Improvements in Pneumatic Apparatus for Conveying and Depositing Grain and other Granular or Pulverulent Matters.
Year: 1894

page_text: Date of Application, 3rd Jan., 1894
Complete Specification Left, 3rd Oct., 1894-Accepted, 22nd Dec., 1894
Improvements in Pneumatic Apparatus for Conveying and Depositing
Grain and other Granular or Pulverulent Matters.
I FREDERIC ELIOT DUCKHAM of Millwall Docks, London, E. Civil Engineer,
do hereby declare the nature of this invention to be as follows:-
My invention relates to pneumatic apparatus for conveying and depositing grain
and other granular or pulverulent matters by a current of air under pressure and
consists in an improvement in the discharge nozzle of the conveying pipe by which
the grain or other matters conveyed by the air current are deposited.
The improvement has for its object to enable the grain or other matter to be
deposited by the air current in small or confined spaces left vacant after the greater
part of a vessel's hold, or a storage bin in a granary, is filled, such for example as
the corners immediately beneath the deck of the vessel, or the ceiling of the bin,
into which the grain, &c., fed in from above cannot flow by gravity by reason of
the fact that the surface of the mass of grain already filled into the hold or bin lies
at the natural angle of repose and meets the deck or ceiling above. Such spaces
have heretofore only been able to be filled by the operation of trimming by hand
labor, which it is the object of my invention to avoid.
In all previous attempts to deposit grain directly in such confined spaces, it has
been found that the velocity of the air current necessary for the conveyance of the
grain through the conveying pipe is so great on emerging from the discharge
nozzle introduced into a confined space, such as above referred to, that the scour of
the air current in escaping from the said space, and the rebound of the grain on
striking the walls of said space, causes the grain to be carried away instead of
being deposited in the vacant space, so that for however long a time the jet of
and hence
grain may be directed into the said space, it could not be filled up,
recourse has always been had to hand labor for trimming.
My invention consists in causing the velocity of the air jet to be so diminished
before it emerges from the nozzle that whilst the rate at which the grain, &c., is
conveyed through the conveying pipe is not affected, the air on emerging from the
nozzle escapes quietly without carrying the grain away with it, the grain being
deposited in the confined space until the latter is quite filled up. This I accomplish
by providing the conveying pipe with a discharge nozzle of greater diameter than
said pipe so that the compressed air on entering the nozzle will expand and be
correspondingly diminished in velocity, whilst the grain carried by it will retain
by virtue of its inertia a certain amount of acquired momentum so that its velocity
although reduced will not be reduced to so great an extent as that of the air, the
result being that the particles of grain will become somewhat massed together and
be less liable to be carried off by the escaping air.
Reference is to be had to the accompanying drawings, forming part of this
Specification, wherein
Figures 1 and 2 show longitudinal sections of two slightly modified forms of my
improved nozzle applied to a conveying pipe, and
Figure 3 is a cross section of a vessel being loaded, showing the spaces into which
the grain, etc., cannot flow and into which it is conveyed and there deposited by
means of my improved nozzle.
A is the ordinary flexible conveying pipe through which the grain, etc., is

page_text: conveyed by a current of air under pressure. B is a nozzle or length of tube
connected to the end of pipe A, said nozzle tube exceeding the pipe A in diameter
in about the proportion of 3 to 1 whilst the length of this nozzle B is about equal
to ten times its own diameter. I have indicated these proportions as those found
to answer best in actual practice but I do not limit myself absolutely thereto.
The nozzle B may either be straight as shown in Figure 1, or be slightly curved
as shown in Figure 2, so as to be more favorably directed into the space to be filled.
In either case the grain projected through it from the pipe A tends to fall towards
the lower side of the nozzle and flow out therefrom in a compact stream at a
reduced velocity whilst the air separated from it escapes quietly without disturbing
the mass of grain already deposited.
CC are the vacant spaces beneath the deck of the ship at either side of the
hatchway, for instance, into which the grain, etc., will not flow when the hold is
nearly filled up, owing to the heaped-up surface of the mass sloping at the natural
angle of repose meeting the coamings of the hatchway, which intercept the further
flow of the grain down the sloping surface, so that however much the mass may be
heaped up in the hatchway, these spaces C will not be filled so long as the ship
remains on an even keel.
Dated this 3rd day of Januar 1904
F. E. DUCKHAM,
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.
COMPLETE SPECIFICATION.
Improvements in Pneumatic Apparatus for Conveying and Depositing
Grain and other Granular or Pulverulent Matters.
I, FREDERIC ELIOT DUCKHAM, of Millwall Docks, London, Civil 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 pneumatic apparatus for conveying and depositing grain
and other granular or pulverulent matters by a current of air under pressure, and
consists in an improvement in the terminal nozzle of the conveying pipe by which
the grain or other matters conveyed by the air current are deposited.
The improvement has for its object to enable the grain or other matter to be
deposited by the air current in small or confined spaces left vacant after the greater
part of a vessel's hold, or a storage bin in a granary, is filled, such for example
as the corners immediately beneath the deck of the vessel, or the ceiling of the bin,
into which the grain, etc., fed in from above cannot flow by reason of the fact that
the surface of the mass of grain already filled into the hold, or bin, lies at the
natural angle of repose and meets the deck or ceiling above. Such spaces have
heretofore only been able to be filled by the operation of trimming by hand labour,
which it is the object of my invention to avoid.
In all previous attempts to deposit grain directly in such confined spaces it has
been found that the velocity of the air current is necessarily so great that the grain
is carried away instead of being deposited in the vacant space, so that for however
long a time the jet of grain may be directed into the said space it could not be
filled up and hence recourse has always been had to hand labour for trimming.
By my invention, the rate at which the air and grain flow through the conveying
pipe is not diminished, but the air is caused to escape quietly without carrying the
grain away with it, the grain being deposited in the confined space until the latter

