by the aforesaid current. Upward displacement due to
its buoyancy brings this grain to the surface again, whence it passes into the
passage F and escapes. The heavy substances contained in the grain such as stone
and earthy impurities-are not carried away by the current, but sink to the bottom
and escape past the agitator D into the stone-discharge H, whence they can be
removed continuously or at intervals. Auy grain that may sink with the stones or
dirt to the bottom will be agitated by the rapidly revolving agitator D, so that
whilst the earthy matter will sink down further without hindrance, the grain will
be driven upwards by the agitator, so that it will be caught by the current produced
by the drum, pass in between the surfaces of and B, and take the course of the
sound grain herein before described.
So much water is supplied through the water-inlet G as is necessary to take the
place of that carried off by the grain and also of that necessary for floating away
the light or unsound grain.
By placing the partition C higher or lower, or shifting it laterally, the period
during which the grain is in contact with the water can be prolonged or shortened-
that is to say, the grain may be caused to pass sooner or later into the current
produced by the drum, and thus become wetted to a greater or less extent.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed I declare that what I
claim is :-
1. A machine for washing grain and the like with simultaneous separation of the
light or unsound grain and also of the heavier constituents such as stones and
earth, comprising a casing to contain the washing water and having mounted in it a
revolving drum, and a partition which is arranged in front of the said drum, and
has its lower edge arranged to be immersed to a suitable depth in the water, the
arrangement being such that when grain is allowed to drop into the water in front
of the said partition light or unsound grain will not pass below the lower edge of
the partition, whereas the sound or sufficiently heavy grain will do so and pass
into the space between the partition and the drum and be finally lifted out of the
water by the said drum, substantially as hereinbefore described.
2. A machine of the kind specified in the preceding claim, constructed with a
discharge passage for light or unsound grain and with an agitating device arranged
below the revolving drum so as to produce a current of water such that any sound
grain that may have sunk to too great a depth will be caused to pass upwards into
the space between the partition and the revolving druin, substantially as herein before
described.
3. My improved machine for washing grain and the like, constructed, arranged,
and operating substantially as herein before described with reference to and shown
in the accompanying drawings.
Dated th: 54h 12000