page_text: is quite filled up. This I accomplish by providing the conveying pipe with a
discharge nozzle of greater diameter than said pipe, so that the compressed air on
entering the nozzle will expand and be correspondingly diminished in velocity,
whilst the grain carried by it will be somewhat massed together in the nozzle and
flow out in a slowly, but continuously, moving compact stream.
Reference is to be had to the accompanying drawings, forming part of this
Specification, wherein
Figures 1 and 2 shew longitudinal sections of two slightly modified forms of my
improved nozzle applied to a conveying pipe, and
Figure 3 is a cross-section of a vessel being loaded, shewing the spaces into
which the grain, etc., cannot flow, and into which it is conveyed and there deposited
by means of my improved nozzle.
P is the ordinary flexible conveying pipe through which the grain, etc., is
conveyed by a current of air under pressure. N is a nozzle or length of tube
connected to the end of pipe P, said nozzle tube exceeding the pipe P in diameter
in the proportion of about 2 or 3 to 1, whilst the length of this nozzle N is about
equal, say, from five to ten times its own diameter. I have indicated these proportions
as those found to answer best in actual practice, but I do not limit myself absolutely
thereto.
The nozzle N may either be straight, as shewn in Figure 1, but it is preferably
curved, as shewn in Figure 2, so as to be more favourably directed into the space
to be filled. In either case the grain projected through it from the pipe P tends
to fall towards the lower side of the nozzle and flow out therefrom in a compact
stream at a reduced velocity, whilst the air separated from it escapes quietly
without disturbing the mass of grain already deposited.
V V are the vacant spaces beneath the deck of the ship, at either side of the
hatchway for instance, into which the grain, etc., when delivered into the hatchway
will not flow when the hold is nearly filled up, owing to the heaped-up surface of
the mass sloping at the natural angle of repose meeting the coamings of the
hatchway which intercept the further flow of grain down the sloping surface so
that, however much of the mass may be heaped up in the hatchway, these spaces V
will not be filled so long as the ship remains on an even keel.
Having now particularly described and ascertained the nature of the said inven-
tion, and in what manner the same is to be performed, I declare that what I
claim is :-
1. In pneumatic apparatus for conveying and depositing grain and other granular
or pulverulent matters by a current of air under pressure, the combination, with
the conveying pipe for said granular matters and air, of a terminal expansion
nozzle of uniform diameter from end to end and of larger sectional area than said
pipe, whereby the granular matters can be forced to a given point in a compact
stream and the air required to force it thereto be dissipated before it reaches
said point.
2. In pneumatic apparatus for conveying and depositing grain and other granular
or pulverulent matters by a current of air under pressure, the combination, with
the conveying pipe for said granular matters and air, of a terminal expansion
nozzle of larger sectional area than said pipe, said nozzle being curved and of
uniform diameter from end to end, whereby the granular matters can be forced to
a given point in a compact stream and the air required to force it thereto be
dissipated before it reaches said point.
3. In pneumatic apparatus for conveying and depositing grain and other granular
or pulverulent matters by a current of air under pressure, the combination, with
the conveying pipe for said granular matters and air, of a terminal expansion
chamber or discharge nozzle of a suddenly enlarged sectional area greater than
said pipe, said enlargement beginning near the junction with the pipe and continuing
through the outlet, whereby the granular matters become massed at a given point

page_text: and form a compact stream outflowing at a diminished velocity, whilst the air
required to force it to that point passes off free of the grain, substantially as and
for the purpose specified.
Dated this 3rd day of October 1894.
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.